Essential oils to support olfactory rehabilitation after loss of the sense of smell post infection.


Heather Dawn Godfrey. P.G.C.E., B.Sc. (Joint Hon)

Author of Healing with Essential Oils, Essential Oils for the Whole Body and Essential Oils for Mindfulness and Meditation – published by Inner Traditions, Bear & Co., Vermont USA




This article explores the role of essential oils in aiding recovery of loss of the sense of smell instigated by colds and ‘flu and/or respiratory infection, and focuses on the following themes:


  • Essential oils to support olfactory rehabilitation
  • Essential oils and viruses: reviewing the science
  • How the body’s immune system works: a brief overview
  • How essential oils work with the body
  • Recovering the sense of smell: an anecdotal account
  • What is a virus – deeper dive?


Essential oils to support olfactory rehabilitation after loss of the sense of smell post infection.


In truth, anosmia (loss of the sense of smell) is not completely understood. The sense of smell is a complex process involving various nerve and brain system mechanisms, particularly within the limbic system, where odour and scents are registered and instinctively detected.  Response to odour is reflexive, psycho-emotional, neurological and hormonal.


Symptoms of colds and ‘flu range from mild to severe, depending on the age, health condition and immune response of the individual.  In some instances, symptoms, especially cognitive dysfunction (brain fog) and extreme fatigue, may linger for some time after recovery. (Venkatisan 2021)   


Essential oils may be usefully applied preventatively and may also quell symptoms (head aches, muscle aches and pains, brain fog, fatigue, congestion, inflammation, and so on).  Before continuing, a note of caution regarding the use of essential oils if the lungs are infected and breathing capacity is compromised – direct olfactory inhalation of essential oils is not advisable due risk of causing further irritation of the lungs (irritation of the alveoli may impede gaseous exchange and detrimentally reduce the amount of oxygen absorbed and available to cells).


How colds and ‘flu cause loss of the sense of smell


Inflammation of the nasal passages causes the tissues therein to become swollen, which in turn reduces the volume of scent-infused air sweeping across odour receptors in the epithelium, which is situated at the top of the nasal cavity; consequently fewer odour molecules are available to detect.  The olfactory epithelium and its connecting peripheral nerves may be damaged as a consequence of swelling and infection; detection and stimulation of the neural messaging system is impeded, thus relay of nerve transmission to the limbic system, where scent signals are registered and recognised within the brain, is compromised.  


The surface of angiotensin converting (ACE2) receptors, among other cells, are coated in a protein (ACE).  This coating acts to prevent cell damage and death. ACE receptors are expressed in almost all tissues, but ACE2 is particularly expressed in the gut, capillary endothelial cells, cardiovascular cells, on alveoli epithelial cells, and cells within the brain.  ACE2 coated cells and receptors surround and provide structure and nutrients to the olfactory epithelium at the top of the nasal cavity.  When this coating is damaged or diminished, the epithelium and the hair-like olfactory nerves projecting through the epithelium from the olfactory bulb are compromised.


In most incidents, the immune system prevents development of serious infection progressing from the upper respiratory tract (that is, nose and throat) to the lungs.  Severe cases of lung infection may result in damage of the alveoli (ACE2 receptors are also located on the alveoli cells surface) causing severe breathing difficulties and other pneumonia-like symptoms.  Infected and/or damaged alveoli detrimentally impedes gaseous exchange (simply, oxygen intake and carbon dioxide excretion), which, in turn, impedes efficient oxygenation of cells throughout the body.  When this happens, carbon dioxide begins to build up in the body; carbon dioxide build-up damages cells and tissues within organs (lungs, liver, kidney, heart, pancreas, intestines and brain) and may result in fluid build up; fluid build up in the lungs causes pneumonia-like symptoms. In rare cases, lung infection is not immediately obvious or detectable; breathing does not appear to be inhibited, yet oxygen levels within cells plummet (this condition is likened to altitude sickness). (Ni et al 2020)


Sometimes, the sense of smell diminishes without any obvious signs of damage or disruption.


Up to fifty per cent of people report loss of their sense of smell during or just after colds, ‘flu and/or respiratory infection.  Most people recover their sense of smell once, or soon after, the symptoms of infection subside.  In some instances, however, the sense of smell only partially returns or is never regained.  Some pathogens are able to enter the higher brain region via the epithelium and olfactory nerve portals, which may add further complication.  (Rebholz et al 2020)


Applying essential oils as aids to recover of the sense of smell


Professor Thomas Hummel and colleagues (Damm et al 2013, Hummel 2009) devised a system of re-training olfactory receptors after loss of the sense of smell, originally using four distinctive odour molecules extracted from essential oils – phenyl ethyl alcohol (found in rose), eucalyptol (found in eucalyptus), eugenol (found in clove) and citronellal (found in lemongrass) – to stimulate growth of olfactory receptors and epithelium supporting cells at the roof of the nose.


In a BBC interview (29th November 2018) Professor Hummel (ear, nose and throat expert at the University of Dresden, Germany) confirmed that after deliberately sniffing each scent for twenty seconds in the morning and evening, using ‘Sniffin Sticks’ (pen-like tubes containing the scents, which are held just at the entrance of each nostril) as a delivery mechanism, forty-five per cent of those tested recovered their sense of smell, whereas only twenty-two per cent of people recovered without smell training. Some people experienced change in their perception of odours; this was attributed to the fact that not all receptors were recovered, a phenomenon which sometimes also resulted in alteration in the detectable nuances of some smells.


Hummel et al’s experiment was repeated by Professor Claire Hopkins, President of the British Rhinological Society and Consultant Ears Nose and Throat Specialist, who described the process in an interview for Sky News (8th January 2021) as ‘physiotherapy for the nose’, a form of exercise that stimulates nerve recovery and re-establishes connection within the brain.


Applying the same four scents (this time, in their complete essential oil form), Professor Hopkins described how these were ‘dropped’ onto a small pad in a jar; removing the lid, each of the four jars is held to the nose in turn and sniffed for twenty seconds two or three times a day. Professor Hopkins confirmed this process enhanced the rate of long-term recovery considerably. She too observed some changes in the sense of smell post recovery in ways that appeared to improve odour perception.


Researchers generally acknowledge that response to scent(s) wanes after a few weeks, even a few minutes if the scent is continuously experienced.  The brain becomes saturated once familiar with a scent; even though still present, the odour appears to disappear, is absorbed into background awareness.  For this reason, it makes sense to change the scents applied every few weeks to avoid over familiarisation (or recognition saturation).  Other essential oils or scents applied in similar experiments include: cinnamon, orange, peppermint, thyme, rosemary, jasmine, vanilla, even chocolate.


In some instances, whole essential oils are used, in others, as above, distinctive isolated fractions are used in smell tests (for example, menthol, eugenol, 1,8-cineole, phenyl ethyl alcohol, citronellal – see also ‘reviewing the science’ below).  In their whole form, essential oils are more likely to exhibit capacity to influence more than one element of the body at the same time, and sometimes demonstrate a synergistic effect (either with each other if more than one essential oil is applied and / or with other chemicals).  For example, not only do essential oil molecules stimulate the sense of smell (and an immediate emotional response instigated via olfactory connection with the limbic system), but essential oils also stimulate anti-inflammatory, anti-microbial, anti-viral, and tissue healing and regenerating responses. Indeed, the essential oils applied in the above smell recovery programmes (rose, eucalyptus globulus, clove bud and lemongrass) demonstrate, among other qualities, strong anti-viral and antimicrobial properties, especially clove, lemongrass and eucalyptus (see also fig 1), and tissue regeneration, especially rose. Therefore, as part of the process of smell recovery, it is likely that these oils in their whole form equally support the immune system re-establish viral and microbial balance, while also aiding tissue regeneration and nerve recovery. (Godfrey 2022)


Essential oils and viruses: reviewing the science


Colds and influenza, including COVID-19, are classified as corona viruses.  Corona viruses generally instigate symptoms that are typically cold-like or ‘flu-like; for example, fever, chills, body aches, coughs and mucous excretion, and in some cases loss of sense of smell.  COVID-19 produces flu-like symptoms (for example, fever, inflammation, a dry cough, and shortness of breath) that may continue to linger for some time beyond initial infection.  Symptoms typical of a common cold include: a sore throat, nasal swelling and mucous congestion and expression.


Essential oils to ease symptoms of colds and ‘flu and other corona viruses


Asif et al (2020) reviewed research (in silico computer-aided docking and in vitro studies) which explored COVID-19 and therapy that applied essential oils with antiviral, anti-inflammatory and immunomodulatory properties.  They proposed in conclusion that essential oils do have activity against SARC-CoV-2, but recommend further in vitro (lab) and in vivo (life) studies to establish the safe dose and clinical efficacy of essential oils.  The essential oil components that appeared to demonstrate anti-viral actions were:

  • menthol (found in mint oils and geranium)
  • eugenol (found in cloves)
  • carvacrol (found in oregano, wild marjoram and thyme)
  • cinnamaldehyde (found in cinnamon bark and cassia bark)
  • geraniol (found in wild bergamot, palmarosa, lemon thyme, and geranium)
  • 1,8-cineole (found in eucalyptus, cajeput, and Spanish marjoram)
  • L-4-terpineol (found in tea tree).


In another review of research literature, which explored the potential for essential oils to treat SARS-CoV-2 infections, de Silva et al (2020) found that, out of 171 essential oil components scrutinised in these studies, (E,E)-alpha-farnesene, (E)-beta-farnesene, and (E,E)-farnesol (found in German and Moroccan chamomile and rose) appeared to demonstrate the best, although weak, anti-viral potential against SARS-CoV infections. They acknowledged that essential oil components may act synergistically and that essential oils may also potentiate other anti-viral agents. They concluded that essential oils may provide some relief from symptoms of COVID-19, therefore, also other similar cold and ‘flu corona viruses .


Indeed, the antibacterial, anti-fungal and anti-viral properties of essential oils are well evidenced (see fig 1).  Essential oils are adaptogens (that is, they aid the body manage stress and maintain balance or homeostasis), a phenomenon supported by the complex array and combination of molecules present within their chemical mixture, which enhances their ability to appropriately target their actions according to need or requirement; also a phenomenon that lends itself well to immune system support in general.


Fig. 1. Essential Oils that have demonstrated anti-infective, anti-viral and anti-microbial properties (for references see the end of this article, and for detailed information about the overall properties of each of the essential oils listed below see Godfrey 2022, Healing with Essential Oils)



Australian Sandalwood, Basil (linalool), Bergamot (wild), Cajeput, Cassia bark, Chamomile (German), Cinnamon Bark, Citronella, Clove, Cypress, Eucalyptus, Geranium, Hyssop, Lemon, Lemongrass, Juniper, Marjoram (wild, Spanish), Melissa (Lemon Balm), Oregano, Palmarosa, Patchouli, Peppermint, Ravensara, Tea Tree, Thyme (lemon).

Specific components identified(E,E)-farnesol, (E,E)-alpha-farnesene, (E,E)-beta-farnesene, eugenol, carvacrol, cinnamaldehyde, geraniol, 1,8-cineole, L-4-terpineol



Bergamot, Carrot Seed, Cinnamon (bark, leaf), Citrus Oils, Clove Bud, Eugenol, Fennel, Geranium, Lavender, Lemon, Lime, Orange Bitter, Oregano, Palmarosa, Eucalyptus Globulus, Patchouli, Peppermint, Pine, Rose, Rosemary, Sandalwood (Australian), Tea Tree, Thyme Red, Vetiver, Winter Savory.


Anti-microbial (general)

Carrot Seed, Cinnamon (bark and leaf), Clove, Eucalyptus Globulus, Geranium, Lavender, Patchouli, Pine, Rose, Rosemary, Tea Tree Vetiver.

Specific components identified – eugenol, geranial


Cell-death (membrane penetration, reproduction inhibition)

Cajeput (1,8-cineol), Cassia bark, Cinnamon bark (cinnamaldehyde), Eucalyptus (1,8-cineole), Lemongrass, Marjoram (Spanish), Rosemary, Tea Tree.


Broad spectrum (affective against a wide variety of organisms)

Cinnamon (bark, leaf), Eucalyptus, Lavender, Rose.



Clove + Rosemary

Sandalwood (Australian) + Myrrh

Sandalwood (Australian) + Vetiver,

Frankincense + Myrrh

General: Lemongrass, Geranium



Bergamot, Cinnamon (cinnamaldehyde), Garlic, Lemongrass, Nutmeg, Oregano, Rose

To find out more about the individual properties of these essential oils, see Healing with Essential Oils (2022) 


An essential oil can comprise of a complex mixture of at least a hundred, and in some instances several hundred, organic chemical components in variable quantity and combination, depending on the type of plant and the quality and chemical content of the essential oil it yields.


Indeed, the chemical composition of an essential oil is influenced by various factors; such as, plant species, geographical location and environmental conditions of growth, the age of a plant,  and also the method of extraction employed. and so on. These factors (including how fresh an essential oil is at the time of use, its conditions of storage, its rate of oxidisation, and so on) influence the chemical composition and potency of essential oils. For example, lavender angustifolia harvested and distilled in northern France and tested within a week will differ in composition from the same oil tested six months or twelve months later, and from lavender angustifolia harvested and distilled in Spain, or the UK, and so on. So many variables to pin down that are not always acknowledged in study results. (Godfrey 2022)


Additionally, in terms of applying essential oils as a treatment for ‘flu and  COVID-type infections, the timing of intervention from the onset of infection is apparently significant. For example, Shi et al (2020) recommend that, in the case of COVD-19, the immune system should be boosted during the initial stage of infection, when there is better chance infection will be more easily contained and controlled, but should be suppressed during the inflammatory phase when infection has reached the alveoli in the lungs; at this stage, oxygen uptake is critical and can be negatively compromised by over reaction of the immune system and/or, as established previously, through irritation caused by essential oils or other chemicals (as established above).


Essential oils exhibit preventative potential (Kumar 2020).  However, their effectiveness also depends on general background health (co-morbidities and an already compromised immune system significantly influence predisposition to infection and may prolong the rate of recovery).  Indeed, the preventative qualities of essential oils are enhanced when combined with other supportive strategies (and vice versa), such as, exercise, sunlight exposure (vitamin D) and fresh air, an unprocessed, fresh and organic diet, and sufficient vitamin and mineral intake, and so on.


Vitamin C, for example, was applied in Wuhan and New York hospitals during the initial outbreak of COVID-19 in 2020, and demonstrated some supportive success (Zuo 2020, Hemila 2003); high doses of vitamin C modify susceptibility to various bacterial and viral infections.  Vitamin D3 regenerates endothelial lining in blood vessels and is shown to minimise alveolar damage (Kakodkar et al 2020).  Vitamin B3 is highly lung protective and may be useful at the onset of coughing (Shi et al 2020). Zinc reduces inflammation and boosts the immune system. Vitamin A helps the lungs, heart, and kidneys, and other organs, function properly (Ayyadurai 2020).


Low dose of Hydroxychloroquine is also reported to quickly alleviate symptoms (and also to act as a preventative), especially when taken during the early phase of infection (Cahill 2020).


These strategies support the immune system and aid the body recover from infection or disequilibrium.


Then, there are the psycho-emotional and subjective phenomenological influences that essential oils procure.  For example, the influence essential oils have on the limbic system (memory, mood and emotion) and the pituitary gland (hormone and endocrine system) (Godfrey 2022, 2020, 2019), and the trigeminal nerves in terms of physical sensations felt in response to essential oils (Leffingwell 2021). The boundaries between physical, psychological and emotional (body, mind, and spirit) often overlap. Indeed, feeling happy, relaxed and calm, positive and optimistic demonstrably influences physical function; heart rate, blood pressure, cortisol levels, endorphin release, digestion, and so on.  Attitude, taking control, responsibility, for one’s health and wellbeing (which is a form of positive optimism) also influences outcomes (Godfrey 2022, Gao et al 2017, Conversano 2010).  This is where essential oils may come into their own; with the added bonus that they also possess anti-viral, antimicrobial, and tissue healing properties.


How the body’s immune system works: a brief overview


The immune system works in collaborative symbiotic harmony with the body’s micro-biome and virome.


Briefly and simply, the immune system is a complex network of cells and proteins (cytotoxic T Lymphocytes, natural killer cells, anti-viral macrophages) that defend the body against pathogenic infection (or bacterial or viral proliferation) and systemic harm or imbalance.


The innate immune system provides initial ‘front line’ protection; however, while fast acting, it is non-specific in its action.


The adaptive immune system, on the other hand, instigates more specific honed responses, that are not always immediate.  Helper T Cells, for example, recognise pathogenic infected cells (foreign or toxic particles, or bacteria, or rogue cells such as cancer cells) and produce cytokines (a hormone-like protein) that attach to the infected cell, then triggers or stimulates specific responses by target cells, or anti-bodies.  Antibodies (a unique Y-shaped protein made and mutated within the body) are produced and employed by the adaptive immune system to recognise and neutralise pathogenic bacteria, other microbes or particles (antigen); once produced, these antibodies remain in the body for some time. The adaptive immune system records each pathogen ever defeated, so recognises it quickly again and destroys it. (Schrader 2015)


Primary immune system organs (lymphoid organs):

  • Bone marrow (B cells)
  • Thymus (T cells)

The thymus receives uncommitted lymphocytes from bone marrow and is actively engaged in T-lymphocyte proliferation.  The thymus is very large in babies but shrinks after puberty.


Secondary Immune System Organs

  • Spleen
  • Lymph nodes
  • Tonsils and adenoids
  • Appendix
  • Mucosal associated lymphoid tissues (lungs, throat, nose and gut/bowel)


Immune System Cells


  • B-lymphocytes are developed in bone marrow and produce a type of protein known as anti-bodies. They control infections by producing neutralising antibodies and antibody-dependent cellular cytotoxicity (cell-death), ‘fight’ pathogens and send signals that control the immune systems response to threats. They support the adaptive (acquired) immune system and produce a slow but long-lasting protective response.  For example, antibodies recognise and stick to foreign molecules that invade the body, thus, ‘branding’ or identifying the invading molecules – more and more antibodies are then produced until the invader is defeated.  Antibodies (or sentinels) set up a future recognition mechanism.


  • Plasma cells, found in the watery part of blood, are white blood cells that originate in the lymphoid organs as B cells; differentiated B-lymphocytes that are capable of secreting immunoglobulin or antibodies (in response to contact with antigens – toxins, chemicals, bacteria, viruses or other substances that come from outside the body), they also play a significant role in the adaptive immune response. Some body tissues, including cancer cells, have antigens on them that can cause an immune response.


  • T-lymphocytes, also develop in bone marrow, instigate a fast-acting immediate defensive response. They ‘fight’ infection.  Part of the innate (natural) immune system, T-lymphocytes distinguish ‘self’ from ‘other’ and manage, control and curtail exaggerated immune responses. The skin barrier forms part of the innate immune system.  Sneezing, inflammation and itching are examples of innate immune system reactions. (T-lymphocytes are supported by intake of a fresh healthy diet, vitamin C, vitamin D and sunshine).


  • Large lymphocytes are natural killer (NK) cells that limit the spread and subsequent tissue damage caused by cancers and microbial infections (these cells secrete deadly chemicals which make the infected cells content leak out).  Natural killer cells can develop and mature in the bone marrow and secondary lymphoid tissues (including tonsils, spleen, and lymph nodes).


  • Phagocytes surround (ingest) and kill or eliminate micro-organisms, foreign substances or particles, and apoptotic (self-destructed) cells. They are scavengers which constantly move around to remove dead cells and foreign bodies such as pathogenic microbes.  They are found in blood (neutrophils and monocytes), bone marrow (macrophages, monocytes, sinusoidal cells and lining cells), bone tissues (osteoclasts), gut and intestinal Peyer’s patches (macrophages), tissue dendritic cells (found in bone marrow and the thymus), and mast cells (found in connective tissue cells throughout the body).


The role of blood cells


  • White blood cells (leukocytes) found in the liquid (plasma) part of blood are normally inactive, but when ‘switched on’ by contact with invading bacteria will destroy bacterial cells to curtail infection and disease.


  • Red blood cells (erythrocytes) transport oxygen around the body.


Further protective dynamics of immunity


  • Tough and flexible with a surface of dead skin cells packed with keratin (a fibrous structural protein), the skin provides a protective barrier and stops invasion of microbes.


  • The lining of the mouth, throat and lungs, and reproductive system, is constructed from layers of cells that secrete large amounts of watery fluid known as mucous. Mucous traps invading microbes.  For example, the anti-bacterial enzyme, lysozyme, present in mucous, helps keep micro-organisms under control and aids the lung to expel foreign particles.


  • Stomach acidity caused by hydrochloric acid secreted by the stomach lining destroys harmful pathogens.


How the body repairs itself: 


  • When bones break, new cells are formed in a blood clot (coagulated blood cells) at the broken bone ends – these cells transform into cells that knit the bones together again.


  • Replaces worn out or dead cells. In skin tissue, for example, the dead outer layer is replaced by new cells, formed in the living lower layer where rapidly dividing cells produce a constant supply of replacement-cells.


  • Repairs the wall of damaged blood vessels. For example, a quick-setting temporary patch made of platelets is formed; then, a longer-term repair is made with fibrin, which is an insoluble blood protein; finally, a permanent repair in the vessel wall is made via new cell growth.


  • Dislocated or sprained joints are immobilised by fluid in tissues (oedema) and held in place while the injured site repairs.


  • Severed nerves join up to restore feeling and sensation.


  • Brain neurons re-wire to minimise damage.



How essential oils work with the body


As previously established, essential oils are multi dynamic adaptogens; that is, they support the immune system and the body’s resilience to stress. They stimulate the limbic system (the emotional brain), are antimicrobial, skin healing, hedonistic, and more. They are capable of independently and simultaneously influencing various body systems.  Simply, for example, an essential oil selected to add to a dry skin remedy, may also ease mild depression and/or uplift mood and emotion, while at the same time sharing its anti-microbial qualities to avert infection. This adaptive quality is also attributed to the affinity of certain essential oil molecules (one example being beta-caryophyllene) with the body’s endocannabinoid system, which plays a role in a range of functions and processes, such as sleep, mood, memory, learning, motor control, skin and nervous function, liver function, and muscle formation.


All essential oils possess anti-pathogenic, anti-viral and anti-microbial properties to varying degrees (one of the significant roles essential oils play within plants, for instance, is to stave pathogenic proliferation). Their actions tend to be targeted in a way that does not appear to harm the terrain.  Many essential oils, for example, inhibit and/or slow the pathogenic growth of bacteria, yeasts and moulds; certain essential oil molecules (especially, for example, those found in eucalyptus, lemongrass, rosemary and tea tree} affect the lipid structure of bacterial cell membranes in a way that increases its permeability, causing the bacterial cell to lose ions and other cellular components, which leads to the cells death.   Some essential oils act synergistically and potentiate other anti-viral/anti-bacterial or medicinal agents, including biomedical antibiotics. (de Silver et al 2020, Nazarro et al 2013).


Some essential oils possess broad-spectrum bactericidal and anti-viral qualities, while others are more specific in their action, depending on the chemical composition of the essential oil and the type of microbe or viral particle; broad-spectrum in this context does not mean a single essential oil or blend of essential oils will kill or disrupt pathogenic proliferation of all viruses or all bacteria. Some essential oils stimulate the immune system and the body’s self-regulatory process. (See, for example, fig 1.) (Vasey 2018)


Essential oils may act preventatively and appear especially useful during the early stages of infection. They support the immune system by promoting activity of lymphocytes (immune supporting white blood cells), increasing phagocytosis (the process by which an immune cell uses its plasma membrane to engulf large particles, such as viruses or an infected cell), and induce interferon production (interferons are signalling proteins that ‘interfere’ with viruses to prevent them from multiplying). (Sandner 2020, Han 2017, Kuriyama 2005)  They also ease symptoms, such as those associated with colds and ‘flu; for example, headaches, nasal and sinus congestion, cough, muscle aches, and other symptoms such as insomnia, depression and anxiety.


Significantly, unlike conventional antibiotics, essential oils do not appear to negatively disrupt balance of the body’s micro biome. However, this is not to say they are not capable of doing so or that the immune system will not develop resistance (or over react) to essential oils or their components. It is true that the molecular complexity of essential oils may delay resistance to them, but this delay is negated if essential oils are repeatedly overused or inappropriately applied.  It is also important to remember that when extracted from their original plant source, essential oils are rendered highly concentrated, therefore, one drop of essential oil is very potent.  A way to avoid resistance or chemical saturation, is to abstain from using essential oils intermittently and, if used regularly, to also change or vary the essential oil or blend of essential oils.


For further information about the safe and appropriate application of essential oils, see Godfrey Healing with Essential Oils (2022), and Essential Oils for the Whole Body (2020), also Tisserand and Young Essential Oil Safety (2014)


Essential oils and the sense of smell


When we smell and acknowledge the scent of a flower or a fruit, even the scent of the soft skin of a newly born infant, we are responding to messages instigated by odour molecules permeating our immediate environment (Godfrey 2022). Neurobiologist, Leslie Vosshall, of Rockefeller University (New York), estimates that the human nose, which has four hundred different types of scent receptors, can distinguish an average of at least one trillion different odours (in a range from 80 million to a thousand trillion)! (Williams 2014).


Scent molecules (terpenes and terpenoids) are detected (like a key in a lock) by olfactory receptors located at the top of each nasal cavity that in turn relay nerve impulses to the Limbic System located in the brain. Odour receptors, along with endocannabinoid receptors, are also located in other parts of the body, for example, in the skin and other organs. However, by grand design, it seems, proximity of the master olfactory portal ensures immediate awareness and an instinctive reflexive response. Initially, protectively, we instantly decipher whether something is safe or noxious (do we accept or reject it?). The sense of smell, however, is a complicated process, involving a number of neurological and psycho-emotional mechanisms.  (Godfrey 2022)


The Limbic System incorporates various functional structures located in the central paleomammalian part of the brain (including the amygdala, hippocampus and hypothalamus) that are responsible for basic physiological and emotional responses to sensory stimulation (which includes the sense of smell).  The hypothalamus functionally connects the Limbic System to the frontal lobe (where the brain rationalises and makes sense of information and sensory input) and the pituitary gland. The pituitary gland, also known as the master endocrine gland, initiates hormone release in response to sensory signals, activating either the sympathetic or parasympathetic nervous system. Depending on the nature of the stimuli, the sympathetic nervous system prepares the body for ‘fight or flight’ (protection), and the parasympathetic nervous system maintains a state of peace and relaxation (rest and digest), and disengages the sympathetic nervous system post ‘alert’, returning the body to its optimal functional resting state. (Godfrey 2022, 2019)


The trigeminal nerves also play a part in odour detection, lending sensation to the sense of smell (for example, hot, cold, tingling, even irritating).  In the previous anecdotal example, Stephanie experienced the physical coolness of menthol. Indeed, menthol found in minty essential oils produces feelings of cold at moderate concentration, but feelings of heat at high concentration. Thus, trigeminal nerve receptors add sensation to the experiential dynamics of odour perception, whether subtle or obvious, and play a role in the complex process of odour detection, identification, and consequential neuro-physio-psycho-emotional stimulation. Around seventy per cent of all odorants stimulate the trigeminal nerve receptors to varying degrees (Leffingwell 2021, Godfrey 2022, 2019)


Recovering the sense of smell: an anecdotal account


Stephanie Feuer (2019), in her article How I bought my nose back to life, eloquently shares her own journey of smell recovery, poignantly describing how she felt removed from the world in an impenetrable bubble as if swathed in cotton wool, a space where she grieved her loss of sense of smell.  She tried everything from vitamins, herbal remedies to exercise and working-out, even running up and down stairs in attempt to jog her sense of smell to life, but to no avail. Then, learning about smell training, she set up her own ‘home-made’ version, dropping essential oils on paper.  ‘I didn’t smell the eucalyptus, but I could feel it.’  (eucalyptus mostly comprises of 1-8-cineole, or eucalyptol, which elicits a cooling sensation).  Diving into her imagination, she conjured up vivid images, drawing on memory to capture the context and experience associated with those smells that delighted her, sensually immersing in the sensations,  colours, textures and emotions evoked. ‘I squeezed my eyes and tried to focus on the memory. I could almost feel the circuits firing in my brain. I breathed in. I sniffed again with desperation and abandon.’  Fragment by fragment, wisps of scent registered, but faded again.  Recognising the citrusy scent of lemon one day, she expanded her smell repertoire to work on nuances, introducing essential oils of lime, grapefruit, sweet orange and tangerine to practice distinguishing the differences.  Then there were moments of breakthrough, visiting and lingering for a moment before fading into the distance again, for example, when she noticed the scent of new wood:


We climbed the stairs, my breath quick and deep. One section of pews looked as if it had been recently replaced. As my breath slowed, I detected the scent of wood and aromatic spices, the scent lingering from the previous night’s Havdalah ceremony. It was faint but intoxicating. My husband confirmed the smell.


A year on, and Stephanie still had not fully recovered her sense of smell.  Yet, as if in compensation, she describes how she became increasingly aware and appreciative of the sensual gifts of touch and texture, music and sound, art and colours, “shaved beets, walnuts and sweet potato: a rainbow of colour and texture I now relished.”


Stephanie’s sense of smell began to recover, fragment by fragrant fragment, as she slowly began to distinguish break-through scent dynamics, especially citrusy and woody tones.  She applied essential oils to reawaken her sensual awareness and began to rediscover the multi-layered sensations instigated by the experience of scent absorption and detection; for example, the coolness of menthol, the zing of citrus fruits, and so on.  She became acutely aware of the connection between taste and smell, and the bland void left in their absence. Yet she describes how this lack was filled as her other senses were stirred.  She developed a keener awareness of tones, textures and colours, which seemed sharper and more defined, and her increased appreciation began to exceed compensation in a way that threw into relief a new found perspective of preciousness.


Fig 2.  Scent description of the four smell-test essential oils

Clove: Fresh, fruity top note, sweet, spicy, warm, woody, minty, phenolic, with warm, spicy, woody middle and dry out notes.

Eucalyptus globulus: Powerful, camphoraceous, herbal, medicinal, with a warm, woody-scented undertone, and non-descript dry out notes.

Lemongrass: Fresh, sweet, lemony, grassy, rosy, tomato leaf, with earthy undertones, with lemony, herbal, green-tea-like body notes and herbaceous, oily, dry-out notes.

Rose Otto: Complex, rich, intense, powerful, beeswax-like, highly floral, rosy, with waxy, floral, spicy (clove-like), green, metallic middle notes, then tenacious warm, floral, spicy, dry out notes. Absolute: intense, sweet, floral, rose, waxy, honey, spicy, green, cortex, geranium, metallic, with rich, spicy, sweet, floral middle notes, and warm, floral, honey-like dry out notes. Used extensively in perfumery.

NB: Distilled Rose Otto is an extremely expensive essential oil to purchase and is often substituted with less expensive solvent-extracted Rose absolute oil. Indeed, both rose otto and absolute are often adulterated, so be sure to purchase these oils from a reputable supplier.


Collectively, these essential oils stimulate the immune system, they may ease feelings of depression, grief, and anxiety and instil a sense of warmth, feeling grounded, clear-headed, and more. For example, clove bud essential oil is antiviral, stimulates memory and eases depression; eucalyptus globulus is antiviral, and is mentally and emotionally bracing and clearing; lemon is anti-microbial, averts cold and ‘flu, and eases stress related conditions; rose alleviates coughs, and eases grief, bereavement and a sense of loss, and so on.


Indeed, the qualities of these four essential oils, originally selected to stimulate the sense of smell, extend beyond simple scent detection stimulation. Each scent is distinctive, and yet complex, revealing many layers, dynamics and characteristics (see below).  Each scent also expresses qualities associated with taste. In Ayurveda and elemental modalities, for example, the taste (and qualities) of clove bud is aligned with bitter, eucalyptus leaves with pungent, lemongrass with bitter and pungent / lemon with sour and bitter, and rose petals with sweet. Bitter improves taste. Pungent (a taste between sour and bitter) is associated with the lungs and immune system, and so on (see appendix). To be clear, I am not recommending the internal ingestion of essential oils here.


Essential oils can be used singularly with great effect, but can also be blended together (using two to six complementary oils) to create a particular theme (woody, fruity, floral etc.) or desired general outcome. A simple blend, for example, I find very useful for easing the symptoms of a cold, or ‘flu, or simply to clear my head in the morning or before meditation, consists of eucalyptus globulus, geranium and peppermint (one drop of each on a tissue, or three to four of each in a nasal inhaler). This blend is refreshing, ‘clearing’, anti-viral and anti-microbial and a useful preventative remedy. Applied in a nasal inhaler, kept in a pocket or bag, this blend of essential oils can be discretely retrieved and ‘sniffed’ as and when required.


What is a virus?  A deeper dive


Relegated to background awareness while we amble through our daily life, viruses, for most of us, are considered remote, mysterious, apparently sometimes pesky, inhabitants of a distant domain – that is, until COVID-19 hit the world’s mainstream media headlines in 2020. Invisible to the eye, even smaller than bacteria, these infinitesimal particles, well, at least for most of us the notion of them, took the world by storm as they burst onto the media stage.


Viruses, though, are not ‘new kids on the block’, nor, in deed, are they really, in spite of being invisible (or rather, too small to see), backstage players. Present since the dawn of creation, apparently long before humans arrived on the scene, these infinitesimal particles tirelessly continue to play a vital and indispensable role in our evolution and our on-going ability to adapt, survive and thrive in natures ever-changing environment.


Even with the strongest electron microscope, viruses are difficult to accurately decipher.  Microbiology, in truth, has only just left the surface in its Star Ship Enterprise to dive into this universe ‘where no man has gone before’. According to the ships log, though, we know so far, that viruses are extremely diverse and novel and, together with unicellular microorganisms, such as bacteria, fungi, archaea and protists, form one of the major components of earth’s intricate environmental web. Indeed, viruses exist throughout the global eco-system, and are even found in extremely bleak locations that otherwise appear devoid of life; for example, in salty and soda lakes, the Sahara Desert, freezing polar environments, hot acid springs, in the dark cold depths of oceans, even in nuclear radiation sites.  ‘Extremophile’ is the term used to describe organisms that prefer extreme environments where other organisms could not survive. (Le Romancer 2007, Russ 2007)


In spite of being infinitesimally small, viruses apparently are believed to influence global biochemical cycles and drive microbial evolution. Many viruses are strain-specific predators (or host-hunters or parasites – that is, they are assumed to infiltrate, or hi-jack, selected cells to utilise that cells energy). In this way, they apparently kill off microbial pathogens and strains and prevent species dominance in a given environment, especially within oceans, and consequently support microbial balance. For example, as a particular microbe strain becomes dominant it’s viral predators will expand in number exponentially and kill the microbes off, leaving a niche for another microbe strain to grow into; proliferation of this microbe strain will be inhibited in turn by another viral type. But this is not their only role.


As viruses move throughout the world, they exchange vital genetic information between hosts and ecosystems, fulfilling commensal and mutualistic roles; indeed, the indispensable relationship virus’s share with and between animals, insects, plants, the environment, and other microbes and viruses, is intricate, complex, and often vital. (Rohwer et al 2009)


Viruses are apparently symbionts that operate on a continuum from mutualistic to pathogenic, depending on environmental conditions. Just as they do in the depths of the ocean, viruses play a significant role in managing and maintaining balance and harmony within our body. Indeed, most viruses are present within all of us, operating in dynamic equilibrium with our immune system; according to Professor Herbert Virgin (2013) we literally live in a ‘sea’ of viruses.  Viruses form an integral part of the body’s micro-biome.


There are apparently at least a thousand different virus species (or rather, types, as they are not alive) present in the human body, collectively numbering into the hundreds of trillions (some estimate three hundred and eighty trillion); known en masse as the human virome. By comparison, there are an estimated ‘mere’ thirty-eight trillion bacteria inhabiting the human micro biome. Viruses, bacteria and other microorganisms are found on our skin and within the microscopic aura surrounding our body, around and within orifices, within organs, including the brain, and especially within our gut, where they aid food digestion and vitamin production (for example, vitamin K, B12, thiamin, and riboflavin; bacteria help produce vitamin C) among other roles.  They help to set up our immune systems when we are young; exposure to infection helps the immune system build up a ‘database’ of information, an armoury that protects us later in life. Healthy humans also carry a number of novel unknown viruses, including bacteriophage (viruses that paralyse a bacterium by infecting it and replicating inside) to known human disease-causing pathogens – the impact of these novel viruses is yet unknown. (Sayer Ji 2021, Roossinck 2015)


Drastic changes within the body (a compromised or weakened immune system, tissue damage or injury, shock, poor diet and so on) may detrimentally affect the intricately balanced eco system of microbes, which may in turn make us sick.  Generally, microorganisms that colonise and co-exist within the body (transiently or permanently) do not impede normal bodily functions.  Some, however, apparently become pathogenic (that is, cause dis-ease), if this balance is disturbed; fewer still are classified as being ‘always pathogenic’ or ‘infective’– one example being rabis virus.  Most microorganisms coexist on and within the body harmlessly.  Indeed, most microorganisms do not cause a single well-defined disease; it is assumed to be far more common for a single bacterium to cause different diseases.  Staphyloccus Aureae (which resides on the nose and on the skin, as well as within soil, air and water), for example, can cause food poisoning or pneumonia or a wound infection.  Meningitis, on the other hand, can be caused by bacteria or viruses or fungi or parasites. Microorganisms are only able to cause disease under specific circumstances or conditions.


Just to clarify a small point before I continue; some authors refer to viruses and bacteria collectively as microorganisms (organism refers to a living thing) while other authors make separate distinction between the virome (consisting only of non-living viruses) and the micro biome (consisting of living bacteria, fungi and archaea – archaea are primitive single-celled organisms).


But really, what is a virus?


Simply, a virus is, apparently, a particle of genetic RNA (assembled in the cytoplasm of a cell) or DNA (constructed in the cell’s nucleus), which is surrounded by a protein coat (capsid) that may or may not be surrounded by a further lipid membrane envelope.


Viruses are not ‘alive’ in the usual sense, because they do not fulfil all the criterion of a living entity (movement, nutrition, excretion, respiration, reproduction, growth and sensitivity); apparently, they ‘host jump’ and borrow energy from cells. For example, they replicate rather than reproduce or divide, and in order to carry out this function they must first enter and tap into the energy and resources of a suitable living host cell; thus, they appear to be parasitic.


Once inside a cell, and after attaching and transferring its genetic material into a host cell, the original virus particle replicates its DNA or RNA and protein cover thousands of times, creating, or rather assembling, new virus particles. This process of replication continues until the cell literally bursts open, expelling the newly formed particles, which then go on to infect or enter other nearby cells, thus perpetuating replication; cell infection or infiltration can occur over a few hours or several days depending on the type of virus.


Ah!  But wait a moment.  There are also other postulations about the nature and role of viruses emerging from the Star Ship Enterprise’s log.


According to Dr Robert Young (2021, 2020), for example, viruses do not invade cells but are, in fact, toxic exudes excreted from cells (produced by the cell); that is, they are waste products finding their way out of the body. They are the expressions of disease (rather than the cause).  Symptoms usually attributed to infection (such as, raised temperature, sweating, excessive mucus (runny nose), diarrhoea, aching muscles, headaches and so on), are, in fact, the means by which the body rids itself of (excretes) toxic waste (this waste also includes debris from bacteria cells).


Others, for example, Dr Tom Cowan, Dr Andrew Kaufmann, and Dr Sam Bailey, suggest that there is no convincing evidence to date that actually proves viruses, or virus particles or fragments, exist; viruses have not been isolated, purified or identified as being distinguishable entities unique from other cellular or microscopic matter or debris.  In the case of COVID19, for example, analysis of the existence and nature of this virus is based on in-silico modelling, where fragments or particles assumed to originate from the virus are assembled in order to create a model of what is assumed to be the whole virus. Indeed, deliberation about this ensues, the jury is still out, opinions are (often controversially) divided (science, after all, is an ever evolving and continual process of investigation and exploration).


Virus particles are assumed to be present among bacteria, exosomes and microscopic helminths found in and around cells – a veritable soup. Perhaps because they are so infinitesimally small, virus particles may easily be confused with exosomes and other similar microscopic and sub-microscopic particles; hence the ensuing debate and mixed opinions about what they actually are (exosomes and viruses apparently carry out similar roles, both carry information, both are ‘messengers’).


Exosomes are discrete expressions, messengers, from cell repair proteins; they are virus-like particles that are indistinguishable from viruses.  Bacteria are the biological breakdown products of cells and, unlike viruses, which are not ‘alive’, comprise of genetic matter. Bacteria behave as ‘scavengers of nature – they reduce dead tissue to its smallest element’ – they clean up the territory. Helminths are worm-like parasites.


So, virus particles apparently act as messengers, and are excreted from one part of the body, or environment, to another (de Sousa 2020).  Both viruses and exosomes are information delivery systems, which is one of the reasons they may be confused with each other. However, apparently, exosome’s are non-specific information messengers and can be absorbed by any cell, whereas viruses are highly selective and will only target specifically designated cell receptors (like a key in a lock); for example, in the case of the SARS-CoV-2 virus, it is the ACE2 receptor expressed in the lungs and other tissues of the respiratory and vascular system this virus ‘locks’ into.


Dr. Zach Bush (2021, 2020), also supports the above notion.  He describes viruses as being non-living vectors, or carriers, of genomic information secreted from bacteria, fungi, multicellular plant life, humans and animals, which are released, or activated, in response to stressors; thus, signalling need for adaptation (to regenerate or detox, for example) to environmental threats or changes. If life is peaceful, Bush explains, and there is no immediate threat or disturbance, then there is little need for the expression of virus exudation from the body. Dis-ease is a consequence of stress, which can have various causes; for example, environmental pollution, chemical toxins in foods (herbicides, pesticides, chemical additives etc.) and household products, poor living and working conditions, an impending sense of scarcity and threat, and so on.


Thus, viruses convey new information to the body (or organism) to aid its adaptation.  In other words, we are not in conflict with the virome, the virome does not exist to attack us, but to inform and assist our regenerative and adaptive capacity within an ever-changing environment. The micro biome plays its own role. New science, for example, says Bush, reveals how the micro biome guides our health and ‘functions as the life-giving soil within our gut and internal organs, and is at the core’ of our ability to thrive.  Thus, we survive by virtue of the intelligence of nature, which, saturates, connects and communicates with all life through the micro biome. The internal endogenous (of internal origin) and external exogenous (of external origin) virome and micro biome are intrinsically interconnected.


Germs are nothing, terrain is everything, Robert Young affirms (2020). If the terrain is compromised and overburdened with toxins, or otherwise stressed and/or weak, then things may go awry. The equilibrium of the micro biome is finely balanced. A clean terrain is the foundation of healthiness (‘cleanliness is next to godliness’ after all, Young reiterates). Viruses, exosomes and bacteria are products, or helpers, of the body’s attempt to cleanse, repair and maintain healthy equilibrium and function.


We do not catch dis-eases. We build them with what we have to eat, drink, think, fear, and believe them into existence. We work hard at developing our diseases. We must work just as hard at restoring health.


The presence of germs (viruses, bacteria, yeast, mould and their associate exotoxins, endotoxins and mycotoxins – acids) does not constitute the presence of sickness or disease. Germs or bacteria have no influence, what so ever, on living cells – they flourish as [cleansing] scavengers at the site of disease.  (Young 2020)


Whichever way you view it, it seems to make sense that the condition of the body’s terrain contributes in some way to resilience and functional equilibrium.  According to Young, a body filled with unclean toxins and waste particles indicates decay, which initiates bacteria to ‘clean up’ the territory; bacteria act as ‘scavengers of nature – to reduce dead tissue to its smallest element’.  Caught at the scene of the ‘crime’, bacteria are consequently assumed to be the ‘guilty’ party.  Whether bacteria or viruses cause illness or are expressions of dis-ease remains debatable; there are numerous theories, yet still, so far, little ‘hard’ evidence.  As Doctor Tom Cowen (2021) reminds us, no one to-date has actually, in truth, isolated a virus particle; those viruses that are identified are, in fact, computer generated (in silico) creations based on uncertain or unclear evidence (see here)


Sayer Ji explains, in his fascinating book Regenerate: unlocking your body’s radical resilience through the new biology (2020 p 52-3):


Our bodies resemble plants in that our susceptibility to pests, or opportunistic infections, escalates when we aren’t provided with the proper inputs, such as when our ecosystems are in a state of disharmony, when our microbial soil is depleted, and when our micronutrient status is compromised. The modern pressures of a sedentary lifestyle; pharmaceutical drugs; occupational stress; ultra-processed foods; electromagnetic pollution; man-made toxicants; and circadian rhythm-disrupting blue-light cause our micro-diversity to suffer, in turn opening the door to sickness.


When we malign all bacteria as microorganisms to be feared and eradicated, we indiscriminately target commensal and virulent microbes alike. We do so with antibiotics, hand sanitizers, chemical cleaning agents, triclosan-laden antibacterial soaps, and gut disrupting pharmaceuticals like acid-blocking drugs and over-the-counter pain relievers. While they are purportedly designed to heal, these prescriptions inevitably destroy the system that has evolved to protect us.


Clearly, our health and resilience are determined by multiple factors.  Once aware of these factors, we can chose to take steps to balance, maintain and manage our bodily terrain. In doing so, we may discover that we are not simply the random victims of these invisible inhabitants. When we proactively take care of our body (keeping it toxin free, clean and nourished, observing what we absorb into our bodies – fresh nutritious foods, fresh air, clean water, positive thoughts and emotions, optimism and positive community) we also provide a thriving healthy symbiotic territory for the trillions of invisible microbes and particles that inhabit our body and surrounding environment.  Consequently, we are more inclined toward resilience and resistance to disturbance and pathogenic invasion; and more able to readily healthily adjust and rebalance, to move through life unimpeded by illness and disease, or to recover quickly when we are infected or out-of-balance.  All emotions (including thoughts), positive and negative, are valuable, or useful, indicators or expressions of our ‘state of being’, however, like a river, they are meant to flow, wash through us; indeed, it appears that stagnation (whether emotional or physical) precedes dis-ease. (Godfrey 2022)



This article has explored the loss of sense of smell caused by colds, ‘flu, and more recently COVID-19, and infection, and the application of essential oils to aid recovery.


Exploring what a virus is (or is not) sheds some light on how to address the potential consequences of infection.  Clearly the science is not settled; there are a number of postulations about the nature and role of viruses, exosome’s, bacteria and other nanoparticles,


Indeed, we are surrounded by microbes and various micro-particles, including bacteria and fungi with which we share a symbiotic and, generally, healthy and supportive relationship.  A healthy immune system actually works in collaboration with viruses and other commensal microbes to maintain healthy internal equilibrium.


COVID-19 is apparently a novel virus with mild to severe symptoms (debate ensues with regard to its origin and structure – the virus has not been isolated in the usual way, so its specific identity is unclear; a computer-generated in-silico model of the virus, based on assumed parts of the virus, is currently applied to determine infection). One of the less severe, but none-the-less, distressing symptoms of this and other ‘flu and cold corona viruses (whether present as an infection or outfection) is loss of the sense of smell. Recent research indicates that essential oils have a potentially significant role to play as aids to recovery of anosmia (loss of the sense of smell)


While colds and ‘flu, and other corona viruses, may ‘take down’ the ability of olfactory neurons to register scent molecules, scent molecules are still able to instigate neural responses that relay messages to the limbic system within the brain; some scent molecules traverse the epithelium at the roof of the nasal cavity and enter the brain.  The process of smelling a scent may evoke memories, and initiate related feelings and sensations, even stirring imagination, in a way that in turn may begin to gradually re-awaken or stimulate the sense of smell.  Essential oil molecules aid tissue regeneration and repair, therefore, may also support healing of olfactory nerves damaged instigated by corona viruses and infections.


The four essential oils selected for the ‘smell training’ exercise (clove, eucalyptus globulus, lemongrass and rose) express a diverse and complex range of scent nuances between them, yet each essential oil exudes its own unique and distinctive odour quality. These scents also express odour qualities that correlate with three of the four basic tastes (sweet, bitter and sour). Applying these essential oils to sensually stimulate and heal tissues damaged by infection and inflammation, forty five per cent of smell training participants regained their sense of smell (Hopkins 2021, Hummel 2018, 2009)  Along with their sensual qualities (or ‘scentual’), these oils also have antimicrobial, anti-viral and anti-inflammatory properties, and evoke various psycho-emotional responses that might alleviate some of the symptoms of colds and ‘flu and similar corona viruses, such as fatigue, depression, brain fog and lack of concentration, while also staving residual infection and averting further spread.


You will find detailed information in my award-winning books (your go-to reference guides) about related chemistry, botany and the various properties and qualities of individual essential oils, how to create remedies and blends and how apply them safely and effectively: Healing with Essential OilsEssential Oils for the Whole Body, and Essential Oils for Mindfulness and Meditation, published by Healing Arts Press, Inner Traditions USA.


Russ, B., Dyall-Smith, M. (2007) Virus-host interaction in salt lakes. Current Opinion in Microbiology 10(4):418-424.

Le Romancer, M., Gaillard, M., Geslin, C., Prieur, D. (2007) Viruses in Extreme Environments. Environmental Science and Bio Technology.

Rohwer, F., Prangishvili, Lindell, D. (2009) Roles of viruses in the environment. Society for Applied Microbiology.

Virgin, H. (2013) Interactions between the mammalian virome, disease susceptibility genes, and the phenome. NASEM Health and Medicine Division: You Tube Lecture.

Ji, Sayer (2020) Regenerate: unlocking your body’s radical resilience through the new biology, Hay House, London p 52-3

Roossinck, M. J. (2015) Move over bacteria! Viruses make their mark as mutualistic microbial symbionts. Journal of Virology, 2015; JVI.02974-14 DOI: 10.1128/JVI.02974-14

Young, R. O. PhD. (2021) Disease, germs, viruses and vaccinations. Interview with Sasha Stone (interview removed from You Tube) / alternative source re virus information: Lies, more lies and damned lies Interview with Sacha Stone, Robert Young and Judy Mikovits (interview removed from You Tube)

Young, R. O. PhD. (2020) Do Germs Like Corona Virus Cause Disease?

Sousa, A (sourced 2021) Viruses: Genetically encoded messages for communication between individuals.  Open Access Text.

Bush, Z. (2021) The last 30 years of microbiome research necessitates a radical shift in our model of human health.

Bush, Z. (2020) Knowledge – The Virome. You Tube Interview.

Roosinck, M. J. (2015) Plants, viruses and the environment. Virology (Elsevier) vol 479-480 p 271-277.

Schrader, J. (2015) Cytokines and Antibodies. Biomedical Research Centre, University of British Columbia.

de Silva, J. K. R. (2020) Essential Oils as Antiviral Agents, Potential of Essential Oils to Treat SARS-CoV-2 Infection: An In-Silico Investigation.   International Journal of Molecular Science 21(10): 3426.

Nazaro, F., Fratianni, F., Martino, L. D., Coppola, F., De Feo, V., (2013) Effects of Essential Oils of Pathogenic Bacteria. Pharmacueticals (Basel) 6(12): 1451-1474.

Vasey, C. (2018) Natural Antibiotics and Antivirals: 18 Infection-Fighting Herbs and Essential Oils: Healing Arts Press, Rochester, Vermont USA

Sander, G., Heckman, M., Weghuber, J. (2020) Immunomodulatory Activities of Selected Essential oils. Biomolecules 10(8): 1139.

Han, X., Parker, T. L., Dorsett, J. (2017) An essential oil blend significantly modulates immune responses and the cell cycle in human cell cultures. Taylor and Francis on line.

Kuriyama, H., Watanabe, S., Nakaya, T., Shigemori, I., Kita, M., Yoshida, N., Masaki, D., Tadai, Toshiaki, Ozasa, K., Fukui, K., Imanishi, J. (2005) Immunological and Psychological Benefits of Aromatherapy Massage. Evidence Based Complementary and Alternative Medicine 2(2): 179-184.

Williams, S. C. P. (2014) Human Nose can Detect a Trillion Cells. Brain Behaviour and Biology. Science

Godfrey, H. D. (2022) Healing with Essential Oils: The Antiviral, Restorative, and Life-Enhancing Properties of 58 Plants. Healing Arts Press, Rochester, Vermont USA

Godfrey, H. D. (2019) Essential Oils for the Whole Body: The dynamics of topical application: Healing Arts Press, Rochester, Vermont USA

Leffingwell, J. C. (sourced on line 11th February 2021) Olfaction: a review. Leffingwell and Associates.

Venkatesan, P. (2021) Nice Guideline on Long COVD. The Lancet, Respiratory Medicine, vol. 9 issue 2.

N, W., Yang, X., Yang, D., Bao, J., Li, R., Xiao, Y., Hou, C., Wang, H., Liu, J., Yang, D., Xu, Y., Cao, Z., Gao, Z. (2020) Role of ngiotensin-converting enzyme 2 (ACE2) in COVID-19. Critical Care no. 442.

Rebholz, H., Braun, R. J., Ladage, D., Knol, W., Kleber, C., Hassell, A. W. (2020 Loss of Olfactory Function – Early Indicator for COVID-19, Other Viral Infections and Neurodegenerative Disorders. Frontiers in Neurology. Dementia and Neurodegenerative Diseases.

Damm, M., Pickart, L. K., Reimann, H., Burkert, S., Goktas, O., Haxel, B., Frey, S., Charalampakis, I., Beule, A., Renner, B., Hummel, T., Huttenbrink, K-B. (2014) Olfactory Training is helpful in post-infectious olfactory loss: a randomized controlled multicenter study. Laryngoscope 124(4):826-31.

Hummel, T. (2018) A simple flu, and simple infection: how effective is smell training at curing infection? BCC News interview.

Hummel, T., Rissom, K., Redden, J., Hahner, A.,Weidenbecher, M., Huttenbrink, K-B. (2009) Effects of Olfactory Training in Patients with Olfactory Loss. Laryngoscope.

Hummel, T., Rissom, K., Redden, J., Hahner, A.,Weidenbecher, M., Huttenbrink, K-B. (2009) Effects of Olfactory Training in Patients with Olfactory Loss. Laryngoscope.

Asif, M., Saleem, M., Yarseen, H. S.’ Zarzour, R. A. (2020) COVID-19 and therapy with essential oiks having anti-viral, anti-inflammatory, and immunodulatory properties. Inflammopharmacology 28:1153-1161. file:///Users/Heather/Downloads/Asif2020_Article_COVID-19AndTherapyWithEssentia.pdf

Shi, Y., Wang, Y., Shao, C., Huang J., Gan, J. Huang, X., Bucci, E., Piacentini, M., Ippolito, G., Melino, G. (2020) COVID-19 infection: the perspectives on immune responses. Cell Death and Differentiation 27 1451-1454.

Kumar, J. K. S., Vani, M. G., Wang, C-S., Chen, C-C., Chen, Y.C., Lu, L-P., Haung, C-H., Lai, C-S., Wang, S-Y. (2020) Geranium and Lemon Essential Oils and Their Active Compounds Downregulate Angiotensin-Converting Enzyme 2 (ACE2), a SARS-CoV-2 Spike Receptor-Binding Domain, in Epithelial Cells. Plants (Basel) 9(6): 770.

Zuo, M (2020) Vitamin C deployed in big doses to help treat coronavirus patients. Southern China Morning Post, China/Society 28th March 2020.

Hemila, H. (2003) Vitamin C and SARS coronavirus; Journal of Antimicrob Chemother, 56:6 p1049-1050.

Kakodkar, P., Kaka, N., Baig, M.  N. (2020) A Comprehensive Literature review on the Clinical Presentation, and Management of the Pandemic Coronovirus Disease 2019 (COVI-19). 12th April, 12(4): e7560.

Ayyadurai, S., Dr. MIT PhD (2020) Coronavirus is the right time to discuss immune health: You Tube

Cahill, Dolores Prof. (2020) Debunking the Narrative,

Gao, T., Ding, X., Chai, J., Zhang, Z. (2017) The Influence of Resilience on Mental Health: The Role of General Wellbeing. International Journal of Nursing Practice 23(3)

Conversane, C., Rotondo, A, Lensi, E., Vista, O. D., Arpone, F., Reda, A. M. (2010) Optimism and Its Impact on Mental and Physical Well-Being. Clin. Pract. Epidemiol Ment. Helath 6: 25-29

Feuer, S. (2019) How I Brought My Nose Back to Life. Narratively. Pocket Worthy.