Any virus, however dangerous, is nothing without its host cell, which it needs to multiply. With the primary intention of spreading itself, it would, of course, be counterproductive for a virus to kill its host. In any case, a virus contains foreign biological information that activates the natural control mechanisms within the human body.
The gateway for SARS-CoV-2 is the enzyme ACE2, which is expressed in many cells, such as in the heart’s muscle and vascular cells, in the kidneys, the intestines and in the lungs . The main entrance for the virus, which is mainly transmitted by droplet infection, is in the air that we breathe. However, the lungs are far from sterile :
It has only been known for a few years that bacteria, fungi and viruses also live in the lungs – actually in all humans. The totality of these microorganisms is called the microbiome. Scientists are still investigating the function of this lung microbiome in detail.
Reports in the media of current Covid-19 cases mainly attribute pneumonia to the new virus. Given that the type of microbes – viral, bacterial and fungal – and volume will differ in each patient’s lung microbiome, by determining the pre-existing components that ‘may’ differentiate the individual response to Covid-19 would that provide a more accurate overview of the interactions and interconnection between the virus and its human host?
Research teams at the Charité developed a model of human lung tissue that can simulate essential characteristics of pneumonia. They first infected the tissue with influenza viruses and then with pneumococci (bacteria) to simulate severe pneumonia. Due to their structural differences, viruses and bacteria are rendered harmless by the immune system in various ways :
“We have been able to demonstrate that the anti-virus immune response is harmful to the subsequent control of a bacterial infection with pneumococci.”
This research suggests that the overlay of the viral infection by Sars-CoV-2 with a bacterial infection may be the cause of the life-threatening pneumonia observed in Covid-19. So far, no information has been made public about other factors, such as influenza viruses, whose occurrence would not be uncommon this winter.
Interestingly, new study results from Prof. Christian Drosten et al suggest that in the case of SARS-CoV-2 there can also be cross-immunity from previous infections with other corona viruses: His team examined T-cells, i.e. blood cells that serve the immune defence. T-cells of already cured COVID-19 patients and of patients who have not yet been infected were examined :
“Surprisingly, it was found that 34 percent of the patients had reactive T-cells although they had never had contact with the SARS 2 virus”
Therefore, in our Corona research project, participants’ data regarding antibodies and previously suffered diseases will be collected.
The role of host and environment
Whole branches of science research the interplay of microbes including viruses with the ecosystem and the individual host. Awareness rises that:
- Viruses have a positive function inside the ecosystem
- The damage viruses create in an individual is dependent on factors of the host’s internal and external environment
The Intra-Dependence of Viruses and the Holobiont :
To determine viral involvement within the holobiont, it is necessary to identify and elucidate the function of viral populations in symbiosis with the host. Viral metagenome analyses identify the communities of eukaryotic and prokaryotic viruses that functionally associate within a holobiont. Similarly, analyses of the host in response to viral presence determine how these interactions are maintained. Combined analyses reveal how viruses interact within the holobiont and how viral symbiotic cooperation occurs.
Cytopathic effects: virus-modulated manifestations of innate immunity? 
The capacity to injure infected cells is a widespread property of viruses. Usually, this cytopathic effect (CPE) is ascribed to viral hijacking of cellular resource sto fulﬁll viral needs. However, evidence is accumulating that CPE is not necessarily directly coupled to viral reproduction but may largely be due to host defensive and viral antidefensive activities. A major part in this virus–cell interaction appears to be played by a putative host-encoded program with multiple competing branches, leading to necrotic, apoptotic, and, possible ,other types of cell suicide. Manifestations of this program are controlled and modulated by host, viral, and environmental factors.
This research suggests that we humans can prevent or reduce the damage triggered by any given viral infection by monitoring and adjusting the factors that contribute to the grow-ground of this infection, as well as to the adversity of our reaction to it.
Corona and influenza viruses are present all year round, but typically lead to cases of cold and influenza mainly in the winter season  when sun exposure and thereby vitamin D-levels are lowest, and when the lower temperature outside seems to promote viral activity. This seems to also apply for SARS-CoV-2 :
The “virus is highly sensitive to high temperature”, which could prevent it from spreading in warmer countries, while the opposite appeared to be true in colder climates.
When viruses have a vital part in the ecosystems and their balance, it is no solution to change the climate in order to try to prevent their spreading, although one could think of hyperthermia as a preventive or therapeutic approach of treating cases of Covid-19. However, certain practices and lifestyle choices have proven to prevent individual infection or disease.
These vitamins, minerals and immunomodulators can be included in one’s diet:
- Vitamin C through fresh fruit and vegetables, lactobacteria or dietary supplements 
- Vitamin D from sunlight, fatty fish or as a dietary 
- Vitamin A from liver, sweet potatoes, carrots, along with some fat 
- Iron and zinc from offal, egg and dairy products, or dietary supplements 
- Immunomodulators with medical herbs such as Echinacea, Baptisia, Thuja, Eleutherococcus, Pelargonium and Uncaria  
Further reading: Immunomodulating herbs
Interestingly, there seem to be natural dietary supplements that even exceed vaccination in efficiency and safety :
Colostrum, both in healthy subjects and high-risk cardiovascular patients, is at least 3 times more effective than vaccination to prevent flu and is very cost-effective.
In addition to diet, there are more proven ways in which we can support our immune system:
- Sufficient and restful sleep 
- Hardening, Kneippism and hydrotherapeutics  
- Mental training and meditation 
Therefore, participants in our Corona research project will be given the choice to strengthen their immune system naturally with these measures.
Psychoneuroimmunology – the internal environment
Our moods—and sense of connection—have a profound effect on our white blood cells (immune cells, such as B cells, T cells, natural killer [NK] cells, and macrophages). The feelings of stress and social isolation are some of the biggest immune “downers” out there. 
Stress hormones, such as adrenaline (epinephrine) and cortisol, weaken immune function. Psychological stress (which can be generated by the media in the Covid-19 situation) has been associated with an increased risk of acute respiratory illness. 
The setting of our research project as a “Corona retreat” (and a social event) will address these findings and attempt to minimize stress and fear. We can record general and individual stressors, and teach the participants how to reduce the impact.
Typical examples how to reduce the feeling of stress are:
- Meditation and breathing methods 
- Laughter and joy (“Laughter Yoga”) 
- Physical activity 
- Energy Psychology methods such as EFT/Tapping 
For the effect of EFT/Tapping on Covid-19, there is an example of a person from the “Diamond Princess” cruise who had a dramatic course of the disease, and managed it with the help of this technique.
Further reading: Psychoneuroimmunology
 Deutsche Apotheker Zeitung 2020.03-12 – Mit löslichem ACE2 gegen COVID-19
 Techniker Krankenkasse 2019-03-14 – Mikroorganismen in der Lunge: Forschungspotenzial in der Atemwegsmedizin
 Press release Charité 2017-07-13 – Forscher heben Immunblockade gegen Bakterien auf
 NDR Coronavirus-Update 2020-04-24 – (35) Vielversprechende Impfstudie aus China
 Frontiers in Immunology 2017-11-09 – The Intra-Dependence of Viruses and the Holobiont
 MP Chumakov Institute of Poliomyelitis and Viral Encephalitides 2012-12-20 – Cytopathic effects: virus-modulated manifestations of innate immunity?
 Medscape 2019-07-30 – Rhinovirus (RV) Infection (Common Cold)
 South China Morning Post 2020-03-08 – Coronavirus ‘highly sensitive’ to high temperatures, but don’t bank on summer killing it off, studies say
 MedizInfo – Vitamin C
 Focus 2010-03-08 – Vitamin D Schlüsselhormon des Immunsystems
 Wikipedia – Vitamin A
 Focus 2015-06-02 – Zink stärkt Immunsystem, Haut und Nägel
 Deutsches Ärzteblatt 42/1997 – Pflanzliche Immunmodulatoren vermindern Streßreaktionen
 Österreichische Gesellschaft für Phytotherapie – Pflanzliche Immunmodulatoren
 Cesarone et al 2007-04-13 – Prevention of influenza episodes with colostrum compared with vaccination in healthy and high-risk cardiovascular subjects
 Hannoversche Allgemeine 2019-02-13 – Wie Schlaf das Immunsystem stärkt
 Focus 2009-08-14 – Kneipp-Therapie Wasser als Heilquelle
 Matthijs Kox et al 2014-05-20 – Voluntary activation of the sympathetic nervous system and attenuation of the innate immune response in humans
 Cleveland Clinic 2018-01-25 – How Mindfulness Training Can Boost Your Immune System
 American Psychologocal Association 2006-02-23 – Stress Weakens the Immune System
 Sheldon Cohen et al – The New England Journal of Medicine 1991-08-29 – Psychological Stress and Susceptibility to the Common Cold https://www.nejm.org/doi/full/10.1056/NEJM199108293250903
 Harry Mills et al – Gulf Bend Center – Methods of Stress Reduction
 Mohsen Yazdani et al – Iranian Journal of Nursing and Midwifery Research 2014-02 – The effect of laughter Yoga on general health among nursing students
 Harvard Health Publishing – Exercising to relax
 Donna Bach et al – Journal of Evidence-based Integrative Medicine 2019-02-19 – Clinical EFT (Emotional Freedom Techniques) Improves Multiple Physiological Markers of Health