The last few months have been rife with new discoveries about the COVID- 19 infections. A mystery that remains is why a large number of infected people stay entirely asymptomatic or only mildly symptomatic, while many others experience the most virulent, life-threatening form of the infection. Although it is clear that those with pre-existing comorbidities are worse affected by the virus, the high variability of symptom severity in otherwise healthy individuals is intriguing.
While researching this topic, I chanced upon an interesting paper by a scientist at IISER Mohali. The paper examines whether the hygiene hypothesis applies to COVID- 19 susceptibility. The hygiene hypothesis, which has been around for some years, lends an explanation for the increasing incidence of autoimmune and allergic disorders in the developed world.
According to the hypothesis, limited exposure to microorganisms due to an extremely sterile environment in the early period after birth can derail the innate immune system. Innate immunity is the body’s first generalized response (not geared to target a specific infection) to any microbial or pathogenic invasion. A particularly sterile environment after birth fails to adequately equip the infant’s immune system to respond effectively at later stages.
The paper I mentioned examines the risk of contracting to COVID-19 in light of the hygiene hypothesis. The immune response to an infectious disease like COVID-19 has to do with the conditions under which the individual’s immune system has matured. There is sufficient data from the WHO and from John Hopkins University to indicate that those living in conditions that are not particularly hygienic are typically less affected by severe diseases.
This may be a reason why Dharavi in Mumbai had a lower rate of the severe COVID-19 infections, despite the densely packed residences and compromised standards of hygiene. Incidentally, India’s COVID-19 fatality rate is relatively lower than that of other countries, and this may have something to do with our overall hygiene conditions. Of course, none of this is cited to suggest that we should no longer wash our hands, or sanitise contaminated surfaces.
All the prescribed precautions to prevent COVID-19 must be followed strictly. In terms of practice, I find that the middle path works best for most things related to food and health. Ancient Indian scriptures have always hailed the virtues of following the middle path. Overdoing anything, even a good thing, has repercussions. To give you a simple illustration, if you eat green leafy vegetables (which, by itself, is a great thing) all day while neglecting other foods, you are bound to face a protein deficiency or a micronutrient imbalance. Moderation and balance, therefore, are key. For the immune system to develop at its peak potential, stimulation to remain active may be a good thing. This is why a sterile environment during the early years may not be the answer.
NEELANJANA SINGH
Nutrition Therapist & Wellness Consultant