Human beings have co-evolved with a myriad of pathogens. Gladly. We co-exist and live with thousands of species of viruses, bacteria, fungi. Many viruses embed and dis-embed their genetic material into ours in a natural way. In fact, our own DNA contains ancient viral sequences of genetic material which we will pass on to the next generation. More than 100.000 trillion microorganisms inhabit our guts and influence our lives, for the better. The air around us has quadrillions of bacteria and viruses: millions of them floating in each cubic meter. We breathe in a few hundred thousand viruses every minute. Most of them are neutral to us, but part of them are human pathogens: they can cause infections to humans. And yet, we get such infections very rarely. Say thanks to the immune system: the human immune cells can identify pathogens and neutralize them, either by direct attack or by synthesizing antibodies complementary to each available pathogen particles (antigens); and there are more than one quintillion unique types of antibodies.
The immune system’s function is due to its unique genetic/molecular machinery, capable of taking advantage of genetic rearrangements. But this is not enough; its function is also dependent on the interactions between our body and microorganisms. This can be proven in at least two ways.
On one hand, we are the end product of the “survival of the fittest” evolution of mankind, while being put to the same evolutionary tests over and over. Our genes are as diverse as our ancestors’ relations were inter-specific. Our immune systems were also shaped by the pathogens our ancestors faced: tuberculosis has been with us for at least 500,000 years and exposure to malaria led to drastic genetic changes that allowed those exposed to the pathogen to resist the adverse effects of the disease. Each interaction of our direct ancestors with microbes made our immune systems stronger and explain why different human populations respond differently to the same pathogen.
On the other hand, our immune system relies on us interacting with various types of microorganisms. Lack of proper exposure, especially early in life, to certain microorganisms or allergens has negative health effects. Which is why evidence piles up showing C-section babies, or those fed with formula instead of breast milk, show weaker health and susceptibility to infection by harmful pathogens.
Modern science has shown us what is needed for proper stimulation of the immune system. We now know how vitamin D deficiency or other nutritional anomalies, link to weakened immune systems. We know that sun exposure, proper diet or regular exercise make us stronger in the same regard. We know which populations are more susceptible to certain diseases and we also know that preventing is better than treating. For those that need treatment, there is a wide range available for almost any type of infection.
But this is not enough. Somehow, a new disease of unknown origin (named covid), having a fatality rate among healthy people lower than the risk of dying from a car accident, prompted some people to tell other people to distance themselves and wear a barrier to their very own breaths, the face masks. For about 1 to 2 years, many people put themselves at shelter from the natural mechanisms acting to our very own survival of the species. At the time of this writing, face masks, social distancing, or any other types of unnatural aversion contra life in all its forms, are still mandatory in certain parts of the world. No one kind of scientific study can properly evaluate the future impact of such measures. Only time will tell. In the meantime, we will create 100% efficacy face shields and await for the next viral species to do its thing. God forbid its mortality rate be higher, or face-mask holocaust may ensue.