‘Asymptomatic cases are not unique to Covid-19. They occur with the regular flu, and probably also featured in the 1918 pandemic, according to epidemiologist Neil Ferguson of Imperial College London. But scientists aren’t sure why certain people weather Covid-19 unscathed. “That is a tremendous mystery at this point,” says Donald Thea, an infectious disease expert at Boston University’s School of Public Health...
‘Disease tolerance is the ability of an individual, due to a genetic predisposition or some aspect of behavior or lifestyle, to thrive despite being infected with an amount of pathogen that sickens others... At least 90 percent of those infected with the tuberculosis bacterium don’t get sick. The same is true for many of the 1.5 billion of people globally who live with parasitic worms called helminths in their intestines...
‘...there are countless disease tolerance pathways. “Every time we figure one out, we find we have 10 more things we don’t understand,” King says. Things will differ with each disease, he adds, “so that becomes a bit overwhelming.”
‘Nevertheless, a growing number of experts agree that disease tolerance research could have profound implications for treating infectious disease in the future. Microbiology and infectious disease research has “all been focused on the pathogen as an invader that has to be eliminated some way,” says virologist Jeremy Luban of the University of Massachusetts Medical School. And as Ayres makes clear, he says, “what we really should be thinking about is how do we keep the person from getting sick.”
Read here (Scientific American, August 25, 2020)
