Why Some People Get Terribly Sick from COVID-19
This
Scientific American article is worth a read (BBM).
"What determines if someone gets desperately ill from the disease that is ripping its way across the planet? You are likely familiar with the broad categories of people who face greater risk:
older individuals, men, those who have certain chronic conditions, and—notably in the U.S. and England—people of color. But researchers are looking deeper into these groups to determine the underlying roots, both biological and social, for their vulnerability. Investigators are relating age-related risk to the ways that the immune system changes over the years, for example, and examining male-female differences in immune responses. Some scientists are probing for genetic variations that might raise susceptibility. Others are highlighting the social, environmental and economic factors that elevate risk, including racism."
And since we've been discussing greater risk of old people dying, here is an excerpt regarding age and risk of severe illness and death from COVID (BBM):
"
Age is probably the single biggest determinant of how sick someone gets from the coronavirus. In China, where the pandemic began, the average person with a confirmed infection had a 2.3 percent chance of dying. But for people between 70 and 79, it was 8 percent, and for those older than 80, it was 14.8 percent.
In New York City, nearly half of confirmed deaths were among the elderly, aged 75 and older, and another quarter were among those aged 65 to 74. An
analysis of 17 million people in England, published in
Nature in July, concluded that patients older than 80 were at least 20 times more likely to die of the infection than those in their 50s.
“Age was our biggest predictor of outcome,” says Mangala Narasimhan, regional director of critical care at Northwell Health, the largest health care provider in the New York City area, and a co-author of a report in
JAMA on the
characteristics of 5,700 hospitalized COVID-19 patients. The dense concentration of elderly people in nursing homes, where infections can spread quickly and prevention is often inadequate, is clearly one reason for this correlation. But biology is another factor, particularly the aging of the immune system.
As the decades roll by, the human body becomes less effective at fighting infections.
This decline is one reason why roughly 90 percent of U.S. deaths from influenza are among people aged 65 and older and why vaccines are less protective in the elderly. Basically, our defensive cells become thinned out in number and variety. And like old warriors, they become more geared toward fighting yesterday’s battles with familiar enemies than tackling something new, such as the latest flu strain or the novel coronavirus."
Also:
The CDC says that 8 out of 10 COVID-19-related deaths reported in the United States have been among adults aged 65 years and older.
