Many states have recently started reopening their economies, which could be the source of some juvenile biases, said Natalie Dean, an infectious disease epidemiologist in Florida, where new cases are reaching record levels. People in their twenties and thirties have returned to bars and beaches; employees of working age have resumed work that cannot be done at home.
“We know this risk is high,” said Dr. Dean. “We hear a lot of cluster reports related to these places” as they open.
At the same time, older adults, as well as those with underlying health conditions that worsen Covid-19, may be more cautious about exposure, said C. Brandon Ogbunu, computational biologist and disease disease ecologist. ‘Yale University. “At first, this disease ravaged older populations with such aggression,” he said. “This is perhaps where the message was most strongly felt. “
In addition, nursing homes and other facilities that house vulnerable populations can work harder to protect their residents, said Dr. Dean. In general, “We now have a better set of tools to keep our communities safe,” he said. “More and more people are wearing masks. We are better at disinfecting things. ”
Of course, “young people don’t live in isolation,” said Dr. Bell. They always mix with older members of the population, which could lead to transmission events that have not yet occurred.
Experts may not be sure, but behaviors such as wearing a mask, physical remoteness, and hygiene can also reduce the dose of coronavirus that people encounter in the general population, said Dr. Dean. The amount of virus that individuals carry can influence the severity of their symptoms. But so far, there is no evidence that this dynamic is contributing to the decline in the death rate in the United States.
There is also no indication that the death rate is lower because the coronavirus itself has become less deadly, said Dr. Ogbunu. The mutation is a normal part of the evolutionary trajectory of any virus, but these genetic changes are often of no consequence.