Is there a risk for transmission of Covid infection to others even after recovery?
As millions of people are recovering from COVID-19, an unanswered question is the extent to which the virus can “hide-out” in seemingly recovered individuals. A chronic or persistent infection continues for months or even years, during which time virus is being continually produced, albeit in many cases at low levels. Frequently these infections occur in a so-called immune-privileged site.
There are a few places in the body that are less accessible to the immune system and where it is difficult to eradicate all viral infections. These include the central nervous system, the testes and the eye. It is thought that the evolutionary stage to having an immune-privileged region is that it protects a site like the brain, for example, from being damaged by the inflammation that results when the immune system battles an infection.
An immune-privileged site not only is difficult for the immune system to enter, it also limits proteins that increase inflammation. The reason is that while inflammation helps kill a pathogen, it can also damage an organ such as the eye, brain or testes. The result is an uneasy truce where inflammation is limited but infection continues to fester. But there is another way that a virus can hide in the body and reemerge later.
There are a few places in the body that are less accessible to the immune system and where it is difficult to eradicate all viral infections. These include the central nervous system, the testes and the eye. It is thought that the evolutionary stage to having an immune-privileged region is that it protects a site like the brain, for example, from being damaged by the inflammation that results when the immune system battles an infection.
An immune-privileged site not only is difficult for the immune system to enter, it also limits proteins that increase inflammation. The reason is that while inflammation helps kill a pathogen, it can also damage an organ such as the eye, brain or testes. The result is an uneasy truce where inflammation is limited but infection continues to fester. But there is another way that a virus can hide in the body and reemerge later.