Many viral infections may linger and “hide out” in your body after you have seemingly recovered from the initial infection. Currently, millions are recovering from COVID-19 infections and we do not know to what extent this virus can linger on in your body.
When viruses linger, they may lead to more spreading of the disease and prolonged symptoms. A chronic or persistent infection continues for months or years, during which time the virus is being continually produced, albeit in many cases at low levels.
Frequently, these infections occur in a so-called immune privileged site, where it is less accessible to the immune system and the body has difficulty in trying to eradicate it. Such immune privileged sites include the central nervous system (brain), the testes and the eye.
A latent infection occurs when the virus is present within an infected cell but dormant and not multiplying. The latent virus may integrate into the human genome – as does HIV. A latent virus can reactivate and produce infectious viruses, and this can occur months to decades after the initial infection.
The best example of this is chickenpox, which although seemingly eradicated by the immune system can reactivate and cause herpes zoster (shingles) decades later.
The bottom line is, “To be infected with a virus capable of producing a latent infection is to be infected for the rest of your life.”
Herpes viruses are by far the most common viral infections that establish latency. Herpes viruses include not only herpes simplex viruses 1 and 2 – which cause oral and genital herpes – but also chickenpox. Other herpes viruses, such as Epstein Barr virus, the cause of mononucleosis, and cytomegalovirus, which is a particular problem in immunodeficient individuals, can also emerge after latency.
Survivors of Ebola have been documented with persistent infections in the testes, eyes, placenta and central nervous system. Retroviruses, such as HIV, which causes AIDS, are another common family of viruses that establish latency but by a different mechanism than the herpes viruses. Viruses that establish latency in humans are difficult or impossible for the immune system to eradicate.
Fortunately, as far as we now know, coronaviruses do not establish a latent infection. However, recovery from COVID-19 is delayed or incomplete in many individuals, with symptoms including cough, shortness of breath and fatigue. The new coronavirus can also infect the fetus via the placenta. Finally, the new coronavirus is also present in the blood and the nasal cavity and palate for up to a month or more after infection.
COVID-19 can infect immune privileged sites and result in chronic persistent – but not latent – infections.
In the America that I love, it is too early to know the full effects of COVID-19.