New research has found that people with a SARS-CoV-2 infection who are asymptomatic carry just as much virus in their throats, lungs, and noses as those who have symptoms. Some experts believe that asymptomatic people have caused the virus to spread more readily in communities.
Say two similar people are exposed to different quantities of coronavirus particles. Is one of them likely to get sicker from the ensuing COVID-19 disease than the other?
Researchers have found the viral load in infected children to be very high, especially in the first 2 days of infection. We know that transmissibility or risk of contagion is greater with a high viral load.
A new analysis from Scripps Research found 30-40% of people with coronavirus are asymptomatic, but that factor doesn’t mean they are immune from impacts of the disease. Research suggests patients who don’t show any symptoms may still suffer internal organ damage, including lung abnormalities.
Covid-19 can leave the lungs of people who died from the disease completely unrecognisable. Minority groups show higher rates of admission to hospital, which shows they are more likely to have become infected under conditions where the virus dose is maybe high.
In order to get infected you need to get exposed to an infectious dose of the virus; based on infectious dose studies with other coronaviruses, it appears that only small doses may be needed for infection to take hold. Learn where and how your risks increase.
Is the initial dose of SARS-CoV-2 (the virus that causes COVID-19) related to the disease severity? At the moment, we just don't know. The only way to answer this question definitively is with "experimental challenge studies", which involves intentionally infecting healthy volunteers in order to study diseases and their treatments.