DENVER (KDVR) — Studies of COVID-19 are in the early stages, and while many researchers say there are still unknowns, experts have learned a lot about the virus since March.
When it comes to isolation and quarantine, why does the Centers for Disease Control recommend 14 days?
According to studies from the CDC, the coronavirus can continue to shed from a recovered person for up to 3 months after illness onset.
WebMD defines viral shedding as,
“Viral shedding occurs when a virus replicates inside your body and is released into the environment. At that point, it may be contagious. For the coronavirus that causes COVID-19, it’s not known exactly when this occurs after someone is infected. Evidence suggests that the novel coronavirus is most contagious when symptoms are worse and viral shedding is high. However, it appears that someone is contagious prior to developing symptoms, suggesting that viral shedding is occurring even early in the infection.”
The CDC says the available data from the studies indicates that someone with mild to moderate COVID-19 symptoms will no longer be infectious 10 days after the onset of symptoms.
A person with with more severe to critical illness or a person severely immunocompromised will likely remain infectious no longer than 20 days after symptom onset, according to the CDC.
Once recovered, the CDC says a person can continue to shed detectable COVID-19 RNA in upper respiratory specimens for up to 3 months after the onset of the illness, even though the concentrations of COVID-19 are much lower than when the person is actually sick.
When it comes to someone who never develops symptoms, the CDC says isolation and other precautions can be discontinued 10 days after their first positive COVID-19 PCR test.