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From Infection to Recovery: How Long It Lasts
Covid-19’s duration varies widely depending on severity, but now we know the rough range

In the early weeks of the Covid-19 crisis, little was known about the wide range of possible symptoms and the typical progression of the disease. Now, well into the coronavirus outbreaks, doctors and researchers are finally getting a handle on the typical duration of the illness and how it plays out.
It all starts when a person is infected by SARS-CoV-2. The virus, entering most often through the mouth, nose, or eyes, gets into the respiratory system and incubates before announcing itself through symptoms. This incubation is a bit like a chicken egg developing before it hatches.
Covid-19 is known to take anywhere from two to 14 days before it triggers symptoms, with a median of four to five days, according to the U.S. Centers for Disease Control and Prevention. There are known exceptions, up to 19 days. During incubation, a person can be infectious. It’s not yet known how early the period of infectiousness starts, but this period of “viral shedding” is thought to typically begin two to three days before symptoms start, and reach a maximum around day five for mild cases and around day 10 for severe cases, according to one small study on early data, published in the journal Nature.
When the virus does take hold, the onset of symptoms is typically gradual, so a person may not realize they have Covid-19 for up to three weeks after they’ve contracted it.
A person might start out with mild or moderate symptoms. “Then on days 5 to 9 it can really explode in those people who are destined to develop severe disease.”
“For those three weeks, that individual can spread the virus, because they may not be sick, or they may not feel too sick,” says Mark Cameron, PhD, an immunologist and medical researcher in the School of…