This undated handout photo from the Centers for Disease Control and Prevention (CDC) shows a microscopic view of the Coronavirus at the CDC in Atlanta, Georgia. According to the CDC the virus that causes Severe Acute Respiratory Syndrome (SARS) might be a "previously unrecognized virus from the Coronavirus family."
Eight months since a mysterious pneumonia cluster was reported out of China, information and understanding about novel-coronavirus continue to evolve — yet much is still not understood.
On Aug. 14 the Centers for Disease Control once again issued new information. This time, they’ve updated their isolation guidance. They say that research shows that people can test positive for up to three months after being infected with coronavirus, but most people are only contagious for about 10 days of their infections.
According to the CDC, “the duration of infectiousness in most people with COVID-19 is no longer than 10 days after symptoms begin and no longer than 20 days in people with severe illness or those who are severely immunocompromised.”
The CDC Says Retesting Isn’t Necessary in the 3 Months After Diagnosis Unless They Continue to Have Symptoms of COVID-19
GettyA researcher works on a vaccine against the new coronavirus COVID-19 at the Copenhagen’s University research lab in Copenhagen, Denmark, on March 23, 2020.
In the press release issued Friday, the CDC wrote, “The latest data simply suggests that retesting someone in the three months following initial infection is not necessary unless that person is exhibiting the symptoms of COVID-19 and the symptoms cannot be associated with another illness.”
The CDC points out that the findings don’t mean that a person is immune to reinfection during those three months, rather, the virus may show up long after a person is contagious.
As far as isolation goes, which has been recommended to be 14 days from the onset of symptoms or a positive test, now the CDC says that “at least” a 10 day isolation period is sufficient, writing, “people with COVID-19 should be isolated for at least 10 days after symptom onset and until 24 hours after their fever subsides without the use of fever-reducing medications.”
The World Health Organization also said in July researchers are finding is that a positive COVID-19 test doesn’t necessarily mean a person is contagious.
According to the WHO:
Detection of viral RNA does not necessarily mean that a person is infectious and able to transmit the virus to another person. Factors that determine transmission risk include whether a virus is still replication-competent, whether the patient has symptoms, such as a cough, which can spread infectious droplets, and the behavior and environmental factors associated with the infected individual. Usually 5-10 days after infection with SARS-CoV-2, the infected individual starts to gradually produce neutralizing antibodies. Binding of these neutralizing antibodies to the virus is expected to reduce the risk of virus transmission.
Both the CDC & the WHO Say Symptoms are Most Transmittable at the Onset of the Virus Even Though a Person May not be Showing Symptoms.
GettyA staff member checks the temperature of a guest entering the casino of the New Orient Landmark hotel in Macau on January 22, 2020, after the former Portuguese colony reported its first case of the new SARS-like virus that originated from Wuhan in China.
After months of studying coronavirus, researchers seem to be finding that like the common cold, which is the same family of viruses as coronavirus, a person is most contagious in the early stages of having it, because the viral load is strongest then and shedding the most. Over time, the ability for a virus to infect others decreases.
“Researchers have found that the amount of live virus in the nose and throat drops significantly soon after COVID-19 symptoms develop,” the CDC wrote.
This information comes from “more than 15 international and U.S.-based studies recently published looking at length of infection, duration of viral shed, asymptomatic spread and risk of spread among various patient groups,” The CDC reported.
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