The CDC clarified that a recent update to its quarantine guidance does not imply that people are immune to reinfection from the new coronavirus within three months of their first infection.
The agency updated its guidance on who needs to quarantine Aug. 3, stating that people who have been in close contact with someone who has COVID-19 need to quarantine, excluding people who have had COVID-19 within the last three months.
"People who have tested positive for COVID-19 do not need to quarantine or get tested again for up to three months, as long as they do not develop symptoms again," the updated recommendations say. "People who develop symptoms again within three months of their first bout of COVID-19 may need to be tested again if there is no other cause identified for their symptoms."
This update appeared to indicate that immunity to the new coronavirus may last for three months after recovery from the disease. But the CDC issued a statement Aug. 14 saying that was not the case.
"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 statement says.
The agency also added a note to its quarantine guidance saying that data shows recovered COVID-19 patients may have low levels of virus in their bodies for up to three months after diagnosis. Thus, if the person who has recovered from COVID-19 is retested within three months of the first infection, "they may continue to have a positive test result, even though they are not spreading COVID-19."
Editor's note: This article was updated Aug. 17 at 10:51 a.m. CT to include information from the CDC's clarification statement.