In a glimmer of hope in the fight against COVID-19, a new study by Singaporean infectious disease experts has revealed that coronavirus patients are no longer infectious 11 days after contracting the virus even if they still test positive on day 12. In fact, patients may test positive for up to two weeks, with tests being able to detect fragments of the remaining virus in the body, even though it can no longer be spread.
The National Center for Infectious Diseases and the Academy of Medicine examined the “viral load” in 73 COVID-19 patients to determine if the deadly virus was still viable and could infect anyone. The researchers wrote that the virus “could not be isolated or cultured after day 11 of illness.”
“Based on the accumulated data since the start of the COVID-19 pandemic, the infectious period of [coronavirus] in symptomatic individuals may begin around two days before the onset of symptoms, and persists for about 7-10 days after the onset of symptoms,” the researchers wrote. “Active viral replication drops quickly after the first week, and viable virus was not found after the second week of illness.”
In the United States, many hospitals will not declare patients to be fully recovered from COVID-19 until they test negative on two separate occasions or the virus. This latest finding could better assist hospitals in determining when to discharge patients.
NCID executive director Leo Yee-Sin told Singaporean newspaper the Strait Times that while the study was small, the results could lead to studies on a larger scale with identical results.
“Scientifically, I’m very confident that there is enough evidence that the person is no longer infectious after 11 days.”