The US Centers for Disease Control and Prevention (CDC) said Monday it is shortening the recommended time for isolation from 10 days for people with COVID-19 to 5 days, if asymptomatic, followed by 5 days of wearing a mask when around others.
The CDC said the update is being made given what “currently know about COVID-19 and the Omicron variant.”
According to the CDC, the change is motivated by science demonstrating that the majority of SARS-CoV-2 transmission occurs early in the course of illness, generally in the 1-2 days prior to onset of symptoms and the 2-3 days after. Therefore, people who test positive should isolate for 5 days and, if asymptomatic at that time, they may leave isolation if they can continue to mask for 5 days to minimize the risk of infecting others, the CDC said.
Additionally, the CDC said it is updating the recommended quarantine period for those exposed to COVID-19. For people who are unvaccinated or are more than six months out from their second mRNA dose (or more than 2 months after the J&J vaccine) and not yet boosted, CDC said it now recommends quarantine for 5 days followed by strict mask use for an additional 5 days.
“Alternatively, if a 5-day quarantine is not feasible, it is imperative that an exposed person wear a well-fitting mask at all times when around others for 10 days after exposure,” the CDC said, adding that individuals who have received their booster shot do not need to quarantine following an exposure, but should wear a mask for 10 days after the exposure.
“For all those exposed, best practice would also include a test for SARS-CoV-2 at day 5 after exposure. If symptoms occur, individuals should immediately quarantine until a negative test confirms symptoms are not attributable to COVID-19,” the CDC said.
According to the CDC, data from South Africa and the United Kingdom demonstrate that vaccine effectiveness against infection for two doses of an mRNA vaccine is approximately 35%. A COVID-19 vaccine booster dose restores vaccine effectiveness against infection to 75%. COVID-19 vaccination decreases the risk of severe disease, hospitalization, and death from COVID-19. CDC strongly encourages COVID-19 vaccination for everyone 5 and older and boosters for everyone 16 and older.