How Long After Having Coronavirus Are You Contagious? Here's What Doctors Say
If you've tested positive for COVID-19 or have symptoms of the virus, the advice from the Centers for Disease Control and Prevention (CDC) is clear: Don’t leave your home unless you need medical care, and wear a cloth face covering over your nose and mouth if you must be around others, even at home. But how long should you keep taking these precautions after you’ve recovered from the coronavirus?
Infectious disease expert Amesh A. Adalja, MD, senior scholar at the Johns Hopkins Center for Health Security in Maryland, tells Health that someone who has had COVID-19 stops being contagious approximately 10 days after symptom onset and after at least three days without fever.
This is in line with the CDC‘s recommendation that a person diagnosed with COVID-19 can be released from isolation after 10 days from symptom onset and at least three days from fever resolution and improvement in respiratory symptoms.
“This is supported by the WHO (World Health Organization), and I should add that no secondary spread or transmission has been seen after following this guideline,” epidemiologist Supriya Narasimhan, MD, division chief of infectious diseases and medical director of infection prevention at Santa Clara Valley Medical Center, in California, tells Health.
However, like so many aspects of this virus, scientists are discovering new information all the time, and that can change official advice. For example, Dr. Narasimhan mentions a paper from China that suggests sicker patients may be contagious for up to 21 days—although it should be noted that details of this study aren’t yet fully available.
“I bring this up to show that the information on this virus is constantly evolving and we learn more each day,” explains Dr. Narasimhan. “It is fair to say that sicker people will take longer to recover from their symptoms as well and will need to stay isolated to prevent transmission to others for a longer time period, until they have shown symptom improvement as per the CDC recommendation.”
If you’ve had the coronavirus, it’s wise to check with your doctor and your local public health guidelines to establish when you can be released from isolation. Some places may be more conservative than the CDC—for instance, Santa Clara County Public Health advises remaining in isolation for 14 days from the onset of symptoms and at least seven days from fever resolution and improvement in respiratory symptoms.
When you do go out in public or mix with other people after fully recovering from COVID-19, it’s still important to take preventative measures to help reduce the spread of the virus.
“Follow what the CDC recommends,” says Dr. Narasimhan. “They should maintain a distance of six feet from others when possible, practice meticulous hand hygiene, and cover their nose and mouth with a face covering or mask.”
The face covering is “probably the most important of the three,” Dr. Narasimhan adds, because it provides “source control,” in other words, it prevents infectious particles that may come out of a person’s mouth when they cough, sneeze, or talk from getting into the surrounding airspace.
“It’s important that all of us—including those who have recovered from COVID-19—maintain these safety precautions until we stop the spread of this pandemic,” says Dr. Narasimhan.
The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.