How long is a person infected with COVID-19 contagious?
How long is a person infected with COVID-19 contagious?
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Recent research has shown that a person infected with COVID-19 may be able to spread the virus up to 72 hours before they begin to have any symptoms and up to 10 days after symptoms disappear. New studies have suggested that people are the most infectious in the 48 hours before they start to experience any symptoms. People who test positive for COVID-19 but do not develop symptoms in the 10 days following the test result are considered to be likely no longer contagious after those 10 days. There may be exceptions to these timings, so experts recommend 10 days of isolation after either testing positive for the virus, being exposed to a person who has been infected with COVID-19, or developing any symptoms. The best way to ensure you are no long contagious is by having two negative COVID-19 tests more than 24 hours apart. However, as per the U.S. CDC, individuals who were severely ill from COVID-19 or are severely immunocompromised might need to remain isolated for longer than 10 days and up to 20 days because they may still be producing viral particles.
Recent research has shown that a person infected with COVID-19 may be able to spread the virus up to 72 hours before they begin to have any symptoms and up to 10 days after symptoms disappear. New studies have suggested that people are the most infectious in the 48 hours before they start to experience any symptoms. People who test positive for COVID-19 but do not develop symptoms in the 10 days following the test result are considered to be likely no longer contagious after those 10 days. There may be exceptions to these timings, so experts recommend 10 days of isolation after either testing positive for the virus, being exposed to a person who has been infected with COVID-19, or developing any symptoms. The best way to ensure you are no long contagious is by having two negative COVID-19 tests more than 24 hours apart. However, as per the U.S. CDC, individuals who were severely ill from COVID-19 or are severely immunocompromised might need to remain isolated for longer than 10 days and up to 20 days because they may still be producing viral particles.
Publication
What our experts say
Recent research has shown that a person infected with COVID-19 may be able to spread the virus up to 72 hours before they begin to have any symptoms and up to 10 days after symptoms disappear. New studies have suggested that people are the most infectious in the 48 hours before they start to experience any symptoms.
People who test positive for COVID-19 but do not develop symptoms in the 10 days following the test result are considered to be likely no longer contagious after those 10 days.
There may be exceptions to these timings, so experts recommend 10 days of isolation after either testing positive for the virus, being exposed to a person who has been infected with COVID-19, or developing any symptoms. The best way to ensure you are no long contagious is by having two negative COVID-19 tests more than 24 hours apart.
However, as per the U.S. CDC, individuals who were severely ill from COVID-19 or are severely immunocompromised might need to remain isolated for longer than 10 days and up to 20 days because they may still be producing viral particles.
Recent research has shown that a person infected with COVID-19 may be able to spread the virus up to 72 hours before they begin to have any symptoms and up to 10 days after symptoms disappear. New studies have suggested that people are the most infectious in the 48 hours before they start to experience any symptoms.
People who test positive for COVID-19 but do not develop symptoms in the 10 days following the test result are considered to be likely no longer contagious after those 10 days.
There may be exceptions to these timings, so experts recommend 10 days of isolation after either testing positive for the virus, being exposed to a person who has been infected with COVID-19, or developing any symptoms. The best way to ensure you are no long contagious is by having two negative COVID-19 tests more than 24 hours apart.
However, as per the U.S. CDC, individuals who were severely ill from COVID-19 or are severely immunocompromised might need to remain isolated for longer than 10 days and up to 20 days because they may still be producing viral particles.
Context and background
Some viruses are capable of replicating themselves, shedding and spreading even after symptoms have stopped. Scientists are still studying the new coronavirus. Evidence we have so far has given us a solid idea of this length of time for the vast majority of patients. There are still some outliers, but most patients fall within the time frames of contagiousness. Severe cases of illness from COVID-19 and immunocompromised persons would need individual advise from infectious disease experts because they are capable of being contagious longer than others.
Some viruses are capable of replicating themselves, shedding and spreading even after symptoms have stopped. Scientists are still studying the new coronavirus. Evidence we have so far has given us a solid idea of this length of time for the vast majority of patients. There are still some outliers, but most patients fall within the time frames of contagiousness. Severe cases of illness from COVID-19 and immunocompromised persons would need individual advise from infectious disease experts because they are capable of being contagious longer than others.
Resources
- When you can be around others (U.S. CDC)
- Harvard Medical School questions about COVID-19 exposure (Harvard Health)
- Duration of Isolation & Precautions for Adults (U.S. CDC)
- Clinical Questions about COVID-19: Questions and Answers (U.S. CDC)
- When you can be around others (U.S. CDC)
- Harvard Medical School questions about COVID-19 exposure (Harvard Health)
- Duration of Isolation & Precautions for Adults (U.S. CDC)
- Clinical Questions about COVID-19: Questions and Answers (U.S. CDC)
