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Here's How Long You May Be Infectious With COVID-19, Says Study

A positive COVID-19 test doesn't necessarily translate to an active coronavirus infection, research says.
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When it comes to COVID-19, you're probably wondering how long an infection lasts and the time period in which an infected individual is contagious. New research hopes to partially answer one of these questions. According to a new joint research paper by Singapore's National Centre for Infectious Diseases and the Academy of Medicine, coronavirus patients stop being infectious 11 days after they contract the virus—even if they are still testing positive. (However, no matter their finding, you should of course follow the CDC's guidelines on self-isolation and quarantine, available here.)

Examining the "viral load" in 73 coronavirus patients, the research team found that a positive test "does not equate to infectiousness or viable virus. The virus "could not be isolated or cultured after day 11 of illness," they explained. 

"Based on the accumulated data since the start of the COVID-19 pandemic, the infectious period of [coronavirus] in symptomatic individuals may begin around 2 days before the onset of symptoms, and persists for about 7-10 days after the onset of symptoms," they wrote.

A Positive Result May Be Picking Up Just "Morsels"

While patients may still test positive after they are infectious, the researchers explained that tests may just be picking up morsels of the virus that can no longer spread infection. "Active viral replication drops quickly after the first week, and viable virus was not found after the second week of illness," they explained.

According to the US Centers for Disease Control and Prevention, if you are infected with COVID-19 you should remain quarantined from others until three criteria have been met: 3 days with no fever, symptoms have improved, and 10 days have passed since symptoms first appeared. "Depending on your healthcare provider's advice and availability of testing, you might get tested to see if you still have COVID-19. If you will be tested, you can be around others when you have no fever, symptoms have improved, and you receive two negative test results in a row, at least 24 hours apart," they add. 

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However, Don't Break Quarantine Early

The significance of these latest findings has to do with critical healthcare decisions having to do with hospital discharge, or "de-isolation strategies," researchers explain. Instead of focusing on when an individual tests negative for the virus, researchers encourage "revised discharge criteria based on the data on the time course of infectiousness," focusing resources instead on "testing persons with acute respiratory symptoms and suspected COVID-19 in early presentation."

However, if you aren't sure whether you are still infected with COVID-19, you should definitely contact your healthcare provider instead of breaking quarantine a day or two early, and, again, check the CDC's advice here about how long to quarantine. Due to the highly infectious nature of the virus, it could save someone's life.

And to get through this pandemic at your healthiest, don't miss these Things You Should Never Do During the Coronavirus Pandemic.

Eat This, Not That! is constantly monitoring the latest food news as it relates to COVID-19 in order to keep you healthy, safe, and informed (and answer your most urgent questions). Here are the precautions you should be taking at the grocery store, the foods you should have on hand, the meal delivery services and restaurant chains offering takeout you need to know about, and ways you can help support those in need. We will continue to update these as new information develops. Click here for all of our COVID-19 coverage, and sign up for our newsletter to stay up-to-date.

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