LATEST: How Long Are You Infectious With COVID?

September 1, 2022
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Individuals with COVID-19 are required to undergo at least five days of isolation, regardless of vaccination status. CDC defines isolation as a precaution to separate yourself when you either have COVID-19 or manifest any of its symptoms.  

However, new studies now show that the MAJORITY of people can be infectious with COVID-19 for days longer than many believe. 

So just how long can you still pose a risk to others?  

How long should you isolate when testing positive for COVID-19?

BODY IMAGE 2 How long are you infectious with covid min

New York State guidelines still say that you should isolate yourself for five days. The first appearance of symptoms or the day you got tested should be treated as ‘Day 0’. 

However, if you’ve only come into close contact with someone who has COVID-19, you are no longer required to quarantine if:

  • You tested positive for COVID-19 using a molecular test within the last 90 days and have subsequently tested negative
  • You’re over five years old and have received all recommended COVID-19 vaccine shots  

The state suggests ending isolation after 5 days only when the following occur:

  • You are fever-free for the last 24 hours WITHOUT using any fever-reducing medication
  • Other symptoms have improved (excluding loss of taste and smell which can continue for weeks or even months)
  • You never had any symptoms (a COVID-19 asymptomatic infection) and have tested negative after 5 days.

* If you need to go out after your five day isolation, continue wearing a mask around others for five more days. 

Furthermore, CDC advises individuals who experienced a severe illness or shortness of breath to:

  • Isolate for at least ten days or depending on the recommendation of your doctor
  • If symptoms recur, restart isolation at day zero. 
  • Avoid being around immunocompromised people until at least day 11

No, 5 days is not the longest you can be infectious with COVID

A common misconception people have is that they are automatically free to end isolation five days after the onset of symptoms. The reality is, they can still transmit the disease, making it essential to take a final test just to be sure. 

In fact, a study by Imperial College London released in the last week reveals new details about how long infectiousness with COVID is possible.

“There is a lack of clarity around how to come out of self-isolation safely,” said  Dr. Seran Hakki, one of the co-authors of the study.  “If you test positive for COVID-19 or have symptoms after being in contact with someone with confirmed COVID-19, you should try to stay at home and minimize contact with other people.”

New study reveals how long someone is infectious with COVID

The study, which is published on The Lancet’s Respiratory Medicine website, conducted a study of 57 people with COVID-19. Based on their findings, the researchers recommend that people with COVID-19 isolate for five days after symptoms begin. But before ending isolation, they should complete lateral flow tests on the sixth day. 

Here’s a summary of some of the findings of the study:

  • TWO-THIRDS of COVID-19 patients are STILL infectious five days after the onset of symptoms 
  • Almost a QUARTER of patients were infectious seven days after the onset of symptoms
  • A negative lateral flow COVID test is the best way to determine if someone is no longer infectious with COVID-19
  • Only one in five participants of the study were infectious before having COVID-19 symptoms
  • The AVERAGE duration of infectiousness of someone with COVID-19 was five days
  • People with COVID-19 were most infectious on the third day

“By using special daily tests to measure how infectious the virus is (not just PCR tests) and daily symptom records, we were able to define the window in which people are infectious,” said Ajit Lalvani, director of the NIHR Respiratory Infections Health Protection Research Unit at Imperial and co-author of the study.

He added: 

“Combining our results with information about Omicron infections, the duration of infectiousness we’ve observed can be generalized to current variants. Our evidence can be used to inform infection control policies and self-isolation guidance to help reduce the transmission of COVID-19.”

Importance of using lateral flow tests

Despite not showing any symptoms of COVID-19 five days after testing positive, it’s vital to get tested before ending isolation. Lateral flow tests are highly accurate in identifying whether someone is still infectious with COVID-19… if done correctly.

The study found that the sensitivity of these tests was poor at identifying the start of a COVID-19 infection. But, it is very reliable in identifying peak levels of infectiousness. Sensitivity levels of lateral flow tests go from 67% at the start of infection to 92% during peak levels of infection. 

The researchers suggest getting TWO negative tests before ending isolation. 

“We recommend that anyone who has been exposed to the virus and has symptoms isolates for five days. After the five days, conduct daily lateral flow tests to safely leave isolation when two consecutive daily tests are negative,” said Lalvani. 

However, if a person continues to test positive or does not have access to lateral flow devices, they should stay in isolation. And to minimize transmission, they should only end isolation on the 10th day after they experienced any symptoms. 

Final thoughts

If you manifest any symptoms of COVID-19 or come in close contact with someone who has COVID-19, get tested immediately. And while waiting for the results of your test, isolate yourself from others.

As of this writing, the US still reports over 92,000 COVID-19 cases daily.

Even if you’ve finished your five day isolation, it’s vital to get tested before going back out into the real world. 

This includes going to work, attending public gatherings (indoor and outdoor), and visiting anyone who is immunocompromised. Studies have proven that lateral flow tests are still the best way to determine whether you’re infectious with COVID-19.

What’s more, there are myriad options available for you to get tested for the virus. For starters, you can have a COVID-19 testing kit delivered straight to your home

If you reside in the NYC area, you have two more options. You can either schedule an in-person lab test or have one delivered via Uber

The advantage with these test options is that it’s far less likely there will be errors in testing. All test results will be analyzed in a laboratory by medical professionals. 

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