When someone tests positive for COVID-19various questions arise, such as how long he will have to remain in isolation, as well as when he can continue his daily activities without the risk of transmitting the virus to others.

According to the Washington Post, this is a tricky question.

According to experts, the most important thing to remember is that each person and each case of Covid has its own unique characteristics. There is no universal rule as to how severely ill someone will become or how long they will be at risk of infecting others.

Thus, patients must consider the circumstances in order to prioritize and assess risk.

How long should isolation last?

Coronavirus has the dangerous property of being contagious even before symptoms appear. Typically, the period when a person can transmit the virus starts about a day or two before the onset of symptoms and lasts two or three days after they appear.

Although it is less likely that a person will transmit the virus later in the illness phase, this possibility cannot be ruled out. Studies show that people are still transmitting the virus, which can be cultured in the lab for an average of about eight days after a positive test result.

Experts say the chance of someone transmitting the virus in 10 days is very small, even if tests are still positive.

In addition, many experts believe that self-testing, also known as antigen tests, should be used to get an idea of ​​when someone might be out of isolation.

“Given that a large number of people are still testing positive after five days of rapid tests, perhaps updated guidance [των ειδικών] it should be specified that someone must have a negative rapid test before being released from isolation,” says Tom Inglesby, head of the Johns Hopkins Center for Health Security, who was also a senior adviser to the Biden administration on the tests. from December to April.

“A negative antigen test is a pretty reassuring sign that you can no longer infect other people,” says Amy Barczak, an infectious disease specialist at Massachusetts General Hospital.

“Do I have to take the rapid test again if I get a negative result?”

Barczak says that healthy people who test negative for an antigen on day five or later are “unlikely to transmit the virus to other people.”

For the person who has more reason to be concerned about this particular issue, another test would be a good idea. Experts sometimes recommend that symptomatic patients have a second rapid test to be sure.

Michael Mina, a former Harvard infectious disease epidemiologist and immunologist who specializes in rapid tests, says two tests 24 hours apart can be an extra layer of security, like a double lock on a door.

“Two tests in a row are better protection than one negative test,” he notes.

When is a PCR test recommended?

A PCR test is a type of molecular control that looks for the genetic material of a virus. He can detect it even in the smallest quantities. It’s mostly useful as a confirmatory test to see if we have Covid, but it doesn’t help to know if we can infect others, says Albert Koh, an epidemiologist and infectious disease specialist at Yale University.

It makes no sense to do a PCR test after an illness, because “for the average healthy person, PCR will show a positive result longer than we are actually contagious,” Barczak says.

Rapid antigen tests are more practical than PCR to quickly find out if we can transmit the virus. If someone has symptoms, an antigen test will be more reliable, as the viral load in the body is much higher and therefore easier to detect.

But even without symptoms, someone can get a positive rapid antigen test result and infect others. Most of the tests we do at home give results within 10-15 minutes using nasal samples.

Since the rapid tests provide fast results, they are, in essence, a test for contagiousness. People should use them – even if they are feeling well and have no symptoms – before arranging to attend an indoor event, especially if they are going to be around people who are particularly vulnerable to Covid.

^{Source: Washington Post.}