How long are you going to test positive for COVID after taking a test? Two experts weigh in, and advise on testing and isolation guidelines to follow.

How long does flu show up on PCR? There is some variation in how long PCR tests take to detect flu. It all depends on the specifics of the sample and the test.

A negative result from a COVID test in a medical setting is more accurate than a negative result from an at-home test, ...

In general, rapid antigen tests are less sensitive and therefore less likely to detect an infection compared with polymerase chain reaction (PCR) tests. PCR tests look for viral genetic material, ...

There are three different ways to test for COVID-19: PCR tests, antigen tests and antibody tests. Here are the differences.

By providing quantitative information about Covid-19 infection, PCR testing can help guide isolation and return to school or work policies.

Only a single PCR test is required by comparison. If you need testing more quickly, there are other programs offering free or low-cost tests, including community-based testing sites.

A new COVID variant is spreading. Here's what you need to know about the incubation period, symptoms and when to take a test.

But lab-based PCR tests amplify the genetic material in a different way to this home-based test. So, strictly speaking, this new test is not a PCR test. The new test isn’t a RAT either.