Does the 24-hour cycle affect how well PCR tests for SARS-CoV-2 work?
In the current global pandemic crisis, it is very important that the virus that causes COVID-19 be found and stopped as soon as possible. Polymerase chain reaction (PCR) tests are often used in hospitals and clinics because they are very accurate. However, up to 30% of false-negative tests happen, especially in the early stages of an infection. Some patients say that their symptoms, like fever and body aches, are worse in the late afternoon. This made us wonder if viral shedding might also be different at different times of the day. If this is true, it could affect the accuracy of PCR test and rapid test at different times of the day, which would have important implications for testing strategies and ways to stop the spread of viruses. To find out if SARS-CoV-2 viral shedding might change depending on the time of day, we looked at the results of more than 86,000 PCR tests for SARS-CoV-2 taken from more than 68,000 patients in a healthcare system in the south eastern U.S. from...