STATEN ISLAND, NY — As the omicron variant continues to sweep through New York City, the Big Apple is enduring a average coronavirus (COVID-19) positivity rate by nearly 33% in the last 28 days, getting accurate test results is more important than ever.
However, waiting until dark to get tested for coronavirus could make your results less accurate. according to a new study from Vanderbilt University.
“Taking a COVID-19 test at the optimal time of day improves the sensitivity of the test and will help us be accurate in diagnosing people who may be infected but asymptomatic,” said Carl Johnson, professor of biological sciences at Vanderbilt.
But why does getting tested at different times of the day impact the accuracy of test results?
The researchers found that the virus acts differently in our bodies depending on our circadian rhythm, with viral shedding, the process by which infected cells release virus particles, being most active in the middle of the day.
The study indicates that people who test in the middle of the day are up to twice as likely to have an accurate positive result as those who test at night.
The results showed that patients’ viral loads are lower after 8 p.m., meaning those tested late at night are at higher risk of receiving a false negative result.
False negative results can be of particular concern, as they can cause an infected person to unknowingly spread the virus to other members of the community.