Published 14:23 IST, May 27th 2020
COVID-19: US CDC says antibody tests might be wrong half the time
Antibody tests used to determine if people have contracted COVID-19 infection might be wrong up to half time, US Centre for Disease Control and Prevention said.
Antibody tests used to determine if people have contracted the COVID-19 infection might be wrong up to half the time, US Centre for Disease Control and Prevention (CDC) wrote on its website. The antibody tests or serologic tests look for evidence of an immune response to infection. However, according to the CDC, these tests are not accurate enough to base new policies on them.
'Should not be used to group people'
"Serologic test results should not be used to make decisions about grouping persons residing in or being admitted to congregate settings, such as schools, dormitories, or correctional facilities. It should also not be used to make decisions about returning persons to the workplace," the CDC wrote in new guidelines published on its website.
In addition to that, the US body also recommended health officials to use “most accurate tests they can find” and to test people twice before declaring any results. "In most of the country, the prevalence of SARS-CoV-2 antibody is expected to be low, ranging from less than 5% to 25%, so that testing at this point might result in relatively more false-positive results and fewer false-negative results", it added.
CDC also said that across populations, these tests gave more accurate results if the disease was common for the population. It further explained that if an infection has only affected a small percentage of people being tested, even a very small margin of error in a test will be magnified. This comes as many health experts have continuously been warning the US government of inaccurate test results.
Meanwhile, the US continues to top the countries with the most number of coronavirus cases. As per John Hopkins University, a total of 1,68,1418 people have been tested positive while 98,298 people have died. The state of New York still remains the worst whit with 29,302 deaths.
Updated 14:23 IST, May 27th 2020