MOSCOW: Antibody tests to detect the proteins produced by the body to fight coronavirus infection are cheap, widely available and actively marketed in Russia.
Yet Western health experts say the tests are unreliable for diagnosing COVID-19 or assessing immunity to it.
When Russians talk about the coronavirus over dinner or in hair salons, the conversation often turns to "antitela," the Russian word for antibodies.
President Vladimir Putin even referred to them while bragging to Turkey's leader about why he avoided infection even though dozens of people around him caught COVID-19.
But the antibodies the popular tests look for can only serve as evidence of a past infection, and scientists say it's still unclear what level of antibodies indicates protection from the virus and for how long. In Russia, it's common to get an antibody test and share the results.
Their use appears to be a factor in the country's low vaccination rate even as the country reports record daily deaths and infections are rising again.
Both the World Health Organization and the U.S. Centers for Disease Control recommend vaccination regardless of previous infection.