Japan's health ministry is preparing to conduct antibody tests later this month to investigate the extent of the spread of the novel coronavirus, it was learned Wednesday. 

The tests are expected to help estimate the total number of infected people and how much the virus has spread, as some 80 pct of carriers of the virus are thought to show only mild or even no symptoms, sources said.

The ministry plans to randomly sample several thousand people for the tests, the sources said. Around 200 million yen is earmarked for the project under the government's draft supplementary budget for the fiscal year that started this month.

Antibodies are proteins created to protect the body from invading viruses. It is possible to check whether someone has been infected with a specific virus in the past by testing their blood for antibodies.

Meanwhile, polymerase chain reaction (PCR) tests are used to check whether someone is infected with a virus at the moment. Concerns have been raised that the full extent of the coronavirus virus spread has not been grasped as the number of PCR test cases is not catching up with the speed of the outbreak.

Antibody tests for the novel coronavirus have been conducted in Los Angeles and other places, with results from one of the tests suggesting that the actual number of infected people was up to 55 times higher than had been reported.

Many countries are seeking to use antibody tests to understand the spread of the virus, in preparation for restarting economic activities.

JIJI Press