The head of the World Health Organization has suggested that for now finding new coronavirus cases and treating patients should be prioritized over conducting antibody tests.
WHO Director-General Tedros Adhanom Ghebreyesus spoke to reporters in Geneva on Monday.
He said, "While antibody tests are important for knowing who has been infected, tests that find the virus are a core tool for active case finding, diagnosis, isolation and treatment."
His remarks came as European countries are divided on whether to carry out antibody tests.
Netherlands is working to figure out what percentage of its population may have already developed antibodies against the coronavirus.
The Dutch National Institute for Public Health and the Environment last month announced the launch of an antibody study targeting about 6,000 people.
It said researchers will compare their blood samples with those collected from the same people three years ago.
It added the study, which will last over a year, could shed light on how long the antibodies are effective.
Earlier this month, a blood bank in the Netherlands conducted antibody tests on about 7,000 people aged 18 and above.
Officials completed analysis of about 60 percent of those tested and found that about three percent of them have had antibodies against the virus.
The government of the United Kingdom is also planning to carry out antibody tests. Experts are studying antibody testing kits that people can use at home. But they said they are still unsure about the reliability of those kits and that it would take more time to start antibody testing in the country.
The French government is cautious about carrying out such tests. It says there are many unknowns concerning the testing, including whether people with antibodies are really immune to re-infection.