The sun is only just rising in Berlin, but 65-year-old Lothar Kopp is already queuing for a clinic in the Reinickendorf district.
Along with a handful of mask-clad people two feet apart, he’s here to give a blood sample – for antibody tests hoping to find out if he has contracted the coronavirus before and has developed immunity ever since.
“If I’ve already had corona, I’m not contagious,” said Kopp, hoping to test positive for antibodies, because it would allow him to visit his elderly mother without risking the disease.
As countries around the world try to curb public life, some experts have suggested the possibility of so-called “immunity passports” to get those with antibodies back to work first.
Tens of thousands of tests have been carried out in Germany and major investigations are ongoing.
Elsewhere in the world, efforts are also being made to determine the so-called immunity level in the population.
New York Governor Andrew Cuomo said last week that the state will launch tests “in the most aggressive manner in the country” to find out how many have already had the disease.
In a hurry to catch up with the tests, the US regulator had even made the extraordinary decision to allow commercial manufacturers to market their tests without formal consent.
But experts, including from the World Health Organization, have urged caution about the accuracy of the budding tests.
One of the unknown factors of the virus is how long immunity could last – meaning that even positive antibody tests may not make sense for long.
On a reminder, a WHO spokeswoman noted that there is “a lot of discussion” about the antibody tests.
But “once we have validated tests, we may still not know how well a positive result correlates with disease protection or how long the protection will last,” she told AFP.
Matthias Orth, board member of the Professional Association of German Laboratory Physicians (BDL), said inaccuracies are a major problem.
People can test negative even if they have had COVID-19, he said.
“There are also quite banal coronaviruses that do not cause serious illness and that can produce a positive result.”
As for the so-called rapid antibody tests – home kits that draw blood from your finger and promise a result in 15 minutes – Orth’s verdict: “They’re bullshit.”
More accurate tests will come after a few weeks, he said, but he emphasized that “it is a little too early to give patients a clear statement that they are absolutely immune.”
Experts also note that while large-scale studies underway in Europe’s largest economy may serve to determine which portion of the population is infected, they cannot say with certainty how many people are actually immune, given the limitations of current antibody testing.
Nonetheless, the studies are closely monitored, including one that started over the weekend in Munich with scientists randomly selecting 3,000 households to test for antibodies.
A separate investigation is underway in Gangelt, in the Heinsberg district, where Germany’s first major cluster of infections was discovered. So far, researchers have determined that 14 percent of the population was previously infected.
In addition to studies, several pharmaceutical companies in Germany have also started to market such antibody tests – to be analyzed in a laboratory.
And so far, about 70,000 tests have been processed by 54 laboratories, according to the ALM Association of Accredited Medical Laboratories.
Dr. Ulrike Leimer-Lipke from the Reinickendorf clinic, who has been offering antibody tests since mid-March, said, “I think it makes a lot of sense because this way we can check whether people have immunity.
“It is very important for people to have a grandmother or a mother or father they care for to know if they are already immune.”
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