The World Health Organization has backed off on the idea that individuals can only catch the coronavirus once, as well as proposals to reopen a society based on this immunity.
In a scientific brief on Friday, the United Nations agency said that the idea that an infection could lead to immunity for a time was unconfirmed and therefore unreliable as the foundation for the next phase of the global response to the pandemic.
“Some governments have suggested that the detection of antibodies to the SARS-CoV-2, a virus that causes COVID-19, may serve as a basis for an ‘immunity passport’ or ‘risk-free certificate’ that allows individuals to travel. WHO wrote. “There is currently no evidence that individuals recovering from COVID-19 and having antibodies are protected from a second infection.”
A few days after Chile announced it would begin issuing immunity cards that would be effective as passports, it would allow passengers to clear security at airports, with a document showing they had recovered from the virus.
Authorities and researchers in other countries, such as France and the United Kingdom, have expressed interest in such ideas, but US lawmakers such as Los Angeles Mayor Eric Garcetti. Some officials in the organization have called it a reopening strategy.
The concept of such a card is that a person can only hesitate once before developing the antibodies needed to fight the coronavirus. That premise falls into another general theory: the so-called herd immunity, if enough people are infected with coronavirus – and therefore immune – slows its transmission and reduces the risk of infection even for those who do not.
But these ideas are heavily dependent on the fact that the coronavirus is not caught for a second – something that global health officials have said is something that leaders should not be counting on now. As of Friday, WHO said, “No study has evaluated whether the presence of antibodies to SARS-CoV-2 provides immunity to this virus in humans.”
What’s more, reports from the world’s earliest COVID-19 hotspots, such as South Korea and China, show that the disease is relapsing as the number of recovered patients increases.
By mid-April, Korean health officials said that only 2% of the country’s recovering patients were again alone after testing positive for a second time. In Wuhan, China, data from several quarantine facilities in the city, and patients for observation after discharge from hospitals show that 5% to 10% of patients who have “recovered” have positive tests again.
It is unclear why this occurs – it is a sign of a second infection, a reactivation of the remaining virus in the body, or the result of an inaccurate antibody test.
Dozens of antibody tests for the coronavirus novel are already on the market, including reliability and accuracy. House Democrats have begun investigating antibody tests and whether the Food and Drug Administration should increase their enforcement, CNN said.
“At this time in the pandemic, there was insufficient evidence to support the effectiveness of antibody-mediated immunity to guarantee the accuracy of an ‘immunity passport’ or ‘risk-free certificate’,” the WHO warned.
“People who think they are immune to a second infection may ignore public health advice because they have received a positive test result. The use of such certifications increases the risk of persistent transmission.”