Antibody tests may lead to laxness on health protocols, experts warn


Posted at Jul 11 2021 04:48 PM

MANILA — Experts have warned that getting jabbed with coronavirus vaccines might lead people to get lax prematurely on health protocols, and antibody testing after vaccination may worsen this.

A group of doctors specializing in allergy and immunology on Saturday cautioned coronavirus-vaccinated individuals against taking an antibody level test — a tool to check one's level of protection against COVID-19 — because this might create a false sense of protection against the virus, which has now produced several variants that are deemed more infectious and have lowered some vaccines' efficacy.

In a statement, the Philippine Society of Allergy, Asthma and Immunology (PSAAI) said that tests in the Philippines used to measure the amount of protection elicited by COVID-19 vaccines were not yet evaluated and assessed. 

Inaccurately interpreted antibody test results, it said, may give people a false sense of protection which may push them to lower their guard.


Some people even posted their antibody level test results on social media, in a bid to prove that vaccines work. But the science is not that simple, the group said. The PSAAI said that the level of antibodies that will give sufficient immunity against a coronavirus infection has yet to be determined.

"Antibody tests can be qualitative or quantitative. Neither a 'positive' qualitative nor a 'high' quantitative test result can tell if a person is adequately protected or not after COVID-19 vaccination," said the PSAAI. 

"More research is needed to understand the meaning of a positive or a negative test beyond the presence or absence of antibodies."

Also, the group said that if the test used was not designed to detect the antibodies produced by a certain COVID-19 vaccine, "then the post-vaccination serologic test will most likely be negative."

Based on current data, it added that standardized tests that can measure neutralizing antibodies — which prevent SARS-CoV-2, the virus that causes COVID-19, from infecting a cell — are still under investigation.

"Antibodies to COVID-19 may include binding and neutralizing antibodies. . . . The role of binding antibodies after COVID-19 infection is not yet clear. Many COVID-19 antibody tests are non-specific and can test both binding and neutralizing antibodies. There are some neutralizing antibody tests (quantitative and qualitative) available but the gold standard test for this has not yet been established."

The group noted that their statement would be updated once new information becomes available. 

Check out the simplified, and translated in Filipino, version of the PSAAI statement by Dr. Carlo Trinidad on Twitter: