KOCHI: Several people have been approaching private hospitals and labs for testing their antibody levels to check the efficacy or response of the Covid vaccination. Antibodies induced by vaccination and generated through natural infection can be detected by conducting different types of antibody tests.
Though not recommended by doctors, the possible apprehensions regarding multisystem inflammatory syndrome in adults (MISA) among those who have recovered from Covid infection are likely to have triggered this, experts say.
According to doctors, mainly three types of tests are conducted to know the Covid antibody level. One is the anti-spike antibody test, which is designed to detect the presence and amount of Covid antibodies generated post vaccination. The second is anti-nucleocapsid tests to detect the antibodies generated through natural Covid infection. The third is total antibody profiling that looks at all antibodies together.
For mostly research purposes, neutralising antibody tests are done to check the ability of these antibodies to prevent diseases. According to experts, the accurate correlates of antibody level with protection against infection are yet to be described.
“Normally, antibodies get generated 10-14 days after vaccination. There is no standard cut-off antibody level as of now. Researches and studies are still going on in this regard. The antibody level varies with person to person. Though it is said that antibodies should be over 100 IU (international unit)/ml, it is not well defined. We doctors do not recommend anyone to go for the tests,” said Dr Monu Varghese, pulmonologist based in Kochi.
Almost all private hospitals and labs have the facility to conduct the antibody tests. A major private lab in Kochi conducted more than 20 antibody tests in August. “Rather than the effectiveness of the vaccination, it is the response to the vaccination that is known through the antibody tests. In some cases, Covid antibody level can also be shown zero, as they will not respond to the vaccination. But such situations are rare. Also, antibody testing is quite common in cases of other viral infections including Hepatitis and HIV,” said Dr Omana P, professor of general medicine based in Thrissur.
“Rather than the general public it is the healthcare workers who monitor their antibody level as they are dealing with Covid cases on a regular basis. Since they were in the first lot to get the infection and took the jabs and still had apprehensions of the effectiveness of the vaccines, many of them track their antibody levels,” said Dr Omana.