Nature Medicine Published a new study, that the coronavirus antibodies may last only 2 to 3 months, especially in people who never show clinical symptoms while they get infected with coronavirus.
The researchers investigated 37 asymptomatic individuals in the district of Wanzhou that’s southwest of China – those who were diagnosed with RT-PCR-confirmed SARS-CoV-2 infections but never developed any relevant clinical symptoms of the virus that causes COVID-19 disease. Their antibody response was compared to that of the 37 who showed symptoms, and researchers found that people without symptoms had a weaker antibody response than those with symptoms.
Within 8 weeks 81% of the asymptomatic people had a decrease of the naturalizing antibodies, that compared to the 63% of symptomatic patients. The study also showed that antibodies decreased to an undetectable levels in 40% of asymptomatic people, compared to the 12.9% of symptomatic people.
Several experts suggested that the new findings do not necessarily mean that these people can be infected a second time, given that even low levels of powerful neutralizing antibodies may still be protective, as are the immune system’s T cells and B cells.
However, the results give a strong note of caution against the idea of “immunity passports,” which have been issued by some countries to enable people who have recovered from COVID-19, to travel or return to work.
Scientists from across the globe say they are still learning about key aspects of the coronavirus, including how immune systems respond once a person is exposed. But there is not enough evidence to indicate that the coronavirus antibodies ensure immunity against the virus and how long immunity lasts if antibodies do provide protection.