Antibodies against other coronaviruses present in the human body may serve as a new defense against SARS-CoV-2 for the body. This is evidenced by a new study by Spanish scientists published in the journal Nature Communications.
Seven of the vast family of coronaviruses infect humans. Most of them only cause colds. There are three exceptions: MERS-CoV, SARS-CoV and SARS-CoV-2.
A team of specialists led by researchers from the Barcelona Institute of Global Health for seven months – from March to October 2020 – studied the level of antibodies in the blood of 578 employees of the Clinical Hospital of Barcelona. They measured the level and type of antibodies to six different SARS-CoV-2 antigens, as well as the presence of antibodies to four more coronaviruses – those that cause SARS in humans.
Researchers have found that most of those who have contracted the coronavirus became infected at the beginning of the pandemic. The percentage of participants with antibodies to SARS-CoV-2 increased slightly – from 13.5 to 16.4 percent, while the number of antibodies itself remained constant or even increased.
In addition, the work of Spanish scientists supports the theory that antibodies against the SARS-causing coronaviruses may provide cross-immunity against COVID-19. Patients who underwent mild COVID-19 had higher IgG and IgA antibody titers to other coronaviruses than those who developed symptoms. Among those who did not become infected with SARS-CoV-2, there was also a trend towards higher levels of such antibodies.
