Coronavirus antibodies can last at least three months after a person becomes infected with the virus that causes COVID-19, according to a study published in Science Immunology.
Researchers from the University of Toronto and the Lunenfeld-Tanenbaum Research Institute at Sinai Health used both saliva and blood samples from COVID-19 patients to measure and compare antibody levels for over three months post-symptom onset.
They found that antibodies of the IgG class that bind to the SARS-CoV-2 spike protein are detectable for at least 115 days, representing the longest time interval measured. The study is also the first to show these antibodies can also be detected in the saliva.
“Our study shows that IgG antibodies against the spike protein of the virus are relatively durable in both blood and saliva,” said Jennifer Gommerman, professor of immunology in U of T’s Temerty Faculty of Medicine and leader of the saliva testing effort.
“Our study suggests saliva may serve as an alternative for antibody testing. While saliva is not as sensitive as serum, it is easy to collect.” The saliva assay was developed at U of T while a team at Lunenfeld-Tanenbaum, led by senior investigator Anne-Claude Gingras, who is also a professor of molecular genetics at U of T, executed the serum assay.
“The LTRI platform for detection of antibodies in serum, or blood, is incredibly robust and well suited for assessing the prevalence of infection within the community,” said Gingras. “This is another tool that can help us better understand and even overcome this virus.”Original Source