A recent study published in the journal Nature Medicine has revealed that SARV-CoV-2, the virus responsible for COVID-19, can cause health damage even in individuals who show no symptoms of the disease. The study, conducted by scientists at the Medical University in Chongqing, China, found that individuals who had contracted the virus without showing any symptoms had a lower level of immunity against the virus than those who had experienced symptoms. The study also found that lung damage caused by the virus in asymptomatic individuals was limited to small areas, which meant that no noticeable symptoms or restrictions were experienced.
The study involved 37 individuals who had contracted the virus but had not shown any symptoms. The virus was only detected in these individuals because of contact tracing and genetic testing. Although all participants felt healthy, laboratory tests showed elevated levels of C-reactive protein in 11 of the 37 individuals, and CT scans revealed signs of pneumonia in 11 others. The study found that 30 of the 37 asymptomatic patients had developed IgG antibodies three to four weeks after contracting the virus, but the number of antibodies was significantly lower than in symptomatic patients. The study also found that the number of antibodies decreased more rapidly in asymptomatic patients, leading to the conclusion that long-term immunity is unlikely in mild cases of the disease.
According to Michel Nussenzweig, a scientist at the Rockefeller University in New York, the lack of neutralizing antibodies in asymptomatic cases may be due to the immune system having already fought off the infection without needing to activate antibody production. The study’s authors suggest that the findings have implications for the development of vaccines and the management of the pandemic. The study highlights the importance of testing and contact tracing in identifying asymptomatic cases and preventing the spread of the virus.
