To date, studies have found that antibodies against the new coronavirus offer varying levels of immunity from infection. "T cell memory might reach a more stable plateau, or slower decay phase, later than the first 6 months post-infection", the study states.
They found 91.1% of those who had recovered from COVID-19 had antibodies against the virus months after infection. However, most studies indicated that patients without symptoms still have two key advantages: they may be able to clear the virus faster from their body, and they could be infectious for a briefer period of time. Of these, 79 focused on SARS-CoV-2, 73 of which included only hospitalized patients; eight in SARS-CoV and eleven in infection with MERS-CoV. Another study from researchers at the University of Washington indicates that immunity lasts for at least three months.
The scientists believe a more detailed understanding of the pathogenesis based on this research may contribute to the development of drugs to prevent the development of severe COVID-19.
A new study conducted by researchers from the University of Oxford and Oxford University Hospitals NHS Foundation Trust found that people who contract COVID-19 are "highly unlikely" to get reinfected for at least six months.
The Times also points to another recent study that showed that survivors of SARS, also caused by a coronavirus, still carry important immune cells 17 years after being infected.
The study is the result of a collaboration led by Associate Professor Menno van Zelm, from Monash University and was published on Monday in the preprint server, MedRxiv. Part of the reason researchers studied all three diseases was to determine why COVID-19 has spread more rapidly than the earlier diseases.
COVID-19 continues to have an enormous impact on daily lives.
The imminent vaccination against COVID-19 is the world's only hope to defeat the pandemic that started early this year and practically put the whole world on hold, but even before the candidate vaccines haven't been developed, there are doubts when it comes to how long people can stay immune to the virus. This research analyzed genetic data from bronchoalveolar lavage fluids from lungs of patients with COVID-19 from Wuhan, China to characterize the activity and genetic characteristics of the CD4+ T cells present.