Herd immunity update

"The researchers say their findings suggest people who have been infected with Covid-19, even if they experienced only mild symptoms, have protection against reinfection of SARS-CoV-2, the coronavirus that causes Covid-19, for “at least up to 40 days after the onset of signs.” However, it remains unclear whether this protection lasts for longer.

Immunity to any virus isn't simply black-and-white, but rather a spectrum – one can experience a continuum of infection levels from zero to full infection and everything in between. Even if you have antibodies to a specific virus, it doesn’t necessarily mean you are totally protected from the infection. Equally, levels of immunity can progressively slip as time goes on. Furthermore, immunity is not all about antibodies; the immune response to a pathogen also relies on a well-trained army of B cells (the white blood cell that secretes antibodies) and T-cells (which directly kill cells that have been infected by an invader).

This new research looks promising but is not a guarantee that people who have had a mild Covid-19 infection will have any lengthy, meaningful immunity to reinfection. The team is hoping to investigate this further by looking at the patients’ antibody response and its associated neutralization capacity in the long term."

https://www.iflscience.com/health-and-medicine/people-who-have-had-mild-covid19-appear-to-have-some-immunity/?fbclid=IwAR27vWCmVyf4MlfPYrhfRuoqUyZR2vybAAqTxOYaOVVgEnA20Qqddx30Th0