COVID-19 antibody testing and ‘immunity certification’

What we know and don't know about SARS-CoV-2 protective immunity

SARS-CoV-2 is a new virus and knowledge about the human immune response is still developing, including how and why immune response differs between individuals. Biological markers for increased susceptibility to COVID-19 are also being sought. While evidence shows that most people who are infected develop antibodies that are specific to the virus, some apparently recover without showing an antibody response. While antibodies are likely to be involved in protecting against future infection, the presence of antibodies cannot be said to equate to ‘immunity.’ Furthermore, the duration of any protection they confer is, so far, unknown.