NEW STUDY: A Chinese study shows people infected with COVID-19 lose antibodies after only a few months.

A good summary article is here: https://www.cidrap.umn.edu/news-perspective/2020/06/chinese-study-antibodies-covid-19-patients-fade-quickly

This is observational and small but reflects both symptomatic & asymptomatic people.

If confirmed in further studies, it implies that we take prevention much more seriously until vaccines, prophylaxis & therapies advance.

Here is a link to an earlier study on how T-cells May add protection. All of these things will continually be studied and must be considered together. https://www.sciencemag.org/news/2020/05/t-cells-found-covid-19-patients-bode-well-long-term-immunity

The other thing being studies here is whether cross-immunity has and can be built from the common cold (another Coronavirus).

While no evidence yet, it could offer an explanation as to how some are more susceptible than others.