With the caveat that one case does not confirm a trend, we appear to have the first confirmed reinfection with (apparently, two different strains) of SARS-CoV-2, from a tweet from the University of Hong Kong. The limited details, which are carried by news.rthk.hk can be read at the link below.
Hong Kong man was reinfected with Covid: study
2020-08-24 HKT 19:09
This case first came to light last week, when a 33 year-old Hong Kong man - who tested positive for SARS-CoV-2 last spring - tested positive again after recently returning from a trip to Spain. The CHP reported that man was an IT worker who first fell ill on March 23rd, tested positive on March 28th, and was discharged on April 15th following two negative tests.
At first, it was considered possible that this patient had simply never completely cleared the virus, and therefore tested positive. But today, we learn a genetic analysis shows his current infection is genetically distinct from his April infection.
Details of this case will reportedly be published in the journal Clinical Infectious Diseases.
While this appears to prove that some individuals may be susceptible to reinfection with SARS-CoV-2 within a few months, we'll need to see substantially more documented cases before we can assume immunity wanes rapidly for the majority of the population.
That is, however, a distinct possibility that we've discussed often over the past 6 months, including in:
CDC Clarifies: Recovered COVID-19 Cases Are Not Necessarily Immune To Reinfection
Imperial College London: (REACT) SARS-CoV-2 Antibody Prevalence Study - England
Kings College: Longitudinal Evaluation & Decline of Antibody Responses in SARS-CoV-2 infection
Eurosurveillance: 2 More SARS-COV-2 Seroprevalence Studies To Ponder
The Lancet: Prevalence of SARS-CoV-2 in Spain (ENE-COVID)COVID-19: From here To Immunity (Take Two)