· First confirmed case of reinfection documented in a 33 year-old man in Hong Kong, who was first infected with the virus in March, and again while on holiday in Spain four and a half months later – though asymptomatic for both infections
· Genetic sequencing has identified a small number of reinfection cases with different strains
· No concrete evidence on the presence and/or duration of immunity to SARS-CoV-2 in humans
· Demonstration of PCR positivity does not necessarily indicate continued or renewed infection; it may indicate the presence of a dead virus.
· In-vitro analyses have documented the presence of SARS-CoV-2 antibodies in convalescent samples up to eight months post infection
· Only one small study in rhesus monkeys recovered from SARS-CoV-2 were not re-infected when re-challenged with SARS-CoV-2 upon recovery
· Many cases series of previously recovered SARS-CoV-2 patients re-testing positive following clinical and pathological recovery, but virus has been unable to be cultured from those patients, most remain asymptomatic and there have been no documented secondary cases arising from patients following positive re-tests
Badea, A; Lee, S; Groot, G; Takaya, S; Dalidowicz, M; Howell-Spooner, B. What is the duration of immunity for COVID-19 in previously infected patients? 2021 Jan 20; Document no.: INF090101v2 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 26 p. (CEST rapid review report)