On December 9th , the Brazilian Ministry of Health (MoH) recognised the first case of reinfection in the country.
A 37-years-old healthcare worker resident in Northeast Brazil presented two clinical episodes of COVID-19 in June and October 2020, that were confirmed by RT-PCR in samples collected 116 days apart. Whole-genome sequencing revealed that the two infections were caused, respectively, by the two most prevalent SARS-CoV-2 Brazilian lineages B.1.1.33 (primo-infection) and B.1.1.28 (reinfection).
Bayesian analysis indicates that the reinfection probably occurred between September 14th to October 11th, a few days before the second confirmed clinical episode of COVID-19, thus excluding the possibility of viral co-infection followed by long-term viral persistence. Notably, the B.1.1.28 virus detected at reinfection corresponds to a new emergent Brazilian viral lineage, initially detected in the Rio de Janeiro state, containing the mutation E484K in the Spike protein.