There is this person who had two genetically different COVID-19 strains (but presumably the same serotype, there's only one serotype of COVID-19 known) for the

There is this person who had two genetically different COVID-19 strains (but presumably the same serotype, there's only one serotype of COVID-19 known) for the first and second infection, confirmed by whole genome sequencing: https://doi.org/10.1093/cid/ciaa1275 https://doi.org/10.1093/cid/ciaa1275