Infection with SARS-CoV-2 Omicron Variant 24 Days after Non-Omicron Infection, Pennsylvania, USA

Emerg Infect Dis. 2022 Sep;28(9):1911-1913. doi: 10.3201/eid2809.220539. Epub 2022 Aug 1.


A 42-year-old man, with up-to-date COVID-19 vaccination, experienced symptomatic SARS-CoV-2 infection in December 2021. Mutation tests suggested a non-Omicron variant. After his recovery, and 24 days after the first positive SARS-CoV-2 test, he had onset of symptomatic infection with the BA.1.1 (Omicron) variant, which was confirmed by whole-genome sequencing.

Keywords: COVID-19; Pennsylvania; SARS-CoV-2; United States; coronavirus disease; respiratory infections; severe acute respiratory syndrome coronavirus 2; vaccine-preventable diseases; viruses; zoonoses.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • COVID-19 Vaccines
  • COVID-19* / diagnosis
  • Genome, Viral
  • Humans
  • Pennsylvania
  • SARS-CoV-2* / genetics


  • COVID-19 Vaccines

Supplementary concepts

  • SARS-CoV-2 variants