A Spanish health worker tested positive for the Omicron COVID-19 variant 20 days after having the Delta variant – the shortest gap between infections yet to be recorded, it has been revealed.
The case, which is being presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) in Lisbon, Portugal, involves a 31-year-old woman who was fully vaccinated and had received a booster jab 12 days before testing positive for COVID-19 in a PCR test.
She did not develop any symptoms, but self-isolated for ten days before returning to work.
On January 10, 2022, she developed a cough and fever and felt unwell, and a PCR revealed she was COVID positive again.
Whole genome sequencing showed she had been infected by two different strains of SARS-CoV-2: Delta in December and Omicron in January.
Study author Dr Gemma Recio, of Institut Català de Salut, Tarragona, Spain, says: “This case highlights the potential of the Omicron variant to evade the previous immunity acquired either from a natural infection with other variants or from vaccines.
“In other words, people who have had COVID-19 cannot assume they are protected against reinfection, even if they have been fully vaccinated.
“Nevertheless, both previous infection with other variants and vaccination do seem to partially protect against severe disease and hospitalisation in those with Omicron.
“This case also underscores the need to carry out genomic surveillance of viruses in infections in those who are fully vaccinated and in reinfections. Such monitoring will help detect variants with the ability to partially evade the immune response.”
ePoster L0438, which has been peer reviewed by the congress selection committee, is being presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) Annual Meeting. There is no full paper yet and the work has not been submitted to a medical journal.
Leave a Reply