COVID is caught twice in 20 days by a woman, setting a new record.
According to Spanish researchers, a healthcare worker tested positive for the omicron strain of the coronavirus just 20 days after contracting an infection caused by the delta variant.
Researchers will present the case study of the 31-year-old woman, who was fully vaccinated and boosted, at this year’s European Congress of Clinical Microbiology and Infectious Diseases, which will be held in Portugal this coming weekend.
The shortest known time between infections is 20 days.
The woman first tested positive in a PCR test during a staff screening at her workplace on Dec. 20 of last year. Before returning to work, the patient, who had not developed any symptoms, self-isolated for ten days.
She developed a cough and fever and felt generally unwell on Jan. 10 this year, just 20 days after first testing positive, and did another PCR test. This was also a plus.
The patient had been infected by two different strains of Covid-19, according to whole-genome sequencing. The woman’s first infection was with the delta variant, and her second, in January, was with the more transmissible omicron variant, which the World Health Organization had identified as a variant of concern last November.
Omicron is much more infectious than delta, according to studies, and it can evade people’s immunity from previous infections, as well as the Covid vaccine, which protects against severe infection, hospitalization, and death.
The omicron variant has since been supplanted by a subvariant of the strain known as BA.2, and other variants, including one dubbed XE, have also emerged.
Dr. Gemma Recio of the Institut Català de Salut in Tarragona, one of the study’s authors, said the case highlights the omicron variant’s ability to evade previous immunity acquired either through natural infection with other variants or through vaccines.
“In other words, even if they have been fully vaccinated, people who have had Covid-19 cannot assume they are immune to reinfection,” Recio said.
“However, both previous infection with other variants and vaccination appear to partially protect those with omicron from severe disease and hospitalisation.”
She said the case highlighted the importance of virus genomic surveillance in fully vaccinated people and in reinfections because “monitoring will help detect variants with the ability to partially evade the immune response.”
The European Congress of Clinical Microbiology and Infectious Diseases selection committee has reviewed the material, but there is no full paper at this time, and the authors have not yet submitted the work to a medical journal for publication.
The case highlighted how Omicron could “evade the previous immunity acquired either from a natural infection with other variants or from vaccines,” according to study author Dr. Gemma Recio, who presented the findings at the European Congress of Clinical Microbiology and Infectious Diseases.
“In other words, even if fully vaccinated, people who have had COVID-19 cannot assume they are immune to reinfection,” she explained.
“However, in those with Omicron, both previous infection with other variants and vaccination appear to partially protect against severe disease and hospitalisation,” Dr. Recio added.
She said it was critical to track reinfections in people who had been fully vaccinated, as it would help in the search for vaccine-resistant variants.
It has been discovered that the Omicron variant of the Covid variant is capable of evading immunity resulting from a previous infection or two vaccine doses.
The risk of reinfection with the Omicron variant is 5.4 times higher than with the Delta variant, according to a study from Imperial College London.