Patient critical after reinfection with S.African variant: study

Doctors in France are treating a critically ill patient infected with the South African coronavirus variant, four months after he recovered from COVID-19, in what study authors said was the first case of its kind.

The 58-year-old man had a history of asthma and initially tested positive for COVID-19 in September when he presented to medical staff with a fever and shortness of breath.

The symptoms persisted only for a few days, and the man tested negative for COVID-19 twice in December 2020.

However, he was admitted to hospital in January and diagnosed with the South African variant.

The patient's condition worsened, and he is currently in a "critical condition" on a ventilator.

"This is, to our knowledge, the first description of reinfection with the South African (variant) causing severe COVID-19, four months after a first mild infection," said authors of a study published this week in the journal Clinical Infectious Diseases.

The 501Y.V2 coronavirus variant emerged late last year in South Africa and immediately provoked alarm among disease specialists.

It has eight key mutations, one of which affects the virus' spike protein, making it more effective at binding to human cells and therefore more infectious.

Vaccine manufacturers Pfizer/BioNTech and Moderna say their mRNA vaccines retain their effectiveness against the South African variants and another that emerged last year in Britain.

However a study last week showed that AstraZeneca's vaccine failed to prevent mild and moderate cases of infection of the South African variant.

"The impact of 501Y.V2 mutations on the effectiveness of vaccines developed based on earlier SARS-CoV-2 strains is still unknown," said the authors of the reinfection study.