[Translated from French]

Scientific evidence about the long-term effects of COVID-19 continues to accumulate. Two new studies involving hundreds of thousands of people suggest that SARS-CoV-2 infections can cause cognitive decline.

Researchers at Imperial College London recruited nearly 113,000 Britons previously infected with the COVID-19 virus for their study. These individuals engaged in various cognitive exercises to assess their memory and their faculties of concentration and attention. Their results were compared to those of people never infected.

The results, published in the New England Journal of Medicine, show that the coronavirus is believed to impair cognitive abilities and the intelligence quotient (IQ).

Even people who had few symptoms initially had lower results than those who had never been infected. In participants who recovered in less than a month (and had mild symptoms during the active phase of infection), the researchers noted an average loss of 3 IQ points compared to the never-infected group. This decrease is considered a mild cognitive decline.

In participants with long COVID (those who had post-infection symptoms for three months or more), there was an IQ drop of about 6 points.