Ghent mouse study: two mild Covid infections leave traces in the brain's memory centre

Researchers at Ghent University and the Flanders Institute for Biotechnology (VIB) infected mice twice with different variants of the coronavirus. The infections were mild and went almost unnoticed. They then examined what had changed in the brain, VRT NWS and The Brussels Times report, citing Belga.

In the hippocampus, a brain region important for memory, the researchers found fewer connections between nerve cells. In mice genetically predisposed to Alzheimer's they also saw more amyloid plaques, the protein clumps typical of the disease. They found no clear inflammatory response in the brain. The researchers say signals from other parts of the body may trigger the changes. Researcher Lien Van Hoecke says even mild infections can leave a mark on brains that are already vulnerable.

The team stresses the limits of the work: it involved only mice, follow-up was short and effects on memory were not tested. Whether something similar happens in humans is not yet clear. Further research must show what repeated infections do in the long term and whether flu causes comparable changes.