Weekly updates: 2022 West Nile virus transmission season (europa.eu)
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SARS-CoV-2 variants of concern as of 12 January 2023
A highly virulent variant of HIV-1 circulating in the Netherlands
SCIENCE 3 Feb 2022 Vol 375, Issue 6580 pp. 540-545
Highly virulent variant of subtype-B HIV-1 detected in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log10 increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV—CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences—is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence.