#18,226
Reports of increased spread of Mpox - even in non-endemic African nations - continued last week (see More African Nations Reporting Mpox - Africa CDC Mpox Update (Jul 30th)), raising concerns that the far more dangerous clade I virus might embark on a world tour like its less pathogenic (clade II) sibling did in 2022.
Over the past 5 weeks we've revisited this topic no fewer than 6 times, including:
Over the weekend Jon Cohen (@sciencecohen) wrote an excellent article on ScienceInsider (see Deadlier strain of mpox spreads to multiple African countries) which included the news that sequences deposited to GISAID last week indicate that some of this recent spread to Kenya & Uganda (see here) involved Clade I.
Clade I, which is endemic in the DRC, is thought to be 10 times deadlier than clade II, and a recently discovered clade Ib may be even more problematic (see Preprint: Sustained Human Outbreak of a New MPXV Clade I Lineage in Eastern Democratic Republic of the Congo).
The world expressed great surprise in May of 2022 when (then `Monkeypox') clade II began showing up in dozens of countries around the world, but in truth, we'd seen warning signs for years. Just 3 months prior, we looked at PLoS NTD: The Changing Epidemiology of Human Monkeypox—A potential threat?
Small genetic changes could favor adaptation to a human host, and this potential is greatest for pathogens with moderate transmission rates (such as MPXV) (40). The ability to spread rapidly and efficiently from human to human could enhance spread by travelers to new regions.
Whether this current surge in Mpox in Africa is prelude to another international outbreak is unknown, but we can't afford to ignore the warnings signs again.
