The US CDC has said that new genetic sequencing data indicate there are at least two distinct monkeypox outbreaks underway outside Africa. One official said that might suggest that the international spread is wider, and has been occurring for longer than has been previously realized.
Three of 10 viruses the CDC has sequenced from recent U.S. monkeypox cases — two from 2021 and eight from 2022 — are different from the viruses that have been sequenced by several countries involved in the large outbreak that is spreading in and from Europe.
The Maryland sequence (2021-11) is ancestral to most of the recently detected #monkeypox sequences, suggesting this lineage has likely been circulating in humans for months, if not longer.
It may offer hints about how mutations in this lineage have accumulated.
