Monkeypox is a rare zoonotic disease caused by the Monkeypox Virus (MPXV) from the Orthopoxvirus genus, which includes the variola virus, the causative agent of smallpox.

MPXV is endemic in West and Central African countries, and the rare reports outside these regions have been associated with imports from those endemic countries. The MPXV outbreak across multiple countries was first identified in May 2022, with more than 2,500 confirmed cases reported worldwide as of Jun. 18, 2022.

On Jun. 24, 2022, researchers at the Portuguese National Institutes of Health published a paper on Nature Medicine, a leading medical journal,: Phylogenomic characterization and signs of microevolution in the 2022 multi-country outbreak of monkeypox virus in Nature Medicine.

The study revealed that the virus strains responsible for the May 2022 monkeypox outbreak are a distinct and well-characterized branch that diverges from the viruses found in endemic African countries between 2018 and 2019. This may represent the recent evolutionary changes of the virus. The study also suggested that MPXV continued to evolve during human-to-human transmission, which may explain why the transmission rate of the strain increases.

To identify the source of the monkeypox outbreak in 2022, the team reconstructed the MPXV genome sequences associated with this outbreak. Their analysis showed that this MPXV belongs to clade 3 and that this outbreak most likely has a single origin. Notably, the 2022 MPXV diverges from the related 2018–2019 viruses by a mean of 50 single-nucleotide polymorphisms (i.e., genetic variants), which is significantly higher than the normal level seen in orthopoxviruses. The authors suggest that such a divergent branch might represent accelerated evolution. Subsequent analysis also revealed the initial signs of ongoing virus evolution, including 15 single-nucleotide polymorphisms, minor genetic variants, and deletions that occurred in the human-to-human transmission during this outbreak.

While further research is needed, these findings offer valuable insights into the possible mechanisms of virus evolution and potential genetic targets for virus adaptation in humans. This data helps to clarify the evolutionary path of monkeypox virus strains during the 2022 outbreak.

Note: This article is reprinted for the purpose of conveying information, and the content does not represent the position of this site. Media or individuals who do not wish to be reprinted may contact us, and we will delete them immediately.