Did mpox Virus Circulate in West Africa Before 2022?

New Delhi, May 20 (NationPress) A recent study reveals that the virus responsible for mpox (formerly referred to as Monkeypox) was actively circulating in West Africa for approximately eight years prior to the global outbreak in 2022. This research, published in the journal Nature, emphasizes the urgency for enhanced global surveillance and medical resources in light of potential future pandemics.

Through genomic tracing, researchers estimate that the virus's ancestor first appeared in southern Nigeria in August 2014, subsequently spreading to 11 states before human infections were first reported in 2017.

"If African nations had better access to therapeutics, vaccines, and surveillance technologies, the multi-country outbreak in 2022 could have been prevented," stated Edyth Parker from the Kristian Andersen Lab at Scripps Research.

Initially, scientists believed that the unexpected number of genetic mutations in the virus indicated that mpox might have been circulating in Nigeria for a longer timeframe than previously thought. However, the lack of genomic data made it difficult to pinpoint the virus's origin.

To clarify this, the team investigated 118 viral genomes from human mpox cases in Nigeria and Cameroon from 2018 to 2023. All sequences belonged to Clade IIb, the strain of mpox endemic to West Africa.

The findings revealed that the majority of viral samples from Nigeria were linked to human-to-human transmission (105 out of 109), while only four were due to zoonotic spillover. Conversely, all nine mpox samples from Cameroon stemmed from isolated zoonotic spillover incidents.

"Mpox is no longer merely a zoonotic virus in Nigeria; it has become a significant human virus," Parker explained. "However, the ongoing zoonotic transmission poses a persistent risk of re-emergence."

The study also suggests that the ancestor of the human-transmitting mpox virus emerged in animals by November 2013, entering the human population in southern Nigeria in August 2014. It further illustrates that southern Nigeria was the primary source of subsequent human mpox cases, as ongoing human-to-human transmission predominantly occurred in the southern region.

Moreover, two zoonotically transmitted viral samples from southern Nigeria were linked to viruses from Cameroon, indicating that viral transmission is crossing borders. Overall, the study underscores the critical need for enhanced access to diagnostics, vaccines, and therapeutics in Africa, according to the researchers.