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Updated: Jul 16, 2025
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Vaccinia Virus Infection & Temporal Analysis of Virus Gene Expression: Part 1
Published on: April 8, 2009
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Distinct monkeypox virus lineages co-circulating in humans before 2022
Nnaemeka Ndodo1, Jonathan Ashcroft2, Kuiama Lewandowski3
1Nigeria Centre for Disease Control, Abuja, Nigeria.
Nature Medicine
|September 14, 2023
Summary
Multiple monkeypox virus (MPXV) lineages circulated in Nigeria for years before 2022, showing adaptation potential. Genomic data reveals mutations, including in the A.2 lineage, highlighting sustained human-to-human transmission and viral evolution.
Area of Science:
- Virology
- Genomics
- Epidemiology
Background:
- The 2022 global mpox outbreak highlighted gaps in understanding monkeypox virus (MPXV) human transmission and adaptation.
- The evolutionary link between the 2017 Nigerian outbreak and the 2022 global mpox emergence was unclear due to limited genomic data.
Purpose of the Study:
- To investigate the genomic diversity and evolutionary history of MPXV in Nigeria between 2018 and 2022.
- To identify the origins of exported MPXV lineages, including the A.2 lineage.
Main Methods:
- Whole-genome sequencing of 18 MPXV isolates from southern Nigeria (2019-2020).
- Phylogenetic analysis to determine lineage relationships and evolutionary pathways.
- Identification of specific mutations, including those associated with APOBEC3 activity.
Main Results:
- Multiple MPXV lineages co-circulated in Nigerian humans for several years prior to 2022.
- The A.2 lineage, previously exported independently, originated in Nigeria and persisted through human-to-human transmission for over two years.
- A lineage-defining APOBEC3-associated mutation was identified in the A46R gene of A.2 isolates, potentially affecting viral immune modulation.
Conclusions:
- MPXV demonstrates a capacity for sustained diversification and adaptation within human populations.
- Understanding pre-outbreak viral evolution in endemic regions is crucial for predicting and controlling future mpox epidemics.
- APOBEC3-mediated mutations may play a role in MPXV adaptation and evolution during human spillover events.
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