Phylogenetic analysis traces CRF01_AE’s decades-long spread across Asia

A Bayesian phylogeographic analysis of near-complete HIV-1 genome sequences traces CRF01_AE from Central Africa to major epidemics across Southeast and East Asia. The study identifies a decades-long transmission corridor linking Africa, Thailand and China, with the recombinant form introduced into Thailand in the early 1980s before reaching China through repeated cross-border movements.

The researchers reconstructed the evolutionary and geographic history of CRF01_AE using viral sequences and Bayesian phylogeographic methods. Their analysis indicates that, after entering Thailand in the early 1980s, CRF01_AE spread across Southeast Asia and into China. Repeated movement across national borders was central to this continental expansion.

The reconstructed history also shows that many lineages circulated for years before detection, revealing substantial cryptic transmission before surveillance recognized them. Once established, transmission clusters persisted for decades and sustained local epidemics long after their initial introduction. These findings demonstrate that the regional spread of CRF01_AE unfolded over many years rather than through a single detectable event.

By showing that viral lineages remained undetected for years and that transmission clusters continued for decades, the study provides a historical context for the emergence of CRF01_AE across Asia. The authors identify early molecular surveillance and coordinated regional strategies as important for detecting emerging lineages and interrupting cross-border transmission.

Subject of Research: Evolutionary and geographic spread of HIV-1 CRF01_AE from Central Africa across Asia

Article Title: Global spread and evolutionary trajectories of HIV-1 CRF01_AE: Insights from phylogenetic analysis

Article References: Li, X., Jorgensen, D., Liu, H., Nie, Q., Bates, C., & Gu, Q. (2026). Global spread and evolutionary trajectories of HIV-1 CRF01_AE: Insights from phylogenetic analysis. PLOS One, 21(10), e0360404. https://doi.org/10.1371/journal.pone.0360404

Image Credits: AI Generated

DOI: 10.1371/journal.pone.0360404

Keywords: HIV-1, CRF01_AE, phylogenetics, Bayesian reconstruction, viral evolution, genome sequencing, molecular surveillance, cross-border transmission, Southeast Asia, China, Thailand, Central Africa