Pandemics in amphibians, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), have resulted in biodiversity loss at a global scale. Genomic data suggest a complex evolutionary history of Bd lineages that vary in pathogenicity. Africa harbors a significant proportion of global amphibian biodiversity, and multiple Bd lineages are known to occur there; yet, despite the decline of many host species, there are currently no described Bd-epizootics. Ghose et al. (2023) describes the historical and recent biogeographical spread of Bd and assess its risk to amphibians across the continent of Africa. Their study provides a 165-year view of host-pathogen interactions by (i) employing a Bd assay to test 4,623 specimens (collected 1908–2013); (ii) compiling 12,297 published Bd records (collected 1852–2017); (iii) comparing the frequency of Bd-infected amphibians through time by both country and region; (iv) genotyping Bd lineages; (v) histologically identifying evidence of chytridiomycosis, and (vi) modeling future Bd risk. They found a pattern of Bd emergence beginning largely at the turn of the century. From 1852–1999, Bd prevalence is low (3.2% overall) with limited geographic spread, but after 2000, prevalence sharply increases (18.7% overall) with wider geographic spread and multiple Bd lineages that may be responsible for emergence in different regions.They found Bd risk to amphibians to be highest in much of eastern, central, and western Africa. The study documents a largely overlooked yet significant increase in a fungal pathogen that could pose a threat to amphibians across an entire continent and emphasizes the need to bridge historical and contemporary datasets to better describe and predict host-pathogen dynamics over larger temporal scales.

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