Continent-wide recent emergence of a global pathogen in African amphibians
Introduction Emerging infectious diseases are increasingly recognized as a global threat to wildlife. 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 histor...
Saved in:
Published in: | Frontiers in conservation science Vol. 4 |
---|---|
Main Authors: | , , , , , , , , , , , , , , , , , , |
Format: | Journal Article |
Language: | English |
Published: |
Frontiers Media S.A
15-03-2023
|
Subjects: | |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Introduction
Emerging infectious diseases are increasingly recognized as a global threat to wildlife. 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. Here, we describe the historical and recent biogeographical spread of
Bd
and assess its risk to amphibians across the continent of Africa.
Methods
We provide 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) using a habitat suitability model to assess future
Bd
risk.
Results
We found a pattern of
Bd
emergence beginning largely at the turn of the century. From 1852–1999, we found low
Bd
prevalence (3.2% overall) and limited geographic spread, but after 2000 we documented a sharp increase in prevalence (18.7% overall), wider geographic spread, and multiple
Bd
lineages that may be responsible for emergence in different regions. We found that
Bd
risk to amphibians was highest in much of eastern, central, and western Africa.
Discussion
Our study documents a largely overlooked yet significant increase in a fungal pathogen that could pose a threat to amphibians across an entire continent. We emphasize the need to bridge historical and contemporary datasets to better describe and predict host-pathogen dynamics over larger temporal scales. |
---|---|
ISSN: | 2673-611X 2673-611X |
DOI: | 10.3389/fcosc.2023.1069490 |