Robust evidence for bats as reservoir hosts is lacking in most African virus studies – a review and call to optimize sampling and conserve bats

Africa experiences frequent emerging disease outbreaks among humans, with
bats often proposed as zoonotic pathogen hosts. We comprehensively
reviewed virus-bat findings from papers published between 1978 and 2020 to
evaluate the evidence that African bats are reservoirs and/or bridging
hosts for viruses that cause human disease. We present data from 162
papers (of 1322) with original findings on (1) numbers and species of bats
sampled across bat families and the continent, (2) how bats were selected
for study inclusion, (3) if bats were terminally sampled, (4) what types
of ecological data, if any, were recorded, and (5) which viruses were
detected and with what methodology. We propose a scheme for evaluating
presumed virus-host relationships by evidence type and quality, using the
contrasting available evidence for Orthoebolavirus (formerly Ebolavirus)
versus Orthomarburgvirus (formerly Marburgvirus) as an example. We review
the wording in abstracts and discussions of all 162 papers, identifying
key framing terms, how these refer to findings, and how they might
contribute to people’s beliefs about bats. We discuss the impact of
scientific research communication on public perception and emphasize the
need for strategies that minimize human-bat conflict and support bat
conservation. Finally, we make recommendations for best practices that
will improve virological study metadata.