Specifically, the researchers found that clusters of Hendra virus spillovers occur following years in which the bats experience food stress. And these food shortages typically follow years with a strong El Niño, a climatic phenomenon in the tropical Pacific Ocean that is often associated with drought along eastern Australia. But if the trees the bats rely on for food during the winter have a large flowering event the year after there’s been a food shortage, there are no spillovers. Unfortunately, the problem is that “there’s hardly any winter habitat left”, says Raina Plowright, a disease ecologist and study co-author at Cornell University in Ithaca, New York.
The study is “absolutely fantastic”, says Sarah Cleaveland, a veterinarian and infectious-disease ecologist at the University of Glasgow, UK. “What’s so exciting about it is that it has led directly to solutions.” Cleaveland says the study’s approach of looking at the impact of climate, environment, nutritional stress and bat ecology together could bring new insights to the study of other pathogens, including Nipah and Ebola, and their viral families. The study provides “a much clearer understanding of drivers of this issue, with broad relevance to pandemics elsewhere”, says Alice Hughes, a conservation biologist at the University of Hong Kong. “The paper underscores the enhanced risk we are likely to see” with climate change and increasing habitat loss, she says.