Study pinpoints ‘win-win’ solutions to protect human health and conserve ecosystems

A far-reaching review of academic papers and reports evaluated 46 proposed “win–win” solutions for reducing human infectious disease burdens and advancing conservation goals, which now can be explored on a publicly available website. The study highlights diverse and widespread bright spots where there could be opportunities to simultaneously safeguard human and ecosystem health.

Nearly 30 researchers from across the United States and overseas conducted the study, which appears in Lancet Planetary Health. The interdisciplinary team included academic researchers, practitioners at government and nonprofit organizations, and veterinarians. UC Berkeley School of Public Health contributors include Assistant Professor Laura H. Kwong, Professor Justin V. Remais, and doctoral candidate Christopher LeBoa.

Skylar Hopkins, an assistant professor of applied ecology at North Carolina State University and corresponding author of the study, said the interdisciplinary group worked on this synthesis for four years. They painstakingly searched the existing academic literature for potential solutions and then developed a new process for determining whether a specific “win-win” solution is safe, feasible, and cost-effective. They found that the solutions have varied levels of evidence for success; some have strong support already and others are ripe for further study.

“We like to think of these solutions like options on a bespoke menu. To select and design a solution that meets your needs, you’re going to need a lot of information. So we provide an evidence summary for each solution,” Hopkins said. “We also created a decision process that anyone can follow, so researchers and decision makers can design their own solutions or evaluate whether an existing solution will work in their situation.”

But Hopkins said that it wasn’t easy to evaluate some of the potential solutions.

“Sometimes the evidence for a potential solution conflicted,” Hopkins said. “One study would suggest that an intervention would reduce human disease burdens and another study would suggest that the same intervention would increase human disease burdens. Potential solutions could also have trade-offs or collateral impacts, where the intervention was good for some people but not others.” The team had to develop a method for quantifying evidence diversity, consistency and applicability to deal with these complications.

The list of 46 solutions shows only one with “high” evidence for both positive human health and conservation implications: vaccinating dogs to reduce rabies transmission to wildlife and people. Several of the solutions focus on domestic cats and dogs as disease reservoirs.

“This research team reflected the exceptional interdisciplinarity that will be necessary to solve the complex conservation, sustainability and environmental health challenges that lie before us,” said Justin Remais, Professor and Chair of Environmental Health Sciences at Berkeley Public Health and co-author of the study.

The team set out to find examples of potential win–win solutions that safeguard human and ecosystem health. They found that the 46 potential solutions cover six of the world’s seven continents – all but Antarctica – and included many of the world’s major known pathogens and methods of disease transmission. The solutions also tackle most of the world’s most pressing environmental problems, including land-use change due to agriculture, urbanization, resource exploitation and invasive species.

Twenty-seven of the solutions center on conservation efforts that also had human health benefits; many involve managing species, like the snail parasites that contaminated village water sources. Thirteen of the solutions are not specific to human health or conservation yet they touch both sectors. Replacing wood-burning stoves with cleaner stoves is proposed to reduce deforestation and smoke-related ailments, the researchers say.

“The future of environmental health will link together the mutual missions of environmental protection, resource management, conservation, sustainable development and population health,” said Remais. “This research marks a major step forward for the joint analysis of actions we can take to improve health while protecting key environmental resources.”

“Policymakers are looking for opportunities to simultaneously advance multiple sustainable development goals, like ‘ensuring healthy lives and promoting well-being for all’ and ‘conserving life on land and below water.’ That’s important work, but it can feel abstract or intangible. We hope that this study brings those efforts to life with real-world examples,” Hopkins said.