Media release

From: The Royal Society

Mercury and avian influenza - Avian influenza antibody prevalence increases with mercury contamination in wild waterfowl

Environmental contaminants affect wildlife by reducing survival and reproduction, but some contaminants can also suppress the immune system, making infection more likely. Ducks, which are exposed to mercury in their environment, are also hosts for avian influenza, so understanding whether contaminants influence influenza infection is important for wildlife, livestock, and human health. Here, we found that ducks with higher mercury concentrations were more likely to have antibodies to influenza, indicating infection within the past year. These results suggest that environmental contamination could affect animal health not only directly, but also by altering prevalence of infectious diseases.

• Mercury and avian influenza - Mercury pollution may make wild waterfowl more vulnerable to avian influenza. Blood mercury concentrations and influenza infection markers were measured in 11 migratory duck species overwintering in California. Ducks with the highest mercury levels were five times more likely to have influenza antibodies, indicating a recent infection. Environmental contamination’s effects could extend well beyond the polluted area if they increase the prevalence of infectious disease in highly mobile hosts, the authors said.