Researchers from the University of Michigan have revealed that, in addition to a plethora of other devastating effects, climate change will increase the risk of diseases including avian influenza spreading in wild bird populations.

Experts have suggested that worsening climate change will give rise to new diseases and cause existing ones to spread to new areas. Scientists have suggested that the Bluetongue virus’ progression into Northern Europe in the middle of the last decade and the recent emergence of Schmallenberg Virus in the same region could be partly caused by climate change.

Population ecologists Pejman Rohani and Victoria Brown from the University of Michigan have this week warned that similar patterns could be observed in the transmission of bird flu as the climate change progresses. The pair used a mathematical model to explore the consequences of altered interactions between an important species of migratory shorebird and horseshoe crabs at Delaware Bay as a result of climate change.

They found that climate change could upset the carefully choreographed interactions between ruddy turnstone shorebirds and the horseshoe crabs that provide the bulk of their food during the birds' annual stopover at Delaware Bay, a major estuary of the Delaware River bordered by New Jersey to the north and Delaware to the south, which is known as an avian flu hotspot.

They concluded that disruptions to the well-timed interplay between the birds and crabs, as a result of climate change, could lead to an increase in the avian influenza infection rate among ruddy turnstones and resident ducks of Delaware Bay. Because Delaware Bay is a crossroads for many bird species traveling between continents, an increase in the avian infection rate there could conceivably help spread the influenza virus among North American wild bird populations, according to Rohani and Brown.

Bird flu has cost governments and poultry producers in East Asia millions of dollars since 2005. The disease has caused the cost of poultry farming to increase whilst retail prices have fallen due to fears amongst consumers.

Pejman Rohani, a professor of ecology, evolutionary biology and epidemiology at the university’s School of Public Health commented on the findings, "We're not suggesting that our findings necessarily indicate an increased risk to human health. But every single pandemic influenza virus that has been studied has included gene segments from avian influenza viruses. So from that perspective, understanding avian influenza transmission in its natural reservoir is, in itself, very important."

Their mathematical model looked at virus infection rates in ruddy turnstones and two species of duck—mallards, which winter at the bay, and American black ducks, which live there year-round. The researchers found that if ruddy turnstones reached Delaware Bay either several weeks earlier or later than their current May arrival date, influenza infection rates in the species increased significantly, driving up the infection rates in the resident ducks as well.

Tweet