When you hear someone discussing a changing climate, you probably have a few things come to mind. Rising sea levels, melting glaciers, more intense rainstorms and more frequent heat waves may cross your thoughts. But now, something else may come to light.
Two University of Michigan researchers say an increased risk of avian influenza transmission in wild birds can be added to the list.
Population ecologists Pejman Rohani and Victoria Brown used a mathematical model to explore the consequences of altered interactions between two species as a result of climate change.
They found that climate change could upset the interactions between ruddy turnstone shorebirds and the horseshoe crabs. The crabs provide the majority of the bird's food during their annual stop at Delaware Bay. The bay is a major estuary of the Delaware River bordered by New Jersey to the north and Delaware to the south.
Disruptions caused by climate change along with the well-timed interplay between the birds and crabs could lead to an increase in the avian influenza infection rate among the birds and resident ducks of Delaware Bay, according to the researchers.
The Delaware Bay is a crossroads for many bird species traveling between continents. This could cause an increase in the avian infection rate thus helping spread novel subtypes of the influenza virus among North American wild bird populations, according to Rohani and Brown.
As for humans, the researchers said their finding don't indicate and increased risk to their health.
"But every single pandemic influenza virus that has been studied has included gene segments from avian influenza viruses," said Rohani, a professor of ecology and evolutionary biology, a professor of complex systems and a professor of epidemiology at the School of Public Health. "So from that perspective, understanding avian influenza transmission in its natural reservoir is, in itself, very important."
Even though avian flu viruses do not normally infect humans, there have been sporadic human infections with avian flu viruses. Since 2003, more than 600 cases-including more than 300 deaths-of human infection with highly pathogenic avian influenza A H5N1 have been reported worldwide, according to the World Health Organization, according to the researchers.