Scientists analyze dispersal of parasites by birds in the Americas

(Physorg; 15 March 2017)

Monitoring and understanding the dispersal of potentially pathological microorganisms are constant concerns for sanitary and epidemiological authorities worldwide. The risks involved are evident, given the possibility of outbreaks of emerging diseases in humans or in domestic animals and livestock.

Cross-border transfer of pathological agents can occur not only through human mobility but also through the movement of wild animals. Among the leading suspects to be monitored are migratory birds, which transport parasites over long distances, but little is known about how parasites are transferred by flocks of birds in wintering or breeding sites.

A pioneering study was based on an analysis of malaria parasites in blood samples taken from more than 24,000 migratory and resident birds in 23 countries throughout the Americas.

“It’s the largest study ever performed on the parasitology of migratory birds in the Americas,” said biologist Maria Svensson-Coelho, researcher at the Federal University of São Paulo’s Environmental, Chemical & Pharmaceutical Science Institute (ICAQF-UNIFESP) in Brazil, where was responsible for processing some of the samples.

“Hundreds of species of birds leave their tropical or subtropical wintering ranges every year to spend the summer in high-latitude breeding ranges, returning to low latitudes at the end of the mating season,” Svensson-Coelho said. “These species are exposed to different parasites in their boreal or temperate breeding areas and subtropical or tropical wintering areas. They may disperse parasites between these areas.”