Blacklegged ticks (Ixodes scapularis) are the primary vector of Lyme disease to humans, but researchers at Old Dominion University in Virginia are focusing on another tick, Ixodes affinis, even though it doesn't bite people.

In their paper published in the Journal of Medical Entomology, "New records of Ixodes affinis parasitizing avian hosts in southeastern Virginia," Erin Heller and co-authors document Ixodes affinis parasitizing five songbird species on which it had not previously been recorded. This is important because birds are able to travel long distances, and bring tick hitchhikers with them.

As the range of Ixodes affinis expands northwards and overlaps more with that of the human-biting blacklegged tick, the authors predict that having two competent tick vectors may increase transmission of the pathogen throughout the system and lead to an increase in the number of Lyme disease cases in humans.

This study adds to a growing body of evidence that indicates that in order to understand the spread of Lyme disease, researchers must consider the ecology of all of its various hosts and vectors. Ixodes affinis and its various feathered hosts may prove to play a significant part in the story of this potentially debilitating disease.