Borrelia burgdorferi Sensu Lato Spirochetes in Wild Birds in Northwestern California: Associations with Ecological Factors, Bird Behavior and Tick Infestation

Newman et al. investigated the birds’ roles as bridging vectors for subadult Ixodes pacificus ticks and as potential host for the Lyme disease spirochete B.burgdorferi sensu stricto in north-western California. Lyme disease is an infectious disease caused by Borrelia bacteria, which is spread by ticks. In North America, Lyme disease is caused by B.burgdorferi sensu stricto, which are mainly from the nymph stages of Ixodes scapularis and Ixodes pacificus. Ixodes pacificus is known to infested more than 100 species of lizard, birds and mammals in California, and Ixodes scapularis has similar impact on the East Coast. While most researches have focused on the role of mammals as spirochete reservoir hosts, birds are potentially important hosts because of their species-rich and ecologically diverse. Birds’ dispersal distances are generally much larger than for mammals and they migrate annually. Thus, they may have an impact on the geographic spread of ticks and borrelia bacteria.