Migratory birds often bring along dangerous stowaways on their epic journeys: ticks. These blood-sucking arachnids can transmit serious pathogens, including Lyme disease, anaplasmosis, and Powassan virus infection. Now, ticks that ride on birds may be spreading more easily and establishing themselves in new locations due to climate change. For more information on the survey results, please visit The study was published Nov. 18 in the journal Frontiers of Cellular and Infectious Microbiology.
“If conditions are favorable for tropical tick species to colonize areas where they were previously inhospitable, they could introduce new diseases,” said study co-author Shahid Karim, a biologist at the University of Southern Mississippi. said. stated in a statement.
unwanted travel companion
Ticks are one of the most effective on the planet disease vector. These can link humans and livestock to diseases that normally only occur in the wild, such as Lyme disease. Ticks can also bite birds, especially migratory birds that travel thousands of miles. This hitchhiking allows ticks to travel long distances.
[Related: You’re less likely to get a tick bite if you steer clear of these spots.]
Rising global temperatures due to climate change are making it easier for some tick species to become invasive species. This can also happen very quickly. for example, asian longhorn mite (Haemaphysalis longicornis) was first detected in New Jersey. 2017 It is now found in 14 more states.
“The geographic distribution of many tick species is rapidly changing,” said study co-author Lorenza Beatty, a biologist at Georgia Southern University. stated in a statement. “For some migratory non-native ticks, global warming could create conditions in their northern destinations.”[s] Same as normal range. Warm climatic conditions and the presence of suitable vertebrate hosts for all life stages of the tick would increase the likelihood of establishment. ”
bird watching
in new researchthe research team investigated the spread of ticks through migratory birds. The team set up nets at six locations along the northern Gulf of Mexico where the birds typically rest. Each bird was fitted with a numbered identification band, measured, body scanned and scrutinized for ticks. If a tick was found, the arachnid was preserved for later DNA analysis to confirm the species and determine what pathogen it was carrying.
then the team divided the birds into three categories– Residents, short-distance immigrants, long-distance immigrants. They also mapped the geographic distribution of each bird species to understand where they pick up ticks. These maps highlighted how far ticks can be transported. The average spray distance reached 3,100 miles (5,000 kilometers).
However, the number of mites was found to be quite low. Nearly 15,000 birds were sampled, approximately 2,000 of which were collected multiple times, but only 421 ticks were collected from 164 birds. meanwhile 18 types of ticks were identifiedjust four species accounted for 81 percent of the ticks identified by scientists. Short-distance migrants carried more ticks than long-distance migrants, and some of the tick samples were Neotropical species not established in the United States.
under the microscope
The team then analyzed the bacteria the ticks were carrying. Francisella Bacteria were the most common. These endosymbiotic bacteria help the tick function, but some species can cause diseases called mites. tularemia. higher level Francisella Tick bacteria are associated with lower levels of two other bacteria.rickettsia or Cutibacterium.
rickettsia species was the second most prevalent bacterium. These bacteria are caused by fever or rash It depends on the species. This may indicate that they have a symbiotic relationship with ticks that is currently unknown to scientists. To suck the blood of migratory birds that travel long distances, large amounts of energy from ticks To maintain attachment.
It is possible that rickettsia These species may help ticks cope with energy loss due to locomotion. some species rickettsia It can cause human diseases such as spotted fever. But scientists still don’t know whether non-native ticks can transmit these diseases to humans.
According to the teamFurther research is needed to better understand the impact of tick spread by birds. Future studies could investigate whether birds act as carriers of tick-borne diseases when they are not transmitting ticks.
“Not only do these ticks have the potential to introduce new pathogens, but if they are able to establish themselves in the United States, they have the potential to further transmit pathogens that are already present in this country, or to maintain pathogens in wildlife reservoirs and spread infections.” It could be a source,” Karim said. .
The best ways to protect yourself from tick-borne diseases are to wear long sleeves when outdoors, use a good insect repellent, and check for ticks after going outside or spending time in tick-infested areas. is to do.
