Lyme disease causes flu-like symptoms. (Image: Getty)
Migrating birds are bringing more disease-carrying ticks into the northern hemisphere, according to a new study.
Scientists fear this could lead to an increase in Lyme disease in Britain, which causes flu-like symptoms and can make people very sick if not treated quickly.
Climate change is being blamed for extending the range of migrating birds and allowing ticks previously unable to survive in colder conditions to reproduce and flourish in northern Europe.
Ticks from warmer countries can carry pathogens not historically seen in colder regions, meaning that people could be infected with novel tick-borne diseases.
These can be passed to humans, and pets like cats and dogs, by the parasites on migratory birds – which can travel up to 3,000 miles.
Scientists say the changes to global temperatures caused by climate change are now making it easier for some ticks to establish themselves as invasive species.
This can happen quickly, as with the Asian long-horned tick which was first detected in New Jersey in the US in 2017 and has since been found in 14 other states.
Dr Lorenza Beati, of Georgia Southern University, the co-author of the study, said: “Geographic distribution is changing very rapidly in many tick species.
“For some migrating exotic ticks, global warming may create conditions at their northern destination that are similar to their usual range.
“If warmer climatic conditions are combined with the presence of suitable vertebrate hosts for all tick life stages, the chance of establishing their presence is going to increase.”
In the study of tick dispersal through migrating birds, scientists set up nets at six locations where birds stop to rest along the northern Gulf of Mexico.
When ticks were found, these were removed and preserved for later DNA analysis to confirm the species and identify the micro-organisms they carried.
Almost 15,000 birds were sampled and 421 ticks were collected from 164 birds, with 18 different species of ticks.
Dr Shahid Karim, of the University of Southern Mississippi, lead author of the study, said: “If conditions become more hospitable for tropical tick species to establish themselves in areas where they would previously have been unsuccessful, then there is a chance they could bring new diseases with them.”