Why the UK’s tick-borne disease threat is shifting

CURRENT FULL VERSION: The UK’s tick story is changing from a familiar Lyme disease warning into a broader veterinary surveillance issue. New analysis from the UK Health Security Agency’s Tick Surveillance Scheme, published in January 2026, found 3,182 tick records and 27 species submitted between 2021 and 2024, confirming that Ixodes ricinus remains the UK’s most common tick and the main vector for Lyme disease and tick-borne encephalitis. But the bigger message for practice teams is that tick exposure is being mapped more precisely, and the distribution of risk is not standing still. (researchportal.ukhsa.gov.uk)

That fits with the trajectory many veterinary parasitologists have been describing for years. UKHSA says about 4% of ticks in England and Wales are infected with Lyme-causing Borrelia on average, with some areas averaging 8% to 10%. It also notes that rising Lyme totals likely reflect a mix of improved awareness and diagnostics, as well as ecological and behavioral changes that increase opportunities for tick encounters. In England, 281 laboratory-confirmed Lyme disease cases were reported in Q2 2024, versus 253 in Q2 2023, although acute cases were lower year over year. (ukhsa.blog.gov.uk)

For small animal clinicians, Lyme disease is only part of the picture. ESCCAP UK & Ireland lists a wider set of tick-borne pathogens relevant to dogs and cats, including Babesia spp., Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Ehrlichia spp., Rickettsia spp., and others, and notes that individual ticks may carry more than one pathogen. That matters clinically because coinfections can muddy presentation and complicate interpretation of nonspecific signs such as pyrexia, lethargy, thrombocytopenia, or shifting lameness. (esccapuk.org.uk)

Babesiosis remains the clearest example of how the UK risk profile is broadening. Veterinary reports have long described most UK canine babesiosis cases as travel-associated, but published accounts of dogs in Essex with no travel history established that local transmission of Babesia canis can occur where infected Dermacentor reticulatus ticks are present. Vet Times’ clinical review describes PCR as the most sensitive and specific diagnostic approach and notes that imidocarb is used under the cascade because there is no UK-licensed canine babesiosis treatment product. Another report on the Essex cluster said PCR and DNA barcoding confirmed D. reticulatus ticks infected with B. canis canis, suggesting an endemic pocket with potential to spread. (vettimes.com)

The wider policy and public health context is moving in the same direction. APHA warned in May 2025 that practitioners across Great Britain should be alert to tick-borne disease because the geographic distribution of infection is likely to evolve with climatic and land-use changes. A 2025 BMJ news feature similarly reported that experts are linking rising tick-borne disease in the UK to climate change, which affects tick ecology, host range, and seasonality. Human occupational research from another high-incidence setting offers a useful reminder of what heavy exposure can look like on the ground: in a survey of 53 people across 46 farms in southern Vermont, 12% reported ever being diagnosed with a tick-borne disease, participants averaged three tick encounters over the previous six months, and some reported as many as 70. One farmer had developed Lyme carditis severe enough to require open-heart surgery. Taken together, those signals support a view that this is not simply a matter of more awareness, but of changing exposure patterns that could alter what first-opinion practices see over time. (gov.uk)

Why it matters: For veterinary professionals, this is a surveillance and communication challenge as much as a diagnostic one. Practices may need to think less in terms of “traditional tick areas” and more in terms of changing local ecology, imported pathogens, and year-round prevention conversations with pet parents. Dogs can act as sentinels for human exposure risk, even if they are not a direct source of Lyme transmission, and the same walks, fields, and peri-urban green spaces are shared by families and pets. The experience of farmers and other outdoor workers in high-risk settings also helps make the One Health point tangible: repeated tick exposure can be a livelihood issue as well as a clinical one. Lower thresholds for travel histories, tick checks, cytology or blood film review when babesiosis is suspected, and PCR referral in the right clinical context may become increasingly important. (vettimes.com)

What to watch: The next phase will likely be defined by whether UK tick surveillance translates into more granular veterinary risk messaging, whether known D. reticulatus hotspots expand, and whether practices begin seeing more locally acquired vector-borne disease outside established clusters. Updated UKHSA mapping, APHA alerts, and any new case reporting around canine babesiosis will be the clearest signals. (researchportal.ukhsa.gov.uk)