Ticks are notorious carriers of various pathogens that can infect both animals and humans. In the UK, red foxes (Vulpes vulpes) are frequently found in both urban and rural areas, often living at high population densities. As a result, they are commonly infested with ixodid ticks, which can transmit diseases like Babesia and Anaplasma to domestic animals and potentially to humans. A recent study by Mansfield et al. has provided new insights into the types of ticks that infest red foxes in Great Britain and the pathogens they carry.
Key Findings from the Study
This study identified three tick species commonly infesting foxes, with most pathogen detections in ticks from rural foxes, though urban foxes also showed some incidence. These findings suggest red foxes may play a significant role as carriers of tick-borne diseases across various habitats in the UK.
Tick Species Infesting Red Foxes
Researchers identified three primary tick species on red foxes in the UK:
Ixodes hexagonus was the most common, representing 73% of ticks
Ixodes ricinus made up 12% of the ticks
Ixodes canisuga accounted for 15% of the tick population.
Interestingly, most of the ticks collected were female or nymphal stages, and a few were larval stages, highlighting the potential for these foxes to be key hosts in various tick life stages.
Pathogens Detected in Ticks
This study specifically investigated the presence of Babesia and Anaplasma DNA in these ticks: Babesia DNA was found in 7% of the sampled ticks, predominantly Babesia vulpes, known to cause canine babesiosis. One tick also carried Babesia Badger Type A. Anaplasma phagocytophilum, a bacteria responsible for tick-borne fever in animals and human granulocytic anaplasmosis, was detected in 4% of ticks, exclusively in I. hexagonus. No evidence of louping ill virus, a disease that can affect sheep and other animals, was found in any of the tested ticks.
Geographic Spread and Fox Habitat
Most pathogens were detected in ticks from red foxes in rural areas, although there were some detections in ticks from semi-rural and urban foxes. This finding underscores the need for surveillance of both rural and urban fox populations as potential disease reservoirs.
Implications for Disease Transmission
With Babesia vulpes DNA detected not only in the ticks but also in the tissues of some foxes, there is a suggestion that red foxes may serve as reservoir hosts for certain tick-borne pathogens. This could increase the risk of disease transmission to other animals or potentially to humans, especially in regions with high fox populations.
Related Research
Interestingly, Terry Hooper-Scharf, an independent researcher, has been conducting a separate study on fox deaths in Bristol and has also detected Babesia in local foxes. This independent finding aligns with the results of Mansfield et al.'s study, suggesting that Babesia infection may be more widespread in UK fox populations than previously recognized.
Risks to Captive Fox Health
While the presence of Babesia and other pathogens in wild fox populations is concerning, the implications for captive foxes are equally critical. Foxes in captivity—whether in wildlife sanctuaries, rehabilitation centers, or as captive-bred pets—are often in closer proximity to humans and other animals, increasing the risk of disease transmission if they become hosts for infected ticks.
Captive foxes are at risk of contracting tick-borne diseases, which can lead to severe health complications such as fever, lethargy, anemia, and organ failure. Babesia, for instance, causes babesiosis, a disease that can be fatal if left untreated. Since captive animals are often in close quarters, diseases can spread quickly between individuals and even jump species in certain cases, endangering other vulnerable animals.
Steps Keepers Can Take to Mitigate Risks:
Regular Tick Checks and Grooming: Keepers should perform frequent checks for ticks, particularly during peak tick seasons. Special attention should be paid to areas like the ears, legs, and belly where ticks are often found.
Enclosure Maintenance: Ticks thrive in overgrown, shaded environments. Keeping enclosures well-maintained by clearing brush, tall grass, and leaf litter reduces tick habitat. Enclosure perimeters can also be treated with safe, vet-approved acaricides to reduce tick populations.
Use of Tick Preventatives: Just like with domestic dogs, foxes in captivity can benefit from tick preventatives. Consulting a veterinarian on the safest and most effective products for foxes is essential to avoid toxicity issues.
Health Monitoring: Captive foxes should undergo routine health checks, including blood tests to detect early signs of tick-borne diseases like Babesia, Anaplasma or Borrelia. Early detection is key to successful treatment and can prevent the spread of pathogens to other animals in care.
Staff Education: Educating staff and volunteers on the risks associated with tick-borne diseases and proper tick-removal techniques can help prevent disease spread within the facility.
Quarantine New Arrivals: Any new foxes brought into captivity should be quarantined and monitored for ticks or signs of infection before being introduced to other animals. This practice helps prevent the introduction of ticks and diseases to a healthy population.
Given the growing recognition of tick-borne diseases in fox populations, proper management and preventative measures are essential. Captive foxes can be protected from the potentially fatal impact of tick-borne diseases, reducing risks not only to the animals themselves but also to staff and other animals under human care.
Summary
The study by Mansfield et al. highlights the role of red foxes in the ecology of tick-borne pathogens in Great Britain, especially in rural regions. As a Lyme advocate since 2013, I know that ticks often carry several stealth pathogens simultaneously, not just one—Babesia, Borrelia, Bartonella, Anaplasma, Mycoplasma, and many others are all potential risks, so the focus on these pathogens in red foxes is something I have been anticipating for many years.
With foxes so common throughout the UK, they are our wildlife sentinels, and ongoing research and monitoring are crucial for understanding and mitigating the potential public health and veterinary risks associated with these pathogens. For keepers of captive-bred foxes, awareness and preventative measures are essential to protect both their animals and the broader environment from these hidden health threats.
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