Dirofilaria immitis and Dirofilaria repens: Investigating the Prevalence of Zoonotic Parasites in Dogs and Humans in a Hyperenzootic Area
Dimitris Dimzas, Georgios Aindelis, Andronki Tamvakis, Sapfo Chatzoudi, Katerina Chlichlia, Maria Panopoulou and Anastasia Diakou
This study was conducted to assess the prevalence of zoonotic parasites, specifically Dirofilaria immitis (heartworm) and Dirofilaria repens, in dogs and humans within the hyperenzootic region of Thrace, northeastern Greece. The research was carried out within the "One Health" framework, emphasizing the interconnectedness of animal, human, and environmental health.
The study involved collecting 604 blood samples from dogs and 625 serum samples from humans residing in the Thrace region. The dog samples were tested for Dirofilaria spp. microfilariae using the Knott’s test and for D. immitis antigen using a commercial serological test (DiroCHECK®). The human samples were analyzed using Western blot techniques to detect antibodies specific to D. immitis and D. repens.
The findings revealed that 29.3% of the dogs were infected with at least one species of Dirofilaria, with 28.6% testing positive for D. immitis and 1.2% for D. repens. The highest prevalence was observed in the regional unit of Evros, where 36.1% of dogs were infected. Among humans, specific antibodies were detected in 6.7% of the samples, with 3.8% testing positive for D. immitis and 2.9% for D. repens. The study found that the proportion of human infections was 23.4% of the corresponding canine infections in the area.
In dogs, certain factors such as male gender, outdoor lifestyle, and residence in the Evros region were significantly associated with a higher risk of infection. However, in humans, no significant correlations were found between demographic factors and the risk of infection.
The study emphasizes the importance of monitoring and controlling Dirofilaria infections, given their significant prevalence in both dogs and humans in Thrace. It advocates for the implementation of preventive measures, increased awareness among medical professionals, and the development of diagnostic tools to manage these zoonotic infections effectively. The research underscores the need for a comprehensive One Health approach to address zoonotic diseases, particularly in regions with high infection pressure like Thrace, and calls for ongoing surveillance and a coordinated response to mitigate the public health impact of Dirofilaria infections.
