Survey of Dirofilaria immitis antigen and antibodies to Leishmania infantum and Toxoplasma gondii in cats from Madeira Island, Portugal

Authors: NEVES, MICHELLE - University Of Tras-Os-montes And Alto Douro; LOPES, ANNA PATRICIA - Animal And Veterinary Research Centre(CECAV); MARTINS, CAROLINA - Society Protecting Domestic Animals Of Funchal; FINO, RAQUEL - Society Protecting Domestic Animals Of Funchal; PAIXAO, CLAUDIA - Society Protecting Domestic Animals Of Funchal; DAMIL, LILIANA - Society Protecting Domestic Animals Of Funchal; LIMA, CLARA - Universidade Do Porto; ALHO, ANA MARGARIDA - University Of Lisbon; SCHALLIG, HENK - University Of Amsterdam; Dubey, Jitender; CARDOSO, LUIS - Animal And Veterinary Research Centre(CECAV)

Submitted to: Parasites & Vectors
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/24/2020
Publication Date: 4/21/2020
Citation: Neves, M., Lopes, A., Martins, C., Fino, R., Paixao, C., Damil, L., Lima, C., Alho, A., Schallig, H.D., Dubey, J.P., Cardoso, L. 2020. Survey of Dirofilaria immitis antigen and antibodies to Leishmania infantum and Toxoplasma gondii in cats from Madeira Island, Portugal. Parasites & Vectors. 13, 117. https://doi.org/10.1186/s13071-020-3988-4.
DOI: https://doi.org/10.1186/s13071-020-3988-4

Interpretive Summary: Madeira Island, the main island of Madeira archipelago and autonomous region, on the African plate in the Atlantic Ocean, southwest of mainland Portugal is a popular tourist attraction because of the location and mild climate. The nematode Dirofilaria immitis and protozoa Leishmania infantum and Toxoplasma gondii are zoonotic parasites which can affect domestic cats and can affect humans. The authors surveyed 141 cats and found no evidence of Leishmania infection. The prevalence of Dirofilaria was low but many cats had antibodies to Toxoplasma gondii. In the scope of clinical practice, cardiopulmonary dirofilariosis and toxoplasmosis should be included in the differential diagnosis of feline patients with clinical signs compatible with both parasitoses. Knowledge on the regional prevalence of these and other zoonotic pathogens must raise awareness and contribute to the prevention and control of animal and potentially associated human infection and disease. The results will be of interests to veterinarians, parasitologists and public health workers.

Technical Abstract: Background: Dirofilaria immitis, Leishmania infantum and Toxoplasma gondii are zoonotic parasites which can affect domestic cats. Considering the absence of published data from the local feline population, this study aimed to assess infection with exposure to these pathogens in cats from Madeira Island, Portugal. Methods: One hundred and forty-one cats were sampled at a veterinary medical centre in Funchal, from September 2018 to January 2019. Serum samples were tested for D. immitis antigen, with an enzyme-linked immunosorbent assay kit, and for antibodies to Leishmania spp. or to T. gondii, with the direct agglutination test and the modified agglutination test, respectively. Results: Five cats (3.5%; 95% confidence interval [CI]: 1.2–8.1) were positive to D. immitis; no cats were seropositive to Leishmania spp. (0.0%; CI: 0.0–2.6); and 43 cats (30.5%; CI: 23.0–38.8) were seropositive to T. gondii. Prevalence of D. immitis antigen was significantly different between cats that received ectoparasiticides and those which did not (0.0% vs. 12.2%; p = 0.009). Prevalence of antibodies to T. gondii was significantly different between juvenile and adults cats (12.8% versus 38.0%; p = 0.007). There were two cats concurrently positive to D. immitis and T. gondii, but no statistical association between these two dependent variables was found (p = 0.641). Conclusions: This is the first report of the parasites D. immitis and T. gondii in the feline population of Madeira Island, a popular touristic destination. Knowledge on the epidemiological situation of these and other zoonotic pathogens should raise awareness, both at the veterinary medical and public health levels, and contribute to promoting prevention and control.