Filarial Nematodes in Dogs from the Northeast Region of Brazil

• Published in: Acta parasitologica 2024-06, Vol.69 (2), p.1115-1121
• Main Authors: Rocha, Daniely Oliveira do Nascimento, Macedo, Lucia Oliveira, Oliveira, Jéssica Cardoso Pessoa de, Silva, Samuel Souza, Cleveland, Herbert Patric Kellermann, Ramos, Carlos Alberto do Nascimento, Marques, Alex Santos, Alves, Leucio Câmara, de Carvalho, Gílcia Aparecida, Ramos, Rafael Antonio Nascimento
• Format: Article
• Language: English
• Subjects: Animal Systematics/Taxonomy/Biogeography; Animals; Antigens; Biomedical and Life Sciences; Biomedicine; Blood; Brazil - epidemiology; Coastal zone; Dirofilaria immitis - genetics; Dirofilaria immitis - immunology; Dirofilaria immitis - isolation & purification; Dirofilariasis - epidemiology; Dirofilariasis - parasitology; Dog Diseases - epidemiology; Dog Diseases - parasitology; Dogs; Ecology; Enzyme-Linked Immunosorbent Assay - veterinary; Female; Filariasis - epidemiology; Filariasis - parasitology; Filariasis - veterinary; Filarioidea - genetics; Filarioidea - isolation & purification; Health risks; Insecticides; Male; Medical Microbiology; Microbiology; Microfilariae - isolation & purification; Nematodes; Original Paper; Parasites; Parasitology; Prevalence; rRNA; Skin; Skin - parasitology; Vectors
• ISSN: 1230-2821; 1896-1851
• DOI: 10.1007/s11686-024-00834-x

Purpose Medical and veterinary filarial nematodes are transmitted by blood-feeding vectors. In dogs, these parasites are mainly represented by nematodes in which microfilariae dwell in the blood ( Dirofilaria spp. and Acanthocheilonema spp.) or skin ( Cercopithifilaria spp. and Onchocerca lupi ). The aim of this study was to determine the prevalence of these filarial infections in dogs residing in a touristic, heavily populated location in the northeastern region of Brazil. Methods Blood samples ( n  = 245) were assessed by a modified Knott test, followed by a qualitative ELISA test (SNAP® 4Dx® Plus, IDEXX Laboratory, Westbrook, Maine, USA) for the detection of antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and antigens of Dirofilaria immitis . Skin samples ( n  = 71) were microscopically examined and molecularly assessed through a PCR targeting the 12 S rRNA gene. Results Microfilariae and antigen of D. immitis were detected simultaneously in 15 (6.1%; 95% CI = 3.7–9.8) animals. Nine animals (3.6%; 95% CI = 1.9–6.8) were D. immitis antigen positive but microfilariae negative and nine other animals (3.6%; 95% CI = 1.9–6.8) were microfilariae positive but D. immitis antigen negative. D. immitis positive dogs were found in four different municipalities. No filarioids were detected in the skin after microscopical and molecular analyses. Conclusion Data from this study demonstrate that D. immitis is the main filarial nematode infecting dogs in coastal areas in northeastern Brazil. Based on the potential risk of infection in which animals are submitted, it is essential to perform tests to detect microfilariae and D. immitis antigen. Preventive measures must be adopted by using microfilaricidal compounds and anti-feeding insecticides to prevent canine infection.