Feline Heartworm in Clinical Settings in a High Canine Prevalence Area

Abstract

Heartworm (HTW) infection in cats is associated with persistent pulmonary pathology, even when clinical signs are absent. Treatment options for cats are limited once infected, making prevention an important topic for discussion with cat owners. In Brazil, tests to detect feline HTW infections are unavailable, likely leading to an underestimation of its impact on the wellbeing of cats. The present study investigated the seroprevalence of HTW antigen in cats living in an area with high canine HTW prevalence and investigated risk factors and clinical signs associated with HTW disease in cats from Rio de Janeiro, Brazil. Clinical examinations were conducted, and serological evaluations performed with a point-of-care test (SNAP® Feline Triple® Test, IDEXX Laboratories, Inc.). A total of 586 cats were examined. The HTW antigen seroprevalence was 1.2%. Heartworm positive results were significantly associated with vomiting and abnormal lung sounds. Results from this study indicate that cats residing in areas of high canine HTW prevalence should have HTW disease as a differential diagnosis when presenting with compatible clinical signs. Veterinarians should prioritize client education and promote regular use of effective prophylaxis to protect feline health.

Seroprevalence of Feline Heartworm in Spain: Completing the Epidemiological Puzzle of a Neglected Disease in the Cat

“…Similarly, in this study it is observed that the antibody seroprevalence of D. immitis in FeLV positive cats is significantly higher. These results contradict previous publications, which indicate a lack of relationship between positivity to feline viruses and the presence of heartworm ( 3 , 15 , 30 ). Although it could be theorized that the immunosuppression caused by these feline pathologies could favor D. immitis infection, it is necessary to carry out more studies to confirm this.…”

“…Although the distribution is well studied in the canine species, there is an important lack of knowledge in the cat; in Spain, there are only published epidemiological studies in the Canary Islands, Madrid, Barcelona and Zaragoza ( 10 – 14 ). However, it is estimated that where canine heartworm is present, feline heartworm disease is also present ( 15 , 16 ). Therefore, the objective of this study was to complete the epidemiological puzzle of feline heartworm in Spain.…”

Diagnostic Accuracy of a Point-of-Care Immunoassay for Feline Immunodeficiency Virus Antibodies, Feline Leukemia Virus Antigen, and Dirofilaria immitis Antigen

“…Our understanding of feline heartworm seroprevalence is limited; the Companion Animal Parasite Council reported 0.57% seroprevalence in the United States and 1.43% seroprevalence in Canada for 2022 [ 24 ]. Another 2022 study found a heartworm antigen prevalence of 1.2% in Rio de Janeiro, Brazil [ 25 ]. One recent study found a similar prevalence of heartworm in cats to the prevalence in high-risk dogs when using antigen and antibody testing in parallel [ 26 ].…”