Microscopy and Serological Assessment for Heartworm Infection in Cats in Makati, Philippines Showing Clinical Signs of Dirofilariosis

BACKGROUND The sole published data on feline heartworm infection in the Philippines was reported four decades ago. The study therefore endeavoured to assess and provide an update on the current status of heartworm infection in domesticated feline species using serologic and parasitological examination methods. METHODS A total of 46 males and 54 females cats showing clinical signs of dirofilariosis from Makati City, Philippines were subjected to two antigen-based test kits and a microfilaria concentration method. RESULTS The most commonly observed clinical sign was coughing while exercise intolerance was seldom seen. Age groups ranging from 1 to 4 years old exhibited majority of the clinical signs whereas the 8.1 to 12 years category had the least. The results from the different detection methods employed revealed that none of the animals were positive for circulating microfilaria and no detectable levels of heartworm antigens were obtained. CONCLUSION The presence of associated clinical signs is not an outright indicator of feline dirofilariosis and may be indicative of the rarity of heartworm infection in cats in Makati, Philippines.