American Heartworm Society 2005 Recommendations for Cats Updated Guidelines for Diagnosis, Prevention, and Management

摘要

There are significant differences between feline heart-worm disease and its classic canine counterpart. Although cats are susceptible hosts, they are more resistant to infection with adult Dirofilaria immitis than are dogs. Most heartworm infections in cats are comparatively light and consist of fewer than six adult worms. Although much heavier infections occur occasionally, usually only one or two worms are present, and approximately one-third of these consist of worms of the same sex. Because of their relatively small body size, cats with only a few worms are still considered to be heavily infected in terms of parasite bio-mass. Host preference by some of the most abundant vectors does favor the dog and may contribute to the lower prevalence of infection in cats. The Culex spp mosquito, which is the most common species in many urban areas, feeds on both cats and dogs without preference. The true prevalence of heartworm infection in cats is probably understated because of diagnostic limitations and the greater tendency of cats to exhibit only transient clinical signs or die without confirmation of infection. Necropsy surveys of shelter cats have placed the prevalence of adult heartworm infections at 5% to 15% of the rate in unprotected dogs in agiven area. Circulating microfilariae are seldom found in infected cats.