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Mosquito larvae in my cat's water fountain!
kittyquest posted:
Help! When I went to clean my cat's water fountain tonight, I found lots of black worms (mosquito larvae, I think) swimming around in one of the nooks & crannies where water stands. I'm soaking the fountain in hot water and vinegar right now, but should I just throw it out? And, more importantly, are my cats in any danger if they ingested larvae? One of them already has a heartworm. I'm calling the vet & taking litter samples over first thing in the morning but was hoping for advice tonight because I'm really worried.
Byroney_WebMD_Staff responded:
Kittyquest, thanks so much for posting.

How are your kitties doing? What did your vet have to say? This article on Heartworm in Cats doesn't specifically mention the larvae (that I saw) so hopefully your vet can address that. I would think a thorough cleaning would get rid of any issues, but again, check with your vet for an expert answer.

Let us know how you and the kitties are doing,

Every dog has his day - but the nights are reserved for the cats ~ Unknown
Drew Weigner, DVM, ABVP responded:
Mosquito larvae will not hurt your cat but it's pretty yucky! It does show that you have a severe mosquito problem and that your cats are at risk for getting Heartworms, as one already has (they're transmitted by mosquitoes and are blood parasites, so they won't show up in stool tests.) Your other cats should be on Heartworm Preventative if they test negative. You can kill the larvae with a 10% bleach solution but don't forget to change the filter in the fountain as well.

Drew Weigner, DVM, ABVP
The Cat Doctor
Board Certified in Feline Practice


William Draper, DVM, better known as "Dr. Will," is a well-known small animal practitioner in the Atlanta, GA area. He grew up in Inglewood,...More

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