Expert: Jessica - 7/24/2011

Question
Hi there, a stray cat that lives on my property had kittens that I have been caring for, two of the kittens I thought had been bitten by an older cat. I talked to someone who said it might be worms, and now doing internet research I have figured out that these two 9 wk old kittens have a bot fly, both on the left cheek. What do I do? I have had them in the house for 3 days now but when I figured out what it was I put them outside again.  Can my dog catch it from them? or my kids? Should I keep them in the house? And do I just leave it alone? What should I do? Please help me I am very upset and I dont know what to do to care for them. Thank you for your time...please help

Answer
Hi Jennifer,

Bot flies lay eggs directly on the host animals that will carry their larvae, or onto an intermediate host such as a fly, which then lands on the host (in this case, your kitty), which drops eggs onto the host. In some cases, eggs which have fallen off of a host or intermediate host can infect animals. These are the times when infection can become incidental, to other animals. Another animal can brush up against the shed eggs and pick up the infection. Or, if the animals cuddle closely when the cat has newly laid eggs on her, infection can be spread this way. Fortunately, by the time you notice a bot, any eggs from the initial infection have matured, and they are no longer infective to other animals. Bots do not climb from one animal to another.

The complication is that it's possible more eggs have been laid on the kitties in the meantime since they were still outside, meaning a new infection could have taken place. While chances of infection to your dog is minimal, it's possible. Infection to your children is almost impossible. It takes about a week for eggs to hatch, and since your children probably bathe more often than this, the eggs will be washed off before they hatch (in hot and humid weather, eggs can hatch more quickly, so frequent bathing is encouraged).

The kitties with the bots already developing (which are not in themselves contagious at this stage) should have them removed by a vet. These can be dangerous to the cats, because they can cause infection. And if they happen to die inside the warble (the lump they cause), the cat can even suffer a fatal reaction to toxins that leak from the decaying larva. Never try to remove the larvae yourself. If the larva bursts or dies, the cat is at a much higher risk for that developing that reaction and infection, and the cost of vet attention to address this will be much more.

Then, to be sure everyone is free and clear of eggs, it would be best to bathe the dog and cats. This should end your problem with bot flies, as long as everyone stays in the house. As for the dog, keeping him or her away from heavy vegetation, where bot flies/eggs/intermediate hosts are most abundantly found, should minimize his or her risk from picking anything up.

Best of luck!

Jessica