Are mosquito coils, vaporisers and repellents safe for pets?

A 2012 systematic review in Parasites and Vectors describes how mosquito coils, vaporiser mats and emanators protect against bites through the spatial action of vapour or airborne pyrethroid particles, and notes that these products dominate the mosquito control market. The coils, mats and liquid vaporisers found in most Indian homes work the same way: the active ingredient is printed on the pack.

The Merck Veterinary Manual says that among pets, cats appear to be more sensitive to pyrethroid toxicity. Signs it lists include salivation, vomiting, hyperexcitability, tremors, seizures, difficulty breathing and weakness, and in severe cases death. That is why the room, the dose in the air and the species all matter.

Heartworm, a worm that lives in the heart and lung blood vessels of dogs and less often cats, is spread by mosquito bites and is widespread in tropical and sub-tropical regions; a 2015 study found it in dogs in north-east India. Prevention is a prescription decision for your vet, who will choose a product and schedule for your dog. Keeping mosquitoes out of the home with screens and nets protects people and pets at once, without putting any chemical on the animal.

Mosquito season also overlaps with tick season, and flea and tick products for dogs are where the most serious mistakes happen in multi-pet homes. In the Australian adverse-event reports reviewed in 2008, insecticide poisoning in cats usually followed an owner putting a dog spot-on on the cat; cats were also at risk from grooming or close contact with a recently treated dog.

Write it in the care sheet: which repellent you use, in which room, whether windows stay open, and that the cat or bird stays out of that room. Leave your vet's number and the name of any flea, tick or heartworm product your vet has prescribed, with the dates it is due. A Petym sitter follows the pet's plan as you write it and logs medicines as they are given.