Derry City & Strabane - Environmental Health
Health & Community Wellbeing




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Toxocara - The Facts


It is important that dog owners realize that the mess left by their dog is both a nuisance and a serious health hazard.  Dog faeces can contain a number of things which can make people ill, best known of which is the infection caused by toxocara canis.

What is Toxocara?

Toxocara canis is the common roundworm of the dog. Toxocara eggs are present in the faeces of dogs which have not been treated with the appropriate tablets. If a person comes into contact with contaminated faeces and infected eggs, usually through swallowing, there is a slight possibility of an illness referred to as toxocariasis.

What can I do to prevent anyone catching toxocariasis?

It is very easy to prevent. Worm your dog regularly. If in doubt, consult your veterinary surgeon. Always clean up your dog's faeces and dispose of it. Wash your hands after petting, feeding or cleaning up after your dog. This is very important for children. Also, train your dog at an early stage to 'go' on command at home.

How common is toxocariasis?

It is very rare. There are approximately two cases each year due to infection per million people. On the rare occasions when human infection occurs, it usually causes mild, flu-like symptoms. Toxocara antibodies are present in fewer than two in 100 healthy adults in the UK who have previously been exposed to infection with no ill effects.

Can toxocariasis cause blindness?

Total blindness from Toxocara infection is exceptional. It is rare even for the sight of one eye to be totally lost, though vision can be impaired. However, even one case is too many. It is so simple and easy to prevent following the regular worming of dogs and cats.

Are all dogs faeces infectious for toxocariasis?

Freshly passed faeces are not a Toxocara hazard. Any eggs in the faeces take two or three weeks to mature and require very specific conditions before becoming infectious.

Can I treat the garden to kill any remaining Toxocara eggs?

Most responsible pet owners do worm regularly so there should not be a problem. However, simple hygiene measures should always be advised. For example, wear gloves when gardening and teach children to wash their hands after playing, before eating and if their hands are dirty. Many normal gardening activities will greatly lessen the chance of significant contamination i.e. digging and turning the earth and the composting of grass clippings and other vegetable matter. In situations where contamination of soil has occurred some eggs may remain infectious for up to three years, so simple hygiene measures should be followed to avoid potential risk.

My child may have eaten some dog faeces - what should I do?

There is very little risk of Toxocara infection. However, you are advised to take your child along to your doctor for advice and any appropriate treatment.

How often should I worm my dog/puppy?

It is important to worm pregnant or nursing bitches and especially young puppies, which are more likely to be handled by young children. Adult dogs should be wormed every three months to prevent infection. Puppies should be wormed from the age of two weeks, every two weeks, until the age of 12 weeks. Pregnant and lactating bitches also need frequent working. Bitches should be wormed before mating, after the first 45 days of pregnancy, after giving birth and whilst weaning pups. Seek the advice of a health professional if you are in any doubt about the advisability of worming, the age that worming should be carried out and the dosages involved. As with any treatment read the product label carefully.


Contact Details

Dog Control Team
 📞  02871253253 


 🐶 Leslie Bernat, Dog Warden
 📞 028 71 253 253

 🐶 Kieran Graham, Dog Warden
 📞 028 71 253 253

 🐶 Sean Stewart,  Dog Warden
 📞 028 71 253 253