Dog A-Z > W > Worms > Hydatid disease

Hydatid Disease

Hydatid Disease can be fatal in humans.  Humans get it from dog’s faeces and handling dogs, dogs in turn get it from sheep.  It is caused by a tapeworm called Echinococcus granulosus.

Life cycle of the Echinococcus granulosus

1. Eggs are laid by the tapeworm

2. Eggs are passed in dog faeces and can contaminate grass and garden vegetables

3. Eggs are picked up by grazing sheep and cattle

4. Each egg hatches in the intestine of the sheep and the early stage of the tapeworm is carried in the bloodstream to the liver, lungs, brain and elsewhere where they develop into liquid-filled cysts containing many young tapeworms

5. If a dog is fed infected meat or allowed to scavenge on infected carcasses, then the young tapeworms are released into the dogs’ system and grow in the intestines, producing more eggs and risking the further spread of infection.

Humans can pick up the infection from infected dogs, very often from ingesting eggs via hand to mouth transfer. Children are particularly at risk from this. Infection can also be spread by ingesting food, water or soil which is contaminated by infected dog faeces.

Why should dog owners be aware of this disease?

Although dogs show no serious effects, this disease can cause serious illness in humans.  Symptoms vary depending where in the body the tapeworm cysts are located. Breathing difficulties, swelling of the abdomen, symptoms similar to a tumour, general illness, or even death may result.

Surgery is not always effective because cysts can easily burst, releasing thousands of immature worm heads into the body. This can cause extreme shock and further problems when the worm heads develop into new cysts. There are currently no effective drug treatments or vaccines to combat Hydatid Disease in humans.

Precautions to take with your dog

• Always wash hands after handling dogs and ensure children do so too

• Do not allow dogs to lick faces as this can allow the direct transfer of tapeworm eggs

• Pick up your dogs faeces and dispose of it safely to reduce contamination of the ground

• Worm your dog every six weeks with a wormer containing Praziquantel and is only available through your vet. This is the only tapewormer known to be 100% effective against Echinoccocus. Consult your vet to agree a regular worming programme

• Any meat you feed your dog must be well cooked

• Never allow your dog to scavenge on or be fed raw possibly infected carcasses.  Your dog should not be left to roam in the countryside without supervision

• If you live in a rural area, report all animal carcasses to your Local Authority for proper disposal

• Always wash fruit and vegetables before eating

Can all breeds be infected with Echinococcus?

Yes, but the Border collie is thought to be especially susceptible, although this may merely reflect their level of exposure.

The Welsh Assembly Government is planning an eradication campaign from January 2008.  It is anticipated this campaign will last for 10 years.  For further information on this campaign please email endemics@wales.gsi.gov.uk

For more information about this disease please speak with your Vet regarding your dogs treatment or your GP regarding human health, particularly if you think you may be at risk.