Worms. Nasty little devils that they are. No dog owner wants to know their beloved, cute canine friend has become host to these unwanted guests. Further, worms can cause serious – even life threatening – health problems. So how often should you worm?
Worm infection from pets at home can potentially lead to serious health risks both for animals and humans.
Many people do not realise that some parasitic worms can cause disease in humans – the so called ‘zoonotic diseases’ – and cats and dogs can pick up worms from just about anywhere in their normal environment, especially the garden, the park and the countryside.
They don’t even have to roll around in the grass to pick them up, just snuffling in the grass or licking their feet clean after a walk can do it.
In recent years there has been a growing recognition of the potential for animals to transmit diseases to humans, with worm-related problems being high on the list of zoonotic diseases.
Of these, Human Toxocariasis and Human Hydatid Disease are perhaps the best-known.
“Pets are human companions and the part they play as they accompany us through life is growing in significance,” said Sabrina Stroud, a dog worming expert with a leading animal health company.
“Keeping this close relationship healthy is not just an obligation to our animal companions. It also protects people from the transmission of disease pathogens. And to that end, we are constantly developing new products and forms of administration.”
Human Toxocariasis is divided into three syndromes: Ocular Larva Migrans, Visceral Larva Migrans and Covert Toxocariasis and may give rise to signs such as visual impairment, coughing, hepatomegaly and fever.
Previously it was thought that Human Toxocariasis was contracted via the ingestion of worm eggs from contaminated soil. Recently a study has been published which demonstrates that direct contact with worm eggs in the coat of dogs may be responsible for causing toxocariasis in man *.
Human Hydatid Disease is due to the presence of hydatid cysts in a human, and these may be found in the liver, lungs and other sites within the body.
Common types of worms found in the UK include roundworms, tapeworms, whipworms and, in particular at this time of year, hookworms.
Uncinaria stenocephala, or Northern Hookworm to give it its common name, is found in the small intestine. In heavily infested pups it can have some nasty results, such as diarrhoea, anorexia and lethargy.
There is a sharp rise at this time of year as the maturation of the larvae is temperature-dependent. This worm is primarily a problem in kennels, and the usual route of infection is by mouth.
There is evidence to show that 62 per cent of foxes in the UK and 92 per cent of foxes in Ireland are infected with Uncinaria stenocephala. Therefore a country walk or even being in the garden can carry the risk of infection to pets.
The majority of puppies contract some form of internal parasite either before or shortly afterbirth. Although this may sound repulsive to you, it’s a normal part of being a dog. There is no need to be excessively concerned, provided you have your puppy checked and treated promptly. Left untreated, intestinal parasites can cause serious harm.
Therefore, it’s essential to bring along a small, fresh sample of your puppy’s stool when you make your first veterinary visit. When the stool is dissolved, eggs or parasites from this sample will be clearly visible under a microscope. Do not assume your puppy has no intestinal parasites simply because no worms have shown up in the stool.
Adult worms often live exclusively within the intestinal tract; the tiny eggs they release serve as the only clue to their existence. Furthermore, other internal parasites, even as mature organisms, never reach a size visible to the naked eye. Let your veterinarian discover which type, it any, of these parasites inhabits your puppy’s system and treat it accordingly.
Regular worming protects the health of your pet, your family and the public
All animals (including humans) can carry worms at some stage in their lives. These worms are often very small, making it difficult to determine whether your pet is infected.
Most such parasites are closely adapted to their host and in moderate numbers usually cause few visible effects although the damage they cause produces harmful localised injury (i.e. damage to the gut).
The adverse effect of worms is generally greatest in younger animals, however, the major health problems that worms can cause normally result from the worm getting into the wrong host (e.g. a child) where severe consequences can sometimes occur (such as blindness).
Dogs and cats naturally carry two major types of worms – roundworms and tapeworms. Some have complex life histories and may infest more than one type of animal in their life cycle. A good example of this is the flea tapeworm. Here the maggot-like flea immature stage eats the eggs produced by the tapeworm. The egg hatches within the flea and develops in a dog or cat’s intestine when the flea is swallowed during grooming. It is possible that young children can catch this tapeworm from accidentally eating fleas originating on a pet.
The large roundworms of dogs and cats produce thousands of eggs and are commonly seen in puppies. Ingestion of these eggs releases the immature worm, which leaves the gut and migrates around the body of the animal eventually ending up in the intestine, where they develop into egg laying mature adult worms. In older animals they usually stop migrating and become stuck in tissues as cysts where they do little harm. In pregnant bitches these dormant stages re-activate and migrate to the mothers intestine, the milk glands and also directly into the puppies in the womb.
All tapeworms are caught by a pet following the ingestion of raw animal flesh (e.g. mice or birds) containing tapeworm cysts.
One tapeworm of dogs found in sheep rearing areas of the UK is of particular concern. The worm lays eggs that, when eaten from contaminated pasture, develop into large cysts in sheep (hydatid disease). If a human accidentally eats one of these eggs then a similar cyst can develop in the liver or lungs, requiring extensive surgery and (very rarely) proving fatal.
Be a Responsible Pet Owner
Fortunately there is plenty one can do to eliminate the risk of worms…
Remember to dispose of dog faeces safely, cover sand pits when not in use (to prevent cats using them as litter trays), and keep control of your dog in the countryside.
Most importantly, the British Small Animal Veterinary Association recommends that pets be wormed four times a year.