Hydatid Disease And its Prevention

Northern Advocate, 30 December 1938, Page 2

Hydatid Disease And its Prevention

The Department of Hydatid Research has circulated a folder setting out the characteristics of the hydatid disease and means whereby it may be prevented. It reads as follows. —

Start And Spread of Disease.

Hydatid disease starts with tiny tapeworms getting into the gut of dogs, usually country dogs that eat raw offal. There are many kinds of tapeworms, some of them yards in length and actually resembling tape, but the Hydatid tapeworm is only about a quarter of an inch long. It makes up for its small size by occurring in largo numbers.

The microscopic eggs of these worms are passed in countless numbers in the dogs droppings. These dangerous droppings are trampled and scattered as dust, and contaminate the nearby grass and other vegetation and water supplies. Stock animals and sometimes human beings can thus become infected as they eat and drink. Flies also may sperad infection from dogs' droppings to food stuffs. The egg-laden dust also gets on to iho hairy coat, muzzle and paws of dogs, and on to the woolly fleece of sheep. Human beings who come into close contact with these animals get their hands contaminated with Hydatid eggs, and transfer of infection from hands to mouth can easily occur. This is now regarded as the most likely path of human infection, especially in the case of children. Hydatid Cysts. It is a peculiarity of all tapeworms that they pass the worm stage of life in one animal, and a cyst or waterbladder stage in another quite different animal.

Hydatid eggs passed in the droppings of dogs, and swallowed by other animals, such as sheep, cattle, pigs, horses or by human beings undergo a transformation into hydatid cysts or water-bladders.

1 The eggs hatch out in the stomach or intestine into microscopic parasites, which penetrate deeply and settle anywhere in the body, but most commonly m the liver or lungs, where they grow in tiic course of months or years, not into worms, but into cysts or waterbladders. These cysts, at first very small, may reach the size of golf balls, cricket balls, or even footballs. Economic Loss To The Farmer. Sheep and cattle are very commonly affected with cysts in liver and lungs ‘more often than not in some' districts), and their money value is thereby lessened. Although these animals may appear healthy it is reasonable to assume that their constitution and the quality of both meat and wool may be depreciated more nr less, and quality in New Zealand products is of paramount importance. Moreover, the economic waste involved in the condemnation of millions of sheep livers I every year as being unlit for food on account of the cysts they contain must bo very considerable. ‘As a matter of fact such livers, though rcpellant. are not actually dangerous to human beings, or to any other animal except the dog, and then only if eaten raw). Illness Anti Loss of Life in Human Beings. Similar hydatid cysts in human beings cause serious and sometimes fatal illness. More than 1000 men, women and children have been treated for hydatid disease in Ibis Dominion during the last 10 years, and there have been 126 deaths.

Apart from a fatal termination it must be borne in mind that Hydatid Disease commonly leads to months or years of disability in people who should be at the most useful stage of life. In the majority of cases surgical operation is the only hope of cure. The Vicious Circle! Inside a Hydatid cyst there are a multitude of microscopic particles each furnished with booklets and suckers. These are the immature heads which grow up into adult tapeworms if they reach the intestine of a dog. If, therefore, raw cysts are swallowed by dogs, as often happens when sheep’s plucks are thrown to them for food, they again give rise to hydatid tapeworms in the dogs’ intestines and again multitudes of hydatid eggs are passed with the dogs’ droppings. Thus a vicious circle is produced and Hydatid Disease is perpetuated.

Note that the Hydatid tapeworm occurs only in the dog (or doglike animals such as the wolf, jackal, and fox), but Hydatid cysts may occur in many other animals, including sheep, cattle, pigs, horses and human beings. The cysts that are commonly seen in the muscles of rabbits, are of a different species, and cats are not liable In Hydatid Disease. Precautions. (1) Of highest importance—Never feed dogs on the raw offal (liver, lungs, plucks, lights) removed from the carcase of a sheep because that is the way to infect the dogs with tapeworms which then spread Hydatid disease among human beings and farm animals in the form of cysts. This offal can easily be made safe and wholesome by slicing it into three or four pieces and boiling it in water for ten minutes. If those in charge of dogs will not carry out this simple boiling process, then they should discard the offal altogether as food for dogs, throw it in the fire and feed their dogs on other parts of the sheep’s carcase.

(2) Dose dogs regularly every three months with the worm-destroying tablets supplied with full instructions to all owners each year at the time of dog registration. This is in accordance with the “Dog Registration Amendment Act’’ passed by the New Zealand Parliament without opposition in the year of 1937. (3) In patting or fondling dogs, handling sheep and so on, remember the risk of contaminated hands, and the possibility, especially in children, of the Hydatid eggs being transferred from hands to mouth. Make a practice of washing the hands before meals.

(4) Foodstuffs should bo protected against direct pollution by dogs and indirect contamination by flies. Salads and other vegetables that are eaten raw should be carefully washed. (5) Hydatid eggs that reach water soon sink and infection from this source is not very likely, but to be on the safe side water for drinking purposes should be boiled or filtered.

Note.—These precautions have been drawn up by the Hydatid Research Committee after consultation with the Government Departments of Health, Agriculture, and Education, and they have the influential support of Lord Galway, the Governor-General of New Zealand, and of high authorities in our pastoral industry. ,