Use Of New Drug Against Hydatids

Press, Volume CV, Issue 31016, 23 March 1966, Page 18

Use Of New Drug Against Hydatids

Large-scale trials with a new non-purging, anti-hydatids drug, bunamidine hydrochloride, are being made in some areas to determine the costs involved in its widespread application, says the National Hydatids Council.

The new drug may prove a valuable aid in the eradication campaign by reducing to controllable levels the infection in dogs in areas where the incidence is high and has not responded to standard procedures. It could also have application as an annual single treatment for city pet dogs which do not have access to farmlands.

But, the council says, no known drug, however effective, can prevent dogs from becoming infected with hydatid tapeworms. The cornerstone of the whole eradication campaign must remain the dog owner’s responsibility to prevent dogs having access to infection. There can be no substitute for proper dog housing, control, and feeding, and the proper disposal of offal and dead stock. The National Hydatids Council, in conjunction with the Hydatids Research Unit of the Medical Research Council and the Wellcome Foundation, has carried out extensive trials during the last year with bunamidine hydrochloride to ascertain its efficiency in treatment of dogs carrying hydatid tapeworms and other associated tapeworms of economic importance and to determine safe does rates.

“Not Easy Answer”

These trials have demonstrated that, while the drug has a relatively high efficiency, it does not provide a perfect or easy answer to the problem of hydatids control, the council says. The cost of the drug and the necessity for frequent dosing of dogs would greatly increase the cost of any control scheme.

The basic principles on which any control scheme must be founded are that dog owners must ensure that dogs do not become carriers of hydatids tapeworms that will reinfect pastures with eggs, and that clean pastures will lead to the production of farm stock, particularly sheep, that are free from hydatid cysts capable of infecting dogs. Complete control has to be achieved before eradication can begin.

In the conditions which still apply in some areas and certainly on many individual farms in New Zealand, where the risk of reinfection of dogs is frequently present, bunamidine, or any similar drugs, would need to be administered at least every six weeks to produce the maximum degree of control that can be obtained by therapeutic means.

“Ineffective Control"

The council has approved the use of bunamidine in several areas so that further evaluation of its effectiveness can be made under varying conditions and so that the costs and administrative problems can be assessed. Such trial use of the drug has been approved for the east coast area of the North Island, where present control measures have proved ineffective, and for the Waimea county, where a large portion of dog owners have expressed their desire for a six-weekly dosing system.

A trial in the Dunedin city area to assess the usefulness of bunamidine in treatment of the wide variety of dogs kept as pets in towns and cities is also in progress.

A further trial In a small country area may also be arranged. but until results from the current series of trials are fully evaluated no further extension of the use of the new drug is contemplated, the council says.