SWINE FEVER

Timaru Herald, Volume CXXXVII, Issue 19512, 10 June 1933, Page 18

SWINE FEVER

ITS HISTORY AND SYMPTOMS I Speaking to members and their friends at the Central Club, Mr A. M. Paterson, M.R.C.V.S.. related the history of the disease known as swine fever, and described the methods adopted in New Zealand for its eradication. An outbreak of swine fever in the Wellington district had surrounded this disease with some degree of passing interest, and no doubt many people were wondering if it w r as likely to prove a menace to human life. The fact that swine fever was confined exclusively to pigs, should allay all fear on that point, said Mr Paterson.

Swine fever was first identified in America, less than a hundred years ago, but it was almost certain that it existed from time immemorial, although it was not known. In 1862 it was introduced into England, and from England it was conveyed to Sweden, doubtless through the traffic in breeding stock. In 1887. it found its way into Denmark, thence to Germany, Austria and Hungary, and ultimately into every agricultural country in the world, including our own. It was, however, quickly eradicated from New Zealand. The last two outbreaks in this island occurred at Mataura and at Riversdale, and they were cleaned up without the slightest difficulty, as the present outbreak would be when all affected farms had been finally located and quarantined. Like all other infectious and contagious diseases, swine fever was usually caused by a germ, w’hich, however, was usually accompanied by several other germs, each of which set up a disease of its own, so that swine fever, like many other germ diseases, was a compound of many diseases, and this made it all the more difficult to diagnose with certainty, and to treat with confidence.

For a number of days, usually from five to ten (the so-called period of incubation), the germs multiplied with great rapidity, and produced increasing quantities of their specific toxin or poison; and, when this toxin had been produced in a sufficiently large quantity, the body of the victim was so affected that, it manifested the first symptoms of the The whole system being poisoned, the animal w T as markedly ill. It stood W’ith its back arched, and a discharge issued from its eyes and nostrils, and sometimes red blotches appeared on the skin. Farmers having pigs showing these symptoms should report at once to the nearest Stock Inspector. It was difficult to diagnose this disease with certainty, so. the usual plan adopted by practitioners, was to make a post mortem, to make sure whether the characteristic lesions, or tissue changes, were present or not. If they w'ere present. they appeared as small, button-like ulcers scattered j about the viscera; and, if they were found at the junction of the small | bowel and the caecum, or blind gut. it would be held that an undoubted case of sw'ine fever had been found. No treatment for this disease was ever j undertaken, as it w’as found to be far I more profitable to slaughter all affectI eel animals, than to quarantine all "contacts.” to feed them. slaughter them w'hen fat, inspect them, and, if they w’ere free from all traces of the disease, to pass them. None of the flesh of affected pigs was ever passed as fit for human food. In countries like America, where the ! disease had become indigenous, preventive measures were practised on an | extensive scale; but. in New Zealand. ! we did not require to go to such exj nen.se. We eradicated the disease, j and then trusted to our system of j quarantine and port inspection, to keep it out of the country. In the | east, this method proved highly satisj factory, and would doubtless be con- | tinued, with such modifications as new knowledge might suggest. j But, notwithstanding ail precautions, said Mr Paterson, an occasional out- \ break may occur, for the germs sur- ! vive in the soil, it may be for years. and it was conceivable that infection 1 might be carried from previously infected areas, although all reasonable I precautions were taken to prevent any j such mishap. The soil was heavily | limed and ploughed under, and orders i were given that no pigs be allowed to run anywhere near the danger zone. | until it was thought safe. The I land was then ploughed up again, if | required for cropping, purposes, hut ! the farmer was cautioned of the I danger, even then, of allowing pigs to wander on to the old run. where the germs might still be active