Economic and social aspects of taeniasis.

TAENIA SAGINATA is a parasite of hu-mans, where its adult form is a large tapeworm in the small intestine, and of cattle, where its larval form is a small cysticercus in the muscles. Man can only acquire the infestation by eating raw beef. Cattle can only acquire the cysticercus by consuming ova from human excreta. Humans, as a rule, are concerned only with their own infestation. They seldom consider the affected cattle and the great epizootic which rages in the herds of Northern Ireland and elsewhere. Cysticercosis bovis is bad for cattle health, and bad in particular for the trade in fat cattle. Any beast with a cysticercosis bovis infestation suffers in greater or lesser degree in health. The loss to milk production cannot be known, but a figure can be arrived at for fat cattle. In 1961 the percentage of cysticercosis bovis in cattle slaughtered in Northern Ireland was 2.3. In 1962 it was 2.5. In 1963 it was 2.8, with a range from 10 per cent. at one abattoir to .1 per cent at another. If we take the gross total output of fat cattle and calves as 438,000, and the rate of infestation as 3 per cent., the number infested will be 13,140. If one reckons the loss per affected beast on slaughter at £10, the total loss to Ulster in 1963/64 on that account is £131,400. If we take the figures for cattle slaughtered in 1963/64-171,000, and cattle shipped 124,267, the total is 295,267. In that case the number infested may be reckoned at 9,000 and the loss at £90,000. In either case this is a substantial national loss. A loss of £100,000 would be .36 per cent. of the gross Northern Ireland output of fat cattle and calves in 1963/64. This is too much to lose because of a single infestation. This loss of money is unnecessary. The epizootic in cattle can be abolished if the medical profession undertake to abolish human infestation. If that is done, then there would be no ova to contaminate pasture and water, and the cattle could not acquire the disease. Early diagnosis and prompt, efficient treatment are necessary, and both are easy and cheap. Moreover, numerically, it is not difficult. It is doubtful if there are more than 100 adult taeniae saginatae in Belfast. It is doubtful if there are more than 500 in Northern Ireland. To disinfest one case in hospital could not cost more than £15. To disinfest 500 cases would cost £7,500. Once the existing human cases were all disinfested, the charge would not recur. This is much cheaper, and more healthy, than to accept the infestation and share the loss. Let us get rid of it, and share the profit. Eire must do the same, because large numbers of store cattle are imported yearly for fattening in Northern Ireland. In 1964, 127,000 imported cattle, presumably all from Eire, received fat stock certificates. If a reservation must be made it is this-that the life cycle of T. saginta is truly as described in the standard parasitological accounts. There is no real reason to doubt them. Adult taenia saginata is not observed in any host other than man. It has not been observed in cattle. Only a large host could accommodate such a large worm. Segments are not seen in the faeces of any domestic or farm animal.