The greatest mortality occurs between the fourth and sixth week. The causes of death may be exhaustion from choleraic discharges, dyspnoea, and inability to swallow. In protracted cases inanition results.

Autopsies show that but few organs aside from the muscles are affected by anatomical lesions. Cohnheim observed fatty degeneration of the liver and enlargement of the mesenteric glands. The muscles present the appearances of lesions of acute interstitial myositis around the capsules of the embryos.


The affection differs from acute rheumatism in the absence of swelling in the joints and the much greater local tenderness along the surface of the muscles. The latter are exceedingly painful both to pressure and voluntary movement. The disease in its protracted form has been mistaken for enteric fever, and undoubtedly it has many times escaped detection. The most valuable features in determining the diagnosis are the extreme tenderness to pressure of the muscles, their swollen condition, and the general oedema and dyspnoea. Under cocaine anaesthesia a small piece of muscle may be excised from the arm or thigh for microscopic examination. Osier advises searching the stools for the parasites, which may be found with a low-power lens as glistening threads.


The basis of treatment is to at once evacuate the alimentary canal, providing the fact of eating the infected meat is known within a day or two. Diarrhoea should not be checked. If constipation exists, a strong purgative of calomel and jalap or castor oil should be administered. When systemic symptoms develop, the treatment must be purely symptomatic, because there is no known remedy which will reach and destroy the trichinae. Every effort must be made to support the strength of the patient until the embryos have become encysted, after which the acute symptoms will subside of themselves.