Stevenson (Brit. Med. Journ., 1892) records a case of sardine poisoning which proved fatal, and in which the tissues post-mortem were found to be emphysematous. He extracted an alkaloid from some of the sardines, and the stomach contents; it was highly toxic and proved fatal to rats.
It is most probable in poisoning by tinned fish that the contents of the tins have become contaminated with bacteria before being sealed up.
Shell-fish may become contaminated with bacteria and cause true infections in people who eat them. Typhoid fever has been carried in this way by oysters, and probably cockles. The fish may develop toxins and prove poisonous, and as an example of this mussels produce a powerful toxin—mytilotoxine—while they are alive, which gives rise to a serious illness termed mytilotoxismus. There are three quite different classes of symptoms induced by poisonous mussels. In one the symptoms are principally those of acute gastro-enteritis; in another skin eruptions are the principal feature; and the third is known as mytilotoxismus paralyticus, in which there is great disturbance of the cerebro-spinal nervous system, with paralysis. The two former groups of symptoms are due to putrefactive processes in the mussels, but the third or paralytic group is due to the alkaloid mytilotoxine, which is not a product of putrefaction, as it is not found in mussels that have been allowed to decay.
There is nothing to evidence the idea that mussels absorb metallic poisons—e.g. copper—from the bottoms of vessels.
Poisoning by Milk and
Milk Products
The term milk poisoning or galactotoxismus is used here to indicate the results following the drinking of milk infected with saprophytic toxicogenic bacteria, and which are mainly responsible for the high mortality from “summer diarrhœas” of artificially-fed infants. One of the products of these bacterial infections of milk is the alkaloid tyrotoxicon. It has been isolated by Vaughan from cheese, and has also been found in ice-cream, frozen custards, and cream puffs. Vaughan, however, asserts that it is not the one most frequently present, nor is it the most actively poisonous. There are others which he considers are poisonous albumins (Vaughan, Twentieth Cent. Pract. Med., vol. xiii.).
The symptoms of poisoning by tyrotoxicon are mainly those of acute gastro-enteritis, and comprise constriction of the fauces, nausea and vomiting, sharp griping intestinal pains, headache, thoracic oppression, chilliness, dizziness, and purging. In severe forms exhaustion, subnormal temperature, coma, collapse, and death may follow.
TRICHINIASIS
This disease is due to the introduction of the Trichina spiralis into the human body. The encysted worm is found embedded in the fibres of all the striped muscles of the trunk and limbs, and even in the heart, where it appears in the form of white ovoid bodies or capsules, the capsules being sometimes calcareous. The worm passes the greater part of its existence in the chrysalis state in the muscular system of one animal, and only reaches its mature condition in the stomach of another. Virchow and Zenker assert that the trichina not only frequently presents itself in the human organism, but that this organism is most favourable for its full development. Once in the stomach, the period of incubation is about three to eight days, and then propagation rapidly begins and continues, so that Dr. Kellen estimates that in about seven days after the ingestion of half a pound of meat the stomach and intestines may contain thirty millions of the worms. The worms when introduced into the stomach leave their capsules, become free, produce young, and these leave the stomach through its coats for the muscles, where they become encysted. The trichina is most frequently found in pork, seldom in sheep, horses, or oxen—the last being the most free.
Symptoms.—Intestinal irritation, loss of appetite, sickness, malaise, general weakness of the limbs, and diarrhœa. The eyelids swell as well as the joints, the skin is bathed in cold, clammy sweat, and a low form of fever sets in. Death may be due to peritonitis, paralysis of the muscles—the result of their destruction—or to irritative fever. During the perforation of the coats of the stomach and bowels by the worms, the mucous membrane becomes inflamed, pus is formed on the surface, and the stools become bloody.