It has already been stated that the actinomyces fungus found in human disease is considered by authorities the same as that occurring in bovine affections. It is therefore of interest to conclude this article with a brief discussion of the disease in man and its relation to actinomycosis in cattle.
In man the location of the disease process corresponds fairly well to that in cattle. The majority of cases which have been reported in different parts of the world—and they are now rather numerous—indicate disease of the face. The skin, tongue, or the jawbones may become affected, and by a very slow process it may extend downward upon the neck and even into the cavity of the chest. In many cases the teeth have been found in a state of more or less advanced decay and ulceration. In a few cases disease of the lungs was observed without coexisting disease of the bones or soft parts of the head. In such cases the fungus must have been inhaled. The disease of the lungs after a time extends upon the chest wall, where it may corrode the ribs and work its way through the muscles and the skin. An abscess is thus formed discharging pus containing actinomyces grains. Disease of the digestive organs caused by this fungus has also been observed in a few instances.
Granting the identity of the disease in man and cattle, the question has been raised whether cattle are responsible for its occurrence in man. Any transmission of the infectious agent may be conceived of as taking place during the life of the animal and from the meat after slaughter. That human beings have contracted actinomycosis by coming in contact with diseased cattle is not shown by the cases that have been reported, for the occupations of most of the patients did not bring them into any relation whatever with cattle. While the possibility of such direct transmission is not denied, nevertheless it must be considered as extremely remote. Practically the same position is maintained at present by most authorities as regards the transmission of the disease to man by eating meat. Israel, who has studied this question carefully, found the disease in Jews who never ate pork,[5] and who likewise were protected from bovine actinomycosis by the rigorous meat inspection practiced by that race. Furthermore, it must be borne in mind that actinomycosis is a local disease, causing great destruction of tissue where the fungus multiplies, but which very rarely becomes generally disseminated over the body from the original disease focus. The fungus is found only in places where the disease process is manifest to the eye or becomes so in a very short time after the lodgment of the fungus. Only the greatest negligence would allow the actually diseased parts to be sold and consumed. Finally, this parasite, like all others, would be destroyed in the process of cooking. Most authorities thus do not believe that actinomycosis in man is directly traceable to the disease in animals, but are of the opinion that both man and animals are infected from a third source, which has already been discussed above. How far these views may be modified by further and more telling investigations of the parasite fungus itself no one can predict. There are still wide gaps in our knowledge, and the presentation above simply summarizes the prevailing views, from which there are dissenters, of course. An attempt to give the views of both sides on this question would necessitate the summarizing and impartial discussion of all the experiments thus far made—a task entirely beyond the scope of the present work.
Whether an animal affected with actinomycosis should be used for human food after all diseased organs and tissues have been thoroughly removed is a question the answer to which depends on a variety of circumstances. Among these may be mentioned the thoroughness of the meat inspection itself, the extent of the disease, and the general condition of the animal affected.
The Federal meat-inspection regulations require that carcasses of animals showing generalized actinomycosis shall be condemned. If carcasses are in a well-nourished condition, showing uncomplicated localized lesions of actinomycosis, they may be passed after the infected organs or parts have been removed and condemned. When the disease of the jaw is slight, strictly localized, and without pus formation, fistulous tracts, or lymph-gland involvement, the tongue, if free from disease, may be passed. The heads affected with actinomycosis (lumpy jaw), including the tongue, shall be condemned, except that when the lesions in the jaw are strictly localized and slight in extent, the tongue may be passed, if free from disease.
ANTHRAX.
Anthrax or charbon may be defined as an infectious disease which is caused by specific bacteria, known as anthrax bacilli, and which is more or less restricted by conditions of soil and moisture to definite geographical localities. While it is chiefly limited to cattle and sheep, it may be transmitted to goats, horses, cats, and certain kinds of game. Smaller animals, such as mice, rabbits, and guinea pigs, speedily succumb to inoculation. Dogs and hogs are slightly susceptible, while fowls are practically immune. The variety of domesticated animals which it may attack renders it one of the most dreaded scourges of animal life. It may even attack man. Of this more will be stated further on.