CONTAGION. Before the time when the microscope and other laboratory aids showed the actual causes of many disease processes in the human — and other animals — body, the word contagion was surrounded by much mys tery. At the present time the term "com municable" is preferable. Thus communicable diseases are those which result from actual or remote contact with the host. There arc a great many such communicable diseases. The actual contagium or causative factor is known for many, while for others it has yet to be definitely determined. In many instances where the actual contagium is known, the method of the transmission is still in doubt. Thus in the group of exanthematous diseases such as measles, scarlet fever, smallpox, chickenpox, the actual contagion has not been demonstrated. For diphtheria, whooping cough, boils, carbuncles, tuberculosis, typhoid fever, cerebrospinal menin gitis, plague, cholera, pneumonia, erysipelas and influenza the actual causative agents are minute plants belonging to the group of bacteria. The contagium of syphilis, sleeping sickness, yaws, Aleppo boil and a group of related diseases are minute animalcule of the protozoa group. The contacts here are direct; while malaria, which is also a communicable disease, is caused by a minute animal form of the protozoa group, which is usually transmitted by an intermediary host, such as the mosquito. Thus in malaria the process is as follows: The minute animal form causing it is found in the blood and other tissues of the sick individual. This is taken into the body of a biting mosquito. usually of a special type, Anopheles; for the common chills and fever of the United States, the malarial parasite undergoes a series of changes in its mosquito host and then is carried to a well individual through the bite of an infected mosquito. In former years much non sense was talked and taught by physicians about miasmas, and dangerous night air, and the harmfulness of dampness, etc. The dangers existed, not in a hypothetical minas, but in real mosquitoes that usually flew and fed about dusk and which lived in wet, springy localities If there were no patients with the parasite, there would be no malarial plasmodia to be communicated. Hence malaria is stamped out either by getting rid of mosquitoes or isolating, patients and preventing the mosquitoes from carrying away blood with the real cause.
Many communicable diseases are• borne by the air and involve the respiratory tract. In fluenza and pneumonia are among these. In epidemics breathing masks worn by the. sick may prevent spread of contagions. Typhoid fever and cholera are usually communicated by means of the digestive canal. They are best eradicated by proper sanitation. They are pre ventable. A community which has much typhoid fever is deficient in social intelligence. Such a community prefers corrupt politics to dean water supplies and deserves what it gets, the death of its young people. High per centages of typhoid in communities is in direct proportion to the social enlightenment of the same communities.
In general it may be said that so-called dis infectants, etc., which are used to prevent com municable diseases are a relic of the dark ages. ((Cleanliness is next to godliness)) is a good maxim, but should apply to spiritual cleanliness as well. The fight against gonorrhea and syphilis is a losing one. The moral tone of the race is still too infantile to stamp these scourges out in the community as yet. Certain restrictive measures are of some service, but a higher degree of sexual intelligence is needed to combat these two prevalent communicable diseases. So long as knowledge of the most important function of the human race is con sidered improper, so long will gonorrhea and syphilis be widespread. When the community realizes that sex knowledge is the most import ant kind of knowledge to have, then that com munity will gain the ascendancy over the so called venereal diseases, and those individuals who have grown away from their infantile sexuality will live.
There is a whole group of communicable diseases due to contagions from animals. Such are tape worm, hook worm, round worms, etc. Here the ova, or eggs, pass from the animal direct, through handling dirty animals, dogs particularly, or the fecal matter containing the ova is conveyed through water supplies, or through food contaminated by infected water. The old distinctions between contagion and in fection are no longer tenable, hence the terms are used interchangeably, or better, supplanted by the term communicable.
Shunt ELY JELLIFFE.