Disease prevention by the developement of an active arti ficial immunization against the infective agent concerned, among all susceptibles in a given population, is our chief weapon in the control of certain infections such as small pox, and a valuable adjunct in others. The maximum effi ciency of such measures is only achieved where immunization is made compulsory and where furthermore, the requirement is enforced, so that a large part if not all the people are pro tected Unfortunately in civil life, compulsory vaccination has lead to a greater or less amount of opposition among a few bigoted persons who fortify their position by refering to the very small number of accidents and secondary infections fol lowing the practice, and ignore the achievements in disease reduction that has followed the extensive employment of the method. This opposition in some localities has been so vigo rous that authorities have been unable to enforce the provisions of laws requiring compulsory vaccination while in others the authorities are forced into a continuous fight to prevent the repeal of the statutory requirements. In many localities the
situation is discouraging. Fortunately the situation has a redeeming feature. Those who receive immunization receive protection, while those who do not, either through ignorance, carelessness or opposition run the far greater hazard of the virulent infection. Those who remain unvaccinated through opposition are sufficiently punished if they contact infection. Health authorities can in a large measure protect the individuals of the other groups by education of the public in the advan tages of vaccination, by the distribution of free vaccine, and by providing for its free administration. Sufficient activity along these lines may very nearly achieve the same results as compulsory methods, without arousing hampering opposition. Practicing physicians can do a great deal in disease prevention by actively immunizing their clientel.