=Detection.=--Smallpox is often mistaken for chickenpox, or some of the skin diseases, in its mild forms. The reader is referred to the article on chickenpox for a consideration of this matter. The mild type should be treated just as rigidly as severe cases with regard to isolation and quarantine, being more dangerous to the community because lightly judged and not stimulating to the adoption of necessary precautions. The preliminary fever and other symptoms peculiar to smallpox will generally serve to determine the true nature of the disease, since these do not occur in simple eruptions on the skin. The general symptoms and course of smallpox must guide the layman rather than the appearance of the eruption, which requires educated skill and experience to recognize. Chickenpox in an adult is less common than in children. Smallpox is very rare in one who has suffered from a previous attack of the disease or in one who has been successfully vaccinated within a few years. =Outlook.=--The death rate of smallpox in those who have been previously vaccinated at a comparatively recent date, or in varioloid, as it is called when thus modified by vaccination, is only 1.2 per cent. There are, however, severe cases following vaccinations done many years previous to the attack of smallpox. While these cannot be called varioloid, yet the death rate is much lower than in smallpox occurring in the unvaccinated. Thus, before the mild epidemic of 1894 the death rate in the vaccinated was sixteen per cent; since 1894 it has been only seven per cent; while in the unvaccinated before 1894 it was fifty-eight per cent; and since that date it has been but seventeen per cent, as reported by Welch from the statistics of 5,000 cases in the Philadelphia Municipal Hospital. =Complications.=--While a variety of disorders may follow in the course of smallpox, complications are not very frequent in even severe cases. Inflammation of the eyelids is very common, however, and also boils in the later stages. Delirium and convulsions in children are also frequent, as well as diarrhea; but these may almost be regarded as natural accompaniments of the disease. Among the less common complications are: laryngitis, pneumonia, diseases of the heart, insanity, paralysis, various skin eruptions, inflammation of the joints and of the eyes and ears, and baldness. =Treatment.=--Prevention is of greatest importance. Vaccination stands alone as the most effective preventive measure in smallpox, and as such has no rival in the whole domain of medicine. The modern method includes the inoculation of a human being with matter taken from one of the eruptive points on the body of a calf suffering with cowpox. Whether cowpox is a modified form of smallpox or a distinct disease is unknown.