The prognosis is worse in infancy, old age and debilitated persons, and in cases of rapid collapse, low temperature and great blueness. Death rate from thirty to eighty per cent. Treatment.--Isolate the patient and disinfect all discharges and clothing. Use boiled water during an epidemic. For pain, morphine hypodermically, and apply hot applications to the abdomen. For vomiting.--Wash out the stomach and give cocaine, ice, coffee, brandy or water by the mouth. Intestines may be irrigated with a two per cent solution of tannic acid. During collapse.--Hypodermic of camphor, hot applications to the body. Good nursing and careful diet. YELLOW FEVER.--Yellow fever is an acute infectious disease characterized by jaundice, hemorrhages, albuminuria (albumin in the urine). Cause.--It is common in the West Indies and epidemic in nearby countries. It is most common in crowded, dirty, poorly drained portions of sea coast cities. It is probably caused by a specific organism which is conveyed from one person to another by mosquitoes and not in clothing, as formerly believed. One attack usually confers immunity. Symptoms.--Incubation is about three to four days. There may be a fore-warning period, but the attack is usually sudden, with chills, headache, backache, rise in fever, and general feverish symptoms, vomiting, and constipation. Early in this disease the face is flushed, while the conjunctiva and the mucous membrane lining the eyelids is congested and slightly jaundiced. Fever is 102 or 103 degrees, and falls gradually after one to three days. Pulse is slow, and while the temperature rises, it again falls. The stage of calm follows the fall of the temperature with increased jaundice and vomiting of dark altered blood, the "black vomit." Hemorrhages may also occur into the skin or mucous membranes. Brain symptoms are sometimes severe. Convalescence is usually gradual. The disease varies from great mildness to extreme malignancy. Mortality from fifteen to eighty-five per cent. [INFECTIOUS DISEASES 225] Treatment.--Prevent spread of the infectious mosquitoes; use screens and netting in infected districts. Careful nursing, food by rectum while vomiting is frequent. For the hemorrhage opium is given; frequent bathing will keep down the fever; and for the vomiting cocaine is given and cracked ice.