The epidemic potential is serious in louseinfested populations. Epidemics may be expected in wars, famines, and other conditions, where people are overcrowded and malnourished. Poor personal hygiene encourages pediculosis. During epidemics, all contacts and perhaps the entire community should be deloused with a residual insecticide. Administer the vaccine to susceptible persons, if directed.
Immunization is not required for international travel.
An attack of yellow fever usually results in abrupt signs and symptoms of fever, headache, backache, nausea, vomiting and prostration. Later in the course of the disease, the heart rate slows and becomes weaker, and there is a decreased output of urine. Bleeding may occur from the nose, mouth, and stomach. The stools become dark colored and tarry due to the presence of blood. Jaundice is mild early in the disease and becomes pronounced later. The mortality rate may be very high.
Urban yellow fever (transmitted by the Aedes aegypti mosquito) has not occurred in the Americas since 1954. However, outbreaks of urban yellow fever are now reported from other countries/continents. Jungle yellow fever is found in several African countries and in Central and South America.
The infectious agent is the yellow fever virus. Man and the Aedes aegypti mosquito are the reservoirs for urban yellow fever. The reservoirs for jungle fever are monkeys, marsupials, and forest mosquitoes. Man acquires the disease when bitten by an infected mosquito. The incubation period is from 3 to 6 days. Patients with yellow fever are infective from just prior to the onset of fever through the first 3 to 5 days of the illness. When infected, mosquitoes remain so for life.
There is no treatment other than supportive measures.
Preventive measures against urban yellow fever are primarily through eradication of the Aedes aegypti mosquitoes. Vaccination for humans is also indicated. Jungle yellow fever can be controlled best by immunizing all persons who work or visit endemic areas. Any person who enters these areas should use protective clothing, repellents, and bed nets.
Management of patients, contacts, and the nearby environment includes patient blood isolation precautions. In rural areas, deny mosquitoes access to patients for at least 5 days after the onset by screening, spraying with residual insecticides, and using bed nets. Insecticides should be applied in all houses in the area.
As part of the investigation, question the patient about all places visited 3 to 6 days prior to the onset to determine where yellow fever was acquired (focus), and place all persons visiting the focus under surveillance. Survey suspected areas for mosquitoes that transmit the disease and eradicate them with approved insecticides, if possible. Investigate deaths and mild illnesses with fever in the area to determine if yellow fever was involved.
International measures require that ships, aircraft, and land transportation arriving from areas where yellow fever is endemic will follow regulation outlined in International Health Regulations. Many countries require a valid international certificate of yellow fever vaccination when traveling through or from yellow fever areas. The certificate is valid from 10 days after vaccination through the next 10 years.
As a Medical Department representative, you will often be called upon to help ensure that all hands have healthful living conditions, both ashore and afloat. This manual gives only a rough outline of your responsibilities. To perform adequately in this area, you must become familiar with the BUMED/NAVMEDCOM Instructions in the 6200 series, the Manual of Naval Preventive Medicine (NAVMED P-5010), and other applicable manuals and publications that may be referenced or become available to you.
Foodborne illnesses are an ever-present danger in the military environment. They pose a real threat to the health and morale of our personnel. To prevent their occurrence, one must ensure that all foods are procured from approved sources and processed, prepared, and served with careful adherence to recommended sanitary practices. The majority of foodborne illnesses can be traced to food that has been prepared too far in advance; inadequate refrigeration; disregard for temperature and time factors; or food service personnel who ignored or are inadequately trained in food handling techniques. These points need to