Clinical Features

• The classical sign of typhoid is fever. Fever is continuous and increases as the disease progresses.
• A few patients may show abdominal discomfort associated with diarrhea.
• Non–specific symptoms: Chills, sweating, headache, loss of appetite, weakness, sore throat, dry cough, constipation and muscle pains are often present.
• Patients may lose interest in their surroundings.

Physical examination

• Abdomen: On examination, the abdomen shows tenderness associated with enlarged spleen and liver.
• Rosy spots may appear on the lower chest and upper abdomen. These may appear in the second week.
• The pulse rate is generally slow (relative bradycardia).

Treatment and Prevention of Typhoid Fever
The carrier should be given an intensive course of ampicillin (4–6g a day) together with probenecid for about six weeks.
Control of sanitation
Protection and purification of drinking water supplies, improvement of basic sanitation, and promotion of food hygiene are essential measures to interrupt transmission of typhoid fever. When sanitation is combined with health education, the effects tend to be cumulative, resulting in a steady reduction of typhoid morbidity.

Immunization
Immunization against typhoid does not provide 100% protection, but it definitely lowers both the incidence and seriousness of the infection. it can be given at any age upwards of one year. It is recommended for:

1. Those living in endemic areas.
2. Household contact.
3. Groups at a risk of infection such as school children and hospital staff.
4. Travelers proceeding to endemic areas.
5. Those attending melas and arts.

Anti typhoid vaccine
The anti–typhoid vaccines currently available in India are the infectable ones:

1. Monovalent anti–typhoid vaccine.
2. Bivalent anti–typhoid vaccine.
3. TAB vaccine.

Dosage and mode of administration
Primary immunization should consist of two doses (each of 0.5ml) of the vaccine, given subcutaneously, at an interval of about four to six weeks. Children between one and 10 years are to be given smaller doses (i.e. 0.25ml).

Reactions
The typhoid vaccine generally causes local reactions (pain, swelling and tenderness), and also very frequently, constitutional symptoms such as malaise, headache, and pyrexia, which however, usually subside within 36 hours. To reduce the severity of reactions, it has been advised that the vaccine be administered late in the afternoon or evening. Aspirin or other anti–pyretic drugs may be administered to mitigate the unpleasant reactions. Women should not be injected during late pregnancy.

Storage
Anti–typhoid vaccines should be stored in a refrigerator at 20 to 40°C. They should not be frozen.