Typhoid Fever

Introduction

Typhoid Fever (TF) is a disease caused by Salmonella Enterica Typhi which is an intestinal bacteria. Human to human transmission occurs with the ingestion of food/water that has been contaminated by the fecal material of an infected person. Approximately 3-5% of persons infected will become chronic (versus acute) carriers of the disease. This means they may show no overt symptoms but continue to shed the bacteria and transmit TF to others.

Typhoid Fever is most prevalent in the developing areas of India, Asia, Africa, Central/South Americas and the Caribbean. Industrialized nations are not at risk because of the quality of their sanitation practices. Most cases of TF reported in industrialized areas are travelers who have returned from a developing country.^[1][2]

Prevention

• Typhoid Fever immunization*
• If you drink water, buy it bottled or bring it to a rolling boil for 1 minute before you drink it. Bottled carbonated water is safer than uncarbonated water. (The TF bacterium requires oxygen to survive. Carbonated water is infused with carbon dioxide which creates the "bubbles" and, in turn, decreases the amount of oxygen available for the bacteria's survival.)
• Ask for drinks without ice unless the ice is made from bottled or boiled water. Avoid popsicles and flavored ices that may have been made with contaminated water.
• Eat foods that have been thoroughly cooked and that are still hot and steaming.
• Avoid raw vegetables and fruits that cannot be peeled. Vegetables like lettuce are easily contaminated and are very hard to wash well.
• When you eat raw fruit or vegetables that can be peeled, peel them yourself. (Wash your hands with soap first.) Do not eat the peelings.
• Avoid foods and beverages from street vendors. It is difficult for food to be kept clean on the street, and many travelers get sick from food purchased from street vendors.^[1]

Pre-Exposure Vaccinations

Two types of vaccine are available around the world.

• The first is an injectable which is administered at least 1 (preferably 2) week(s) prior to travel and is effective up to 2 years in duration. A booster (at 2 years) is recommended for those planning to re-enter risk areas. The injectable vaccine can be given to children starting at 3 years of age.
• The second is an oral vaccine in capsule form. A series of 4 capsules are taken in total, with the last capsule being administered at least 1 week prior to travel. The dosing is one capsule on days 0, 2, 4, & 6 (every other day). A booster is recommended every 5 years for those planning to re-enter a risk area. The oral vaccine can be administered to children starting at 6 years of age. Capsules must be kept refrigerated, not frozen, to maintain their potency. They should not be taken with water warmer than 37C/98.6F degrees as higher temperatures can inactivate the vaccine's components.^[1]

*It must be noted that the vaccines (both oral and injectable) do not produce 100% immunity to TF. They do, however, produce a 50-80% effectiveness rate which greatly increases the survival of those infected.^[2] Receiving the pre-exposure inoculations can also lessen the severity and duration of the infection.

Symptoms and Treatment

Symptoms

Typhoid Fever has an incubation period of 1-2 weeks post-exposure.
Most patients will experience decreased appetite, headache, generalized achiness, lethargy and sustained high fevers (39-40C/103-104F). These are often accompanied by abdominal pain, chest congestion and a rose-colored skin rash. Some patients will experience relapses of high fever. This is especially true in patients who have received antibiotic treatment. Laboratory analysis of stool and/or blood samples are required for accurate diagnosis.^[1][3]

Treatment

The treatment for Typhoid Fever is administration of one or more antibiotics. Hospitalization may or may not be required depending on the severity of symptoms. The disease has a duration of 4-6 weeks. In some areas, the bacteria has become resistant to particular antibiotics so treatment will be area-dependent.

Symptoms will subside before the end of the treatment period. If you are being treated on an out-patient basis, certain precautions should be followed to prevent the spread of the disease to others.^[1]

• Finish all prescribed medications.
• Wash hands thoroughly with soap and water after every bathroom visit.
• Do not prepare/serve food for other people.
• Have stool cultures performed regularly during treatment/recovery for the presence/non-presence of the bacteria in your system.