Typhoid Fever

Typhoid fever, a serious intestinal infection, is now uncommon in the United States, with only about 500 cases a year, but it continues to thrive in areas lacking proper sanitation. The disease is caused by the Salmonella typhi bacterium and is considered the prototype of salmonella infections.

Infection is caused by ingesting food or water contaminated by the S. typhi organism, which is shed in the feces and urine of typhoid carriers, some of whom may be asymptomatic. Initially, the bacteria multiply in the small intestine for 24 to 72 hours before entering the bloodstream. Most are destroyed by the body's immune system, but those that survive continue to multiply. The surviving bacteria commonly infect the gallbladder and bile ducts; from there, they are able to return to the intestinal tract by way of the bile, allowing for reinfection.

As S. typhi bacteria enter the bloodstream, the person may develop fever, chills, generalized aches in the muscles and joints, abdominal pain, and a rose-colored rash. Unlike other salmonella infections, diarrhea and vomiting are minimal or absent.

The course of typhoid fever is unpredictable hi some mild cases, it is self-limiting. In others, fever disappears, only to return one or two weeks later. In still others, life-threatening complications, such as intestinal bleeding and perforation, pneumonia, and hepatitis develop.

Some people become asymptomatic typhoid carriers without knowing it. There are an estimated 2,000 such persons in the United States. In most of these individuals, S. typhi is harbored in the gallbladder. For unknown reasons, most carriers are women over the age of 50. When carriers are identified, they must be reported to local health authorities and are prohibited from handling commercially served food.

Most Americans who contract typhoid fever do so during travel to Mexico, India, and other countries where the disease is endemic. Cases in the United States are usually traced to food handled by an asymptomatic carrier, although there have been instances of typhoid fever contracted by eating oysters and other shellfish from polluted waters.

Diagnostic Studies and Procedures

Diagnosis is based on the isolation of S. typhi organism from the blood, stools, or other tissues of an infected person.

Medical Treatments

Untreated typhoid fever has a mortality rate of more than 10 percent, but antibiotic therapy can cut this to less than 2 percent. In the past, chloramphenical was the drug of first choice, but in some parts of the world, S. typhi has developed resistance to this drug as well as to ampicillin. If chloramphenicol does not work, newer cephalosporin antibiotics, such as ceftriaxone (Rocephin) or cefoperazone (Cefobid), are given intravenously twice a day for one to two weeks. Other drugs that may be used include furazolidone (Furoxdne), ciprofloxacin (Cipro), ofloxacin (Floxin), and trimedtoprim with sulfamethoxazole (Bactrim or Septra).

Asymptomatic carriers are also treated with antibiotics. Typical regimens include trimethoprim with sulfamethoxazole or rifampin (Rimactane or Rifadin). To make sure the S. typhi organism has been destroyed, a series of three negative stool tests, taken at weekly intervals, are needed.

In individuals with gallbladder disease, its removal is often necessary to eradicate the S. typhi. Intestinal perforation usually requires emergency surgery. Transfusions are sometimes needed if there is hemorrhaging or chronic intestinal bleeding.

Alternative Therapies

Nutrition Therapy. Recovery may be faster with a suitable high-calorie, high-protein diet to restore energy and normal weight. Frequent, small meals are recommended. If diarrhea occurs, a clear liquid diet or intravenous fluids and feeding might be necessary. Iron supplements are needed if intestinal bleeding has caused anemia.

Self-Treatment

Bed rest is advisable, especially when there is a fever and other symptoms. Aspirin should be avoided because it increases the risk of intestinal bleeding and other complications. Laxatives and enemas pose similar dangers.

Anyone who has had typhoid fever can continue to shed the S. typhi organisms for up to six months, even after antibiotic treatment. Thus, they should not handle food served to others until stool tests are negative Thorough hand washing and meticulous attention to personal hygiene can help protect others from contracting the disease.

Immunization is advised for travelers to underdeveloped areas, laboratory workers, and others at high risk for exposure to typhoid fever. Because it is not 100 percent effective, immunized persons should be cautious about food and water in areas where typhoid is endemic.

Other Causes of Typhoid Symptoms

Some other salmonella infections can produce fever, prostration, and other symptoms similar to those of typhoid.