Unvaccinated travelers who make even short-term visits to countries where typhoid fever is endemic are at risk of contracting the disease, according to an article in the July 15, 2004 issue of Clinical Infectious Diseases.
Salmonella Typhi is the typhoid fever-causing bacterium that infects people who consume contaminated food or water. Symptoms of the illness, which can be fatal if left untreated, may include fever, rash, stomachache, slowed pulse, enlarged spleen and delirium.
The study, conducted by researchers from the Centers for Disease Control and Prevention (CDC) and the University of Washington, examined nearly 1,400 typhoid fever cases reported from 1994 through 1999. Three-quarters of the cases were associated with international travel, and six countries -- India, Pakistan, Mexico, Bangladesh, the Philippines and Haiti -- were the sources of 76 percent of the travel-related typhoid fever. Only four percent of the patients had been immunized against typhoid fever within five years of traveling.
Why do so few travelers get vaccinated if the risk of illness is so high? "Many travelers probably do not seek travel advice and are unaware of the risks of typhoid fever," said Dr. Ellen Steinberg Stevenson of the CDC. She recommends that people prepare for those risks by visiting travel medicine clinics before going on international trips.
Unfortunately, one feature that people enjoy most when traveling is the one that presents the largest risk -- the cuisine. Food or water that has come into contact with human feces, whether it's shellfish that were in sewage-tinged mud or food from a street vendor with no access to a latrine or a place to wash his hands, can result in a case of typhoid fever.
Interestingly, the length of a traveler's visit wasn't the only factor influencing who got typhoid fever, since the amount of S. Typhi in a single meal could be enough to result in illness.
"You could ingest it on the first day you arrive or after being there for a few months," said Dr. Steinberg Stevenson. Of the patients studied, more than a third had spent a month or less abroad, and five percent had traveled for a week or less.
Vaccination against typhoid fever is a good way of fighting the illness, but it's not always 100 percent effective. "People should still pay attention to careful food and water practices," said Stevenson. Water-including water used for ice cubes-should be boiled before consuming. A handy CDC rule of thumb for potentially contaminated food and drink, she added, is "Boil it, cook it, peel it, or forget it."
Source: Infectious Diseases Society of America (IDSA)