Typhoid Fever Cases Linked To Foreign Travel
Infection with an antimicrobial-resistant strain of typhoid fever among patients in the United States is associated with international travel, especially to the Indian subcontinent (India, Pakistan, and Bangladesh) according to a recent study. The study also shows an increase in certain strains of typhoid fever that are resistant to the most commonly used medications for treatment.
Michael F. Lynch, M.D., M.P.H., and colleagues from the Centers for Disease Control and Prevention (CDC), Atlanta, reviewed data from 1999 to 2006 for 1,902 persons with typhoid fever who had epidemiologic information submitted to the CDC and 2,016 S Typhi isolates from public health laboratories sent to the CDC for antimicrobial susceptibility testing.
The median (midpoint) age of patients with typhoid fever was 22 years. The authors report that "1,295 (73 percent) were hospitalized and 3 (0.2 percent) died. Foreign travel within 30 days of illness was reported by 1,439 (79 percent). Only 58 travelers (5 percent) had received typhoid vaccine."
Together, three countries accounted for more than two-thirds of all travel associated cases of typhoid fever—India (47 percent), Pakistan (10 percent) and Bangladesh (10 percent). Two-thirds of these travelers reported visiting friends and relatives as the primary reason for their travel, followed by tourism (9 percent) and business travel (3 percent), which was reported much less frequently.
In addition, "272 (13 percent) of 2,016 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole (multidrug-resistant S Typhi [MDRST]); 758 (38 percent) were resistant to nalidixic acid (nalidixic acid-resistant S Typhi [NARST]) and 734 NARST isolates (97 percent) had decreased susceptibility to ciprofloxacin. The proportion of NARST increased from 19 percent in 1999 to 54 percent in 2006.