Safety and immunogenicity of different immunization regimens of CVD 103-HgR live oral cholera vaccine in soldiers and civilians in Thailand.

Attenuated Vibrio cholerae oral vaccine CVD 103-HgR was well tolerated by 324 Thai soldiers and civilians. Most received a single 5 x 10(8) cfu dose, while 40 each received one or two 5 x 10(9) cfu doses. Vibriocidal antibody (the best correlate of immunity) seroconversion was lower in soldiers than civilians (P less than .001). Increasing the vaccine dose to 5 x 10(9) cfu raised the geometric mean titer (P less than .001). A second 5 x 10(9) cfu dose one week later did not notably increase seroconversions. Likelihood of seroconversion was inversely correlated with baseline vibriocidal titer (P less than .001). CVD 103-HgR caused seroconversion in most subjects with baseline titers less than or equal to 1:40, including 100% of civilians after one 5 x 10(8) cfu dose, 79% of soldiers after one 5 x 10(9) cfu dose, and 45% of soldiers after one 5 x 10(8) cfu dose. In persons with elevated baseline titers, vibriocidal antibody seroconversion is not a sensitive measure of whether vaccine has boosted intestinal immunity; for such subjects, other measurements must be used. Study regimens in endemic areas should use a single 5 x 10(9) cfu dose.

Etiology of urethritis in Thai men.

The etiology of urethritis was determined for 303 Thai men with urethral discharge containing 5 or more polymorphonuclear cells (PMN)/high power field (hpf) and 132 men with a discharge containing less than 5 PMN/hpf. Neisseria gonorrhoeae was isolated significantly more often from men with greater than or equal to 5 PMN/hpf than from men with less than 5 PMN/hpf (42% vs 1%, P less than .0001). Chlamydia trachomatis was also isolated more often from patients with greater than or equal to 5 PMN/hpf than from men with less than 5 PMN/hpf (16% vs 8%, P less than .03). Ureaplasma urealyticum was isolated with nearly equal frequency from both groups of patients (45% vs 37%). Among men with a urethral exudate containing greater than or equal to 5 PMN/hpf, N. gonorrhoeae was isolated as the only pathogen from 19% and in combination with C. trachomatis or U. urealyticum in 23% of these men. C. trachomatis or U. urealyticum, but not N. gonorrhoeae, was isolated from 30%, and no pathogen was isolated from 28% of these men. Among men with urethral exudate containing less than 5 PMN/hpf, N. gonorrhoeae was isolated from only 1%, C. trachomatis or U. urealyticum from 41%, and no pathogen from 58%. These findings suggest that all Thai men with urethral discharge containing greater than or equal to 5 PMN/hpf should be treated for non-gonococcal urethritis and for gonococcal urethritis if gram-negative diplococci are demonstrated on gram stain of the urethral discharge. Men with urethritis with less than 5 PMN/hpf should be treated for only non-gonococcal urethritis.

Evaluation of 500- and 1,000-mg doses of ciprofloxacin for the treatment of chancroid.

A randomized, double-blind study was performed comparing ciprofloxacin in a 500-mg single dose with 1,000 mg (500-mg doses given 12 h apart) for the treatment of chancroid in Thailand. Haemophilus ducreyi was isolated from 87 (48%) of 180 men with a clinical diagnosis of chancroid. For men with ulcers that were culture positive for H. ducreyi, rates of cure were 100% in the 500-mg group and 98% in the 1,000-mg group. For men with ulcers that were culture negative for H. ducreyi, rates of cure were 93% in the 500-mg group and 96% in the 1,000-mg group. The MIC of ciprofloxacin for 50% of isolates among 85 isolates of H. ducreyi was 0.007 micrograms/ml (range, 0.002 to 0.03 micrograms/ml). No significant adverse effects were detected in either group. These data indicate that both of these treatment regimens are equally effective therapies for chancroid in Thailand.

Clinical and microbiological efficacy of a single dose of norfloxacin in the treatment of chancroid.

Forty-one men with a clinically and bacteriologically verified diagnosis of chancroid were given a single dose of 800 mg of norfloxacin and were examined clinically and bacteriologically four, seven and 14 days after treatment. Five patients were excluded from evaluation of efficacy due to concomitant infections or incomplete follow-up. Of the remaining 36 patients, 34 were cured and culture negative at follow-up controls. Another 15 men with culture-negative ulcers treated with 800 mg of norfloxacin as a single dose, were all cured clinically. The high cure rate and the good tolerability make norfloxacin a convenient and cheap alternative to intramuscular single dose therapy of chancroid.