Asymptomatic carriage of Haemophilus ducreyi confirmed by the polymerase chain reaction

To investigate asymptomatic carriage of Haemophilus ducreyi by using polymerase chain reaction (PCR) on samples from women at high risk of infection.

213 commercial sex workers (CSWs) recruited in The Gambia, West Africa.

Genital samples (cervical, vaginal and ulcer) were tested for the presence of H ducreyi by PCR with the technique of "one tube nested primer".

12 CSWs were PCR positive for H ducreyi; 8 of these women had genital ulcers on examination.

Using a simplified PCR technique for detecting H ducreyi we have shown that 2% of CSWs were carrying the organism without clinical symptoms or signs. This has important implications for sexually transmitted disease control programmes in areas with a high prevalence of chancroid.