Sexually transmitted infections: recent advances.

Sexually transmitted infections are an important cause of morbidity and mortality throughout the world. Over 300 000 cases of sexually transmitted infection were diagnosed in genitourinary medicine clinics in England in 1996.[1] Among these infections, the commonest were genital warts (over 50 000 first attacks), non-specific genital infection (over 50 000 cases), proved chlamydial infection (over 30 000 cases), genital herpes (about 15000 first attacks), and gonorrhoea (over 10 000 cases).

Methods

In selecting material for this article, I used the current publications section of the journal Sexually Transmitted Infections (formerly Genitourinary Medicine) and searched Medline under the following headings: Chlamydia trachomatis, human papillomavirus, genital herpes, famciclovir, and valaciclovir.

Epidemiological changes

Rates of infection with gonorrhoea in England had been declining rapidly, even before the government launched its Health of the Nation initiative in 1992.[2] Unfortunately, soon after the target (a fall in gonorrhoea rates of at least 20% by 1995) had been reached, the trend was reversed: diagnoses of gonorrhoea in genitourinary medicine clinics rose by 20% between 1995 and 1996.[1] Over the same period, diagnoses of genital infection with C trachomatis rose by 11% and those of genital warts by 5%.[1]. Among homosexual men, there was a steady increase in the incidence of genital warts between 1990 and 1995, while there was no clear trend in the incidence of gonorrhoea (fig 1).

[Figure 1 ILLUSTRATION OMITTED]

Increasing rates of antibiotic resistant strains of gonorrhoea, such as penicillinase producing Neisseria gonorrhoeae (PPNG) and tetracycline resistant N gonorrhoeae (TRNG) (fig 2) have necessitated a switch to the use of fluoroquinolones in some areas. Reports from the United Kingdom and other countries of an increasing number of isolates of gonococcus that are resistant to fluoroquinolones, such as ciprofloxacin, are of particular concern.[4] These reports come at a time when quinolones have overtaken penicillin as the drug of first choice for gonorrhoea in genitourinary medicine clinics in the United Kingdom.[5] Reduced sensitivity to cephalosporins has also been reported and this will doubtless cause cephalosporin resistant gonococci to spread in the future.[7]

[Figure 2 ILLUSTRATION OMITTED]

Much of the gonorrhoea that is resistant to fluoroquinolones is spreading from South East Asia,[6] but some is coming from Russia.7 The former Soviet Union is also an important source of syphilis, which has shown a rapid and substantial increase in incidence there during the 1990s.[8] An epidemic of syphilis in eastern Poland has also been noted, and is said to be spreading rapidly, together with HIV, into neighbouring countries.[9] A severe outbreak of syphilis among heterosexuals in Bristol seemed to originate within the United Kingdom.[10] At the time of the published report, 27 cases had been found,[10] but further cases have since been discovered. The results of a three year survey of syphilis in pregnancy and congenital syphilis by the Communicable Disease Surveillance Centre, the British Cooperative Clinical Group (Genitourinary Medicine), and the British Paediatric Surveillance Unit should be published soon. These will confirm the need for continued vigilance.

Diagnostic methods

Amplification assays

C trachomatis infection is …