Syndromic management of sexually transmitted diseases in developing countries: what role in the control of the STD and HIV epidemics?

Abstract

The burden of sexually transmitted diseases in developing countries is enormous. The World Health Organisation (WHO) estimates that, in 1995, 333 million new cases of syphilis, gonorrhoea, chlamydial infection, and tichomoniasis occurred.' Disease burden is highest in sub-Saharan Africa, where the combined incidence of these four infections is estimated at 254 per 1000 population at risk.' Similarly, the HIV epidemic is of greatest magnitude in developing countries, it being estimated that 93% of the 27.9 million people infected with HIV by mid 1996 lived in developing countries.2 SubSaharan Africa again suffers disproportionately, comprising 68% of the people infected with HIV worldwide. These two epidemics have substantial impact. Globally, STDs collectively rank second in importance among diseases for which intervention is possible among women aged 15-44 years.3 It is projected that, in Zambia, HIV infection may increase child mortality threefold early in the next century.2 The STD and HIV epidemics are interdependent. Similar behaviours, such as frequent unprotected intercourse with different partners, place people at high risk of both infections, and it is becoming clearer that conventional STDs increase the probability of HIV transmission. Several cross sectional surveys have demonstrated a strong association between STDs and HIV infection,45 a randomised intervention study has demonstrated a substantial reduction in HIV incidence consequent upon improved STD treatment,6 and there is compelling biological evidence that STDs increase shedding of HIV and that STD treatment reduces this shedding.7 Thus, the publication of the report of an international workshop on issues around randomised trials of STD treatment for HIV prevention in this issue of Genitourinary Medicine (p 432) is particularly timely and important. The report by Hayes and his colleagues stands out as an insightful summary ofmany of the issues that surround community randomised trials and will be ofimmense interest and value to those researching STD interventions in developing countries. It discusses the important role that community randomised trials have in studying STD control strategies, outlines the different strategies that exist and that might be considered, provides a very useful section that discusses in depth some of the key epidemiological and statistical issues in the design and analysis of such trials, and closes by outlining diagnostic methods, treatment regimens, and ethical issues of relevance to such trials. Only one of the trials that is discussed has been published to date. The Mwanza (Tanzania) trial6 created a huge stir when its findings were published in 1995 and considerable hope for effective HIV prevention in developing countries