(introduction...)

The Whole Strategy

Hologram 4: The Detailed Description

The control of sexually transmitted diseases (STDs) is an essential component of all public health programs. Controlling STDs is important because they not only cause great morbidity but as studies have shown, left uncontrolled, they significantly increase the spread of HIV. Developing country health providers at all levels, in both the public and private sectors, are confronted with many patients with STDs. In some countries, STD-related complaints are among the most common reasons why adults seek health care. However, primary health care facilities in developing countries and other resource-poor settings face several constraints in the management of patients with STDs. These constraints include lack of access to the laboratory technology necessary for making etiologic diagnoses of STDs, shortages of well-trained staff, high workloads and limited staff time available per patient. Thus, in resource-poor settings the appropriate STD management tool should enable health care workers to make a correct diagnosis in most patients within a short time and without sophisticated laboratory tests, specialized skills, or, preferably, the need for a repeat visit by the patient.

STDs have devastating health effects, especially for women. STDs, such as gonorrhea and chlamydia, are important factors that cause pelvic inflammatory disease (PID), chronic pelvic pain, ectopic pregnancies, sterility, pre-term deliveries and, along with syphilis, poor birth outcomes. Venereal warts have been linked with cervical cancer. If a mother is infected with an STD, such as syphilis, gonorrhea, chlamydia, or hepatitis B, at the time of birth, she may transmit the infection to the child. Some of the effects of these infections on a newborn are conjunctivitis, pneumonia, crippling bone and teeth disorders, and liver disease.

There are many components of a successful STD control program. These include prevention programs to reduce high risk behaviors, promote increased and correct use of condoms, improve screening of asymptomatic populations looking for undetected disease, and aggressively pursue treatment for sexual partners of index cases. However, comprehensive case management of STDs is the cornerstone of STD control. Prompt and effective case detection and treatment result in immediate health benefits for individual patients. Furthermore, reducing the duration of patients' infectiousness decreases the incidence and prevalence of STD in the population. In addition, it is possible to detect and treat asymptomatic STDs by identifying the sexual contacts of STD patients.

This booklet begins with an overview of the burden of HIV and STD on countries and the role of STD on HIV transmission. The syndromic management of STDs is then presented, including its advantages, disadvantages and cost-effectiveness. The design of STD flowcharts follows, with specific examples of flowcharts provided for urethral discharge syndrome in men, vaginal discharge syndrome in women, pelvic inflammatory disease and genital ulcer disease. Other components of comprehensive STD case management are also examined, such as partner treatment, health education, training, and syphilis screening and treatment. The application of STD syndromic management specifically in Latin America and the Caribbean is presented, highlighting the AIDSCAP priority countries of Haiti, Jamaica, Brazil, Honduras and the Dominican Republic. Finally, major lessons learned are discussed, and the booklet concludes with recommended steps to implement the syndromic approach to improve client-centered STD service delivery.

HIV and STD Global Burden

HIV infection is not distributed equally around the world. It is estimated that there are over 20 million people living with HIV infection worldwide. Approximately 68 percent of these individuals are in Sub-Saharan Africa, where the prevalence among sexually active adults has reached one third in some urban centers. Ten percent of people living with HIV infection are in Latin America and the Caribbean, although the prevalences vary widely throughout the region. Southeast Asia represents 7.5 percent of the total HIV infections, although that rate is rapidly rising. Similarly, 7.5 percent of HIV infections originate in North America, although the epidemic has stabilized in this region as it has in Europe where 6 percent of all infections reside.⁶

In the Latin America and Caribbean region, Haiti was the first country to be affected by HIV. Based on in-country data collected in the region between 1994 and 1996, the HIV prevalence among Haitian adults is 10 percent in urban areas and 4 percent in rural areas. Brazil accounted for the largest number of reported AIDS cases in the region due to its huge population and an estimated .4 percent prevalence in the sexually active adult population, with higher rates among high risk individuals. Among STD clinic attendees in Rio de Janeiro, men had an HIV prevalence of 18 percent and women 5 percent. In Jamaica, the HIV prevalence among adults was similar to that of Brazil, .4 percent. STD clinic attendees in urban Jamaica had an HIV prevalence of 4 percent. In the Dominican Republic, HIV prevalence among ante-natal women ranged from 1 to 2 percent but was as high as 8 percent in one urban area. The prevalence among STD clinic attendees varied from 1.5 percent among men or women presenting with either a urethral discharge or vaginal discharge, to 16.7 percent among patients presenting with genital ulcers. In Honduras, the prevalence of HIV among pregnant women in urban areas was 2 to 4 percent.

The worldwide burden of STDs is staggering. The World Health Organization estimates that between 150 and 330 million new cases of curable STDs are transmitted each year. These curable STDs include gonorrhea, chlamydial infection, trichomoniasis, syphilis, and chancroid. Between 40 and 50 percent of these STD cases occur in Southeast Asia, between 20 and 25 percent in sub-Saharan Africa, 10 to 11 percent in Latin America and the Caribbean, 5 to 6 percent from Northern Asia and Eastern Europe, and 1 to 2 percent in North America.⁶

In Latin America and the Caribbean, the STD prevalence rates and completeness of STD reporting vary from country to country. Between 1993 and 1997, STD prevalence rates were examined in the region. In Brazil, the prevalence of either chlamydia or gonorrhea among asymptomatic women or women presenting with vaginal discharge was similar, between 12 and 14 percent. In the general population of adults, the syphilis serology rate was 1 percent, but among STD clinic attendees it was 8 to 11 percent. Three to six percent of both men and women clinic attendees presented with genital ulcers. In the Dominican Republic, among women complaining of vaginal discharge, 8 percent were infected with either gonorrhea or chlamydia and 3 percent had positive syphilis serologies. Among men with symptoms of urethral discharge, 36 percent had gonorrhea and 29 percent had chlamydial infections. Of those men with genital ulcers, 37 percent had herpes, 16 percent had chancroid and 16 percent had syphilis. In Jamaica, symptomatic women had a chlamydial or gonococcal infection rate of 34 percent, and asymptomatic women had a chlamydial or gonococcal prevalence of 15 percent. Approximately 6 percent of STD clinic attendees presented with genital ulcers. Of these, 44 percent had genital herpes, 19 percent had chancroid and 10 percent had syphilis. In Haiti, 12 percent of asymptomatic women had either gonorrhea or chlamydia, and 35 percent were infected with trichomoniasis. Eleven percent had positive syphilis serologies. In Honduras, the actual prevalence of STDs is unknown, but reported cases show a population-based rate of gonorrhea at .04 percent and .06 percent for syphilis. Probably a better marker for syphilis prevalence is the .32 percent of pregnant women who had positive syphilis serologies.

Role of STD on HIV Transmission

Although the probability of HIV infection through sexual contact varies greatly, it appears to be lower than that of infection through other routes of exposure (see Figure 1).⁷ The variability among and within routes of HIV exposure depends partly on the viral dose and also on whether the virus is transmitted directly into the blood or onto a mucous membrane.

Figure 1 - Per Contact Probability of HIV Transmission

HIV infectivity is the average probability of transmission to another person after that person is exposed to an infected host. Infectivity plus two other parameters — the duration of infectiousness and the average rate at which susceptible people change sexual partners — determines whether the epidemic grows or slows. On a population level, all three corners of the classic epidemiologic triangle — susceptibility and infectiousness, the social, cultural and political milieu, and HIV type — determine HIV infectivity.

The development of syndromic management guidelines and other efforts to improve STD management and prevention at "points of first encounter" with the health system were prompted by the rapid spread of the HIV/AIDS epidemic. One reason for this new attention to STDs is obvious: the sexual behaviors that lead to STDs also promote the spread of HIV. However, early in the HIV/AIDS epidemic, results of epidemiological and laboratory research suggested STDs actually enhance HIV transmission, both infectiousness and susceptibility. Given this evidence of a link between HIV and other STDs, the AIDSCAP project of Family Health International made improving STD prevention and treatment one of its main HIV prevention strategies when the project began in 1991.

Critical to the development of optimal strategies for HIV control is understanding the role of other STDs in the transmission of HIV, the role of STDs in the progression of HIV disease, and the role of HIV infection in alterations of natural history, diagnosis, or response to therapy of STDs. Of 75 studies conducted on the role of STDs in HIV transmission, 15 analyses of clinical examinations or laboratory evidence of STDs, adjusted for sexual behavior, showed that both STDs that cause genital ulcers and non-ulcerative STDs, such as gonorrhea and chlamydia, increase the risk of HIV transmission approximately three- to ten-fold. Preliminary data from 83 reports on the impact of HIV infection on STDs suggest that, at a community level, HIV infection may increase the prevalence of some STDs (e.g., genital ulcers). If co-infection with HIV prolongs or augments the infectiousness of individuals with STDs, and if the same STDs facilitate transmission of HIV, these infections may greatly amplify one another. This "epidemiological synergy" may be responsible for the explosive growth of the HIV pandemic in some populations.⁸

The results of several important studies have confirmed the validity of the HIV prevention strategy to improve STD prevention strategy to improve STD prevention and treatment. In a landmark pilot study in Mwanza, Tanzania,⁹ use of the syndromic approach to STD treatment that AIDSCAP and the WHO had advocated worldwide reduced HIV incidence by 42 percent. The objectives of the community-based randomized intervention trial were to establish a program based on syndromic management for the improved diagnosis and treatment of STDs in the general population, and to measure the impact of this intervention on the incidence of HIV infection and on the prevalence and incidence of STDs. The improved STD services, which decreased HIV incidence by 42 percent over a 2 year period, were designed to be feasible rather than optimal, were integrated with the Tanzanian primary-health-care system, and were based on syndromic treatment algorithms as recommended by WHO.¹⁰

Because this observed reduction occurred in both sexes, and was observed consistently in all matched pairs of study communities, and in the absence of sexual behavior change, the most plausible explanation for these results is that the STD treatment program reduced HIV incidence by shortening the average duration of STDs, thus effectively reducing the probability of HIV transmission.

Recent research in Malawi¹¹ and Cote d'lvoire¹² produced strong biological and epidemiological evidence that STDs are associated with higher HIV infection rates and that STD treatment can make HIV-positive men less infectious. In the Malawi study, HIV-1 seropositive men with urethritis had HIV-1 RNA concentrations in seminal plasma eight times higher than those in seropositive men without urethritis. After the urethritis patients received antimicrobial therapy directed against STDs based on syndromic management, the concentration of HIV-1 RNA in semen decreased significantly. These results suggest that urethritis increases the infectiousness of men with HIV-1 infection and that this infectiousness can be reduced with prompt and effective treatment.

And finally, in a large epidemiologic study conducted in Cote d'lvoire,¹² among more than 1,000 sex workers, the rate of HIV was between 2 and 5 times greater in those women who had at least 1 STD (gonorrhea, chlamydia, trichomoniasis, syphilis, chancroid) compared to those women who had no STDs found.