The transformation of partner notification

Sustained high HIV case-finding through index testing and partner notification services: experiences from three provinces in Zimbabwe

INTRODUCTION

Several countries in southern Africa have made significant progress towards reaching the Joint United Nations Programme on HIV/AIDS goal of ensuring that 90% of people living with HIV are aware of their status. In Zimbabwe, progress towards this "first 90" was estimated at 73% in 2016. To reach the remaining people living with HIV who have undiagnosed infection, the Zimbabwe Ministry of Health and Child Care has been promoting index testing and partner notification services (PNS). We describe the implementation of index testing and PNS under the Zimbabwe HIV Care and Treatment (ZHCT) project and the resulting uptake, HIV positivity rate and links to HIV treatment.

METHODS

The ZHCT project has been implemented since March 2016, covering a total of 12 districts in three provinces. To assess the project's performance on index testing, we extracted data on HIV testing from the district health information system (DHIS 2) from March 2016 to May 2018, validated it using service registers and calculated monthly HIV positivity rates using Microsoft Excel. Data were disaggregated by district, province, sex and service delivery point. We used SPSS to assess for statistical differences in paired monthly HIV positivity rates by sex, testing site, and province.

RESULTS

The average HIV positivity rate rose from 10% during the first six months of implementation to more than 30% by August 2016 and was sustained above 30% through May 2018. The overall facility HIV positivity rate was 4.1% during the same period. The high HIV positivity rate was achieved for both males and females (mean monthly HIV positivity rate of 31.3% for males and 33.7% for females), with females showing significantly higher positivity compared to males (p < 0.001). The ZHCT mean monthly HIV positivity rate from index testing (32.6%) was significantly higher than that achieved through provider-initiated testing and counselling and other facility HIV testing modalities (4.1%, p < 0.001).

CONCLUSIONS

The ZHCT project has demonstrated successes in implementing index testing and PNS by attaining a high HIV positivity rate sustained over the study period. As the country moves towards HIV epidemic control, index testing and PNS are critical strategies for targeted HIV case identification.

Traditional and Web-Based Technologies to Improve Partner Notification Following Syphilis Diagnosis Among Men Who Have Sex With Men in Lima, Peru: Pilot Randomized Controlled Trial

Background

Patient-initiated partner notification (PN) following the diagnosis of a sexually transmitted infection is a critical component of disease control in men who have sex with men (MSM) sexual networks. Both printed and internet-based technologies offer potential tools to enhance traditional partner notification approaches among MSM in resource-limited settings.

Objective

This randomized controlled trial aimed to evaluate the effect of 2 different PN technologies on notification outcomes following syphilis diagnosis among MSM in Peru: a Web-based notification system and patient-delivered partner referral cards.

Methods

During 2012-2014, we screened 1625 MSM from Lima, Peru, for syphilis infection and enrolled 370 MSM with symptomatic primary or secondary syphilis (n=58) or asymptomatic latent syphilis diagnosed by serology (rapid plasma reagin, RPR, and Microhemagglutination assay for Treponema pallidum antibody; n=312). Prior to enrollment, potential participants used a computer-based self-interviewing system to enumerate their recent sexual partnerships and provide details of their 3 most recent partners. Eligible participants were randomly assigned to one of 4 intervention arms: (1) counseling and patient-initiated Web-based PN (n=95), (2) counseling with Web-based partner notification and partner referral cards (n=84), (3) counseling and partner referral cards (n=97), and (4) simple partner notification counseling (control; n=94). Self-reported partner notification was assessed after 14 days among 354 participants who returned for the follow-up assessment.

Results

The median age of enrolled participants was 27 (interquartile range, IQR 23-34) years, with a median of 2 partners (IQR 1-5) reported in the past month. Compared with those who received only counseling (arm 4), MSM provided with access to Web-based partner notification (arms 1 and 2) or printed partner referral cards (arms 2 and 3) were more likely to have notified one or more of their sexual partners (odds ratio, OR, 2.18, 95% CI 1.30-3.66; P=.003 and OR 1.68, 95% CI 1.01-2.79; P=.045, respectively). The proportion of partners notified was also higher in both Web-based partner notification (241/421, 57.2%; P<.001) and referral card (240/467, 51.4%; P=.006) arms than in the control arm (82/232, 35.3%).

Conclusions

Both new Web-based technologies and traditional printed materials support patient-directed notification and improve self-reported outcomes among MSM with syphilis. Additional research is needed to refine the use of these partner notification tools in specific partnership contexts.

Trial Registration

ClinicalTrials.gov NCT01720641; https://clinicaltrials.gov/ct2/show/NCT01720641 (Archived by WebCite at http://www.webcitation.org/70A89rJL4)

The Number of Interviews Needed to Yield New Syphilis and Human Immunodeficiency Virus Cases Among Partners of People Diagnosed With Syphilis, North Carolina, 2015

Compare syphilis investigation yield among patient groups using number needed to interview.

GOAL

To increase investigation efficiency.

STUDY DESIGN

Retrospective review of North Carolina 2015 syphilis investigations, using the number of cases needed to interview (NNTI) and the total number of cases and contacts needed to interview (TNTI) to compare yield of new syphilis and human immunodeficiency virus diagnoses between patient groups.

RESULTS

We reviewed 1646 early syphilis cases and 2181 contacts; these yielded 241 new syphilis cases (NNTI, 6.9; TNTI, 16.4) and 38 new human immunodeficiency virus cases (NNTI, 43). Interviews of women (prevalence difference [PD] = 6%, 95% confidence interval [CI], 12-16), patients <30 years old (PD = 5%, 95% CI, 1-8), and patients with titer >1:16 (PD = 5%, 95% CI, 1-9) yielded more new syphilis cases in our adjusted model; no other patient factors increased investigation yield.

CONCLUSIONS

The NNTI and TNTI are useful measures of efficiency. Prioritizing early syphilis investigation by gender, rapid plasmin reagin titer, and age provides small increases in efficiency; no other factors increased efficiency.

Partner Notification for Reduction of HIV-1 Transmission and Related Costs among Men Who Have Sex with Men: A Mathematical Modeling Study

Background

Earlier antiretroviral treatment initiation prevents new HIV infections. A key problem in HIV prevention and care is the high number of patients diagnosed late, as these undiagnosed patients can continue forward HIV transmission. We modeled the impact on the Dutch men-who-have-sex-with-men (MSM) HIV epidemic and cost-effectiveness of an existing partner notification process for earlier identification of HIV-infected individuals to reduce HIV transmission.

Methods

Reduction in new infections and cost-effectiveness ratios were obtained for the use of partner notification to identify 5% of all new diagnoses (Scenario 1) and 20% of all new diagnoses (Scenario 2), versus no partner notification. Costs and quality adjusted life years (QALYs) were assigned to each disease state and calculated over 5 year increments for a 20 year period.

Results

Partner notification is predicted to avert 18–69 infections (interquartile range [IQR] 13–24; 51–93) over the course of 5 years countrywide to 221–830 (IQR 140–299; 530–1,127) over 20 years for Scenario 1 and 2 respectively. Partner notification was considered cost-effective in the short term, with increasing cost-effectiveness over time: from €41,476 -€41, 736 (IQR €40,529-€42,147; €40,791-€42,397) to €5,773 -€5,887 (€5,134-€7,196; €5,411-€6,552) per QALY gained over a 5 and 20 year period, respectively. The full monetary benefits of partner notification by preventing new HIV infections become more apparent over time.

Conclusions

Partner notification will not lead to the end of the HIV epidemic, but will prevent new infections and be increasingly cost-effectiveness over time.

Partner notification among men who have sex with men and heterosexuals with STI/HIV: different outcomes and challenges

Partner notification effectiveness among index clients diagnosed with HIV, syphilis and/or gonorrhoea at sexually transmitted infection (STI) clinics was evaluated between 2010 and 2012. We explored percentages of identifiable, notified and tested partners by sexual preference and gender. Partner notification trends were studied using the national STI database. Men who have sex with men (n = 304), heterosexual men (n = 33) and women (n = 35) reported, respectively, 6.7, 3.8 and 2.3 partners per index. Percentages of identifiable partners differed between groups (men who have sex with men: 46%, heterosexual men: 63%, women: 87%, p < 0.001). The percentage of notified partners (of those identifiable) was lowest for heterosexual men (76%; men who have sex with men: 92%; women: 83%; p < 0.001). STI positivity rates among notified partners were high: 33%-50% depending on sexual preference. Among men who have sex with men, having HIV was associated with not notifying all identifiable partners. Percentages of notified clients at STI clinics increased between 2010 and 2012: from 13% to 19% among men who have sex with men, from 13% to 18% among heterosexual men and from 8% to 11% among women (p < 0.001 for all groups). The percentage of STI/HIV detected through partner notification increased among men who have sex with men (from 22% to 30%) and women (from 25% to 29%; p < 0.001). Unidentifiable partners among men who have sex with men, lower partner notification effectiveness for HIV and the relative large proportion of heterosexual men not notifying their partners appear to be important partner notification challenges.

Using intervention mapping for the development of a targeted secure web-based outreach strategy named SafeFriend, for Chlamydia trachomatis testing in young people at risk

BACKGROUND

Many young people at high risk for Chlamydia trachomatis (Ct) are not reached by current sexual health care systems, such as general practitioners and public sexual health care centres (sexually transmitted infection clinics).Ct is the most frequently diagnosed bacterial sexually transmitted infection (STI) among sexually active people and in particular young heterosexuals. Innovative screening strategies are needed to interrupt the transmission of Ct among young people and connect the hidden cases to care.

METHODS

Intervention Mapping (IM), a systematic approach to develop theory- and evidence-based interventions, was used to develop a strategy to target Ct testing towards young people who are currently hidden to care in The Netherlands. Both clinical users (i.e. sexual health care nurses) and public users (i.e., young people at risk for Ct) were closely involved in the IM process. A needs assessment study was carried out using semi-structured interviews among users (N = 21), a literature search and by taking lessons learned from existing screening programmes. Theoretical methods and practical applications to reach high risk young people and influence testing were selected and translated into specific programme components.

RESULTS

The IM approach resulted in the development of a secure and web-based outreach Ct screening strategy, named SafeFriend. It is developed to target groups of high-risk young people who are currently hidden to care. Key methods include web-based Respondent Driven Sampling, starting from young Ct positive sexual health care centre clients, to reach and motivate peers (i.e., sex partners and friends) to get tested for Ct. Testing and the motivation of peers were proposed as the desired behavioural outcomes and the Precaution Adoption Process Model was chosen as theoretical framework. End users, i.e., young people and sexual health care nurses were interviewed and included in the development process to increase the success of implementation.

CONCLUSIONS

IM proved useful to develop an intervention for targeted Ct testing among young people. We believe this to be the first web-based outreach screening strategy which combines chain referral sampling with the delivery of targeted Ct testing to high risk young people within their sexual and social networks.

What do we need to learn for policy decision-making on sexually transmitted infections prevention and treatment in Israel?

The rising trend of sexually transmitted infections (STIs) reported in several western countries has also affected Israel. To review epidemiological trends and to address additional issues needed for a wider overview on STIs in Israel, we analysed notified data on infectious syphilis, gonorrhoea, Chlamydia trachomatis and HIV/AIDS during 1998–2007, by age groups, and each available publication on STIs in Israel. The trend of each disease had a unique pattern, probably influenced by different screening procedures, case definition, mix of populations and better access to care for high-risk populations. Higher rates were found among patients aged 25–34 years. Rates found in different peak years for gonorrhoea, HIV, chlamydia and infectious syphilis reached 43.6, 18.9, 10.8 and 8.1 cases per 100,000 population, respectively. We compare trends to those of countries from World Health Organization (WHO) European Region and discuss interventions for subpopulations on which additional data are needed for evidence-based policy-making. Incidence rates of syphilis, gonorrhoea, chlamydia and HIV/AIDS are still low in Israel. We propose additional components needed for a more comprehensive evidence-based policy on STIs.

Partner Referral by HIV-Infected Persons to Partner Counseling and Referral Services (PCRS) - Results from a Demonstration Project

Objective:

The objectives of this article are to determine factors associated with refusal and agreement to provide partner information, and evaluate the effectiveness of referral approaches in offering PCRS.

Methods:

Index clients from 5 sites that used 3 different PCRS approaches were interviewed to obtain demographic and risk characteristics and choice of partner referral method for PCRS. Logistic regression was used to assess factors associated with providing partner information.

Results:

The percentage of index clients who refused to provide partner information varied by site (7% to 88%). Controlling for PCRS approach, index clients who were older than 25 years, male, or reported having male-male sex in the past 12 months were more likely (p <0.01) to refuse to provide partner information. Overall, 72% of named partners referred by index clients were located and offered PCRS. The proportion of partners who were located and offered PCRS differed by referral approach used, ranging from 38% using contract referral (index clients agree to notify their partners within a certain timeframe, else a disease intervention specialist or health care provider will notify them) to 98% using dual referral (index clients notify their partners with a disease intervention specialist or provider present).

Conclusion:

Success in obtaining partner information varied by the PCRS approach used and effectiveness in locating and notifying partners varied by the referral approach selected. These results provide valuable insights for enhancing partner services.

Factors associated with partner referral among patients with sexually transmitted infections in Bangladesh

Understanding the demographic, behavioural and psychosocial factors associated with partner referral for patients with sexually transmitted infections (STIs) is important for designing appropriate intervention strategies. A survey was conducted among STI clients in three government and three non-governmental organization-operated clinics in Dhaka and Chittagong city in Bangladesh. Demographic and psychosocial information was collected using a questionnaire guided by the Attitude-Social Influence-Self Efficacy model. Partner referral data were collected by verification of referral cards when partners appeared at the clinics within one month of interviewing the STI clients. Of the 1339 clients interviewed, 81% accepted partner referral cards but only 32% actually referred their partners; 37% of these referrals were done by clients randomly assigned to a single counselling session vs. 27% by clients not assigned to a counselling session (p < 0.0001). Among psychosocial factors, partner referral intention was best predicted by attitudes and perceived social norms of the STI clients. Actual partner referral was significantly associated with intention to refer partner and attitudes of the index clients. Married clients were significantly more likely to refer their partners, and clients with low income were less likely to refer partners. Intervention programmes must address psychosocial and socio-economic issues to improve partner referral for STIs in Bangladesh.

Notifying partners of patients with early syphilis in Madagascar: case-finding effectiveness and public health implications

OBJECTIVE

To evaluate the case-finding effectiveness of a clinic-based partner notification effort for early syphilis in Madagascar.

METHODS

We asked index cases who had proven early syphilis to identify and provide contact information of recent sex partners (in the past 3, 6, and 12 months for primary, secondary, and early latent syphilis, respectively). Named sex partners were contacted by index cases (patient notification) or, if approved by the index case, clinic staff members (provider notification); notified of their potential exposure to syphilis; and asked to come to the clinic for evaluation. We assessed case-finding effectiveness and calculated the 'brought-to-treatment' index (number of newly-diagnosed syphilis cases per number of index cases interviewed).

RESULTS

Of 565 index cases, 534 reported recent sex with at least one sex partner. A total of 3167 sex partners were reported, of whom 276 were contactable (9% of 3167). Providers notified 76% and cases notified 24% of these partners. 270 partners were contacted (98% of 276), and of these, 199 presented to the clinic for evaluation (74% of 270). A total of 99 partners tested positive for syphilis and received treatment (50% of 199). The 'brought-to-treatment' index was 0.18 (99 diagnoses per 565 index cases).

CONCLUSION

Partner notification was possible in this setting, resulting in treatment of syphilis-infected individuals who otherwise would likely have remained untreated. However, given <10% of the partners reported by index cases were contactable; the results highlight the limitations of partner notification and the need for additional sexually transmitted infection control strategies.

Effect of single session counselling on partner referral for sexually transmitted infections management in Bangladesh

OBJECTIVES

This study evaluated the role of single session counselling on partner referral among index cases diagnosed as having sexually transmitted infections (STIs) in Bangladesh.

METHODS

A quasirandomised trial was conducted in 1339 index cases with symptomatic STIs in 3 public and 3 non-government organisation operated clinics.

RESULTS

Out of 1339 index cases, partner referral was achieved by 37% in the counselling group and 27% in the non-counselling group. Index cases in the counselling group and non-counselling group were similar in terms of condom use rates, STI symptoms and duration of disease. A quarter of the index cases reported having more than one sex partner in last 3 months, and 39% reported having commercial sex partners. Only 8% of the index cases reported using condoms during their last sex act. Partner referral rates were higher among index clients with higher age, higher income, those who attended NGO clinics, those who had only one partner and among those who had no commercial partners, but counselling had significantly positive impact in all of these subgroups. In multivariate analysis, the probability of partner referral was 1.3 times higher among index cases in the counselling group (prevalence ratio 1.3; 95% CI 1.1 to 1.6) as compared to index cases in the non-counselling group.

CONCLUSIONS

Patient-oriented single session counselling was found to have a modest but significant effect in increasing partner referral for STIs in Bangladesh, greater emphasis should be placed on examining further development and dissemination of partner referral counselling in STI care facilities.

Focusing HIV prevention on those most likely to transmit the virus

Despite some success in reducing HIV incidence, the global epidemic continues to grow. For every person with AIDS in developing countries placed on treatment in 2005, many others were newly infected. We need more effective prevention programs that focus interventions on those most at risk for HIV transmission (MART), particularly those with 1) high behavioral risk and 2) high viral loads due to acute or recent infection, co-infections with other diseases, high viral set points, or untreated AIDS. This article provides examples of how prevention programs can incorporate emerging testing technologies and social/behavioral approaches to reach these individuals, their partners, and the social networks where active transmission is occurring.

Effects of partner notification on reducing gonorrhea incidence rate

OBJECTIVE

The objective of this study was to estimate the effectiveness of partner notification (PN) by linking measures of PN with the gonorrhea incidence rate in New York State exclusive of New York City.

STUDY DESIGN

Gonorrhea cases were identified from the Communicable Disease Confidential Case Reports system. Case interview data were obtained from the case management database. Gonorrhea incidence data and interview data were aggregated from individual records and then linked at the county level.

RESULTS

From 1992 to 2002, 100,756 gonorrhea cases were reported and 37% were interviewed. A total of 34,807 partners were elicited from 37,393 index cases: 18,291 (52.5%) partners sought medical evaluation, 10,159 (29.2%) received preventive treatment, and 7,474 (21.5%) were infected and treated. The gonorrhea incidence rate was inversely correlated with the percent of partners given preventive treatment and positively related to the percent of infected partners.

CONCLUSIONS

Our study adds new evidence that PN is an effective mechanism to detect new cases and interrupt disease transmission within communities.

Partner Notification for Sexually Transmitted Diseases

Partner notification, a principal means of controlling sexually transmitted diseases, has traditionally been performed by public health professionals. They interview infected persons and contact the sex partners of these persons to notify them and convince them of the need to seek evaluation and treatment (known as "provider referral"). This notification method is labor intensive; the typical alternative to provider referral is to leave notification to the infected person (known as "patient referral"). However, innovations in partner notification, often created by public health professionals responsible for the practice, have yielded adjuncts and complements to both provider and patient referral. The present review article covers 4 areas of innovation: (1) enhancements to patient referral instructions and provider interview techniques, (2) use of the Internet in partner notification, (3) the emerging influence of network methods, and (4) expedited partner therapy, principally through patient-delivered medications or prescriptions. Partner notification remains necessary, and flexibility, openness to the use of multiple methods, and collaboration are likely to be helpful.

Transmission network analysis to complement routine tuberculosis contact investigations

OBJECTIVE

We examined the feasibility and value of network analysis to complement routine tuberculosis (TB) contact investigation procedures during an outbreak.

METHODS

We reviewed hospital, health department, and jail records and interviewed TB patients. Mycobacterium tuberculosis isolates were genotyped. We evaluated contacts of TB patients for latent TB infection (LTBI) and TB, and analyzed routine contact investigation data, including tuberculin skin test (TST) results. Outcomes included number of contacts identified, number of contacts evaluated, and their TST status. We used network analysis visualizations and metrics (reach, degree, betweenness) to characterize the outbreak.

RESULTS

secondary TB patients and more than 1200 contacts. Genotyping detected a 21-band pattern of a strain W variant. No HIV-infected patients were diagnosed. Contacts prioritized by network analysis were more likely to have LTBI than nonprioritized contacts (odds ratio=7.8; 95% confidence interval=1.6, 36.6). Network visualizations and metrics highlighted patients central to sustaining the outbreak and helped prioritize contacts for evaluation.

CONCLUSIONS

A network-informed approach to TB contact investigations provided a novel means to examine large quantities of data and helped focus TB control.

Sex partner selection, social networks, and repeat sexually transmitted infections in young men: a preliminary report

GOAL

The goal of this study was to examine the risk for repeat sexually transmitted infections (STIs) associated with reducing the number of sex partners who come from within the social networks of males 13 to 25 years old in Baltimore, Maryland, and Denver, Colorado.

STUDY

Asymptomatic males diagnosed with chlamydia and/or gonorrhea as part of an asymptomatic chlamydia and gonorrhea male screening project were recruited and interviewed about their sexual behaviors and their perceptions of social characteristics and sexual behaviors of their sex partners. We characterized the sex partners of each participant as belonging to or not belonging to his social network. We examined whether a decrease in percentage of sex partners who were in the participant's social network was associated with repeat infection.

RESULTS

There were 47 participants in Baltimore and 92 in Denver. In both cities, there was a trend toward a finding that decreasing the percentage of sex partners belonging to a participant's social network was protective for repeat STI.

CONCLUSION

These data suggest that interventions may need to be designed to reduce the prevalence of infection in the social networks of infected men.

Divergent Approaches to Partner Notification for Sexually Transmitted Infections Across the European Union

OBJECTIVE

The objective of this study was to characterize partner notification (PN) policy and practice for sexually transmitted infections (STIs) in the European Union (EU) and Norway.

GOAL

The goal of this study was to promote European good practice in PN.

STUDY

This study consisted of a cross-sectional survey using a structured questionnaire to national STI surveillance leads.

RESULTS

Considerable heterogeneity exists in approaches to PN. In 2 countries, PN is compulsory for notifiable STIs; and in 13, it is voluntary. Most countries use patient referral but 5 of 15 also offer provider referral. Activity level varies by country and disease. Etiologic treatment of contacts is most common; 5 usually offer epidemiologic treatment and patient-expedited treatment is unusual. Similarities exist with provision mainly by specialized STI treatment services for bacterial STIs.

CONCLUSIONS

This divergence in approach calls for the setting of minimum standards for PN delivery together with mechanisms for establishing and sharing best practice. Further research must identify monitoring systems for inclusion in routine surveillance.

Innovative Approaches to the Prevention and Control of Bacterial Sexually Transmitted Infections

Bacterial STI continues to be a major problem in developed nations. Research and evolving standards of public health practice are cause for optimism and concern. Innovations in case-finding and treatment, particularly the application of NAATs to test for chlamydial infection in nonclinical settings, are successes that merit more widespread application. EPT, selective STI screening in men, and rescreening are all promising, but are not yet in widespread use and may face significant operational barriers. To date, public health efforts to alter sexual behavior, at least through specific interventions, are more discouraging. Although some behavioral interventions have been effective, none has been widely instituted. Moreover, the likelihood that existing behavioral interventions will be widely applied seems remote. Future research efforts in this area will need to focus less on proof-of-concept efficacy trials and more on developing and testing sustainable, cost-effective interventions that focus on those at greatest risk and that can be scaled-up within the existing public health infrastructure.

Case-Finding Effectiveness of Partner Notification and Cluster Investigation for Sexually Transmitted Diseases/HIV

OBJECTIVE

To assess the case-finding effectiveness of partner notification(PN) and cluster investigation for sexually transmitted disease (STD)/human immunodeficiency virus (HIV).

STUDY

Literature review and quantitative summary.

RESULTS

Since 1975, the median case-finding yield for syphilis, gonorrhea, and chlamydia PN reported in the literature is about 1 new case found for every 4 or 5 cases interviewed. The yield from HIV PN is approximately half as large, although there is substantial variability in yield across reports for each disease. Published reports underline the central role provider referral plays in effective PN and case-finding. Successful PN is more likely with index cases who are of majority ethnicity and detected through screening or spontaneous presentation for care with symptoms and with partners with whom index cases have had sexual contact that is recent, frequent, and of long duration. The case-finding yield for HIV PN also is much higher when cases are diagnosed through confidential, rather than anonymous, testing. Cluster investigation and related strategies tend to have lower case-finding yields than PN but can play a very useful case-finding role, especially in settings with high disease incidence.

CONCLUSIONS

STD/HIV PN and cluster investigation can contribute meaningfully to case finding. More research is needed to strengthen the empiric foundation of PN and related strategies, including the impact they have on disease transmission.

Sexually transmissible infections other than HIV

Sexually transmitted infections (STIs) are notable for their fastidious requirements for transmission and growth in the laboratory and for their high physical and psychosocial morbidity. The combination of subtle or absent symptoms and stigma preventing the seeking of health care, leaves many infections undiagnosed. The development of nucleic-acid amplification tests heralded a new era in sensitive and robust diagnostic procedures for STIs. Unfortunately, many of these tests are not commercially available or are too expensive for the populations that need them most. Single-dose oral azithromycin has improved the treatment of several bacterial STIs, but quinolones are rapidly becoming ineffective for gonorrhoea. Self-treatment of genital warts with podophyllotoxin or imiquimod preparations is attractive to patients and might be cost effective for health services. The prospect of effective vaccines against genital papillomaviruses in the near future is real. Such vaccines could reduce the global incidence of some anogenital cancers. Episodic treatment of genital herpes is getting easier and cheaper, and suppressive treatment can reduce transmission to regular sexual partners. A vaccine against herpes simplex virus type 2 has shown some limited efficacy. Ultimately, better control of STIs, and reduction of their contribution to the spread of HIV, will require a broad health-sector response with adequate resourcing, and a change in social and political attitudes.