The Typhoid Fever Surveillance in Africa Program (TSAP): Clinical, Diagnostic, and Epidemiological Methodologies.

BACKGROUND: New immunization programs are dependent on data from surveillance networks and disease burden estimates to prioritize target areas and risk groups. Data regarding invasive Salmonella disease in sub-Saharan Africa are currently limited, thus hindering the implementation of preventive measures. The Typhoid Fever Surveillance in Africa Program (TSAP) was established by the International Vaccine Institute to obtain comparable incidence data on typhoid fever and invasive nontyphoidal Salmonella (iNTS) disease in sub-Saharan Africa through standardized surveillance in multiple countries. METHODS: Standardized procedures were developed and deployed across sites for study site selection, patient enrolment, laboratory procedures, quality control and quality assurance, assessment of healthcare utilization and incidence calculations. RESULTS: Passive surveillance for bloodstream infections among febrile patients was initiated at thirteen sentinel sites in ten countries (Burkina Faso, Ethiopia, Ghana, Guinea-Bissau, Kenya, Madagascar, Senegal, South Africa, Sudan, and Tanzania). Each TSAP site conducted case detection using these standardized methods to isolate and identify aerobic bacteria from the bloodstream of febrile patients. Healthcare utilization surveys were conducted to adjust population denominators in incidence calculations for differing healthcare utilization patterns and improve comparability of incidence rates across sites. CONCLUSIONS: By providing standardized data on the incidence of typhoid fever and iNTS disease in sub-Saharan Africa, TSAP will provide vital input for targeted typhoid fever prevention programs.

A meta-analysis of the efficacy of HIV/AIDS prevention interventions in Asia, 1995-2009.

The HIV/AIDS epidemic continues to grow in pockets across Asia, despite early successes at curtailing its spread in countries like Thailand. Recent evidence documents dramatic increases in incidence among risk groups and, alarmingly, the general population. This meta-analysis summarizes the sexual risk-reduction interventions for the prevention of HIV-infection that have been evaluated in Asia. Sexual risk-reduction outcomes (condom use, number of sexual partners, incident sexually transmitted infections [STI], including HIV) from 46 behavioral intervention studies with a comparison condition and available by August 2010 were included. Overall, behavioral interventions in Asia consistently reduced sexual risk outcomes. Condom use improved when interventions sampled more women, included motivational content, or did not include STI testing and treatment. Incident HIV/STI efficacy improved most when interventions sampled more women, were conducted more recently, or when they included STI counseling and testing. Sexual frequency efficacy improved more in interventions that were conducted in countries with lower human development capacities, when younger individuals were sampled, or when condom skills training was included. Behavioral interventions for reducing sexual risk in Asia are efficacious; yet, the magnitude of the effects co-varies with specific intervention and structural components. The impact of structural factors on HIV intervention efficacy must be considered when implementing and evaluating behavioral interventions. Implications and recommendations for HIV/AIDS interventions are discussed.

Efficacy of behavioral interventions to increase condom use and reduce sexually transmitted infections: a meta-analysis, 1991 to 2010.

OBJECTIVE: In the absence of an effective HIV vaccine, safer sexual practices are necessary to avert new infections. Therefore, we examined the efficacy of behavioral interventions to increase condom use and reduce sexually transmitted infections (STIs), including HIV. DESIGN: Studies that examined a behavioral intervention focusing on reducing sexual risk, used a randomized controlled trial or a quasi-experimental design with a comparison condition, and provided needed information to calculate effect sizes for condom use and any type of STI, including HIV. METHODS: Studies were retrieved from electronic databases (eg, PubMed, PsycINFO) and reference sections of relevant papers. Forty-two studies with 67 separate interventions (N = 40,665; M age = 26 years; 68% women; 59% Black) were included. Independent raters coded participant characteristics, design and methodological features, and intervention content. Weighted mean effect sizes, using both fixed-effects and random-effects models, were calculated. Potential moderators of intervention efficacy were assessed. RESULTS: Compared with controls, intervention participants increased their condom use [d+ = 0.17, 95% confidence interval (CI) = 0.04, 0.29; k = 67], had fewer incident STIs (d+ = 0.16, 95% CI = 0.04, 0.29; k = 62), including HIV (d+ = 0.46, 95% CI = 0.13, 0.79; k = 13). Sample (eg, ethnicity) and intervention features (eg, skills training) moderated the efficacy of the intervention. CONCLUSIONS: Behavioral interventions reduce sexual risk behavior and avert STIs and HIV. Translation and widespread dissemination of effective behavioral interventions are needed.

Adherence to highly active antiretroviral therapy (HAART): a meta-analysis.

This meta-analysis synthesizes eighty-four observational studies, conducted across twenty countries, to determine the mean proportion of people who reported ≥90% adherence to prescribed highly active antiretroviral therapy (HAART) and to identify the factors associated with high levels of adherence. Eight electronic databases were searched to locate all relevant studies available by January 2010, which were then coded for sample characteristics and adherence levels. The average rate of reporting ≥90% adherent HAART adherence is 62%. However, this proportion varies greatly across studies. In particular, a greater proportion of individuals maintaining ≥90% adherence to HAART is more likely in studies with higher proportions of men who have sex with men (MSM) and lower proportions of injection drug users (IDU), with participants in an earlier stage of infection, and in studies conducted in countries characterized by lower Human Development Index (HDI) scores.

A network-individual-resource model for HIV prevention.

HIV is transmitted through dyadic exchanges of individuals linked in transitory or permanent networks of varying sizes. A theoretical perspective that bridges key individual level elements with important network elements can be a complementary foundation for developing and implementing HIV interventions with outcomes that are more sustainable over time and have greater dissemination potential. Toward that end, we introduce a Network-Individual-Resource (NIR) model for HIV prevention that recognizes how exchanges of resources between individuals and their networks underlies and sustains HIV-risk behaviors. Individual behavior change for HIV prevention, then, may be dependent on increasing the supportiveness of that individual's relevant networks for such change. Among other implications, an NIR model predicts that the success of prevention efforts depends on whether the prevention efforts (1) prompt behavior changes that can be sustained by the resources the individual or their networks possess; (2) meet individual and network needs and are consistent with the individual's current situation/developmental stage; (3) are trusted and valued; and (4) target high HIV-prevalence networks.

Efficacy of HIV prevention interventions in Latin American and Caribbean nations, 1995-2008: a meta-analysis.

This meta-analysis synthesized 37 HIV prevention interventions (from 28 studies) that were evaluated in Latin American and Caribbean nations. These studies were obtained through systematic searches of English, Spanish, and Portuguese-language databases available as of January 2009. Overall, interventions significantly increased knowledge (d = 0.40) and condom use (d = 0.25) but the effects varied widely. Interventions produced more condom use when they focused on high-risk individuals, distributed condoms, and explicitly addressed social-cultural components. The best-fitting models utilized factors related to geography, especially indices of a nations' human development index (HDI) and income inequality (i.e., Gini index). Interventions that provided at least 3 h of content succeeded better when HDI and income inequality were lower, suggesting that intensive HIV prevention activities succeed best where the need is greatest. Implications for HIV intervention development in Latin America and the Caribbean are discussed.