Jesus Maria Garcia Calleja

Transmission of HIV-1 infection in sub-Saharan Africa and effect of elimination of unsafe injections

During the past year, a group has argued that unsafe injections are a major if not the main mode of HIV-1 transmission in sub-Saharan Africa. We review the main arguments used to question the epidemiological interpretations on the lead role of unsafe sex in HIV-1 transmission, and conclude there is no compelling evidence that unsafe injections are a predominant mode of HIV-1 transmission in sub-Saharan Africa. Conversely, though there is a clear need to eliminate all unsafe injections, epidemiological evidence indicates that sexual transmission continues to be by far the major mode of spread of HIV-1 in the region. Increased efforts are needed to reduce sexual transmission of HIV-1.

HIV prevalence and trends in sub-Saharan Africa: no decline and large subregional differences

BACKGROUND Expansion of HIV surveillance systems in sub-Saharan Africa is leading to downward adjustments to the size of the AIDS epidemic. However, only analysis of surveillance data from the same populations over time can provide insight into trends of HIV prevalence. We have used data from the same antenatal clinics to document recent empirical trends. METHODS We collated data from antenatal clinics on HIV prevalence between 1997 and 2003. Data were obtained from 140?000 pregnant women attending more than 300 antenatal clinics in 22 countries in sub-Saharan Africa. Additionally, long-term trend data are available for 57 urban areas and provinces. FINDINGS Median HIV prevalence in 148 antenatal clinic sites in southern Africa increased from 21.3% (IQR 11.5-28.2%) in 1997/98 to 23.8% (15.6-29.2%) in 2002. At more than half the sites (58%) an increase of at least one-tenth was noted, but at a fifth of sites, prevalence dropped by at least one-tenth. In eastern Africa, median HIV prevalence decreased from 12.9% (7.0-16.9%) in 1997/98 to 8.5% (5.3-13.0%) in 2002, with prevalence rising in four (7%) sites, but falling at 25 (43%) sites. In west Africa, median HIV prevalence was 3.5% (2.2-5.9%) and 3.2% (2.3-6.1%) for 1997/98 and 2002, respectively, with reductions and increases in prevalence being noted in equal proportions. The long-term trends in urban areas in sub-Saharan Africa show a similar pattern, with increasing evidence of stabilisation during the past 2-3 years compared with the previous decade. INTERPRETATION Evidence from surveillance of mostly urban antenatal clinic attendees indicates that the growth in the AIDS epidemic in sub-Saharan Africa has levelled off since the late 1990s but only eastern Africa shows a decline in HIV prevalence. Very large differences persist between subregions. Workers planning a response to the AIDS epidemic must take more careful consideration of these variations to allow locally appropriate responses to the epidemic.

Accuracy of serological assays for detection of recent infection with HIV and estimation of population incidence: a systematic review

We systematically reviewed the accuracy of serological tests for recent infections with HIV that have become widely used for measuring population patterns incidence of HIV. Across 13 different assays, sensitivity to detect recent infections ranged from 42-100% (median 89%). Specificity for detecting established infections was between 49.5% and 100% (median 86.8%) and was higher for infections of durations longer than 1 year (median 98%, range 31.5-100.0). For four different assays, comparisons were made between assay-derived population incidence estimates and a reference incidence estimate. The median percentage difference between the assay-derived incidence and reference incidence was 26.0%. Serological assays have reasonable sensitivity for the detection of recent infection with HIV, but are vulnerable to misclassifying established infections as recent-potentially leading to biases in incidence estimates. This conclusion is highly qualified by the apparent absence of a standardised approach to assay evaluation. There is an urgent need for an internationally agreed framework for evaluating and comparing these tests.

HIV Due to Female Sex Work: Regional and Global Estimates

Introduction Female sex workers (FSWs) are at high risk of HIV infection. Our objective was to determine the proportion of HIV prevalence in the general female adult population that is attributable to the occupational exposure of female sex work, due to unprotected sexual intercourse. Methods Population attributable fractions of HIV prevalence due to female sex work were estimated for 2011. A systematic search was conducted to retrieve required input data from available sources. Data gaps of HIV prevalence in FSWs for 2011 were filled using multilevel modeling and multivariate linear regression. The fraction of HIV attributable to female sex work was estimated as the excess HIV burden in FSWs deducting the HIV burden in FSWs due to injecting drug use. Results An estimated fifteen percent of HIV in the general female adult population is attributable to (unsafe) female sex work. The region with the highest attributable fraction is Sub Saharan Africa, but the burden is also substantial for the Caribbean, Latin America and South and Southeast Asia. We estimate 106,000 deaths from HIV are a result of female sex work globally, 98,000 of which occur in Sub-Saharan Africa. If HIV prevalence in other population groups originating from sexual contact with FSWs had been considered, the overall attributable burden would probably be much larger. Discussion Female sex work is an important contributor to HIV transmission and the global HIV burden. Effective HIV prevention measures exist and have been successfully targeted at key populations in many settings. These must be scaled up. Conclusion FSWs suffer from high HIV burden and are a crucial core population for HIV transmission. Surveillance, prevention and treatment of HIV in FSWs should benefit both this often neglected vulnerable group and the general population.

Status of the HIV/AIDS epidemic and methods to monitor it in the Latin America and Caribbean region.

&NA; The paper presented is a review of the available epidemiological data on the situation in the Latin America and Caribbean (LAC) region, and looks at HIV prevalence in specific population groups. At the end of 2001, HIV remains an important health issue in the LAC region. Twelve countries in the region have an estimated prevalence of 1% or higher among pregnant women. Most of the LAC countries with generalized epidemics are located in the Caribbean basin. In the past decade there has been a slow but continuous increase in HIV prevalence rates among the general population and vulnerable groups, although information in some countries is limited. In many countries, the highest HIV prevalence among vulnerable groups is found among men who have sex with men. HIV infections related to injecting drug use are concentrated in the countries of the Southern Cone and Brazil. HIV is well anchored in the region, concentrated in vulnerable groups in most countries, but with an increasing presence in some countries in the general population. There is a need to improve data collection and introduce new tools to monitor behavior trends and the impact of interventions.

HIV surveillance in MENA: recent developments and results

Objectives To provide an overview of the current level of development and results from the national HIV surveillance systems of the 23 countries of the Middle East and North Africa (MENA), and to assess the quality of HIV surveillance systems in the period 2007–2011. Methods A questionnaire was used to collect the information about the structure, activities and the results of HIV surveillance systems from the National AIDS Programmes. Assessment of the quality was based on four indicators: timeliness of data collection, appropriateness of populations under surveillance, consistency of the surveillance sites and groups measured over time, and coverage of the surveillance system. Results Only in four countries did surveillance systems enable assessment of epidemic trends in the same populations and locations over time, such as in pregnant women (Morocco, Iran), injecting drug users (Iran, Pakistan), female sex workers (Djibouti, Morocco) and male sex workers (Pakistan). There is increasing evidence of HIV infection being firmly established in at least one of the populations most at risk of HIV in nine MENA countries, while lower risk populations show elevated HIV prevalence in South Sudan, Djibouti and some parts of Somalia. Conclusions The performance of HIV surveillance systems in several of the MENA countries has improved in recent years. The extent of HIV epidemics in the populations most at risk of HIV is still largely unknown in 10 countries. Multiple data sources that most of the countries still lack would enable indirectly estimation not only of the patterns of HIV epidemics but also the effectiveness of HIV responses.

Outcomes and Impact of HIV Prevention, ART and TB Programs in Swaziland - Early Evidence from Public Health Triangulation

Introduction Swaziland’s severe HIV epidemic inspired an early national response since the late 1980s, and regular reporting of program outcomes since the onset of a national antiretroviral treatment (ART) program in 2004. We assessed effectiveness outcomes and mortality trends in relation to ART, HIV testing and counseling (HTC), tuberculosis (TB) and prevention of mother to child transmission (PMTCT). Methods Data triangulated include intervention coverage and outcomes according to program registries (2001-2010), hospital admissions and deaths disaggregated by age and sex (2001-2010) and population mortality estimates from the 1997 and 2007 censuses and the 2007 demographic and health survey. Results By 2010, ART reached 70% of the estimated number of people living with HIV/AIDS with CD4<350/mm3, with progressively improving patient retention and survival. As of 2010, 88% of health facilities providing antenatal care offered comprehensive PMTCT services. The HTC program recorded a halving in the proportion of adults tested who were HIV-infected; similarly HIV infection rates among HIV-exposed babies halved from 2007 to 2010. Case fatality rates among hospital patients diagnosed with HIV/AIDS started to decrease from 2005–6 in adults and especially in children, contrasting with stable case fatality for other causes including TB. All-cause child in-patient case fatality rates started to decrease from 2005–6. TB case notifications as well as rates of HIV/TB co-infection among notified TB patients continued a steady increase through 2010, while coverage of HIV testing and CPT for co-infected patients increased to above 80%. Conclusion Against a background of high, but stable HIV prevalence and decreasing HIV incidence, we documented early evidence of a mortality decline associated with the expanded national HIV response since 2004. Attribution of impact to specific interventions (versus natural epidemic dynamics) will require additional data from future household surveys, and improved routine (program, surveillance, and hospital) data at district level.

Is the HIV sentinel surveillance system adequate in China? Findings from an evaluation of the national HIV sentinel surveillance system.

BACKGROUND An external evaluation was conducted to assess the performance of the national HIV sentinel surveillance system (HSS), identify operational challenges at national and local levels and provide recommendations for improvement. METHODS The United States Centers for Disease Control and Preventions (CDC) Updated Guidelines for Evaluating Public Health Surveillance Systems were followed to assess the key attributes of HSS. Comprehensive assessment activities were conducted, including: using a detailed checklist to review surveillance guidelines, protocols and relevant documents; conducting self-administered, anonymous surveys with 286 local China CDC staff; and carrying out field observations in 32 sentinel sites in four provinces. RESULTS China has built an extensive HSS with 1888 sentinel sites to monitor HIV epidemic trends by population groups over time. The strengths of HSS lie in its flexibility, simplicity, usefulness and increase in coverage in locations and populations. With its rapid expansion in 2010, HSS faces challenges in maintaining acceptability, timeliness, data quality, representativeness and sustainability. RECOMMENDATIONS Implementation of the national guidelines should be standardized by strengthening training, monitoring and supervision of all staff involved, including community-based organizations. National surveillance guidelines need to be revised to strengthen data quality and representativeness, particularly to include specific instructions on HIV testing result provision, collection of identifying information, sample size and sampling methods particularly for men who have sex with men (MSM), collection of refusal information, and data interpretation. Sustainability of Chinas HSS could be strengthened by applying locally tailored surveillance strategies, strengthening coordination and cooperation among government agencies and ensuring financial and human resources.

Availability and Quality of Size Estimations of Female Sex Workers, Men Who Have Sex with Men, People Who Inject Drugs and Transgender Women in Low- and Middle-Income Countries

Objective To assess the availability and quality of population size estimations of female sex workers (FSW), men who have sex with men (MSM), people who inject drug (PWID) and transgender women. Methods Size estimation data since 2010 were retrieved from global reporting databases, Global Fund grant application documents, and the peer-reviewed and grey literature. Overall quality and availability were assessed against a defined set of criteria, including estimation methods, geographic coverage, and extrapolation approaches. Estimates were compositely categorized into ‘nationally adequate’, ‘nationally inadequate but locally adequate’, ‘documented but inadequate methods’, ‘undocumented or untimely’ and ‘no data.’ Findings Of 140 countries assessed, 41 did not report any estimates since 2010. Among 99 countries with at least one estimate, 38 were categorized as having nationally adequate estimates and 30 as having nationally inadequate but locally adequate estimates. Multiplier, capture-recapture, census and enumeration, and programmatic mapping were the most commonly used methods. Most countries relied on only one estimate for a given population while about half of all reports included national estimates. A variety of approaches were applied to extrapolate from sites-level numbers to national estimates in two-thirds of countries. Conclusions Size estimates for FSW, MSM, PWID and transgender women are increasingly available but quality varies widely. The different approaches present challenges for data use in design, implementation and evaluation of programs for these populations in half of the countries assessed. Guidance should be further developed to recommend: a) applying multiple estimation methods; b) estimating size for a minimum number of sites; and, c) documenting extrapolation approaches.

Has the quality of serosurveillance in low- and middle-income countries improved since the last HIV estimates round in 2007? Status and trends through 2009

Background HIV surveillance systems aim to monitor trends of HIV infection, the geographical distribution and its magnitude, and the impact of HIV. The quality of HIV surveillance is a key element in determining the uncertainty ranges around HIV estimates. This paper aims to assess the quality of HIV surveillance systems in low- and middle-income countries in 2009 compared with 2007. Methods Four dimensions related to the quality of surveillance systems are assessed: frequency and timeliness of data; appropriateness of populations; consistency of locations and groups; and representativeness of the groups. An algorithm for scoring the quality of surveillance systems was used separately for low and concentrated epidemics and for generalised epidemics. Results The number of countries categorised as fully functioning in 2009 was 35, down from 40 in 2007. 47 countries were identified as partially functioning, while 56 were categorised as poorly functioning. When compared with 2007, the quality of HIV surveillance remains similar. The number of ANC sites in sub-Saharan Africa has increased over time. The number of countries with low and concentrated epidemics that do not have functioning HIV surveillance systems has increased from 53 to 56 between 2007 and 2009. Conclusion Overall, the quality of surveillance in low- and middle-income countries has remained stable. Still too many countries have poorly functioning surveillance systems. Several countries with generalised epidemics have conducted more than one population-based survey which can be used to confirm trends. In countries with concentrated or low-level epidemics, the lack of data on high-risk populations remains a challenge.