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author:("laferla, R")
1.  The 2005 Workbook: an improved tool for estimating HIV prevalence in countries with low level and concentrated epidemics 
Sexually Transmitted Infections  2006;82(Suppl 3):iii41-iii44.
This paper describes improvements and updates to an established approach to making epidemiological estimates of HIV prevalence in countries with low level and concentrated epidemics.
The structure of the software used to make estimates is briefly described, with particular attention to changes and improvements.
The approach focuses on identifying populations which, through their behaviour, are at high risk of infection with HIV or who are exposed through the risk behaviour of their sexual partners. Estimates of size and HIV prevalence of these populations allow the total number of HIV infected people in a country or region to be estimated. Major changes in the software focus on the move away from short term projections and towards developing an epidemiological curve that more accurately represents the change in prevalence of HIV over time. The software continues to provide an output file for use in the Spectrum software so as to estimate the demographic impact of HIV infection at country level.
PMCID: PMC2576736  PMID: 16735292
concentrated epidemics; HIV surveillance; high risk populations; methods; prevalence
2.  Clients of sex workers in different regions of the world: hard to count 
Sexually Transmitted Infections  2006;82(Suppl 3):iii26-iii33.
To estimate the proportion of the male population that reports having paid for sex in different regions.
Clients of sex workers were identified from representative samples of men asked in face‐to‐face interviews whether they had had sex in exchange for money or whether they had paid for sex, in the last 12 months. A total of 78 national household surveys and nine city based surveys were selected for inclusion. Where such surveys were not available, results of behavioural surveillance surveys and of research studies were also used. Using national estimates, a median percentage of men who reported paying for sex was calculated for each region.
The median percentage of men who exchanged sex for money in the last 12 months in all regions was around 9–10%, with estimates from 13% to 15% in Central African region, 10 to 11% in Eastern and southern Africa, and 5–7% in Asia and Latin America. Estimates for men who paid sex were much lower at around 2–3% with ranges from 7% in the South African region to 1% in Asia and West Africa.
Although errors of measurement and critical issues of definitions and interpretation exist, this compilation represents a first attempt to obtain reasonably coherent estimates of the proportion of men who were clients of sex workers at regional level. Large discrepancies between regions were found. Further improvements in national estimates will be critical to monitor coverage of HIV prevention programmes for sex workers and clients, and to improve estimates of national HIV infection prevalence levels in low and concentrated HIV epidemics.
PMCID: PMC2576731  PMID: 16735289
clients of sex workers; HIV epidemic; sex workers; sexual behaviour; size estimates
3.  Estimates of the number of female sex workers in different regions of the world 
Sexually Transmitted Infections  2006;82(Suppl 3):iii18-iii25.
To collect estimated numbers of female sex workers (FSW) and present proportions of FSW in the female population (FSW prevalence) in different regions of the world.
Subnational and national estimated numbers of FSW reported in published and unpublished literature, as well as from field investigators involved in research or interventions targeted at FSW, were collected. The proportion of FSW in the adult female population was calculated. Subnational estimates were extrapolated to national estimates if appropriate. Population surveys were scanned for proportions of adult women having sex in exchange for money or goods.
In sub‐Saharan Africa, the FSW prevalence in the capitals ranged between 0.7% and 4.3% and in other urban areas between 0.4% and 4.3%. Population surveys from this same region yielded even higher proportions of women involved in transactional sex. The national FSW prevalence in Asia ranged between 0.2% and 2.6%; in the ex‐Russian Federation between 0.1% and 1.5%; in East Europe between 0.4% and 1.4%; in West Europe between 0.1% and 1.4%; and in Latin America between 0.2% and 7.4%. Estimates from rural areas were only available from one country.
Although it is well known and accepted that FSW are a highly vulnerable group in the scope of the HIV epidemic, most countries in the world do not know the size of this population group. The estimates of the prevalence of FSW presented in this paper show how important this hard‐to‐reach population group is in all parts of the world.
PMCID: PMC2576726  PMID: 16735288
female sex workers; population size; vulnerable populations; HIV surveillance
4.  Estimating the number of men who have sex with men in low and middle income countries 
Sexually Transmitted Infections  2006;82(Suppl 3):iii3-iii9.
To collect and analyse published and unpublished surveillance and research data on the prevalence of same sex sexual activity among male adults (including male‐to‐female transgenders and sex workers) in low and middle income countries.
Key indicators were operationalised (ever sex with a man, sex with a man last year, high risk sex last year (as defined by unprotected anal sex or commercial sex)) and a database was designed for data collection. Searches were conducted (PubMed, databases (US Census Bureau, World Bank, conferences)) and regional informants helped. Reference reports were used to assess the methodology and quality of information in each record. The best data available per region were identified and indicator estimates were used to propose regional range estimates.
Of 561 studies on male sexual behaviour and/or MSM population characteristics, 67 addressed prevalence of sex between men, with diverse numbers per region and virtual unavailability in sub‐Saharan Africa, Middle East/North Africa, and the English speaking Caribbean. Overall, data on lifetime prevalence of sex with men (among males) yielded figures of 3–5% for East Asia, 6–12% for South and South East Asia, 6–15% for Eastern Europe, and 6–20% for Latin America. Last year figures were approximately half of lifetime figures, and prevalence of high risk sex among MSM last year was approximately 40–60% in all regions except South Asia, where it is 70–90%.
Data available on the prevalence of male same sex sexual activity across regions are scarce (non‐existent in some areas), with validity and comparability problems. In South and South East Asia, Eastern Europe, and Latin America, a lifetime prevalence of 6–20% was estimated, with smaller figures in East Asia. A cross cultural analysis of terminology and practices is needed, as is continued work on epidemiological and social analysis of male‐male sexual practices in societies across regions.
PMCID: PMC2576725  PMID: 16735290
men who have sex with men; sexual behaviour; global estimates; HIV; scientific review
5.  The quality of sero-surveillance in low- and middle-income countries: status and trends through 2007 
Sexually Transmitted Infections  2008;84(Suppl_1):i85-i91.
To examine the quality of HIV sero-surveillance systems in 127 low-income and middle-income countries by 2007, as well as gaps in data needed for reliable estimates of HIV prevalence and size of populations at risk for infection.
The quality of countries’ surveillance systems was scored using information from 2001 through 2007. Sero-surveillance data were compiled from the US Census Bureau’s HIV/AIDS Surveillance Database, from countries’ national HIV surveillance reports available to UNAIDS, from demographic and health survey (DHS) data, from the scientific literature and from countries’ Estimation and Projection Programme (EPP) data files. The quality of systems was scored according to the classification of the epidemic in each country (generalised, concentrated or low-level).
The number of countries categorised as fully functioning in 2007 was 40. 43 countries were identified as partially functioning while 44 were categorised as poorly functioning. Low scores were most often attributed to a lack of recent data or data from appropriate risk groups.
Many countries still have poorly functioning surveillance systems. The inclusion of HIV testing in national population-based surveys in recent years has resulted in some countries with generalised epidemics receiving higher coverage scores, but many countries with concentrated or low-level epidemics continue to lack data on high-risk populations.
PMCID: PMC2569836  PMID: 18647872
6.  Epidemiology of male same-sex behaviour and associated sexual health indicators in low- and middle-income countries: 2003–2007 estimates 
Sexually Transmitted Infections  2008;84(Suppl_1):i49-i56.
To conduct a systematic review of published and unpublished data from research and public health information systems on the prevalence of male-to-male sex in the total male population; as well as among men who have sex with men (MSM), data on prevalence of heterosexual activity and heterosexual unions; prevalence of condom use with male and female partners; and prevalence of HIV infection and other sexually transmitted infections (STIs).
Key indicators were defined (a) among men in the general population: prevalence of sex with a man ever and last year; (b) among MSM: prevalence of heterosexual experiences ever and last year; proportion of male-female transgenders; proportion of sex workers; prevalence of HIV and other STIs, condom use in last sexual encounter; consistent condom use with men last year; never used a condom with a man. With help from key informants, study searches were conducted in Pubmed, LILLACS, institutional databases, conference records and other sources. Methodology and quality of information were assessed, and the best data available for 2003–7 were selected. Indicator estimates from each study were used to propose regional estimate ranges.
A total of 83 new entries were entered into the database in addition to the previous 561, totalling 644. Of these, 107 showing 2003–7 data were selected. Many new studies came from sub-Saharan Africa, portraying hidden HIV epidemics among MSM. The most frequently reported estimate was HIV infection, with high estimate ranges in most of the regions, except for Middle East and North Africa and Eastern Europe. The next most frequently reported was lifetime frequency of heterosexual sex, showing that roughly 50% of MSM ever had sex with a woman. The small number of newer studies reporting prevalence of “sex with a man in last 12 months” between 2003 and 2007, did not warrant enough new evidence to revise our 2005 size estimates for MSM populations.
A considerable number of new studies with estimates of relevance to understanding sexual behaviour and HIV among MSM were identified, with an encouraging amount of new data coming from sub-Saharan Africa. However, limitations in the quality, utility and comparability of available information persist. At least three measures could be promoted for use in surveillance and academic studies: standardised indicators for MSM studies; standardised operational definitions of, and instructions to describe, variables; and standardised research designs and data gathering strategies. A prerequisite for this all is intense advocacy to ensure a social climate in which research into such matters is prioritised, resources are made available as needed and the human rights of MSM are respected.
PMCID: PMC2569188  PMID: 18647866

Results 1-6 (6)