PubMed Health⌕ Search

Biomedical subjects

R Lyerla

Publications and source records attributed to R Lyerla.

12 recordsLinked to original sources

Estimating the number of men who have sex with men in low and middle income countries.

OBJECTIVES: To collect and analyse published and unpublished surveillance and research data on the prevalence of same sex sexual activity among male adults (including male-to-female transgenders and sex workers) in low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. METHODS: 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. RESULTS: 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%. CONCLUSIONS: 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.

Adult↗

Estimates of the number of female sex workers in different regions of the world.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Adult↗

The 2005 Workbook: an improved tool for estimating HIV prevalence in countries with low level and concentrated epidemics.

OBJECTIVE: 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. METHODS: The structure of the software used to make estimates is briefly described, with particular attention to changes and improvements. DISCUSSION: 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.

Adult↗

Clients of sex workers in different regions of the world: hard to count.

OBJECTIVES: To estimate the proportion of the male population that reports having paid for sex in different regions. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Adolescent↗

Epidemiology of epidemic diphtheria in three regions, Russia, 1994-1996.

BACKGROUND: A massive diphtheria epidemic which began in the former Soviet Union in 1990 is the first large-scale diphtheria epidemic in developed countries in more than 30 years and has primarily affected adults. In response, health authorities attempted to maximize vaccination for children and conducted an unprecedented campaign to vaccinate adults. METHODS: We analyzed diphtheria surveillance data (case report forms and diphtheria vaccine coverage data) from three Russian regions from January 1994 to December 1996 and estimated vaccine effectiveness by the screening method. RESULTS: We reviewed records from 2243 (97.2%) of 2307 reported cases. The highest cumulative incidence in the period was among children aged 5 to 9 years (106 cases per 100,000 population); adults aged 40-49 years had the highest adult incidence for disease (88 cases per 100,000) and the highest incidence of any age group of clinically severe disease (29 cases per 100,000) and death (5.1 deaths per 100,000). The incidence among women aged 2049 years (82 per 100,000 women) was higher than among men (47 per 100,000, p<0.01). The annual incidence decreased from 25.2 cases per 100,000 population in 1994 to 9.4 cases per 100,000 in 1996. The decrease occurred as adult coverage increased from an estimated 25-30% in December 1992 to 88% in December 1995. Vaccine effectiveness was high among both children and adults. CONCLUSIONS: The Russian diphtheria epidemic primarily affected adults, especially women; this pattern is likely representative of diphtheria epidemics in immunized populations. Raising childhood immunization coverage and mass adult vaccination was effective in controlling the Russian epidemic. An improved understanding of the current epidemiology of diphtheria will be useful to design public health responses to prevent or control modern epidemics.

Adolescent↗

Beyond performance enhancement: polypharmacy among collegiate users of steroids.

The extremely low prevalence of steroid use among college students makes it virtually impossible to conduct analyses on any single college campus. By studying a cohort of 58,625 college students from 78 institutions that administered the Core Alcohol and Drug Survey in 1990 and 1991, a critical mass of 175 users on which it was possible to conduct statistical analyses was identified. Compared with a randomly selected group of nonusers, the steroid users reported consuming dramatically more alcohol and demonstrated higher rates of binge drinking. In addition, a significantly higher percentage of steroid users reported using tobacco, marijuana, cocaine, amphetamines, sedatives, hallucinogens, opiates, inhalants, and designer drugs. A higher percentage of steroid users than nonusers also reported experiencing negative consequences as a result of substance abuse, and a greater percentage of the steroid users reported family histories of abuse of alcohol and other drugs. Implications from the standpoint of student development are discussed.

Adult↗

Development of the Core Alcohol and Drug Survey: initial findings and future directions.

To assist universities in obtaining accurate information about the effectiveness of their efforts to prevent substance abuse, a committee of grantees of the US Department of Education's Fund for the Improvement of Postsecondary Education (FIPSE) developed an assessment tool known as the Core Alcohol and Drug Survey. This self-report instrument is designed to examine the nature, scope, and consequences of the use of alcohol and other drugs among college students. To date, the survey has been administered to nearly half a million students on 800 campuses, and the findings have been aggregated to create what is presently the largest national database on substance use in the higher education setting. The Core survey has often been used by campus health service personnel in assessment and programming efforts. This article describes the development and administration of the Core Alcohol and Drug Survey and provides a sampling of findings from the 1989-1991 FIPSE drug prevention group. This cohort included 58,625 students who completed the survey. Findings regarding consumption patterns, consequences of use, underage drinking, and regional differences are delineated, along with information regarding the future direction of Core survey projects.

Adult↗

A dengue outbreak among camp participants in a Caribbean island, 1995.

BACKGROUND: Dengue, a mosquito-transmitted viral disease, is a risk for visitors in tropical and subtropical areas. Several participants in a community-assistance program in Tortola, British Virgin Islands, in August, 1995, reported dengue-like symptoms either before or soon after leaving the island. METHODS: We conducted a retrospective cohort study to determine the extent of the outbreak, risk factors for illness, and the proportion of inapparent infections. Program participants were interviewed by telephone or mail, and asked to submit a serum sample for dengue diagnosis. A clinically-diagnosed case of dengue was defined as a person with fever and two or more of the following: headache, retro-orbital pain, myalgia, arthralgia, rash, or hemorrhagic manifestations. Serum specimens were tested for virus isolation, polymerase chain reaction (PCR), plaque-reduction neutralization (PRNT) or anti-dengue IgM and IgG antibody. RESULTS: Thirty-two (97%) of the 33 program participants responded; 21 of the 32 (66%) provided at least one serum sample for study. The median age was 17 years; 20 (62%) were women. Of 32 respondents, 22 (69%) met the clinical case definition for dengue: 15 of them (68%) had a positive IgM antibody response and 7 did not submit a serum sample. Dengue 1 virus (DEN-1) was identified by PCR in one case and all 11 positive PRNT results. No asymptomatic infections were identified. No respondent used effective mosquito repellent, and only 2 (6%) used bednets. CONCLUSIONS: A DEN-1 outbreak with a high attack rate (69%) occurred in a group of young short-term community aid workers. There were no asymptomatic infections documented. Participants' rare use of bednets or effective mosquito repellent highlights the importance of providing travelers to tropical areas with information about dengue fever and the recommended precautions to protect against infection.

Adolescent↗