Country-level Prevalence Research Articles

Global associations between UV dose exposure and current eczema prevalence in children and adolescents

Introduction: Environmental factors play an important role in the development and course of eczema during childhood. However, the role of ultraviolet (UV) exposure and other climatic factors has only been considered in a few studies thus far and never on a global scale. This study therefore examined between- and within-country associations between UV dose exposure measures and current eczema prevalences. Methods: Using questionnaire data collected in Phase Three of the International Study of Asthma and Allergies in Childhood, current eczema prevalence (itchy flexural rash in the past 12 months) among 13-14 year-olds was calculated for 218 centres in 91 countries, and among 6-7 year-olds, for 133 centres in 58 countries. Associations between current eczema prevalence and the mean, maximum, minimum, standard deviation and range of monthly UV dose exposures were assessed using linear mixed-effects regression models adjusted for gross national income, population density, climate type and mean monthly temperature and vapour pressure. The mean percent change in prevalence per 100 children (with 95% confidence intervals) per interquartile range increase in exposure is reported. Results: For the 13-14 year age-group centers, the country-level eczema prevalence (per 100 children) was positively associated with country-level monthly mean (0.74 [0.24; 1.25] per 2.3 kJ/m2), maximum (0.29 [0.02; 0.52] per 1.5 kJ/m2) and minimum (0.62 [0.22; 0.90] per 2.6 kJ/m2) UV dose exposure, and negatively associated with the standard deviation (-0.12 [-0.19; -0.03] per 0.6 kJ/m2) and range (-0.11 [-0.20; -0.04] per 1.5 kJ/m2) of monthly UV dose exposure. These trends were similar but attenuated and non-significant for the fewer 6-7 year age-group centers. No consistent within-country associations were observed across the two age groups. Conclusions: Several between-country associations for UV dose exposure and current eczema prevalence were observed, independently of climatic factors.

Early Childhood Developmental Status in Low- and Middle-Income Countries: National, Regional, and Global Prevalence Estimates Using Predictive Modeling.

BackgroundThe development of cognitive and socioemotional skills early in life influences later health and well-being. Existing estimates of unmet developmental potential in low- and middle-income countries (LMICs) are based on either measures of physical growth or proxy measures such as poverty. In this paper we aim to directly estimate the number of children in LMICs who would be reported by their caregivers to show low cognitive and/or socioemotional development.Methods and FindingsThe present paper uses Early Childhood Development Index (ECDI) data collected between 2005 and 2015 from 99,222 3- and 4-y-old children living in 35 LMICs as part of the Multiple Indicator Cluster Survey (MICS) and Demographic and Health Surveys (DHS) programs. First, we estimate the prevalence of low cognitive and/or socioemotional ECDI scores within our MICS/DHS sample. Next, we test a series of ordinary least squares regression models predicting low ECDI scores across our MICS/DHS sample countries based on country-level data from the Human Development Index (HDI) and the Nutrition Impact Model Study. We use cross-validation to select the model with the best predictive validity. We then apply this model to all LMICs to generate country-level estimates of the prevalence of low ECDI scores globally, as well as confidence intervals around these estimates.In the pooled MICS and DHS sample, 14.6% of children had low ECDI scores in the cognitive domain, 26.2% had low socioemotional scores, and 36.8% performed poorly in either or both domains. Country-level prevalence of low cognitive and/or socioemotional scores on the ECDI was best represented by a model using the HDI as a predictor. Applying this model to all LMICs, we estimate that 80.8 million children ages 3 and 4 y (95% CI 48.1 million, 113.6 million) in LMICs experienced low cognitive and/or socioemotional development in 2010, with the largest number of affected children in sub-Saharan Africa (29.4.1 million; 43.8% of children ages 3 and 4 y), followed by South Asia (27.7 million; 37.7%) and the East Asia and Pacific region (15.1 million; 25.9%). Positive associations were found between low development scores and stunting, poverty, male sex, rural residence, and lack of cognitive stimulation. Additional research using more detailed developmental assessments across a larger number of LMICs is needed to address the limitations of the present study.ConclusionsThe number of children globally failing to reach their developmental potential remains large. Additional research is needed to identify the specific causes of poor developmental outcomes in diverse settings, as well as potential context-specific interventions that might promote children’s early cognitive and socioemotional well-being.

Human rights protections and HIV prevalence among MSM who sell sex: Cross-country comparisons from a systematic review and meta-analysis

ABSTRACTLaws and policies can affect the HIV risk of key populations through a number of direct and indirect pathways. We investigated the association between HIV prevalence among men who engage in transactional sex and language in the penal code protecting sexual minorities, including men who have sex with men (MSM), and sex workers. HIV prevalence among men who engage in transactional sex was assessed through meta-analysis of published literature and country surveillance reports. Meta-regression was used to determine the association between HIV prevalence and protective laws for sexual minorities and sex workers. Sixty-six reports representing 28 countries and 31,924 individuals were included in the meta-analysis. Controlling for multiple study- and country-level variables, legal protection for sexual minorities was associated with a 10.9% (95% CI: 3.8–18.0%) and sex workers associated with a 7.0% (95% CI: 1.3–12.8%) decrease in country-level HIV prevalence among men who engage in transactional sex. Laws that seek to actively protect sex workers and MSM may be necessary to decrease HIV risk for this key population.

Estimations of worldwide prevalence of chronic hepatitis B virus infection: a systematic review of data published between 1965 and 2013

The quantification of the burden of disease attributable to hepatitis B virus (HBV) infection and the adaptation of prevention and control measures requires knowledge on its prevalence in the general population. For most countries such data are not routinely available. We estimated the national, regional, and global prevalence of chronic HBV infection. For this systematic review and pooled analysis, we searched for data on prevalence of chronic HBV infection published between Jan 1, 1965, and Oct 23, 2013, in the databases Medline, Embase, CAB Abstracts (Global health), Popline, and Web of Science. We included studies reporting the hepatitis B surface antigen (HBsAg) serological marker of chronic HBV infection in non-high-risk groups and extracted data into a customised database. For each country, we calculated HBsAg prevalence estimates and 95% CIs weighted by study size. We extrapolated prevalence estimates to population sizes in 2010 to obtain the number of individuals with chronic HBV infection. Of the 17,029 records screened, 1800 report on the prevalence of HBsAg covering 161 countries were included. HBsAg seroprevalence was 3·61% (95% CI 3·61-3·61) worldwide with highest endemicity in countries of the African region (total 8·83%, 8·82-8·83) and Western Pacific region (total 5·26%, 5·26-5·26). Within WHO regions, prevalence ranged from 0·20% (0·19-0·21; Mexico) to 13·55% (9·00-19·89; Haiti) in the Americas, to 0·48% (0·12-1·90; the Seychelles) to 22·38% (20·10-24·83; South Sudan) in the African region. We estimated that in 2010, globally, about 248 million individuals were HBsAg positive. This first global assessment of country-level population prevalence of chronic HBV infection found a wide variation between countries and highlights the need for continued prevention and control strategies and the collection of reliable epidemiologic data using standardised methodology. World Health Organization.

Prevalence and Social Determinants of Smoking in 15 Countries from North Africa, Central and Western Asia, Latin America and Caribbean: Secondary Data Analyses of Demographic and Health Surveys.

BackgroundArticle 20 of the World Health Organisation Framework Convention on Tobacco Control calls for a cross-country surveillance of tobacco use through population-based surveys. We aimed to provide country-level prevalence estimates for current smoking and current smokeless tobacco use and to assess social determinants of smoking.MethodsData from Demographic and Health Surveys done between 2005 and 2012, among men and women from nine North African, Central and West Asian countries and six Latin American and Caribbean countries were analyzed. Weighted country-level prevalence rates were estimated for ‘current smoking’ and ‘current use of smokeless tobacco (SLT) products’ among men and women. In each country, social determinants of smoking among men and women were assessed by binary logistic regression analyses by including men's and women's sampling weights to account for the complex survey design.FindingsPrevalence of smoking among men was higher than 40% in Armenia (63.1%), Moldova (51.1%), Ukraine (52%), Azerbaijan (49.8 %), Kyrgyz Republic (44.3 %) and Albania (42.52%) but the prevalence of smoking among women was less than 10% in most countries except Ukraine (14.81%) and Jordan (17.96%). The prevalence of smokeless tobacco use among men and women was less than 5% in all countries except among men in the Kyrgyz Republic (10.6 %). Smoking was associated with older age, lower education and poverty among men and higher education and higher wealth among women. Smoking among both men and women was associated with unskilled work, living in urban areas and being single.ConclusionSmoking among men was very high in Central and West Asian countries. Social pattern of smoking among women that was different from men in education and wealth should be considered while formulating tobacco control policies in some Central and West Asian countries.

Prevalence, distribution, and social determinants of tobacco use in 30 sub-Saharan African countries.

BackgroundAlthough the Framework Convention on Tobacco Control prioritizes monitoring of tobacco use by population-based surveys, information about the prevalence and patterns of tobacco use in sub-Saharan Africa is limited. We provide country-level prevalence estimates for smoking and smokeless tobacco (SLT) use and assess their social determinants.MethodsWe analyzed population-based data of the most recent Demographic Health Surveys performed between 2006 and 2013 involving men and women in 30 sub-Saharan African countries. Weighted country-level prevalence rates were estimated for ‘current smoking’ (cigarettes, pipe, cigars, etc.) and ‘current SLT use’ (chewing, snuff, etc.). From the pooled datasets for men and women, social determinants of smoking and SLT use were assessed through multivariate analyses using a dummy country variable as a control and by including a within-country sample weight for each country.ResultsAmong men, smoking prevalence rates were high in Sierra Leone (37.7%), Lesotho (34.1%), and Madagascar (28.5%); low (<10%) in Ethiopia, Benin, Ghana, Nigeria, and Sao Tome & Principe; the prevalence of SLT use was <10% in all countries except for Madagascar (24.7%) and Mozambique (10.9%). Among women, smoking and SLT prevalence rates were <5% in most countries except for Burundi (9.9%), Sierra Leone (6%), and Namibia (5.9%) (smoking), and Madagascar (19.6%) and Lesotho (9.1%) (SLT use). The proportion of females who smoked was lower than SLT users in most countries. Older age was strongly associated with both smoking and SLT use among men and women. Smoking among both men and women was weakly associated, but SLT use was strongly associated, with education. Similarly, smoking among men and women was weakly associated, but SLT use was strongly associated, with the wealth index. Smoking and SLT use were also associated with marital status among both men and women, as well as with occupation (agriculturists and unskilled workers).ConclusionsPrevalence of smoking among women was much lower than in men, although the social patterns of tobacco use were similar to those in men. Tobacco control strategies should target the poor, not/least educated, and agricultural and unskilled workers, who are the most vulnerable social groups in sub-Saharan Africa.

Smoking and smokeless tobacco use in nine South and Southeast Asian countries: prevalence estimates and social determinants from Demographic and Health Surveys.

BackgroundIn South and Southeast Asian countries, tobacco is consumed in diverse forms, and smoking among women is very low. We aimed to provide national estimates of prevalence and social determinants of smoking and smokeless tobacco use among men and women separately.MethodsData from Demographic and Health Surveys completed in nine countries (India, Pakistan, Nepal, Bangladesh, Maldives, Philippines, Cambodia, Indonesia, and Timor Leste) were analyzed. Current smoking or smokeless tobacco use was assessed as response “yes” to one or more of three questions, such as “Do you currently smoke cigarettes?” Weighted country-level prevalence rates for socio-economic subgroups were calculated for smoking and smokeless tobacco use. Binary logistic regression analyses were done on STATA/IC (version 10) by ‘svy’ command.ResultsPrevalence and type of tobacco use among men and women varied across the countries and among socio-economic sub groups. Smoking prevalence was much lower in women than men in all countries. Smoking among men was very high in Indonesia, Maldives, and Bangladesh. Smokeless tobacco (mainly chewable) was used in diverse forms, particularly in India, among both men and women. Chewing tobacco was common in Nepal, Bangladesh, Maldives, and Cambodia. Both smoking and smokeless tobacco use were associated with higher age, lower education, and poverty, but their association with place of residence and marital status was not uniform between men and women across the countries.ConclusionPolicymakers should consider type of tobacco consumption and their differentials among various population subgroups to implement country-specific tobacco control policies and target the vulnerable groups. Smokeless tobacco use should also be prioritized in tobacco control efforts.

Body size perception and weight control in youth: 9-year international trends from 24 countries.

ObjectivesTo examine nine-year trends and relationships regarding misperceptions of body size and dieting for weight loss among adolescents from 24 countries, and explore the influence of country-level overweight prevalence.MethodsSocio-demographic characteristics, body size perception, and dieting for weight loss were assessed in the Health Behaviour in School-aged Children survey conducted in 24 countries cross-sectionally at three time points (2001/02, 2005/06, 2009/10). Logistic regression models examined change over time in overestimation of body size in non-overweight adolescents, underestimation of body size in overweight adolescents, dieting for weight loss in non-overweight and overweight adolescents, and relationships between body size perception and dieting. Analyses were stratified by weight status and sex. Covariates included country-level overweight prevalence, family affluence, and country level of development. Body mass index was only included in models examining dieting for weight loss.ResultsCountry-level overweight prevalence increased over time (11.6% to 14.7%). Compared to Time 1, overweight adolescents had greater odds of body size underestimation at Time 3 (OR=1.68 for girls, OR=1.10 for boys), while non-overweight adolescents had lower odds of body size overestimation at Time 3 (OR=0.87 for girls, OR=0.89 for boys). Controlling for country-level overweight prevalence attenuated these relationships. Compared to Time 1, overweight and non-overweight boys were 10% more likely to diet at Time 3, while overweight and non-overweight girls were 19% and 16%, respectively, less likely to diet at Time 3. Controlling for country-level overweight prevalence did not impact trends in dieting for weight loss. Additionally, the association of self-perceived overweight with increased odds of dieting diminished over time.ConclusionsBody size perceptions among adolescents may have changed over time concurrent with shifts in country-level body weight. However, controlling for country-level overweight prevalence did not impact trends in dieting for weight loss, suggesting a potentially stronger impact of social comparison on weight-related perceptions than on behavior.

Current drivers and geographic patterns of HIV in Lesotho: implications for treatment and prevention in Sub-Saharan Africa

BackgroundThe most severe HIV epidemics worldwide occur in Lesotho, Botswana and Swaziland. Here we focus on the Lesotho epidemic, which has received little attention. We determined the within-country heterogeneity in the severity of the epidemic, and identified the risk factors for HIV infection. We also determined whether circumcised men in Lesotho have had a decreased risk of HIV infection in comparison with uncircumcised men. We discuss the implications of our results for expanding treatment (current coverage is only 60%) and reducing transmission.MethodsWe used data from the 2009 Lesotho Demographic and Health Survey, a nationally representative survey of 3,849 women and 3,075 men in 9,391 households. We performed multivariate analysis to identify factors associated with HIV infection in the sexually active population and calculated age-adjusted odds ratios (aORs). We constructed cartographic country-level prevalence maps using geo-referenced data.ResultsHIV is hyperendemic in the general population. The average prevalence is 27% in women and 18% in men, but shows substantial geographic variation. Throughout the country prevalence is higher in urban centers (31% in women; 21% in men) than in rural areas (25% in women; 17% in men), but the vast majority of HIV-infected individuals live in rural areas. Notably, prevalence is extremely high in women (18%) and men (12%) with only one lifetime sex partner. Women with more partners have a greater risk of infection: aOR 2.3 (2 to 4 partners), aOR 4.4 (≥5 partners). A less substantial effect was found for men: aOR 1.4 (3 to 6 partners), aOR 1.8 (≥7 partner). Medical circumcision protected against infection (aOR 0.5), traditional circumcision did not (aOR 0.9). Less than 5% of men in Lesotho have been medically circumcised; approximately 50% have been circumcised using traditional methods.ConclusionsThere is a substantial need for treatment throughout Lesotho, particularly in rural areas where there is the greatest burden of disease. Interventions aimed at reducing the number of sex partners may only have a limited effect on reducing transmission. Substantially increasing levels of medical circumcision could be very effective in reducing transmission, but will be very difficult to achieve given the current high prevalence of traditional circumcision.

Exploring substance use normalization among adolescents: A multilevel study in 35 countries

The substance use normalization thesis predicts that adolescent substance users are less likely to report substance use risk factors in high than in low prevalence countries. This study tests whether national population-level alcohol, cigarette and cannabis prevalence rates moderate the strength of the relationship between individual level social and behavioral risk factors and individual level alcohol, cigarette and cannabis use. Data from 2009/2010 Health Behaviour in School-Aged Children Study (N = 68,045, age = 15) from 35 countries was analyzed using logistic Hierarchical Linear Modeling. As expected based on low cannabis prevalence rates in all countries studied, no evidence of normalization was found for recent cannabis use. Also in line with the normalization thesis, results show that for substance use that reaches above 40% in at least some of the countries studied (drunkenness, alcohol and cigarette use), adolescents who reported use are less likely to report social and behavioral risk factors in high prevalence countries than in low prevalence countries. However, support for the normalization thesis was only partial in that results show that in models where evidence for normalization was found, there are risk factors that predict substance use to an equal degree regardless of country level prevalence rates. The current research shows that the normalization thesis is a useful framework for understanding the contextual aspects of adolescent alcohol, tobacco, and cannabis use. The study has implications for drug prevention as it suggests that selective prevention efforts may be particularly useful in low prevalence countries where screening based on risk factors may usefully identify adolescents at most risk for developing drug use problems. This approach may be less useful in high prevalence countries where screening based on risk factors is less likely to satisfactorily identify those at risk for developing drug use problems.

Medical students' tobacco use and attitudes towards tobacco control

Despite their important roles as future doctors in tobacco cessation counselling, the high prevalence of tobacco use among medical students may hinder them from advocating tobacco control policies and providing cessation counselling. Promoting this role among medical students is especially important in low- and middle-income countries with high burdens of tobacco use but limited resources for cessation programmes. This study examined the associations between medical students' tobacco use and their attitudes towards tobacco control policies and the roles of health professionals in the provision of tobacco cessation advice. This cross-sectional study included data from the large multi-country dataset generated by the Global Health Professions Student Survey, 2005-2008 (n = 36,533 medical students). Thirteen binary dependent variables related to medical students' attitudes towards tobacco control policies and the health professional's role in cessation counselling were examined using random-effects logistic regression, with tobacco use status as the key explanatory variable. Covariates included gender, receipt of cessation training, country-level and gender-specific smoking prevalence, region, and country income group. Current tobacco use was consistently associated with less favourable attitudes towards tobacco control policy and cessation advice. Compared with never users, daily users were less likely to agree that the sale of tobacco products to adolescents should be banned (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.39-0.58) and that health professionals should routinely advise patients to quit smoking (OR = 0.48, 95% CI 0.41-0.52) or other forms of tobacco use (OR = 0.84, 95% CI 0.72-0.97). Daily users were less likely to agree that health professionals who smoke are less likely to advise patients to stop smoking (OR = 0.44, 95% CI 0.39-0.41). Medical schools may benefit from a thorough re-evaluation of the scope of tobacco cessation training in their curricula in order to support students in smoking cessation and to shape their attitudes towards tobacco control. Targeting medical students who are current tobacco users in tobacco control efforts may be beneficial, given the cost-effectiveness of providing cessation advice.

Macroenvironmental Factors Including GDP per Capita and Physical Activity in Europe

Socioeconomic inequalities in physical activity at the individual level are well reported. Whether inequalities in economic development and other macroenvironmental variables between countries are also related to physical activity at the country level is comparatively unstudied. We examined the relationship between country-level data on macroenvironmental factors (gross domestic product (GDP) per capita, public sector expenditure on health, percentage living in urban areas, and cars per 1000 population) with country-level physical activity prevalence obtained from previous pan-European studies. Studies that assessed leisuretime physical activity (n = 3 studies including 27 countries in adults, n = 2 studies including 28 countries in children) and total physical activity (n = 3 studies in adults including 16 countries) were analyzed separately as were studies among adults and children. Strong and consistent positive correlations were observed between country prevalence of leisure-time physical activity and country GDP per capita in adults (average r = 0.70; all studies, P G 0.05). In multivariate analysis, country prevalence of leisure-time physical activity among adults remained associated with country GDP per capita (two of three studies) but not urbanization or educational attainment. Among school-age populations, no association was found between country GDP per capita and country prevalence of leisure-time physical activity. In those studies that assessed total physical activity (which also includes occupational and transport physical activity), no association with country GDP per capita was observed. Clear differences in national leisure-time physical activity levels throughout Europe may be a consequence of economic development. Lack of economic development of some countries in Europe may make increasing leisure-time physical activity more difficult. Further examination of the link between country GDP per capita and national physical activity levels (across leisure-time, occupational, and transport-related domains) is warranted.

Determining Treatment Needs at Different Spatial Scales Using Geostatistical Model-Based Risk Estimates of Schistosomiasis

BackgroundAfter many years of neglect, schistosomiasis control is going to scale. The strategy of choice is preventive chemotherapy, that is the repeated large-scale administration of praziquantel (a safe and highly efficacious drug) to at-risk populations. The frequency of praziquantel administration is based on endemicity, which usually is defined by prevalence data summarized at an arbitrarily chosen administrative level.MethodologyFor an ensemble of 29 West and East African countries, we determined the annualized praziquantel treatment needs for the school-aged population, adhering to World Health Organization guidelines. Different administrative levels of prevalence aggregation were considered; country, province, district, and pixel level. Previously published results on spatially explicit schistosomiasis risk in the selected countries were employed to classify each area into distinct endemicity classes that govern the frequency of praziquantel administration.Principal FindingsEstimates of infection prevalence adjusted for the school-aged population in 2010 revealed that most countries are classified as moderately endemic for schistosomiasis (prevalence 10–50%), while four countries (i.e., Ghana, Liberia, Mozambique, and Sierra Leone) are highly endemic (>50%). Overall, 72.7 million annualized praziquantel treatments (50% confidence interval (CI): 68.8–100.7 million) are required for the school-aged population if country-level schistosomiasis prevalence estimates are considered, and 81.5 million treatments (50% CI: 67.3–107.5 million) if estimation is based on a more refined spatial scale at the provincial level.Conclusions/SignificancePraziquantel treatment needs may be over- or underestimated depending on the level of spatial aggregation. The distribution of schistosomiasis in Ethiopia, Liberia, Mauritania, Uganda, and Zambia is rather uniform, and hence country-level risk estimates are sufficient to calculate treatment needs. On the other hand, countries like Burkina Faso, Mali, Mozambique, Sudan, and Tanzania show large spatial heterogeneity in schistosomiasis risk, which should be taken into account for calculating treatment requirements.

Is Obesity at Individual and National Level Associated With Lower Age at Menarche? Evidence From 34 Countries in the Health Behaviour in School-aged Children Study

A unique standardized international data set from adolescent girls in 34 countries in Europe and North America participating in the Health Behaviour in School-aged Children Study (HBSC) is used to investigate the contribution of body mass index (BMI) at individual and country level to cross-national differences in age at menarche. Two independent nationally representative survey data sets from 15-year-olds (n = 27,878, in 34 countries, year = 2005/2006) and 11-year-olds (n = 18,101, in 29 countries, year = 2001/2002) were analyzed. The survey instrument is a self-report questionnaire. Median age at menarche and 95% confidence intervals (CIs) were estimated using Kaplan-Meier analysis. Hierarchical models were used to assess the relationship between BMI and age at menarche (months). "Country-level obesity" was measured by prevalence of overweight/obesity (%) in each country. Country-level median age at menarche ranged between 12 years and 5 months and 13 years and 5 months. Country-level prevalence of overweight among 15-year-old girls ranged from 4% to 28%. Age at menarche was inversely associated with individual BMI (unstandardized regression coefficient beta = -1.01; 95% CI, -1.09 to -.94) and country-level aggregate overweight at age 11 (unstandardized regression coefficient beta = -.25; 95% CI, -.43 to -.08). Individual- and country-level measures of BMI account for 40% of the country-level variance in age at menarche. The findings add to the evidence that obesity in childhood is a risk factor for early puberty in girls and accounts for much of the cross-national variation in age at menarche. Future HBSC surveys can track this relationship in the wake of the obesity "epidemic."

Coming Out of the Nkuta: Disclosure of Sexual Orientation Associated with Reduced Risk Behavior Among MSM in Cameroon

The situation of sexual minorities in Cameroon is a human rights issue (Alternatives Cameroun, Adefho, Human Rights Watch, IGLHRC, 2010; Alternatives Cameroun, IGLHRC, Center for Human Rights, Global Rights, 2010). In this country, homosexuality is not only subject to social rejection but is also punishable by prison sentences. Although local MSM organizations, supported by a few human rights organizations, are fighting against this situation, legislation shall shortly become harsher,passing from 5 to 15 years imprisonment. Studies and reports have shownthatMSMarevictimsofdiverse formsofphysicaland/or psychological violence (Gueboguo, 2006, 2008), such as blackmail using disclosure of sexual orientation as a threat. In Cameroon, HIV prevalence is estimated to be 5.3% in the general population (UNAIDS, 2009). Among the MSM population, high proportions of sexual risk practices have been documented (Henry et al., 2010). Although country-level prevalence data in MSM are unavailable, studies in neighboring countries have shown much higher prevalence in MSM than in the general population (Baral, Sifakis, Cleghorn, & Beyrer, 2007; Wade et al., 2005). Access to existing national prevention and care programs remains difficult for MSM in Cameroon. The national strategy to fight the HIV epidemic and provide sexual prevention messages is still almost uniquely directed at heterosexuals (Henry et al., 2010). Prevention actions for MSM are often left to the goodwill of local community-based organizations working in complex and hostile social, political, and sometimes legal environments, where few people are mobilized on the subject. The difficulty in disclosing one’s sexual orientation compounds these problems. Thecriminalizationofsame-sexrelationshipsandsocial rejection as outlined above emphasize the importance of researching sexual orientation disclosure in Cameroon. A greater understanding of factors associated with disclosure could help actors better respond to basic needs of MSM, including health issues. Data on sexual orientation disclosure were collected and analyzed as part of a study in 2008 (local CBO Alternatives Cameroun initiative supported by Coalition PLUS and AIDES) on a convenience sample of 168 MSM in Douala. Participation eligibility criteria were as follows: aged 18 or older, living in Douala for at least 6 months, and having had sexual intercourse with a man at least once during one’s life. Study participants were administered an 85-item questionnaire during face-to-face interviews with trained Alternatives-Cameroun members. The questions explored the following domains: sociodemographic charE. Henry (&) Coalition PLUS, Tour ESSOR, 14 rue Scandicci, 93500 Pantin, France e-mail: ehenry@coalitionplus.org

Sexual risk among orphaned adolescents: is country-level HIV prevalence an important factor?

Previous studies from sub-Saharan Africa have found that orphans experience increased sexual risk compared to non-orphans. We developed a theoretical framework for the investigation of determinants of HIV risk and used it to generate specific hypotheses regarding the effect of country-level HIV prevalence on the sexual risk experience of orphans. We expected that countries with high HIV prevalence would experience a higher prevalence of orphanhood. We further hypothesised that orphans in countries with high HIV prevalence would experience increased sexual risk, compared to non-orphans, due to pressure on the extended family network, which is primarily responsible for the care of orphans in sub-Saharan Africa, resulting in poorer standards of care and guidance. We used hierarchical logistic regression models to investigate this hypothesis using cross-sectional, Demographic and Health Survey data from 10 sub-Saharan African countries. We found that countries with high HIV prevalence did indeed have higher prevalence of orphanhood. We also found that, amongst female adolescents, maternal and double orphans were significantly more likely to have started sex than non-orphans in countries with high HIV prevalence but were not at increased risk in low HIV prevalence countries. This effect of country-level HIV prevalence on the sexual risk of orphans was not explained by household level factors such as wealth, overcrowding or age of the household head. The same pattern of risk was not observed for male adolescents – male orphans were not more likely to have started sex than non-orphans. This suggests that orphaned adolescent women are an important target group for HIV prevention and that efforts should be made to integrate prevention messages into existing support programmes for orphans and vulnerable children.

The global prevalence of glucose-6-phosphate dehydrogenase deficiency: A systematic review and meta-analysis

Glucose-6-phosphate deficiency is the most prevalent enzyme deficiency, with an estimated 400 million people affected worldwide. This inherited deficiency causes neonatal hyperbilirubinemia and chronic hemolytic anemia. Although most affected individuals are asymptomatic, exposure to oxidative stressors such as certain drugs or infection, can elicit acute hemolysis. To characterize the global prevalence of G6PD deficiency, we conducted a systematic review of the G6PD deficiency literature, drawing studies from various databases, including MEDLINE/Pubmed and Biosis. Selected studies included cross-sectional and longitudinal studies published between 1960 and 2008. Additionally, meta-analytic procedures were employed to assess the degree of heterogeneity amongst prevalence estimates and, where appropriate, pool them. The searches yielded a total of 280 prevalence estimates, corresponding to 88 countries. The highest prevalence rates were reported among Sub-Saharan African countries, even after adjusting for assessment method. Meta-analysis revealed a high degree of heterogeneity for regional and global prevalence estimates. This heterogeneity in reported estimates appeared to be due to differences in G6PD deficiency assessment and diagnostic procedures. The magnitude and variation in global, regional, and country-level prevalence rates of G6PD deficiency are of public health import, particularly in planning programs to improve neonatal health and in the distribution of various medications, especially antimalarial drugs, as G6PD deficiency is most prevalent in malaria-endemic areas.

Characterizing the Global Prevalence of Glucose-6-Phosphate Dehydrogenase Deficiency

Glucose-6-phosphate deficiency is the most prevalent enzyme deficiency with an estimated 400 million people affected worldwide. This inherited deficiency causes neonatal hyperbilirubinemia, and chronic hemolytic anemia. Although most affected individuals are asymptomatic, exposure to oxidative stressors such as certain drugs or infection, can elicit acute hemolysis. The purpose of this study was to characterize the global prevalence of G6PD deficiency. We conducted a systematic review of the G6PD deficiency literature, drawing studies from various databases, including MEDLINE/Pubmed and Biosis. Selected studies included cross-sectional and longitudinal studies published between 1996 and 2006. Additionally, meta-analytic procedures were employed to assess the degree of heterogeneity amongst studies and, where appropriate, obtain pooled prevalence estimates. The database searches yielded a total of 93 country-level prevalence estimates, corresponding to 76 studies. The highest prevalence rates were reported among Sub-Saharan African countries, with prevalence ranging from 13% to 28%. Among countries in the Middle East and Asia, the prevalence ranged from 1% to 20%. In the Americas and Europe, the prevalence ranged between less than one and 12%. Meta-analysis revealed a degree of heterogeneity that precluded computation of pooled global and region-level prevalence estimates. This heterogeneity in reported estimates appeared to be due to differences in G6PD deficiency assessment procedures and the years in which the studies were conducted. This systematic review describes the global, regional, and country-level prevalence rates of G6PD deficiency. This information is of public health import, particularly in planning programs to improve neonatal health and in the distribution of various medications, especially antimalarial drugs since G6PD deficiency is most prevalent in malaria-endemic areas.