Chemical pollution assessment and prioritisation model for the Upper and Middle Vaal water management areas of South Africa.

A chemical pollution assessment and prioritisation model was developed for the Upper and Middle Vaal water management areas of South Africa in order to provide a simple and practical Pollution Index to assist with mitigation and rehabilitation activities. Historical data for 2003 to 2008 from 21 river sites were cubic-interpolated to daily values. Nine parameters were considered for this purpose, that is, ammonium, chloride, electrical conductivity, dissolved oxygen, pH, fluoride, nitrate, phosphate and sulphate. Parameter selection was based on sub-catchment pollution characteristics and availability of a consistent data range, against a harmonised guideline which provided five classes. Classes 1, 2, 3 and 4 used ideal catchment background values for Vaal Dam, Vaal Barrage, Blesbokspruit/Suikerbosrant and Klip Rivers, respectively. Class 5 represented values which fell above those for Klip River. The Pollution Index, as provided by the model, identified pollution prioritisation monitoring points on Rietspruit-W:K2, Natalspruit:K12, Blesbokspruit:B1, Rietspruit-L:R1/R2, Taaibosspruit:T1 and Leeuspruit:L1. Pre-classification indicated that pollution sources were domestic, industrial and mine effluent. It was concluded that rehabilitation and mitigation measures should prioritise points with high classes. Ability of the model to perform simple scenario building and analysis was considered to be an effective tool for acid mine drainage pollution assessment.

A genome-wide study reveals copy number variants exclusive to childhood obesity cases.

The prevalence of obesity in children and adults in the United States has increased dramatically over the past decade. Genomic copy number variations (CNVs) have been strongly implicated in subjects with extreme obesity and coexisting developmental delay. To complement these previous studies, we addressed CNVs in common childhood obesity by examining children with a BMI in the upper 5(th) percentile but excluding any subject greater than three standard deviations from the mean in order to reduce severe cases in the cohort. We performed a whole-genome CNV survey of our cohort of 1080 defined European American (EA) childhood obesity cases and 2500 lean controls (< 50(th) percentile BMI) who were genotyped with 550,000 SNP markers. Positive findings were evaluated in an independent African American (AA) cohort of 1479 childhood obesity cases and 1575 lean controls. We identified 17 CNV loci that were unique to at least three EA cases and were both previously unreported in the public domain and validated via quantitative PCR. Eight of these loci (47.1%) also replicated exclusively in AA cases (six deletions and two duplications). Replicated deletion loci consisted of EDIL3, S1PR5, FOXP2, TBCA, ABCB5, and ZPLD1, whereas replicated duplication loci consisted of KIF2B and ARL15. We also observed evidence for a deletion at the EPHA6-UNQ6114 locus when the AA cohort was investigated as a discovery set. Although these variants may be individually rare, our results indicate that CNVs contribute to the genetic susceptibility of common childhood obesity in subjects of both European and African ancestry.

Variants of DENND1B associated with asthma in children.

BACKGROUND: Asthma is a complex disease that has genetic and environmental causes. The genetic factors associated with susceptibility to asthma remain largely unknown. METHODS: We carried out a genomewide association study involving children with asthma. The sample included 793 North American children of European ancestry with persistent asthma who required daily inhaled glucocorticoid therapy and 1988 matched controls (the discovery set). We also tested for genomewide association in an independent cohort of 917 persons of European ancestry who had asthma and 1546 matched controls (the replication set). Finally, we tested for an association between 20 single-nucleotide polymorphisms (SNPs) at chromosome 1q31 and asthma in 1667 North American children of African ancestry who had asthma and 2045 ancestrally matched controls. RESULTS: In our meta-analysis of all samples from persons of European ancestry, we observed an association, with genomewide significance, between asthma and SNPs at the previously reported locus on 17q21 and an additional eight SNPs at a novel locus on 1q31. The SNP most strongly associated with asthma was rs2786098 (P=8.55x10(-9)). We observed replication of the association of asthma with SNP rs2786098 in the independent series of persons of European ancestry (combined P=9.3x10(-11)). The alternative allele of each of the eight SNPs on chromosome 1q31 was strongly associated with asthma in the children of African ancestry (P=1.6x10(-13) for the comparison across all samples). The 1q31 locus contains the 1q31 locus contains DENND1B, a gene expressed by natural killer cells and dendritic cells. DENND1B protein is predicted to interact with the tumor necrosis factor α receptor [corrected]. CONCLUSIONS: We have identified a locus containing DENND1B on chromosome 1q31.3 that is associated with susceptibility to asthma.

Rare recurrent copy number variations in metabotropic glutamate receptor interacting genes in children with neurodevelopmental disorders.

BACKGROUND: Neurodevelopmental disorders (NDDs), such as attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), are examples of complex and partially overlapping phenotypes that often lack definitive corroborating genetic information. ADHD and ASD have complex genetic associations implicated by rare recurrent copy number variations (CNVs). Both of these NDDs have been shown to share similar biological etiologies as well as genetic pleiotropy. METHODS: Platforms aimed at investigating genetic-based associations, such as high-density microarray technologies, have been groundbreaking techniques in the field of complex diseases, aimed at elucidating the underlying disease biology. Previous studies have uncovered CNVs associated with genes within shared candidate genomic networks, including glutamate receptor genes, across multiple different NDDs. To examine shared biological pathways across two of the most common NDDs, we investigated CNVs across 15,689 individuals with ADHD (n = 7920), ASD (n = 4318), or both (n = 3,416), as well as 19,993 controls. Cases and controls were matched by genotype array (i.e., Illumina array versions). Three case-control association studies each calculated and compared the observed vs. expected frequency of CNVs across individual genes, loci, pathways, and gene networks. Quality control measures of confidence in CNV-calling, prior to association analyses, included visual inspection of genotype and hybridization intensity. RESULTS: Here, we report results from CNV analysis in search for individual genes, loci, pathways, and gene networks. To extend our previous observations implicating a key role of the metabotropic glutamate receptor (mGluR) network in both ADHD and autism, we exhaustively queried patients with ASD and/or ADHD for CNVs associated with the 273 genomic regions of interest within the mGluR gene network (genes with one or two degrees protein-protein interaction with mGluR 1-8 genes). Among CNVs in mGluR network genes, we uncovered CNTN4 deletions enriched in NDD cases (P = 3.22E - 26, OR = 2.49). Additionally, we uncovered PRLHR deletions in 40 ADHD cases and 12 controls (P = 5.26E - 13, OR = 8.45) as well as clinically diagnostic relevant 22q11.2 duplications and 16p11.2 duplications in 23 ADHD + ASD cases and 9 controls (P = 4.08E - 13, OR = 15.05) and 22q11.2 duplications in 34 ADHD + ASD cases and 51 controls (P = 9.21E - 9, OR = 3.93); those control samples were not with previous 22qDS diagnosis in their EHR records. CONCLUSION: Together, these results suggest that disruption in neuronal cell-adhesion pathways confers significant risk to NDDs and showcase that rare recurrent CNVs in CNTN4, 22q11.2, and 16p11.2 are overrepresented in NDDs that constitute patients predominantly suffering from ADHD and ASD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02286817 First Posted: 10 November 14, ClinicalTrials.gov Identifier: NCT02777931 first posted: 19 May 2016, ClinicalTrials.gov Identifier: NCT03006367 first posted: 30 December 2016, ClinicalTrials.gov Identifier: NCT02895906 first posted: 12 September 2016.

High-resolution mapping and analysis of copy number variations in the human genome: a data resource for clinical and research applications.

We present a database of copy number variations (CNVs) detected in 2026 disease-free individuals, using high-density, SNP-based oligonucleotide microarrays. This large cohort, comprised mainly of Caucasians (65.2%) and African-Americans (34.2%), was analyzed for CNVs in a single study using a uniform array platform and computational process. We have catalogued and characterized 54,462 individual CNVs, 77.8% of which were identified in multiple unrelated individuals. These nonunique CNVs mapped to 3272 distinct regions of genomic variation spanning 5.9% of the genome; 51.5% of these were previously unreported, and >85% are rare. Our annotation and analysis confirmed and extended previously reported correlations between CNVs and several genomic features such as repetitive DNA elements, segmental duplications, and genes. We demonstrate the utility of this data set in distinguishing CNVs with pathologic significance from normal variants. Together, this analysis and annotation provides a useful resource to assist with the assessment of CNVs in the contexts of human variation, disease susceptibility, and clinical molecular diagnostics.

Raw water quality weight factors: Vaal basin, South Africa.

Weight factors (WFs) were developed for surface raw water pollution indicator variables in Vaal River's Upper and Middle Vaal sub-basins, in South Africa. The overall objective was to formulate a quantifiable ranking system to indicate importance of pollutant variables given their established effects on human and environmental health. Multi-criteria decision analysis (MCDA) was applied to qualitative data that were obtained from South Africa's target water quality ranges as well as from literature which represented expert opinion. The human and environmental health effect choice sets were ranked from 1 to 5 on nine pollutant variable criteria: NH3/NH4+, Cl-, conductivity (EC), dissolved oxygen (DO), pH, F-, NO3-/NO2-, PO4(3-) and SO4(2-). The weighted-sum method (WSM) then assigned highest and lowest normalised weights (NWs) to F- and Cl-, respectively, for human health effects (ɛhh) alternative. Highest and lowest NWs were assigned to NH3/NH4+ and EC, respectively, for environmental health effects (ɛeh) alternative. After aggregating the ɛhh and ɛeh WFs, resultant values ranked the variables from highest to lowest as follows: F->NO3-/NO2->/NH3/NH4+>DO>pH>SO4(2-)>PO4(3-)>EC>Cl-. The results represented the importance of variables given their established effects on human and environmental health. It was concluded that WFs provided a quantifiable barometer which could signal harmful exposure to elucidate negative effects of using polluted surface raw water in the study area. The values could be incorporated into water quality models like water quality indices. The approach could be used to develop WFs for other sites, taking into account issues like the site's pollution variables of concern as well as using a ranking key constructed from established literature.

The role of height-associated loci identified in genome wide association studies in the determination of pediatric stature.

BACKGROUND: Human height is considered highly heritable and correlated with certain disorders, such as type 2 diabetes and cancer. Despite environmental influences, genetic factors are known to play an important role in stature determination. A number of genetic determinants of adult height have already been established through genome wide association studies. METHODS: To examine 51 single nucleotide polymorphisms (SNPs) corresponding to the 46 previously reported genomic loci for height in 8,184 European American children with height measurements. We leveraged genotyping data from our ongoing GWA study of height variation in children in order to query the 51 SNPs in this pediatric cohort. RESULTS: Sixteen of these SNPs yielded at least nominally significant association to height, representing fifteen different loci including EFEMP1-PNPT1, GPR126, C6orf173, SPAG17, Histone class 1, HLA class III and GDF5-UQCC. Other loci revealed no evidence for association, including HMGA1 and HMGA2. For the 16 associated variants, the genotype score explained 1.64% of the total variation for height z-score. CONCLUSION: Among 46 loci that have been reported to associate with adult height to date, at least 15 also contribute to the determination of height in childhood.

Risk mapping of Rinderpest sero-prevalence in Central and Southern Somalia based on spatial and network risk factors.

BACKGROUND: In contrast to most pastoral systems, the Somali livestock production system is oriented towards domestic trade and export with seasonal movement patterns of herds/flocks in search of water and pasture and towards export points. Data from a rinderpest survey and other data sources have been integrated to explore the topology of a contact network of cattle herds based on a spatial proximity criterion and other attributes related to cattle herd dynamics. The objective of the study is to integrate spatial mobility and other attributes with GIS and network approaches in order to develop a predictive spatial model of presence of rinderpest. RESULTS: A spatial logistic regression model was fitted using data for 562 point locations. It includes three statistically significant continuous-scale variables that increase the risk of rinderpest: home range radius, herd density and clustering coefficient of the node of the network whose link was established if the sum of the home ranges of every pair of nodes was equal or greater than the shortest distance between the points. The sensitivity of the model is 85.1% and the specificity 84.6%, correctly classifying 84.7% of the observations. The spatial autocorrelation not accounted for by the model is negligible and visual assessment of a semivariogram of the residuals indicated that there was no undue amount of spatial autocorrelation. The predictive model was applied to a set of 6176 point locations covering the study area. Areas at high risk of having serological evidence of rinderpest are located mainly in the coastal districts of Lower and Middle Juba, the coastal area of Lower Shabele and in the regions of Middle Shabele and Bay. There are also isolated spots of high risk along the border with Kenya and the southern area of the border with Ethiopia. CONCLUSIONS: The identification of point locations and areas with high risk of presence of rinderpest and their spatial visualization as a risk map will be useful for informing the prioritization of disease surveillance and control activities for rinderpest in Somalia. The methodology applied here, involving spatial and network parameters, could also be applied to other diseases and/or species as part of a standardized approach for the design of risk-based surveillance activities in nomadic pastoral settings.

Mapping cattle trade routes in southern Somalia: a method for mobile livestock keeping systems.

The Somali economy is the only one in the world in which more than half the population is dependent on nomadic pastoralism. Trade typically involves drovers trekking animals over long distances to markets. A pilot approach for mapping trade routes was undertaken, using the Afmadow to Garissa routes in southern Somalia. The methodology included conducting a workshop with traders to gather preliminary information about the most-used routes and general husbandry practices and training selected drovers to collect data about key features along the routes, using hand-held global positioning system (GPS) devices, radio collar GPS and pictorial data forms. Collected data were then integrated into geographic information systems for analysis. The resultant spatial maps describe the Afmadow to Garissa routes, the speed of livestock movement along these routes and relevant environmental and social features affecting this speed. These data are useful for identifying critical control points for health screening along the routes, which may enable the establishment of a livestock certification system in nomadic pastoral environments.

Occupational noise-induced hearing loss among workers at Jomo Kenyatta International Airport, Nairobi.

BACKGROUND: Occupational noise induced hearing loss (NIHL) occurs among workers exposed to excessive amounts of noise for long durations. The average level of noise in some locations at Jomo Kenyatta International Airport (JKIA) was above the safe limit of 85dB hence workers were thought to be at risk. OBJECTIVE: To determine the occurrence and socio demographic attributes for NIHL at JKIA. DESIGN: Cross sectional descriptive study. SETTING: Jomo Kenyatta International Airport, Nairobi, Kenya. RESULTS: Mean age of respondents was 37 years with range 22 to 62, SD 8.98. Mean duration of exposure to noise was 10.7 years with range 1 to 40, SD 8.15. Prevalence of NIHL was 15.3%, with ground crew at 14.8% and air crew 16.1%. Ground crew had significantly poorer mean hearing threshold level at 3, 4 and 6 kHz than air crew (p = 0.015). Male workers were affected more than female counterparts with a male to female ratio of 4:3. 97% of those affected were non-managers, 3% managers while 68% of those affected resided in Embakasi Division close to the airport. Hearing threshold level at 4 kHz deteriorated with increasing age whereby those aged 50 years and above had a 13.7 times higher relative risk than those aged 20 to 29 years. Duration of exposure more than 10 years also had significantly higher risk (p < 0.01) for hearing loss at 4 kHz. CONCLUSION: Occupational noise induced hearing loss occurs atJKIA and that ground crew and older workers are more vulnerable. We recommend that prevention programmes be put in place.

A genome-wide association study identifies a locus for nonsyndromic cleft lip with or without cleft palate on 8q24.

OBJECTIVE: To identify, in a non-hypothesis manner, novel genetic factors associated with nonsyndromic cleft lip with or without cleft palate (NSCL/P). STUDY DESIGN: We performed a genome-wide association study in a pediatric cohort of European decent consisting of 111 NSCL/P cases and 5951 control subjects. All subjects were consecutively recruited from the Greater Philadelphia area from 2006 to 2009. High throughput genome-wide single nucleotide polymorphism genotyping was carried out with the Illumina Infinium II HumanHap550 BeadChip technology. RESULTS: We observed association at the genome-wide significance level with SNP rs987525 at a locus on 8q24, which harbors no characterized genes to date (P = 9.18 x 10(-8); odds ratio = 2.09, 95% confidence interval = 1.59 to 2.76). While searching for a replication cohort, the same genetic determinant was established through a genome-wide association study of NSCL/P in Germany, so this previous report acts as a de novo replication for our independent observation outlined here. CONCLUSIONS: These results strongly suggest that a locus on 8q24 is involved in the pathogenesis of NSCL/P.

Association of variants of the interleukin-23 receptor gene with susceptibility to pediatric Crohn's disease.

BACKGROUND & AIMS: Recently an association was shown between the single nucleotide polymorphism (SNP), rs11209026, within the interleukin-23 receptor (IL23R) locus and Crohn's disease (CD) as a consequence of a genome-wide association study of this disease in adults. We examined the effects of this and other previously reported SNPs at this locus with respect to CD in children. METHODS: By using data from our ongoing genome-wide association study in our cohort of 142 pediatric CD patients and 281 matched controls, we investigated the association of the previously reported SNPs at the IL23R locus with the childhood form of this disease. RESULTS: By using the Fisher exact test, the minor allele frequency of rs11209026 in the patients was 1.75%, whereas it was 6.61% in the controls, yielding a protective odds ratio (OR) of 0.25 (95% confidence interval, 0.10-0.65; 1-sided P = 9.2 x 10(-4)). Furthermore, of all the SNPs previously reported, rs11209026 was associated the most strongly. A subsequent family based association test (which is more resistant to population stratification) with 65 sets of trios derived from our initial patient cohort yielded significant association with rs11209026 in a transmission disequilibrium test (1-sided P = .0017). In contrast, no association was detected to the caspase-recruitment domain 15 gene for the inflammatory bowel disease phenotype. CONCLUSIONS: The OR of the IL23R variant in our pediatric study is highly comparable with that reported previously in a non-Jewish adult inflammatory bowel disease case-control cohort (OR, 0.26). As such, variants in the IL23R gene confer a similar magnitude of risk of CD to children as for their adult counterparts.

Contraceptive vaginal ring experiences among women and men in Kisumu, Kenya: A qualitative study.

BACKGROUND: Future HIV prevention options for women will likely include Antiretroviral (ARV)-based intravaginal rings. Valuable insights may be gained by examining user experiences with a similar licensed technology, a contraceptive ring, especially in settings where this technology may not be currently available. METHODS: In-depth interviews with 24 females enrolled in a trial assessing acceptability and use of a contraceptive ring, and 20 male sexual partners were conducted September 2014-April 2015. Elements of ethnography and phenomenological anthropology were used to collect, analyze, interpret, and describe ring users' experiences. Thematic analysis was completed in MaxQDA-10. RESULTS: Experiences with the contraceptive ring reflected a broader Family Planning (FP) paradigm that centered around three themes: latitudes and drawbacks of FP (being free); an FP method needs to be compatible with a woman's body (feeling normal); and dealing with fertility control uncertainties (how well does it really work). FP intentions and disclosure practices were influenced by partner support, socioeconomic factors, religion, cultural beliefs, and societal norms, including female sexuality. A user-friendly FP design was emphasized. Non-suppression of menstruation was favored by most. Unease with vaginal insertion as well as ring placement issues (slippage, expulsion) created initial challenges requiring clinician assistance and practice for some participants. While minor side-effects were described, concerns centered on ring efficacy, negative effect on a woman's sexual desire, and future fertility issues. CONCLUSIONS: Awareness of the multiple contexts in ring users' experience may inform the development, education, and promotion approaches for future ARV rings.

Validity of random blood glucose as a predictor of the quality of glycaemic control by glycated haemoglobin in out-patient diabetic patients at Kenyatta National Hospital.

BACKGROUND: Patients with diabetes mellitus in Kenya come to the hospital for follow-up visits very infrequently. For most of these patients their blood glucose monitoring is done only on the day of visit to the doctor. OBJECTIVE: To determine how well the physician-based morning random blood level determines or reflects the quality of glycaemic control. DESIGN: Cross-sectional study (morning, random blood glucose taken between 8.00 a.m. and 12.00 noon). SETTING: Out-patient diabetic clinic of Kenyatta National Hospital. SUBJECTS: Patients with diabetes mellitus either type 1 or type 2 attending the out-patient clinic. MAIN OUTCOME MEASURES: Random blood glucose (morning) and glycated haemoglobin (HbA1c). RESULTS: The morning random glucose level had a linear relationship with glycated haemoglobin levels taken simultaneously. A blood glucose level of 7 mmol/l had 92.7% sensitivity for good control (HbA1c < or = 7.8%) on a blood sample which was taken simultaneously and 59.8% specific for the same. When blood glucose cut-off level was raised to 10 mmol/l sensitivity fell to 66.3% for HbA1c < or = 7.8%, and 83.2% specificity for poor glycaemic control (HbA1c > 7.8%). There was marked fall in sensitivity of rising random blood glucose level in predicting good glycaemic control in our study, with concomitant rise in specificity of those high cut-off levels of blood glucose in predicting poor glycaemic control. CONCLUSION: Morning random blood glucose in the ambulatory diabetic patients related well to simultaneously assayed HbA1c. Blood glucose within usual therapeutic targets of 4-8 mmol/l predicted good glycaemic control (HbA1c < or = 7.8%) with high sensitivity at the range of 86.3-98.4%. In resource-poor settings, the morning random blood glucose assay, which is done in patients who may attend the diabetic clinic in the morning hours, may be used to predict the quality of their diabetic control. However caution should be exercised in its widespread use because its overall applicability may be clinic-specific depending largely on the average metabolic control of the diabetic population using that clinic. Further studies need to be done to relate HbA1c to blood glucose levels obtained at different times of the day in this population to determine the best predictor of good glycaemic control.

Nephropathy in patients with recently diagnosed type 2 diabetes mellitus in black Africans.

BACKGROUND: Albuminuria is long recognised as a sign of renal disease in diabetes. In type 1 diabetes, renal disease occurs after a longer duration of diabetic state. In type 2 diabetes, it is more variable. OBJECTIVE: To determine the prevalence and any risk factors of albuminuria in short-term (< or = 2 yrs) type 2 diabetes. DESIGN: Cross sectional, descriptive study. Microalbuminuria was assessed using micro II strips. SETTING: Outpatient diabetic clinic at Kenyatta National Hospital, Nairobi. SUBJECTS: Patients who were newly diagnosed or had had type 2 diabetes for two years or less. MAIN OUTCOME MEASURES: Microalbuminuria, lipids, glycated haemoglobin, fasting blood glucose and blood pressure. RESULTS: One hundred and thirty nine patients who had type 2 diabetes mellitus for < or = 2 yrs were seen, but only 100 patients were included in the study over a six month period. Their mean (SD) age was 53.7 (9.3) years. Mean (SD) duration of diabetes was 10.3 (7.5) months. Fifty per cent of the study patients were hypertensive. Only 48% had HbA1c < 8% while 36% had HbA1c > 9%. The lipid profile of total, LDL-HDL-cholesterol and triglycerides were predominantly within normal limits. Twenty six per cent were established to have albuminuria of which one patient had macroalbuminuria. Blood pressure, glycated haemoglobin and lipid parameters were not significantly different from patients without albuminuria CONCLUSION: Albuminuria occurred in a significant proportion of patients with short term type 2 diabetes. Comparable to studies done elsewhere on short-term type 2 diabetes, albuminuria is both a sign of nephropathy and a cardiovascular risk factor. It should be looked for in all patients with type 2 diabetes attending this clinic, even at diagnosis.

Evaluation of a proposed clinical case definition of paediatric acquired immune deficiency syndrome.

OBJECTIVE: To evaluate the proposed criteria against the laboratory parameters and to identify the clinical features with the highest predictive value in the diagnosis of paediatric AIDS. DESIGN: A cross sectional study. SETTING: Kenyatta National Hospital, Nairobi. RESULTS: More than twenty three per cent of the children studied were seropositive and 14% were diagnosed as having AIDS. Almost 70% of the children studied were below 24 months. AIDS was significantly associated with mouth lesions, both ulcers and oral candidiasis, skin lesions especially eczema and generalised pruritic dermatitis, prolonged cough, prolonged fever and generalised lymphadenopathy. The WHO criteria had a sensitivity of 60%, a specificity of 94%, positive predictive value of 60%, and negative predictive value of 94%. The Nairobi diagnostic criteria had a sensitivity of 80%, a specificity of 79%, a positive predictive value of 38% and a negative predictive value of 96%. CONCLUSION: The Nairobi Diagnostic Criteria are superior to the WHO criteria as a screening test due to their higher sensitivity, 80% against 60% for WHO.

Improvement of environmental health and hygiene practices--case study in the Northern Province.

The primary purpose of an improved water supply and sanitation is the achievement of acceptable health and hygiene standards as well as the sustainable improvement of the environment. Many governments recognize this and so they budget for large sums of money to improve these services to the communities. The purpose of this study was to investigate the different gaps in environmental health and hygiene practices with the aim of suggesting a strategy of improving this in the Northern Province of South Africa. To do this, 231 households and 30 schools were surveyed. Workshops and visits to different government departments were also used. This paper reports the results from this study which indicate that the situation in schools was not any better than that in households, with more than 90% of the villages still dependent on the unimproved pit latrines and 56,6% relying on standpipes which were (70% of the time) non-operational. The main problems identified seem to those associated with implementation and maintenance. The study concludes that with proper training of the water committees and their active involvement with the government and NGOs, environmental health and hygiene problems can be minimized or eliminated.

Persons at high risk for HIV infection in Kisumu, Kenya: identifying recruitment strategies for enrolment in HIV-prevention studies.

A combination of in-depth interviews (n = 38) and surveys (n = 203) were used to (1) identify strategies to recruit persons at high risk for HIV infection; (2) determine whether one strategy was more successful than others; and (3) describe motivators and barriers to participation in HIV-prevention studies. From in-depth interviews, four main recruitment strategies were identified: (1) use of a person with specific knowledge of a target population (link person mobilization); (2) use of co-workers or contemporaries (peer mobilization); (3) use of group or association leaders (leader mobilization); and (4) contacting persons by study staff directly (staff contact mobilization). The odds of inconsistently using condoms during sex were greater among those recruited using the peer mobilization (adjusted odds ratio [AOR] = 3.59; 95% confidence interval [CI] = 1.35-9.54) and the leader mobilization strategies (AOR = 2.76; 95% CI = 1.04-7.38) compared with the link person mobilization strategy. The main motivators for taking part in an HIV research study were receiving HIV-prevention education, HIV information or counselling, and receiving compensation for study participation. The main barriers were fear of lack of confidentiality and HIV testing concerns. Using evaluated strategies to recruit persons at high risk for HIV infection and addressing barriers to participation will improve the conduct and outcome of HIV-prevention studies.