Plasmodium vivax Prevalence in Semiarid Region of Northern Kenya, 2019.

In urban and rural areas of Turkana County, Kenya, we found that 2% of household members of patients with Plasmodium falciparum infections were infected with P. vivax. Enhanced surveillance of P. vivax and increased clinical resources are needed to inform control measures and identify and manage P. vivax infections.

The contribution of smoking and smokeless tobacco to oesophageal squamous cell carcinoma risk in the African oesophageal cancer corridor: Results from the ESCCAPE multicentre case-control studies.

Tobacco use is a well-established risk factor for oesophageal squamous cell carcinoma (ESCC) but the extent of its contribution to the disease burden in the African oesophageal cancer corridor has not been comprehensively elucidated, including by type of tobacco use. We investigated the contribution of tobacco use (smoking and smokeless) to ESCC in Tanzania, Malawi and Kenya. Hospital-based ESCC case-control studies were conducted in the three countries. Incident cases and controls were interviewed using a comprehensive questionnaire which included questions on tobacco smoking and smokeless tobacco use. Logistic regression models were used to estimate odds ratios (OR) and their 95% confidence intervals (CI) of ESCC associated with tobacco, adjusted for age, sex, alcohol use, religion, education and area of residence. One thousand two hundred seventy-nine cases and 1345 controls were recruited between August 5, 2013, and May 24, 2020. Ever-tobacco use was associated with increased ESCC risk in all countries: Tanzania (OR 3.09, 95%CI 1.83-5.23), and in Malawi (OR 2.45, 95%CI 1.80-3.33) and lesser in Kenya (OR 1.37, 95%CI 0.94-2.00). Exclusive smokeless tobacco use was positively associated with ESCC risk, in Tanzania, Malawi and Kenya combined (OR 1.92, 95%CI 1.26-2.92). ESCC risk increased with tobacco smoking intensity and duration of smoking. Tobacco use is an important risk factor of ESCC in Tanzania, Malawi and Kenya. Our study provides evidence that smoking and smokeless tobacco cessation are imperative in reducing ESCC risk.

An international report on bacterial communities in esophageal squamous cell carcinoma.

The incidence of esophageal squamous cell carcinoma (ESCC) is disproportionately high in the eastern corridor of Africa and parts of Asia. Emerging research has identified a potential association between poor oral health and ESCC. One possible link between poor oral health and ESCC involves the alteration of the microbiome. We performed an integrated analysis of four independent sequencing efforts of ESCC tumors from patients from high- and low-incidence regions of the world. Using whole genome sequencing (WGS) and RNA sequencing (RNAseq) of ESCC tumors from 61 patients in Tanzania, we identified a community of bacteria, including members of the genera Fusobacterium, Selenomonas, Prevotella, Streptococcus, Porphyromonas, Veillonella and Campylobacter, present at high abundance in ESCC tumors. We then characterized the microbiome of 238 ESCC tumor specimens collected in two additional independent sequencing efforts consisting of patients from other high-ESCC incidence regions (Tanzania, Malawi, Kenya, Iran, China). This analysis revealed similar ESCC-associated bacterial communities in these cancers. Because these genera are traditionally considered members of the oral microbiota, we next explored whether there was a relationship between the synchronous saliva and tumor microbiomes of ESCC patients in Tanzania. Comparative analyses revealed that paired saliva and tumor microbiomes were significantly similar with a specific enrichment of Fusobacterium and Prevotella in the tumor microbiome. Together, these data indicate that cancer-associated oral bacteria are associated with ESCC tumors at the time of diagnosis and support a model in which oral bacteria are present in high abundance in both saliva and tumors of some ESCC patients.

A very-hot food and beverage thermal exposure index and esophageal cancer risk in Malawi and Tanzania: findings from the ESCCAPE case-control studies.

BACKGROUND: Consumption of very-hot beverages/food is a probable carcinogen. In East Africa, we investigated esophageal squamous cell carcinoma (ESCC) risk in relation to four thermal exposure metrics separately and in a combined score. METHODS: From the ESCCAPE case-control studies in Blantyre, Malawi (2017-20) and Kilimanjaro, Tanzania (2015-19), we used logistic regression models adjusted for country, age, sex, alcohol and tobacco, to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for self-reported thermal exposures whilst consuming tea, coffee and/or porridge. RESULTS: The study included 849 cases and 906 controls. All metrics were positively associated with ESCC: temperature of drink/food (OR 1.92 (95% CI: 1.50, 2.46) for 'very hot' vs 'hot'), waiting time before drinking/eating (1.76 (1.37, 2.26) for <2 vs 2-5 minutes), consumption speed (2.23 (1.78, 2.79) for 'normal' vs 'slow') and mouth burning (1.90 (1.19, 3.01) for ≥6 burns per month vs none). Amongst consumers, the composite score ranged from 1 to 12, and ESCC risk increased with higher scores, reaching an OR of 4.6 (2.1, 10.0) for scores of ≥9 vs 3. CONCLUSIONS: Thermal exposure metrics were strongly associated with ESCC risk. Avoidance of very-hot food/beverage consumption may contribute to the prevention of ESCC in East Africa.

Geophagia and risk of squamous cell esophageal cancer in the African esophageal cancer corridor: Findings from the ESCCAPE multicountry case-control studies.

Geophagia, the intentional practice of consuming soil, occurs across the African esophageal cancer corridor, particularly during pregnancy. We investigated whether this practice is linked to endemic esophageal squamous cell carcinoma (ESCC) in this region. We conducted ESCC case-control studies in Tanzania, Malawi and Kenya. Cases were patients with incident histologically/clinically confirmed ESCC and controls were hospital patients/visitors without digestive diseases. Participants were asked if they had ever eaten soil (never/regularly/pregnancy-only). Odds ratios (OR) are adjusted for sex, age, tobacco, alcohol, country, religion and marital status. Overall, 934 cases (Malawi 535, Tanzania 304 and Kenya females 95) and 995 controls provided geophagia information. Among controls, ever-geophagia was common in women (Malawi 49%, Kenya 43% and Tanzania 29%) but not in men (10% Malawi, <1% Tanzania). In women, ESCC ORs were 1.25 (95% CI: 0.70, 2.22) for regular versus never geophagia and 0.88 (95% CI: 0.64, 1.22) for pregnancy-only versus never. Findings were stronger based on comparisons of cases with hospital visitor controls and were null using hospital patients as controls. In conclusion, geophagia is too rare to contribute to the male ESCC burden in Africa. In women, the practice is common but we did not find consistent evidence of a link to ESCC. The study cannot rule out selection bias masking modest effects. Physical effects of geophagia do not appear to have a large impact on overall ESCC risk. Research with improved constituent-based geophagia exposure assessment is needed.

Modeling approaches and performance for estimating personal exposure to household air pollution: A case study in Kenya.

This study assessed the performance of modeling approaches to estimate personal exposure in Kenyan homes where cooking fuel combustion contributes substantially to household air pollution (HAP). We measured emissions (PM2.5 , black carbon, CO); household air pollution (PM2.5 , CO); personal exposure (PM2.5 , CO); stove use; and behavioral, socioeconomic, and household environmental characteristics (eg, ventilation and kitchen volume). We then applied various modeling approaches: a single-zone model; indirect exposure models, which combine person-location and area-level measurements; and predictive statistical models, including standard linear regression and ensemble machine learning approaches based on a set of predictors such as fuel type, room volume, and others. The single-zone model was reasonably well-correlated with measured kitchen concentrations of PM2.5 (R2  = 0.45) and CO (R2  = 0.45), but lacked precision. The best performing regression model used a combination of survey-based data and physical measurements (R2  = 0.76) and a root mean-squared error of 85 µg/m3 , and the survey-only-based regression model was able to predict PM2.5 exposures with an R2 of 0.51. Of the machine learning algorithms evaluated, extreme gradient boosting performed best, with an R2 of 0.57 and RMSE of 98 µg/m3 .

Pay-as-you-go liquefied petroleum gas supports sustainable clean cooking in Kenyan informal urban settlement during COVID-19 lockdown.

Approximately 2.8 billion people rely on polluting fuels (e.g. wood, kerosene) for cooking. With affordability being a key access barrier to clean cooking fuels, such as liquefied petroleum gas (LPG), pay-as-you-go (PAYG) LPG smart meter technology may help resource-poor households adopt LPG by allowing incremental fuel payments. To understand the potential for PAYG LPG to facilitate clean cooking, objective evaluations of customers' cooking and spending patterns are needed. This study uses novel smart meter data collected between January 2018-June 2020, spanning COVID-19 lockdown, from 426 PAYG LPG customers living in an informal settlement in Nairobi, Kenya to evaluate stove usage (e.g. cooking events/day, cooking event length). Seven semi-structured interviews were conducted in August 2020 to provide context for potential changes in cooking behaviours during lockdown. Using stove monitoring data, objective comparisons of cooking patterns are made with households using purchased 6 kg cylinder LPG in peri-urban Eldoret, Kenya. In Nairobi, 95% of study households continued using PAYG LPG during COVID-19 lockdown, with consumption increasing from 0.97 to 1.22 kg/capita/month. Daily cooking event frequency also increased by 60% (1.07 to 1.72 events/day). In contrast, average days/month using LPG declined by 75% during lockdown (17 to four days) among seven households purchasing 6 kg cylinder LPG in Eldoret. Interviewed customers reported benefits of PAYG LPG beyond fuel affordability, including safety, time savings and cylinder delivery. In the first study assessing PAYG LPG cooking patterns, LPG use was sustained despite a COVID-19 lockdown, illustrating how PAYG smart meter technology may help foster clean cooking access.

Iodine status in western Kenya: a community-based cross-sectional survey of urinary and drinking water iodine concentrations.

Spot urinary iodine concentrations (UIC) are presented for 248 individuals from western Kenya with paired drinking water collected between 2016 and 2018. The median UIC was 271 µg L-1, ranging from 9 to 3146 µg L-1, unadjusted for hydration status/dilution. From these data, 12% were potentially iodine deficient (< 100 µg L-1), whilst 44% were considered to have an excess iodine intake (> 300 µg L-1). The application of hydration status/urinary dilution correction methods was evaluated for UICs, using creatinine, osmolality and specific gravity. The use of specific gravity correction for spot urine samples to account for hydration status/urinary dilution presents a practical approach for studies with limited budgets, rather than relying on unadjusted UICs, 24 h sampling, use of significantly large sample size in a cross-sectional study and other reported measures to smooth out the urinary dilution effect. Urinary corrections did influence boundary assessment for deficiency-sufficiency-excess for this group of participants, ranging from 31 to 44% having excess iodine intake, albeit for a study of this size. However, comparison of the correction methods did highlight that 22% of the variation in UICs was due to urinary dilution, highlighting the need for such correction, although creatinine performed poorly, yet specific gravity as a low-cost method was comparable to osmolality corrections as the often stated 'gold standard' metric for urinary concentration. Paired drinking water samples contained a median iodine concentration of 3.2 µg L-1 (0.2-304.1 µg L-1). A weak correlation was observed between UIC and water-I concentrations (R = 0.11).

Traditional and commercial alcohols and esophageal cancer risk in Kenya.

Squamous cell esophageal cancer is common throughout East Africa, but its etiology is poorly understood. We investigated the contribution of alcohol consumption to esophageal cancer in Kenya, based on a hospital-based case-control study conducted from 08/2013 to 03/2018 in Eldoret, western Kenya. Cases had an endoscopy-confirmed esophageal tumor whose histology did not rule out squamous cell carcinoma. Age and gender frequency-matched controls were recruited from hospital visitors/patients without digestive diseases. Logistic regression was used to calculate odds ratios (ORs) and their 95% confidence intervals (CI) adjusting for tobacco (type, intensity) and 6 other potential confounders. A total of 422 cases (65% male, mean at diagnosis 60 (SD 14) years) and 414 controls were included. ORs for ever-drinking were stronger in ever-tobacco users (9.0, 95% CI: 3.4, 23.8, with few tobacco users who were never drinkers) than in never-tobacco users (2.6, 95% CI: 1.6, 4.1). Risk increased linearly with number of drinks: OR for >6 compared to >0 to ≤2 drinks/day were 5.2 (2.4, 11.4) in ever-tobacco users and 2.1 (0.7, 4.4) in never-tobacco users. Although most ethanol came from low ethanol alcohols (busaa or beer), for the same ethanol intake, if a greater proportion came from the moonshine chang'aa, it was associated with a specific additional risk. The population attributable fraction for >2 drinks per day was 48% overall and highest in male tobacco users. Alcohol consumption, particularly of busaa and chang'aa, contributes to half of the esophageal cancer burden in western Kenya.

Dental fluorosis and oral health in the African Esophageal Cancer Corridor: Findings from the Kenya ESCCAPE case-control study and a pan-African perspective.

There are no studies of oral health in relation to esophageal cancer in Africa, or of Eastern Africa's endemic dental fluorosis, an irreversible enamel hypo-mineralization due to early-life excessive fluoride intake. During 2014-18, we conducted a case-control study of squamous cell esophageal cancer in Eldoret, western Kenya. Odds ratios (AORs (95% confidence intervals)) were adjusted for design factors, tobacco, alcohol, ethnicity, education, oral hygiene and missing/decayed teeth. Esophageal cancer cases (N = 430) had poorer oral health and hygiene than controls (N = 440). Compared to no dental fluorosis, moderate/severe fluorosis, which affected 44% of cases, had a crude OR of 20.8 (11.6, 37.4) and on full adjustment was associated with 9.4-fold (4.6, 19.1) increased risk, whilst mild fluorosis (43% of cases) had an AOR of 2.3 (1.3, 4.0). The prevalence of oral leukoplakia and tooth loss/decay increased with fluorosis severity, and increased cancer risks associated with moderate/severe fluorosis were particularly strong in individuals with more tooth loss/decay. Using a mswaki stick (AOR = 1.7 (1.0, 2.9)) rather than a commercial tooth brush and infrequent tooth brushing also independently increased risk. Geographic variations showed that areas of high esophageal cancer incidence and those of high groundwater fluoride levels have remarkably similar locations across Eastern Africa. In conclusion, poor oral health in combination with, or as a result of, high-altitude susceptibility to hydro-geologically influenced dental fluorosis may underlie the striking co-location of Africa's esophageal cancer corridor with the Rift Valley. The findings call for heightened research into primary prevention opportunities of this highly fatal but common cancer.

Hot beverages and oesophageal cancer risk in western Kenya: Findings from the ESCCAPE case-control study.

Oesophageal squamous cell carcinoma (ESCC) has markedly high incidence rates in Kenya and much of East Africa, with a dire prognosis and poorly understood aetiology. Consumption of hot beverages-a probable carcinogen to humans-is associated with increased ESCC risk in other settings and is habitually practiced in Kenya. We conducted a case-control study in Eldoret, western Kenya between August 2013 and March 2018. Cases were patients with endoscopically confirmed oesophageal cancer whose histology did not rule out ESCC. Age and sex-matched controls were hospital visitors and hospital out and in-patients excluding those with digestive diseases. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for self-reported drinking temperatures; consumption frequency; mouth burning frequency and hot porridge consumption using logistic regression models adjusted for potential confounders. Drinking temperature association with tumour sub-location was also investigated. The study included 430 cases and 440 controls. Drinkers of 'very hot' and 'hot' beverages (>95% tea) had a 3.7 (95% CI: 2.1-6.5) and 1.4-fold (1.0-2.0) ESCC risk, respectively compared to 'warm' drinkers. This trend was consistent in males, females, never and ever alcohol/tobacco and was stronger over than under age 50 years. The tumour sub-location distribution (upper/middle/lower oesophagus) did not differ by reported drinking temperature. Our study is the first comprehensive investigation in this setting to-date to observe a link between hot beverage consumption and ESCC in East Africa. These findings provide further evidence for the role of this potentially modifiable risk factor in ESCC aetiology.

Improving rational use of ACTs through diagnosis-dependent subsidies: Evidence from a cluster-randomized controlled trial in western Kenya.

BACKGROUND: More than half of artemisinin combination therapies (ACTs) consumed globally are dispensed in the retail sector, where diagnostic testing is uncommon, leading to overconsumption and poor targeting. In many malaria-endemic countries, ACTs sold over the counter are available at heavily subsidized prices, further contributing to their misuse. Inappropriate use of ACTs can have serious implications for the spread of drug resistance and leads to poor outcomes for nonmalaria patients treated with incorrect drugs. We evaluated the public health impact of an innovative strategy that targets ACT subsidies to confirmed malaria cases by coupling free diagnostic testing with a diagnosis-dependent ACT subsidy. METHODS AND FINDINGS: We conducted a cluster-randomized controlled trial in 32 community clusters in western Kenya (population approximately 160,000). Eligible clusters had retail outlets selling ACTs and existing community health worker (CHW) programs and were randomly assigned 1:1 to control and intervention arms. In intervention areas, CHWs were available in their villages to perform malaria rapid diagnostic tests (RDTs) on demand for any individual >1 year of age experiencing a malaria-like illness. Malaria RDT-positive individuals received a voucher for a discount on a quality-assured ACT, redeemable at a participating retail medicine outlet. In control areas, CHWs offered a standard package of health education, prevention, and referral services. We conducted 4 population-based surveys-at baseline, 6 months, 12 months, and 18 months-of a random sample of households with fever in the last 4 weeks to evaluate predefined, individual-level outcomes. The primary outcome was uptake of malaria diagnostic testing at 12 months. The main secondary outcome was rational ACT use, defined as the proportion of ACTs used by test-positive individuals. Analyses followed the intention-to-treat principle using generalized estimating equations (GEEs) to account for clustering with prespecified adjustment for gender, age, education, and wealth. All descriptive statistics and regressions were weighted to account for sampling design. Between July 2015 and May 2017, 32,404 participants were tested for malaria, and 10,870 vouchers were issued. A total of 7,416 randomly selected participants with recent fever from all 32 clusters were surveyed. The majority of recent fevers were in children under 18 years (62.9%, n = 4,653). The gender of enrolled participants was balanced in children (49.8%, n = 2,318 boys versus 50.2%, n = 2,335 girls), but more adult women were enrolled than men (78.0%, n = 2,139 versus 22.0%, n = 604). At baseline, 67.6% (n = 1,362) of participants took an ACT for their illness, and 40.3% (n = 810) of all participants took an ACT purchased from a retail outlet. At 12 months, 50.5% (n = 454) in the intervention arm and 43.4% (n = 389) in the control arm had a malaria diagnostic test for their recent fever (adjusted risk difference [RD] = 9 percentage points [pp]; 95% CI 2-15 pp; p = 0.015; adjusted risk ratio [RR] = 1.20; 95% CI 1.05-1.38; p = 0.015). By 18 months, the ARR had increased to 1.25 (95% CI 1.09-1.44; p = 0.005). Rational use of ACTs in the intervention area increased from 41.7% (n = 279) at baseline to 59.6% (n = 403) and was 40% higher in the intervention arm at 18 months (ARR 1.40; 95% CI 1.19-1.64; p < 0.001). While intervention effects increased between 12 and 18 months, we were not able to estimate longer-term impact of the intervention and could not independently evaluate the effects of the free testing and the voucher on uptake of testing. CONCLUSIONS: Diagnosis-dependent ACT subsidies and community-based interventions that include the private sector can have an important impact on diagnostic testing and population-wide rational use of ACTs. Targeting of the ACT subsidy itself to those with a positive malaria diagnostic test may also improve sustainability and reduce the cost of retail-sector ACT subsidies. TRIAL REGISTRATION: ClinicalTrials.gov NCT02461628.

Evaluation of malaria rapid diagnostic test (RDT) use by community health workers: a longitudinal study in western Kenya.

BACKGROUND: Malaria rapid diagnostic tests (RDTs) are a simple, point-of-care technology that can improve the diagnosis and subsequent treatment of malaria. They are an increasingly common diagnostic tool, but concerns remain about their use by community health workers (CHWs). These concerns regard the long-term trends relating to infection prevention measures, the interpretation of test results and adherence to treatment protocols. This study assessed whether CHWs maintained their competency at conducting RDTs over a 12-month timeframe, and if this competency varied with specific CHW characteristics. METHODS: From June to September, 2015, CHWs (n = 271) were trained to conduct RDTs using a 3-day validated curriculum and a baseline assessment was completed. Between June and August, 2016, CHWs (n = 105) were randomly selected and recruited for follow-up assessments using a 20-step checklist that classified steps as relating to safety, accuracy, and treatment; 103 CHWs participated in follow-up assessments. Poisson regressions were used to test for associations between error count data at follow-up and Poisson regression models fit using generalized estimating equations were used to compare data across time-points. RESULTS: At both baseline and follow-up observations, at least 80% of CHWs correctly completed 17 of the 20 steps. CHWs being 50 years of age or older was associated with increased total errors and safety errors at baseline and follow-up. At follow-up, prior experience conducting RDTs was associated with fewer errors. Performance, as it related to the correct completion of all checklist steps and safety steps, did not decline over the 12 months and performance of accuracy steps improved (mean error ratio: 0.51; 95% CI 0.40-0.63). Visual interpretation of RDT results yielded a CHW sensitivity of 92.0% and a specificity of 97.3% when compared to interpretation by the research team. None of the characteristics investigated was found to be significantly associated with RDT interpretation. CONCLUSIONS: With training, most CHWs performing RDTs maintain diagnostic testing competency over at least 12 months. CHWs generally perform RDTs safely and accurately interpret results. Younger age and prior experiences with RDTs were associated with better testing performance. Future research should investigate the mode by which CHW characteristics impact RDT procedures.

Bridging Income Generation with Group Integrated Care for cardiovascular risk reduction: Rationale and design of the BIGPIC study.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of mortality worldwide, with >80% of CVD deaths occurring in low and middle income countries (LMICs). Diabetes mellitus and pre-diabetes are risk factors for CVD, and CVD is the major cause of morbidity and mortality among individuals with DM. There is a critical period now during which reducing CVD risk among individuals with diabetes and pre-diabetes may have a major impact. Cost-effective, culturally appropriate, and context-specific approaches are required. Two promising strategies to improve health outcomes are group medical visits and microfinance. METHODS/DESIGN: This study tests whether group medical visits integrated into microfinance groups are effective and cost-effective in reducing CVD risk among individuals with diabetes or at increased risk for diabetes in western Kenya. An initial phase of qualitative inquiry will assess contextual factors, facilitators, and barriers that may impact integration of group medical visits and microfinance for CVD risk reduction. Subsequently, we will conduct a four-arm cluster randomized trial comparing: (1) usual clinical care, (2) usual clinical care plus microfinance groups only, (3) group medical visits only, and (4) group medical visits integrated into microfinance groups. The primary outcome measure will be 1-year change in systolic blood pressure, and a key secondary outcome measure is 1-year change in overall CVD risk as measured by the QRISK2 score. We will conduct mediation analysis to evaluate the influence of changes in social network characteristics on intervention outcomes, as well as moderation analysis to evaluate the influence of baseline social network characteristics on effectiveness of the interventions. Cost-effectiveness analysis will be conducted in terms of cost per unit change in systolic blood pressure, percent change in CVD risk score, and per disability-adjusted life year saved. DISCUSSION: This study will provide evidence regarding effectiveness and cost-effectiveness of interventions to reduce CVD risk. We aim to produce generalizable methods and results that can provide a model for adoption in low-resource settings worldwide.

Impact of Bridging Income Generation with Group Integrated Care (BIGPIC) on Hypertension and Diabetes in Rural Western Kenya.

BACKGROUND: Rural settings in Sub-Saharan Africa (SSA) consistently report low participation in non-communicable disease (NCD) treatment programs and poor outcomes. OBJECTIVE: The objective of this study is to assess the impact of the implementation of a patient-centered rural NCD care delivery model called Bridging Income Generation through grouP Integrated Care (BIGPIC). DESIGN: The study prospectively tracked participation and health outcomes for participants in a screening event and compared linkage frequencies to a historical comparison group. PARTICIPANTS: Rural Kenyan participants attending a voluntary NCD screening event were included within the BIGPIC model of care. INTERVENTIONS: The BIGPIC model utilizes a contextualized care delivery model designed to address the unique barriers faced in rural settings. This model emphasizes the following steps: (1) find patients in the community, (2) link to peer/microfinance groups, (3) integrate education, (4) treat in the community, (5) enhance economic sustainability and (6) generate demand for care through incentives. MAIN MEASURES: The primary outcome is the linkage frequency, which measures the percentage of patients who return for care after screening positive for either hypertension and/or diabetes. Secondary measures include retention frequencies defined as the percentage of patients remaining engaged in care throughout the 9-month follow-up period and changes in systolic (SBP) and diastolic blood pressure (DBP) and blood sugar over 12 months. KEY RESULTS: Of the 879 individuals who were screened, 14.2 % were confirmed to have hypertension, while only 1.4 % were confirmed to have diabetes. The implementation of a comprehensive microfinance-linked, community-based, group care model resulted in 72.4 % of screen-positive participants returning for subsequent care, of which 70.3 % remained in care through the 12 months of the evaluation period. Patients remaining in care demonstrated a statistically significant mean decline of 21 mmHg in SBP [95 % CI (13.9 to 28.4), P < 0.01] and 5 mmHg drop in DBP [95 % CI (1.4 to 7.6), P < 0.01]. CONCLUSIONS: The implementation of a contextualized care delivery model built around the unique needs of rural SSA participants led to statistically significant improvements in linkage to care and blood pressure reduction.

Household beliefs about malaria testing and treatment in Western Kenya: the role of health worker adherence to malaria test results.

BACKGROUND: Although use of malaria diagnostic tests has increased in recent years, health workers often prescribe anti-malarial drugs to individuals who test negative for malaria. This study investigates how health worker adherence to malaria case management guidelines influences individuals' beliefs about whether their illness was malaria, and their confidence in the effectiveness of artemisinin-based combination therapy (ACT). METHODS: A survey was conducted with 2065 households in Western Kenya about a household member's treatment actions for a recent febrile illness. The survey also elicited the individual's (or their caregiver's) beliefs about the illness and about malaria testing and treatment. Logistic regressions were used to test the association between these beliefs and whether the health worker adhered to malaria testing and treatment guidelines. RESULTS: Of the 1070 individuals who visited a formal health facility during their illness, 82% were tested for malaria. ACT rates for malaria-positive and negative individuals were 89 and 49%, respectively. Overall, 65% of individuals/caregivers believed that the illness was "very likely" malaria. Individuals/caregivers had higher odds of saying that the illness was "very likely" malaria when the individual was treated with ACT, and this was the case both among individuals not tested for malaria [adjusted odds ratio (AOR) 3.42, 95% confidence interval (CI) [1.65 7.10], P = 0.001] and among individuals tested for malaria, regardless of their test result. In addition, 72% of ACT-takers said the drug was "very likely" effective in treating malaria. However, malaria-negative individuals who were treated with ACT had lower odds of saying that the drugs were "very likely" effective than ACT-takers who were not tested or who tested positive for malaria (AOR 0.29, 95% CI [0.13 0.63], P = 0.002). CONCLUSION: Individuals/caregivers were more likely to believe that the illness was malaria when the patient was treated with ACT, regardless of their test result. Moreover, malaria-negative individuals treated with ACT had lower confidence in the drug than other individuals who took ACT. These results suggest that ensuring health worker adherence to malaria case management guidelines will not only improve ACT targeting, but may also increase patient/caregivers' confidence in malaria testing and treatment.

Barriers Influencing Linkage to Hypertension Care in Kenya: Qualitative Analysis from the LARK Hypertension Study.

BACKGROUND: Hypertension, the leading global risk factor for mortality, is characterized by low treatment and control rates in low- and middle-income countries. Poor linkage to hypertension care contributes to poor outcomes for patients. However, specific factors influencing linkage to hypertension care are not well known. OBJECTIVE: To evaluate factors influencing linkage to hypertension care in rural western Kenya. DESIGN: Qualitative research study using a modified Health Belief Model that incorporates the impact of emotional and environmental factors on behavior. PARTICIPANTS: Mabaraza (traditional community assembly) participants (n = 242) responded to an open invitation to residents in their respective communities. Focus groups, formed by purposive sampling, consisted of hypertensive individuals, at-large community members, and community health workers (n = 169). APPROACH: We performed content analysis of the transcripts with NVivo 10 software, using both deductive and inductive codes. We used a two-round Delphi method to rank the barriers identified in the content analysis. We selected factors using triangulation of frequency of codes and themes from the transcripts, in addition to the results of the Delphi exercise. Sociodemographic characteristics of participants were summarized using descriptive statistics. KEY RESULTS: We identified 27 barriers to linkage to hypertension care, grouped into individual (cognitive and emotional) and environmental factors. Cognitive factors included the asymptomatic nature of hypertension and limited information. Emotional factors included fear of being a burden to the family and fear of being screened for stigmatized diseases such as HIV. Environmental factors were divided into physical (e.g. distance), socioeconomic (e.g. poverty), and health system factors (e.g. popularity of alternative therapies). The Delphi results were generally consistent with the findings from the content analysis. CONCLUSIONS: Individual and environmental factors are barriers to linkage to hypertension care in rural western Kenya. Our analysis provides new insights and methodological approaches that may be relevant to other low-resource settings worldwide.

Development and validation of a rapid assessment tool for malaria prevention.

BACKGROUND: Insecticide-treated bed nets (ITN) have been shown to be efficacious in reducing malaria morbidity and mortality in many regions. Unfortunately in some areas, malaria has persisted despite the scale up of ITNs. Recent reports indicate that human behaviour and mosquito behaviour are potential threats to the efficacy of ITNs. However, these concerns are likely highly heterogeneous even at very small scales. This study aimed at developing, testing and validating a rapid assessment tool to collect actionable information at local levels for a quick evaluation of potential barriers to malaria prevention. METHODS: The study was conducted at the Webuye Health and Demographic Surveillance Site in Bungoma East Sub-County, Kenya. Based on the findings from the case-control study, 12 primary surveillance components that encompass the major impediments to successful prevention were identified and used to develop a rapid assessment tool. Twenty community health volunteers were trained to identify patients with laboratory-confirmed malaria in six peripheral health facilities located within six sub locations and subsequently followed them up to their homes to conduct a rapid assessment. Sampling and analysis of the results of the survey are based on Lot Quality Assurance. RESULTS: The tool was able to detect local heterogeneity in bed net coverage, bed net use and larval site abundance in the six health facility catchment areas. Nearly all the catchment areas met the action threshold for incomplete household coverage (i.e. not all household members not using a net the previous night) except the peri-urban area. Although the threshold for nets not in good condition was set very high (≥50%), only two catchment areas failed to meet the action threshold. On the indicator for "Net not used every day last week", half of the areas failed, while for net ownership, only two areas met the action threshold. CONCLUSION: The rapid assessment tool was able to detect marked heterogeneity in key indicators for malaria prevention between patients attending health facilities, and can distinguish between priority areas for intervention. There is need to validate it for use in other contexts.

Using pay for performance incentives (P4P) to improve management of suspected malaria fevers in rural Kenya: a cluster randomized controlled trial.

BACKGROUND: Inappropriate treatment of non-malaria fevers with artemisinin-based combination therapies (ACTs) is a growing concern, particularly in light of emerging artemisinin resistance, but it is a behavior that has proven difficult to change. Pay for performance (P4P) programs have generated interest as a mechanism to improve health service delivery and accountability in resource-constrained health systems. However, there has been little experimental evidence to establish the effectiveness of P4P in developing countries. We tested a P4P strategy that emphasized parasitological diagnosis and appropriate treatment of suspected malaria, in particular reduction of unnecessary consumption of ACTs. METHODS: A random sample of 18 health centers was selected and received a refresher workshop on malaria case management. Pre-intervention baseline data was collected from August to September 2012. Facilities were subsequently randomized to either the comparison (n = 9) or intervention arm (n = 9). Between October 2012 and November 2013, facilities in the intervention arm received quarterly incentive payments based on seven performance indicators. Incentives were for use by facilities rather than as payments to individual providers. All non-pregnant patients older than 1 year of age who presented to a participating facility and received either a malaria test or artemether-lumefantrine (AL) were eligible to be included in the analysis. Our primary outcome was prescription of AL to patients with a negative malaria diagnostic test (n = 11,953). Our secondary outcomes were prescription of AL to patients with laboratory-confirmed malaria (n = 2,993) and prescription of AL to patients without a malaria diagnostic test (analyzed at the cluster level, n = 178 facility-months). RESULTS: In the final quarter of the intervention period, the proportion of malaria-negative patients in the intervention arm who received AL was lower than in the comparison arm (7.3% versus 10.9%). The improvement from baseline to quarter 4 in the intervention arm was nearly three times that of the comparison arm (ratio of adjusted odds ratios for baseline to quarter 4 = 0.36, 95% CI: 0.24-0.57). The rate of prescription of AL to patients without a test was five times lower in the intervention arm (adjusted incidence rate ratio = 0.18, 95% CI: 0.07-0.48). Prescription of AL to patients with confirmed infection was not significantly different between the groups over the study period. CONCLUSIONS: Facility-based incentives coupled with training may be more effective than training alone and could complement other quality improvement approaches. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov (NCT01809873) on 11 March 2013.

Low correlation between household carbon monoxide and particulate matter concentrations from biomass-related pollution in three resource-poor settings.

Household air pollution from the burning of biomass fuels is recognized as the third greatest contributor to the global burden of disease. Incomplete combustion of biomass fuels releases a complex mixture of carbon monoxide (CO), particulate matter (PM) and other toxins into the household environment. Some investigators have used indoor CO concentrations as a reliable surrogate of indoor PM concentrations; however, the assumption that indoor CO concentration is a reasonable proxy of indoor PM concentration has been a subject of controversy. We sought to describe the relationship between indoor PM2.5 and CO concentrations in 128 households across three resource-poor settings in Peru, Nepal, and Kenya. We simultaneously collected minute-to-minute PM2.5 and CO concentrations within a meter of the open-fire stove for approximately 24h using the EasyLog-USB-CO data logger (Lascar Electronics, Erie, PA) and the personal DataRAM-1000AN (Thermo Fisher Scientific Inc., Waltham, MA), respectively. We also collected information regarding household construction characteristics, and cooking practices of the primary cook. Average 24h indoor PM2.5 and CO concentrations ranged between 615 and 1440 µg/m(3), and between 9.1 and 35.1 ppm, respectively. Minute-to-minute indoor PM2.5 concentrations were in a safe range (<25 µg/m(3)) between 17% and 65% of the time, and exceeded 1000 µg/m(3) between 8% and 21% of the time, whereas indoor CO concentrations were in a safe range (<7 ppm) between 46% and 79% of the time and exceeded 50 ppm between 4%, and 20% of the time. Overall correlations between indoor PM2.5 and CO concentrations were low to moderate (Spearman ρ between 0.59 and 0.83). There was also poor agreement and evidence of proportional bias between observed indoor PM2.5 concentrations vs. those estimated based on indoor CO concentrations, with greater discordance at lower concentrations. Our analysis does not support the notion that indoor CO concentration is a surrogate marker for indoor PM2.5 concentration across all settings. Both are important markers of household air pollution with different health and environmental implications and should therefore be independently measured.