HIV-prevalence mapping using Small Area Estimation in Kenya, Tanzania, and Mozambique at the first sub-national level

Local estimates of HIV-prevalence provide information that can be used to target interventions and consequently increase the efficiency of the resources. This closer-to-optimal allocation can lead to better health outcomes, including the control of the disease spread, and for more people. Producing reliable estimates at smaller geographical levels can be challenging and careful consideration of the nature of the data and the epidemiologic rational is needed. In this paper, we use the DHS data phase V to estimate HIV prevalence at the first-subnational level in Kenya, Tanzania, and Mozambique. We fit the data to a spatial random effect intrinsic conditional autoregressive (ICAR) model to smooth the outcome. We also use a sampling specification from a multistage cluster design. We found that Nyanza (P=14.2%) and Nairobi (P=7.8%) in Kenya, Iringa (P=16.2%) and Dar es Salaam (P=10.1%) in Tanzania, and Gaza (P=13.7%) and Maputo City (P=12.7%) in Mozambique are the regions with the highest prevalence of HIV, within country. Our results are based on statistically rigorous methods that allowed us to obtain an accurate visual representation of the HIV prevalence in the subset of African countries we chose. These results can help in identification and targeting of high-prevalent regions to increase the supply of healthcare services to reduce the spread of the disease and increase the health quality of people living with HIV.Comment: Pages: 10; Abstract: 221 words; Text: 2,076 words; Tables & Figures: 5; References: 1

Point-of-Care Testing for Anemia, Diabetes, and Hypertension: A Pharmacy-Based Model in Lima, Peru

Background: Prevention and control of chronic diseases is a high priority for many low- and middle-income countries. This study evaluated the feasibility and acceptability of training pharmacy workers to provide point-of-care testing for 3 chronic diseases—hypertension, diabetes, and anemia—to improve disease detection and awareness through private pharmacies. Methods: We developed a multiphase training curriculum for pharmacists and pharmacy technicians to build capacity for identification of risk factors, patient education, point-of-care testing, and referral for abnormal results. We conducted a pre-post evaluation with participants and evaluated results using Student 't' test for proportions. We conducted point-of-care testing with pharmacy clients and evaluated acceptability by patient characteristics (age, gender, and type of patient) using multiple logistic regression. Results: In total, 72 pharmacy workers (66%) completed the full training curriculum. Pretest scores indicated that pharmacists had more knowledge and skills in chronic disease risk factors, patient education, and testing than pharmacy technicians. All participants improved their knowledge and skills after the training, and post-test scores indicated that pharmacy technicians achieved the same level of competency as pharmacists ('P' < .01). Additionally, 698 clients received at least 1 test during the study; 53% completed the acceptability survey. Nearly 100% thought the pharmacy could provide faster results, faster and better attention, and better access to basic screening for hypertension, diabetes, and anemia than a traditional health center. Fast service was very important: 41% ranked faster results and 30% ranked faster attention as the most important factor for receiving diagnostic testing in the pharmacy. Discussion: We found that it is both feasible for pharmacies and acceptable to clients to train pharmacy workers to provide point-of-care testing for anemia, diabetes, and hypertension. This innovative approach holds potential to increase early detection of risk factors and bolster disease prevention and management efforts in Peru and other low- and middle-income settings

Cost of community-based human papillomavirus self-sampling in Peru : A micro-costing study

Declaration of Interest The authors declare no conflict of interest. Thomas Francis Jr. Fellowship provided funding for data collection. The Hope Project was funded by grants from Grand Challenges Canada (TTS-1812-21131), Uniting for Health Innovation, Global Initiative Against HPV and Cervical Cancer, University of Manitoba, and the John E. Fogarty International Center (5D43TW009375-05). None of the funders had any role in the study design, implementation, the process of data collection, data analysis, interpretation, or writing of the manuscript or the decision to submit it for publication. No authors have been paid to write this article by a pharmaceutical company or other agency. The authors were not precluded from accessing data in the study, and they accept responsibility to submit for publication. Publisher Copyright: © 2021 The Author(s)Background: Cost data of human papillomavirus (HPV) self-sampling programs from low-and-middle-income countries is limited. We estimated the total and unit costs associated with the Hope Project, a community-based HPV self-sampling social entrepreneurship in Peru. Methods: We conducted a micro-costing analysis from the program perspective to determine the unit costs of (1) recruitment/training of community women (Hope Ladies); (2) Hope Ladies distributing HPV self-sampling kits in their communities and the laboratory testing; and (3) Hope Ladies linking screened women with follow-up care. A procedural manual was used to identify the program's activities. A structured questionnaire and in-depth interviews were conducted with administrators to estimate the resource/time associated with activities. We obtained unit costs for each input previously identified from budgets and expenditure reports. Findings: From November 2018 to March 2020, the program recruited and trained 62 Hope Ladies who distributed 4,882 HPV self-sampling kits in their communities. Of the screened women, 586 (12%) tested HPV positive. The annual cost per Hope Lady recruited/trained was $147·51 (2018 USD). The cost per HPV self-sampling kit distributed/tested was$45·39, the cost per woman followed up with results was $55·64, and the cost per HPV-positive woman identified was$378·14. Personnel and laboratory costs represented 56·1% and 24·7% of the total programmatic cost, respectively. Interpretation: Our findings indicate that implementation of a community-based HPV self-sampling has competitive prices, which increases its likelihood to be feasible in Peru. Further economic evaluation is needed to quantify the incremental benefits of HPV self-sampling compared to more established options such as Pap tests. Funding: Thomas Francis Jr. Fellowship provided funding for data collection. The Hope Project was funded by grants from Grand Challenges Canada (TTS-1812-21131), Uniting for Health Innovation, Global Initiative Against HPV and Cervical Cancer, University of Manitoba, and the John E. Fogarty International Center (5D43TW009375-05).Peer reviewe

Carbon sequestration potential of second-growth forest regeneration in the Latin American tropics

Regrowth of tropical secondary forests following complete or nearly complete removal of forest vegetation actively stores carbon in aboveground biomass, partially counterbalancing carbon emissions from deforestation, forest degradation, burning of fossil fuels, and other anthropogenic sources. We estimate the age and spatial extent of lowland second-growth forests in the Latin American tropics and model their potential aboveground carbon accumulation over four decades. Our model shows that, in 2008, second-growth forests (1 to 60 years old) covered 2.4 million km2 of land (28.1%of the total study area).Over 40 years, these lands can potentially accumulate a total aboveground carbon stock of 8.48 Pg C (petagrams of carbon) in aboveground biomass via low-cost natural regeneration or assisted regeneration, corresponding to a total CO2 sequestration of 31.09 Pg CO2. This total is equivalent to carbon emissions from fossil fuel use and industrial processes in all of Latin America and the Caribbean from1993 to 2014. Ten countries account for 95% of this carbon storage potential, led by Brazil, Colombia, Mexico, and Venezuela. We model future land-use scenarios to guide national carbon mitigation policies. Permitting natural regeneration on 40% of lowland pastures potentially stores an additional 2.0 Pg C over 40 years. Our study provides information and maps to guide national-level forest-based carbon mitigation plans on the basis of estimated rates of natural regeneration and pasture abandonment. Coupled with avoided deforestation and sustainable forestmanagement, natural regeneration of second-growth forests provides a low-costmechanism that yields a high carbon sequestration potential with multiple benefits for biodiversity and ecosystem services. © 2016 The Authors

The Value of using local data to allocate resources to fight the HIV Epidemic. Case of study in Atlanta, Georgia

Thesis (Ph.D.)--University of Washington, 2022Local estimates can procure means to achieve a more equitable progress and end the HIV epidemic in the United States within the next decade. The aim of this dissertation was to quantify the incremental costs and health benefits of using prevalence data at the zip code level to inform resources allocation within Atlanta, Georgia, compared to the current distribution based on supply-side criteria.This study was structured in three aims. First, I conducted a simulation-based calibration of an HIV-mathematical model to project the epidemic at the zip code level under varying circumstances. Second, the CDC reports diagnosed HIV cases by zip code, but undiagnosed cases are unknown, which I predicted based on social determinants of HIV spreading and prevalence estimates at the county level. Third, I designed a cost-effective analysis (CEA) to quantify the health and economic consequences up to 2040 of allocating resources across zip codes under three alternatives: status quo, reallocation proportional to diagnosed-only- and to total-cases. For each scenario I estimated the incremental cost-effectiveness ratio (ICER), as the cost per quality-adjusted life year (QALY) gained, compared to the status quo. The CEA showed high variability across zip codes depending upon the direction of reallocation. Compared to the status, the reallocation alternative based on diagnoses-only were dominant among increased-coverage zip codes with costs savings of $13.8Million and 1,026 additional QALYs. Conversely, among decreased-coverage zip codes, the alternative was$3Million more expensive and yielded 2,019 less QALYs. The results under total-cases reallocation were the same across coverage-increased and -decreased zip codes and remarkably similar in the incremental effects. This study provides evidence that the health production function is heterogeneous across zip codes, making the reallocation of resources a non-zero-sum game. This implies the existence of a reallocation algorithm that maximizes the generation of QALYs while minimizing additional costs. These results create opportunities for prioritization of resources at the local level. While Atlanta provides an excellent setting to highlight the benefits of resources reallocation, several other cities have high variability of HIV spreading at the zip code level and presence residential segregation. Therefore, my analytical framework, methodology, and findings could be of interest in other cities and states across the country

Fluoride intake and fractional urinary fluoride excretion of Colombian preschool children

Aims: The purpose of this study was to assess the total fluoride intake and the fractional urinary fluoride excretion (FUFE) relative to the customary daily fluoride (F) ingestion in preschool children between 48-59 months of age. Design: Total fluoride ingestion, from dietary and toothpaste samples was determined in 120 young children, dwellers of four Colombian cities. A "duplicate plate" technique was used. In Colombia, table salt is fluoridated to a concentration of between 180-220 mg F/kg. Individual (n=96) FUFE values were calculated as the ratio between the total amount of F excreted in the urine and the total amount of F ingested, over a 24-hour period. Results: The average daily F-intake was 0.098 mg F/kg/day; 95% C.I. = 0.085-0.111 mg F/kg/day. The proportion of fluoride ingestion from toothpaste to the total fluoride intake was higher than 66% in all cities. The average FUFE values of subjects from each of the four Colombian cities under study did not differ significantly (ANOVA; p >0.91). The average 24-hour FUFE value for preschool children was 0.33; 95% C.I. = 0.29-0.37. Conclusions: The results obtained suggest that preschool children residing in Colombian urban areas are ingesting amounts of fluoride above the upper limit of the proposed safe threshold. FUFE values are similar to those reported in previous studies where daily F-doses were equal or higher than 0.064 mg F/kg

Modelación Estadística De Los Aportes De Las Vías Como Fuentes De Emisión A Las Partículas Totales En Suspensión Según Modelo MCF, Zona Centro De Medellín-Antioquía-Colombia, 2004

Sand fields, constructions, carbon boilers, roads, and biologic sources are air-contaminant-constituent factors in Down Town Valle de Aburrá, among others. The distribution of road contribution data to total suspended particles according to the source receptor model MCF, source correlation modeling, is nearly a Gamma distribution. Chi-square goodness of fit is used to model statistically. This test for goodness of fit also allows to estimate the parameters of the distribution utilizing maximum likelihood method. As a convergency criteria, the Estimation Maximization Algorithm is used. The mean of road contribution data to total suspended particles according to the source receptor model MCF, is straightforward and validates the road contribution factor to the atmospheric pollution of the zone under study: Entre las fuentes de emisión a la contaminación del aire en el Valle de Aburrá Zona Centro, se encuentran: canchas de arena, fuentes biológicas, calderas de carbón, vías y construcciones, entre otras. La forma funcional de los aportes de las Vías a las partículas totales en suspensión generados por el modelo fuente-receptor, MCF, Modelo de Correlación de Fuentes, creado para la estimación en porcentaje del grado de contribución de una fuente de contaminación especifica, es aproximadamente la de una distribución Gamma. Aquí se utiliza la prueba de bondad de ajuste Chi-cuadrado para modelar estadísticamente los aportes de las Vías como fuentes de emisión a las partículas totales en suspensión durante un periodo determinado de tiempo. Esta prueba permite estimar también los parámetros de la distribución mediante el método de máxima verosimilitud. Como algoritmo de convergencia se ha utilizado el Algoritmo EM (Estimation Maximization Algorithm). La estimación de la media de los factores de contribución de las Vías según el modelo Fuente-Receptor MCF es inmediata a partir de estas estimaciones y valida el factor de contribución de las Vías a la contaminación atmosférica en la zona de estudi

Estimating the costs of adolescent HIV care visits and an intervention to facilitate transition to adult care in Kenya.

IntroductionAdolescents with HIV in sub-Saharan Africa face challenges transitioning to adult HIV care, which can affect long-term HIV care adherence and retention. An adolescent transition package (ATP) focused on transition tools can improve post-transition clinical outcomes, but its implementation costs are unknown.MethodsWe estimated the average cost per patient of an HIV care visit and ATP provision to adolescents. Data was collected from 13 HIV clinics involved in a randomized clinical trial evaluating ATP in western Kenya. We conducted a micro-costing and activity-driven time estimation to assess costs from the provider perspective. We developed a flow-map, conducted staff interviews, and completed time and motion observation. ATP costs were estimated as the difference in average cost for an HIV care transition visit in the intervention compared to control facilities. We assessed uncertainty in costing estimates via Monte Carlo simulations.ResultsThe average cost of an adolescent HIV care visit was 29.8USD (95%CI 27.5, 33.4) in the standard of care arm and 32.9USD (95%CI 30.5, 36.8) in the ATP intervention arm, yielding an incremental cost of 3.1USD (95%CI 3.0, 3.4) for the ATP intervention. The majority of the intervention cost (2.8USD) was due ATP booklet discussion with the adolescent.ConclusionThe ATP can be feasibly implemented in HIV care clinics at a modest increase in overall clinic visit cost. Our cost estimates can be used to inform economic evaluations or budgetary planning of adolescent HIV care interventions in Kenya

The Impact of Rubella Vaccine Introduction on Rubella Infection and Congenital Rubella Syndrome: A Systematic Review of Mathematical Modelling Studies

Introduction: Rubella vaccines have been used to prevent rubella and congenital rubella syndrome (CRS) in several World Health Organization (WHO) regions. Mathematical modelling studies have simulated introduction of rubella-containing vaccines (RCVs), and their results have been used to inform rubella introduction strategies in several countries. This systematic review aimed to synthesize the evidence from mathematical models regarding the impact of introducing RCVs. Methods: We registered the review in the international prospective register of systematic reviews (PROSPERO) with registration number CRD42020192638. Systematic review methods for classical epidemiological studies and reporting guidelines were followed as far as possible. A comprehensive search strategy was used to identify published and unpublished studies with no language restrictions. We included deterministic and stochastic models that simulated RCV introduction into the public sector vaccination schedule, with a time horizon of at least five years. Models focused only on estimating epidemiological parameters were excluded. Outcomes of interest were time to rubella and CRS elimination, trends in incidence of rubella and CRS, number of vaccinated individuals per CRS case averted, and cost-effectiveness of vaccine introduction strategies. The methodological quality of included studies was assessed using a modified risk of bias tool, and a qualitative narrative was provided, given that data synthesis was not feasible. Results: Seven studies were included from a total of 1393 records retrieved. The methodological quality was scored high for six studies and very high for one study. Quantitative data synthesis was not possible, because only one study reported point estimates and uncertainty intervals for the outcomes. All seven included studies presented trends in rubella incidence, six studies reported trends in CRS incidence, two studies reported the number vaccinated individuals per CRS case averted, and two studies reported an economic evaluation measure. Time to CRS elimination and time to rubella elimination were not reported by any of the included studies. Reported trends in CRS incidence showed elimination within five years of RCV introduction with scenarios involving mass vaccination of older children in addition to routine infant vaccination. CRS incidence was higher with RCV introduction than without RCV when public vaccine coverage was lower than 50% or only private sector vaccination was implemented. Although vaccination of children at a given age achieved slower declines in CRS incidence compared to mass campaigns targeting a wide age range, this approach resulted in the lowest number of vaccinated individuals per CRS case averted. Conclusion and recommendations: We were unable to conduct data synthesis of included studies due to discrepancies in outcome reporting. However, qualitative assessment of results of individual studies suggests that vaccination of infants should be combined with vaccination of older children to achieve rapid elimination of CRS. Better outcomes are obtained when rubella vaccination is introduced into public vaccination schedules at coverage figures of 80%, as recommended by WHO, or higher. Guidelines for reporting of outcomes in mathematical modelling studies and the conduct of systematic reviews of mathematical modelling studies are required