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Yacob Pinchevsky,1 Neil Butkow,1 Frederick J Raal,2 Tobias Chirwa,3 Alan Rothberg4 1Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 2Carbohydrate and Lipid Metabolism Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 3Division of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 4School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South AfricaCorrespondence: Yacob Pinchevsky 7 York Road, Parktown, Johannesburg 2193, South AfricaTel +27 82 837 4082Fax +27 11 026 4700Email jpinchevsky@gmail.comAbstract: Diabetes mellitus is a complex and chronic condition that requires lifelong management and interaction with a healthcare system. Failure to control risk factors through preventive care may lead to a host of diabetes-related complications. Underperforming healthcare systems and poor awareness among the general population/healthcare professionals has been suggested as reasons why so many patients remain undiagnosed. Due to the asymptomatic nature of early and even intermediate diabetes mellitus, several years may pass without any diagnosis before complications begin to manifest. Other factors include age, gender, ethnicity, education, marital and unemployment status which may also increase the risk of developing morbidity and mortality associated with diabetes mellitus. This review summarizes the current demographic risk factors and clinical characteristics associated with diabetes mellitus. A literature search was conducted using PubMed, MEDLINE, and Sabinet by using the following search terms: diabetes mellitus, risk factors, characteristics and complications.Keywords: diabetes mellitus, risk factors, characteristics, complications

Yacob Pinchevsky,1 Frederick Raal,2 Neil Butkow,1 Tobias Chirwa,3 Larry Distiller,4 Alan Rothberg5 1Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 2Carbohydrate and Lipid Metabolism Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 3Division of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 4Centre for Diabetes and Endocrinology, Johannesburg, South Africa; 5School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Purpose: With the realities of resource constraints existing in South Africa’s public sector and the evidence of disparities in health care between populations, the study sought to compare the quality of diabetes care and health-related quality of life (HRQoL) in patients with type 2 diabetes mellitus (T2DM) receiving care within two specialized settings: one in the public and the other in the private sector. Particular emphasis was placed on complication rates at the two sites.Patients and methods: Quantitative and qualitative data were collected between June and October 2016 from existing patients’ records at each setting. Data included patient demographics, potential barriers to accessing care, medical history, laboratory results, pharmacological treatment and diabetes-related clinical, biochemical and HRQoL outcomes. With outcome measurements being the priority, methodology incorporated the Donabedian model in which “structure” of health care systems, access to care and processes of care are key to determine outcomes.Results: A total of 290 T2DM patients were enrolled. Analysis revealed that private patients were predominantly Caucasian with higher socioeconomic indicators (p

Peter Nyasulu,1,2 Simon Sikwese,2,3 Tobias Chirwa,2 Chandra Makanjee,4 Madalitso Mmanga,5 Joseph Omoniyi Babalola,6 James Mpunga,7 Hastings T Banda,8 Adamson S Muula,9,10 Alister C Munthali11 1Division of Epidemiology and Biostatistics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, 2School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 3Pakachere Institute of Health and Development Communication, Blantyre, Malawi; 4Department of Medical Radiation Sciences, University of Canberra, Canberra, WA, Australia; 5District TB Office, Department of Environmental Health, District Health Office, Ntcheu, Malawi; 6Division of Community Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 7National Tuberculosis Control Program, Community Health Sciences Unit, Ministry of Health, Lilongwe, 8Research for Equity and Community Health (REACH) Trust, Lilongwe, 9Department of Community Health, College of Medicine, University of Malawi, Blantyre, 10African Centre of Excellence in Public Health and Herbal Medicine, College of Medicine, University of Malawi, Blantyre, 11Centre for Social Research, University of Malawi, Zomba, Malawi Introduction: The global burden of tuberculosis (TB) remains significantly high, with overreliance on biomedical interventions and inadequate exploration of the socioeconomic and cultural context of the infected population. A desired reduction in disease burden can be enhanced through a broader theoretical understanding of people’s health beliefs and concerns about TB. In this qualitative study, we explore the knowledge, beliefs, and perceptions of community members and people diagnosed with TB toward TB in Ntcheu district, Malawi. Methods: Using a qualitative phenomenological study design, data were obtained from eight focus-group discussions and 16 individual in-depth interviews. The community’s experiences and perceptions of TB were captured without using any preconceived framework. Adult participants who had had or never had a diagnosis of TB were purposively selected by sex and age and enrolled for the study. Discussions and individual interviews lasting about 60 minutes each were audiotaped, transcribed, and translated into English and analyzed using MaxQDA 10 software for qualitative analysis. Results: Most participants believed that TB was curable and would go for diagnosis if they had symptoms suggestive of the disease. However, based on their beliefs, individuals expressed some apprehension about the spread of TB and the social implications of being diagnosed with the disease. This perception affected participants’ responses about seeking diagnosis and treatment. Conclusion: A supportive and collective approach consisting of a combination of mass media, interactive communication campaigns, emphasizing TB symptoms, transmission, and stigma could be useful in addressing barriers to early diagnosis and care-seeking behavior. Keywords: tuberculosis, knowledge, perception of TB, beliefs, Ntcheu, Malawi

Yacob Pinchevsky,1 Varada J Shukla,1 Neil Butkow,1 Tobias Chirwa,2 Frederick Raal3 1Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, 2Division of Epidemiology and Biostatistics, School of Public Health, 3Carbohydrate and Lipid Metabolism Research Unit, Division of Endocrinology and Metabolism, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Purpose: Our study set out to examine if disparities in control of glycated hemoglobin (HbA1c), blood pressure (BP), and low-density-lipoprotein cholesterol (LDL-C) existed among an urban multi-ethnic cohort of South Africans, living with type 2 diabetes mellitus (T2DM).Patients and methods: This longitudinal, retrospective study consisted of 261 men and women with previously diagnosed T2DM who attended Charlotte Maxeke Johannesburg Academic Hospital, South Africa across two time periods 2009 and 2013. Demographic and clinical data were extracted from consecutive medical records. The primary outcome was to determine achievements in HbA1c, BP, and LDL-C among ethnic groups using evidence-based goals.Results: The mean age of the cohort was 64 (±10.6) years, females represented 55%, and the self-reported diabetes duration was 16 (±10.6) years as at 2013. Black Africans (42.9%, n=112 of 261) were more likely to reach the HbA1c target (

Peter Nyasulu,1,3 Susan Kambale,2 Tobias Chirwa,3 Teye Umanah,3 Isaac Singini,4 Simon Sikwese,5 Hastings T Banda,6 Rhoda P Banda,7 Henry Chimbali,8 Bagrey Ngwira,9 Alister Munthali10 1Department of Public Health, School of Health Sciences, Monash University, Johannesburg, South Africa; 2World Health Organization, Country Office, Lilongwe, Malawi; 3School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 4Johns Hopkins Research Project, College of Medicine, University of Malawi, 5Pakachere Institute of Health and Development Communication, Blantyre, 6Research for Equity and Community Health (REACH) Trust, Lilongwe, 7National Tuberculosis Control Program, Community Health Sciences Unit, Ministry of Health, Lilongwe, 8Health Promotion Section, Ministry of Health, Lilongwe, 9Department of Community Health, College of Medicine, University of Malawi, Blantyre, 10Centre for Social Research, University of Malawi, Zomba, Malawi Background: Knowledge and perceptions about tuberculosis (TB) can influence care-seeking behavior and adherence to treatment. Previous studies in Malawi were conducted to assess knowledge and attitudes regarding TB in adults, with limited data on knowledge in children. Objectives: This study assessed knowledge and perceptions about TB in children aged 10–14 years attending primary school in Ntcheu District, Malawi. Design: A cross-sectional study was conducted in four primary schools in Ntcheu District. Data on knowledge and perception of TB were collected using a structured questionnaire. Pearson chi-square test was used to determine the association between socioeconomic factors and TB knowledge and perception. A P0.05). Conclusion: Lack of knowledge regarding TB and gaps identified, may be due to a deficiency in the content of the school curriculum or the availability of information, education, and communication materials. This is the first study to report on knowledge and perceptions of TB among primary school learners in Malawi. These results will inform the development of relevant information, education, and communication materials to enhance awareness about TB among school going children. Keywords: tuberculosis, knowledge, perceptions, health seeking, adherence, Malawi

Rasmussen encephalitis (RE) is a rare neuroinflammatory disease characterized by intractable seizures and progressive atrophy on one side of the cerebrum. Perivascular cuffing and clusters of T cells in the affected cortical hemisphere are indicative of an active cellular immune response. Methods: Peripheral blood mononuclear cells (PBMCs) and brain-infiltrating lymphocytes (BILs) were isolated from 20 RE surgery specimens by standard methods, and CD3+ T cell populations were analyzed by flow cytometry. Gamma delta T cell receptor spectratyping was carried out by nested PCR of reversed transcribed RNA extracted from RE brain tissue, followed by high resolution capillary electrophoresis. A MiSeq DNA sequencing platform was used to sequence the third complementarity determining region (CDR3) of δ1 chains. Results: CD3+ BILs from all of the RE brain specimens comprised both aαβ and γδ T cells. The median aαβ:γδ ratio was 1.9 (range 0.58-5.2) compared with a median ratio of 7.7 (range 2.7-40.8) in peripheral blood from the same patients. The aαβ T cells isolated from brain tissue were predominantly CD8+, and the majority of γδ T cells were CD4- CD8-. Staining for the early activation marker CD69 showed that a fraction of the aαβ and γδ T cells in the BILs were activated (median 42 %; range 13-91 %, and median 47 %; range 14-99 %, respectively). Spectratyping T cell receptor (TCR) Vδ1-3 chains from 14 of the RE brain tissue specimens indicated that the γδ T cell repertoire was relatively restricted. Sequencing δ1 chain PCR fragments revealed that the same prevalent CDR3 sequences were found in all of the brain specimens. These CDR3 sequences were also detected in brain tissue from 15 focal cortical dysplasia (FCD) cases. Conclusion: Neuroinflammation in RE involves both activated aαβ and γδ T cells. The presence of γδ T cells with identical TCR δ1 chain CDR3 sequences in all of the brain specimens examined suggests that a non-major histocompatibility complex (MHC)-restricted immune response to the same antigen(s) is involved in the etiology of RE. The presence of the same δ1 clones in CD brain implies the involvement of a common inflammatory pathway in both diseases.

Objective To develop a model for identifying areas at high risk for sporadic measles outbreaks based on an analysis of factors associated with a national outbreak in South Africa between 2009 and 2011. Methods Data on cases occurring before and during the national outbreak were obtained from the South African measles surveillance programme, and data on measles immunization and population size, from the District Health Information System. A Bayesian hierarchical Poisson model was used to investigate the association between the risk of measles in infants in a district and first- dose vaccination coverage, population density, background prevalence of human immunodeficiency virus (HIM) infection and expected failure of seroconversion. Model projections were used to identify emerging high-risk areas in 2012. Findings A clear spatial pattern of high-risk areas was noted, with many interconnected (i.e. neighbouring) areas. An increased risk of measles outbreak was significantly associated with both the preceding build-up of a susceptible population and population density. The risk was also elevated when more than 20% of infants in a populous area had missed a first vaccine dose. The model was able to identify areas at high risk of experiencing a measles outbreak in 2012 and where additional preventive measures could be undertaken. Conclusion The South African measles outbreak was associated with the build-up of a susceptible population (owing to poor vaccine coverage), high prevalence of HIV infection and high population density. The predictive model developed could be applied to other settings susceptible to sporadic outbreaks of measles and other vaccine-preventable diseases. Objectif Mettre au point un modele permettant d'identifier les zones a haut risque d'epidemies sporadiques de rougeole, sur la base d'une analyse des facteurs associes a une epidemie nationale en Afrique du Sud, entre 2009 et 2011. Methodes Les donnees sur les cas survenus avant et pendant I'epidemie nationale ont ete obtenues aupres du programme sud-africain de surveillance de la rougeole, et les donnees sur la vaccination contre la rougeole et la taille de la population aupres du systeme d'informations sanitaires des districts. Un modele hierarchique bayesien de Poisson a ete utilise pour etudier l'association entre le risque de rougeole chez les nourrissons dans un district et la couverture vaccinale pour la premiere dose, la densite de population, la prevalence sous-jacente de l'infection par le virus de l'immunodeficience humaine (VIH) et l'echec attendu de la seroconversion. Les projections du modele ont ete utilisees pour identifier les nouvelles zones a haut risque en 2012. Resultat Un schema spatial clair des zones a haut risque a ete observe, avec de nombreuses zones interconnectees (c'est-a-dire voisines). Un risque accru d'epidemie de rougeole a ete significativement associe a la constitution prealable d'une population vulnerable ainsi qu'a la densite de population. Le risque etait aussi eleve lorsque plus de 20% des nourrissons dans une zone fortement peuplee n'avaient pas recu une premiere dose du vaccin. Le modele a ete en mesure d'identifier les zones a haut risque d'epidemie de rougeole en 2012, ainsi que la ou des mesures preventives supplementaires pourraient etre prises. Conclusion L'epidemie de rougeole en Afrique du Sud a ete associee a la constitution d'une population vulnerable (en raison d'une couverture vaccinale mediocre), a la prevalence elevee de l'infection par le VIH et a une forte densite de population. Le modele predictif developpe pourrait etre applique a d'autres contextes sensibles aux epidemies sporadiques de rougeole et a d'autres maladies qui peuvent etre prevenues par la vaccination. Objetivo Desarrollar un modelo para identificar las areas con riesgo alto de sufrir brotes esporadicos de sarampion en base a un analisis de los factores asociados a un brote nacional en Sudafrica entre los anos 2009 y 2011. Metodos Los datos de los casos ocurridos antes y durante el brote nacional se obtuvieron del programa de vigilancia del sarampion de Sudafrica, y la informacion acerca de la vacunacion contra el sarampion y el tamano de la poblacion, del sistema de informacion sanitaria por distritos. Se empleo un modelo de Poisson jerarquico bayesiano para investigar la relacion entre el riesgo de sarampion en ninos de un distrito con la cobertura de la primera dosis de la vacuna, la densidad de poblacion, el historial de prevalencia de la infeccion por el virus de la inmunodeficiencia humana (VlH) y el fracaso previsto de la seroconversion. Las proyecciones del modelo se utilizaron para identificar areas de alto riesgo nuevas en 2012. Resultados Se observo un patron espacial claro de las areas de alto riesgo con muchas zonas conectadas (esto es, colindantes). El riesgo superior de sufrir un brote de sarampion se asocio de modo significativo tanto con el crecimiento previo de un grupo de poblacion vulnerable como con la densidad de poblacion, y tambien fue elevado cuando mas del 20% de los ninos en un area populosa no habia recibido la primera dosis de la vacuna. El modelo fue capaz de identificar las areas con riesgo alto de sufrir un brote de sarampion en 2012 y donde podrian emprenderse medidas de prevencion adicionales. Conclusion El brote de sarampion en Sudafrica estuvo asociado con el aumento de un grupo de poblacion vulnerable (debido a una cobertura de vacunacion insuficiente), una prevalencia elevada de la infeccion por VIH y una densidad de poblacion alta. El modelo predictivo desarrollado podria aplicarse a otros lugares susceptibles de sufrir brotes esporadicos de sarampion y otras enfermedades inmunoprevenibles., Introduction Measles is highly contagious and the transmission intensity (1) of the measles virus exceeds that of most human pathogens. (2) Despite progress in controlling measles since 2000, the disease [...]

Objective: To develop a sepsis care bundle for the initial management of maternal sepsis in low resource settings.Design: Modified Delphi process.Setting: Participants from 34 countries.Population: Healthcare practitioners working in low resource settings (n = 143; 34 countries), members of an expert panel (n = 11) and consultation with the World Health Organization Global Maternal and Neonatal Sepsis Initiative technical working group.Methods: We reviewed the literature to identify all potential interventions and practices around the initial management of sepsis that could be bundled together. A modified Delphi process, using an online questionnaire and in-person meetings, was then undertaken to gain consensus on bundle items. Participants ranked potential bundle items in terms of perceived importance and feasibility, considering their use in both hospitals and health centres. Findings from the healthcare practitioners were then triangulated with those of the experts.Main Outcome Measure: Consensus on bundle items.Results: Consensus was reached after three consultation rounds, with the same items deemed most important and feasible by both the healthcare practitioners and expert panel. Final bundle items selected were: (1) Fluids, (2) Antibiotics, (3) Source identification and control, (4) Transfer (to appropriate higher-level care) and (5) Monitoring (of both mother and neonate as appropriate). The bundle was given the acronym 'FAST-M'.Conclusion: A clinically relevant maternal sepsis bundle for low resource settings has been developed by international consensus.Tweetable Abstract: A maternal sepsis bundle for low resource settings has been developed by international consensus. [ABSTRACT FROM AUTHOR]

This paper aims to empirically investigate the relevance of exogenous growth models to explaining economic growth in three Southern African countries, using the ARDL bounds-testing approach. In addition, the relevance of the convergence hypothesis in these study countries is tested using an extended exogenous growth model. The study results reveal that the predictions of the Solow and augmented Solow growth models are consistent in the three study countries, and that the convergence hypothesis holds. However, when additional factors are taken into account in exogenous growth models, the response of income per capita due to changes in investment and human capital development is slow in economies with low income per capita, such as Malawi and Zambia, compared to South Africa, which is ranked as an economy with a high income per capita. This study has important policy implications in these study countries. These implications include the need for policymakers to ensure that macroeconomic stability is encouraged by reducing government consumption, inflation, and population growth; and by promoting trade in order to allow for the diffusion of technologies from abroad.

Purpose: The purpose of this study was to assess radiographer familiarity and preferences with digital radiography in four teaching hospitals and thereafter make recommendations in line with the migration from screen film to digital radiography. Materials and Methods: A questionnaire was designed to collect data from either qualified or student radiographers from four teaching hospitals. From the four teaching hospitals, there were a total of 205 potential respondents. Among other things, responses regarding experiences and preferences with digital radiography, quality control procedures, patient dose, advantages and disadvantages of digital radiography were sought. The information collected was based on self-reporting by the participants. The study is exploratory in nature and descriptive statistics were generated from the collected data using Microsoft Excel 2007 and StatsDirect software. Results: Sixty-three out of 205 (31%) radiographers from all the four radiology centers responded to the circulated questionnaire. Only 15% (8) of the qualified radiographers had 4 or more years of experience with digital radiography compared to 68% (36) for the same amount of experience with screen-film radiography. Sixty-one percent (38) of the participants had been exposed to digital radiography during their lectures while at university. A small proportion, 16% (10) of the respondents underwent formal training in quality control procedures on the digital X-ray units they were using. Slightly more than half (55%) of the participants felt it was easier for them to retake an image in digital radiography than in screen film radiography. Conclusion: The results of this survey showed that the participants are familiar with digital radiography and have embraced this relatively new technology as shown by the fact that they can identify both its advantages and disadvantages as applied to clinical practice. However, there are minimal quality control procedures specific to digital radiography being undertaken as such there is need for formal education, continuing education and manufacturer training with respect to quality control as institutions make the transition from conventional screen film radiology to digital radiology. [ABSTRACT FROM AUTHOR]

Our objective was to determine the effectiveness of an intervention that incorporated education about the 'six cleans' with the use of a clean delivery kit in preventing cord infection and puerperal sepsis. A stepped-wedge, cross-sectional study was conducted in 10 surveillance sites across two rural districts of Mwanza Region, Tanzania. A total of 3262 pregnant women between the ages of 17 and 45 years were enrolled in the study. Village health workers administered questionnaires to each mother at 5 days postpartum and inspected the infants' umbilical cord stumps for signs of infection. Newborns whose mothers used the delivery kit were 13.1 times less likely to develop cord infection than infants whose mothers did not use the kit. Furthermore, women who used the kit for delivery were 3.2 times less likely to develop puerperal sepsis than women who did not use the kit. Women who bathed before delivery were 2.6 times less likely to develop puerperal sepsis than women who did not bathe, and their infants were 3.9 times less likely to develop cord infection. Single-use delivery kits, when combined with education about clean delivery, can have a positive impact on the health of women and their newborns by significantly decreasing the likelihood of developing puerperal sepsis or cord infection. [ABSTRACT FROM AUTHOR]

Abstract Background Advances in neonatal care allow survival of extremely premature infants, who are at risk of handicap. Neurodevelopmental follow up of these infants is an essential part of ongoing evaluation of neonatal care. The neonatal care in resource limited developing countries is very different to that in first world settings. Follow up data from developing countries is essential; it is not appropriate to extrapolate data from units in developed countries. This study provides follow up data on a population of very low birth weight (VLBW) infants in Johannesburg, South Africa. Methods The study sample included all VLBW infants born between 01/06/2006 and 28/02/2007 and discharged from the neonatal unit at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). Bayley Scales of Infant and Toddler Development Version 111 (BSID) 111 were done to assess development. Regression analysis was done to determine factors associated with poor outcome. Results 178 infants were discharged, 26 were not available for follow up, 9 of the remaining 152 (5.9%) died before an assessment was done; 106 of the remaining 143 (74.1%) had a BSID 111 assessment. These 106 patients form the study sample; mean birth weight and mean gestational age was 1182 grams (SD: 197.78) and 30.81 weeks (SD: 2.67) respectively. The BSID (111) was done at a median age of 16.48 months. The mean cognitive subscale was 88.6 (95% CI: 85.69 - 91.59), 9 (8.5%) were < 70, mean language subscale was 87.71 (95% CI: 84.85 - 90.56), 10 (9.4%) < 70, and mean motor subscale was 90.05 (95% CI: 87.0 - 93.11), 8 (7.6%) < 70. Approximately one third of infants were identified as being at risk (score between 70 and 85) on each subscale. Cerebral palsy was diagnosed in 4 (3.7%) of babies. Factors associated with poor outcome included cystic periventricular leukomalacia (PVL), resuscitation at birth, maternal parity, prolonged hospitalisation and duration of supplemental oxygen. PVL was associated with poor outcome on all three subscales. Birth weight and gestational age were not predictive of neurodevelopmental outcome. Conclusion Although the neurodevelopmental outcome of this group of VLBW infants was within the normal range, with a low incidence of cerebral palsy, these results may reflect the low survival of babies with a birth weight below 900 grams. In addition, mean subscale scores were low and one third of the babies were identified as "at risk", indicating that this group of babies warrants long-term follow up into school going age.

Abstract Background Many sub-Saharan countries are confronted with persistently high levels of infant mortality because of the impact of a range of biological and social determinants. In particular, infant mortality has increased in sub-Saharan Africa in recent decades due to the HIV/AIDS epidemic. The geographic distribution of health problems and their relationship to potential risk factors can be invaluable for cost effective intervention planning. The objective of this paper is to determine and map the spatial nature of infant mortality in South Africa at a sub district level in order to inform policy intervention. In particular, the paper identifies and maps high risk clusters of infant mortality, as well as examines the impact of a range of determinants on infant mortality. A Bayesian approach is used to quantify the spatial risk of infant mortality, as well as significant associations (given spatial correlation between neighbouring areas) between infant mortality and a range of determinants. The most attributable determinants in each sub-district are calculated based on a combination of prevalence and model risk factor coefficient estimates. This integrated small area approach can be adapted and applied in other high burden settings to assist intervention planning and targeting. Results Infant mortality remains high in South Africa with seemingly little reduction since previous estimates in the early 2000's. Results showed marked geographical differences in infant mortality risk between provinces as well as within provinces as well as significantly higher risk in specific sub-districts and provinces. A number of determinants were found to have a significant adverse influence on infant mortality at the sub-district level. Following multivariable adjustment increasing maternal mortality, antenatal HIV prevalence, previous sibling mortality and male infant gender remained significantly associated with increased infant mortality risk. Of these antenatal HIV sero-prevalence, previous sibling mortality and maternal mortality were found to be the most attributable respectively. Conclusions This study demonstrates the usefulness of advanced spatial analysis to both quantify excess infant mortality risk at the lowest administrative unit, as well as the use of Bayesian modelling to quantify determinant significance given spatial correlation. The "novel" integration of determinant prevalence at the sub-district and coefficient estimates to estimate attributable fractions further elucidates the "high impact" factors in particular areas and has considerable potential to be applied in other locations. The usefulness of the paper, therefore, not only suggests where to intervene geographically, but also what specific interventions policy makers should prioritize in order to reduce the infant mortality burden in specific administration areas.

Abstract Background The successful suppression of a target insect population using the sterile insect technique (SIT) partly depends on the premise that the laboratory insects used for mass rearing are genetically compatible with the target population, that the mating competitiveness of laboratory reared males is at least comparable to that of their wild counterparts, and that mass rearing and sterilization processes do not in themselves compromise male fitness to a degree that precludes them from successfully competing for mates in the wild. This study investigated the fitness and sexual cross-compatibility between samples of field collected and laboratory reared An. arabiensis under laboratory conditions. Results The physiological and reproductive fitness of the MALPAN laboratory strain is not substantially modified with respect to the field population at Malahlapanga. Further, a high degree of mating compatibility between MALPAN and the Malahlapanga population was established based on cross-mating experiments. Lastly, the morphological characteristics of hybrid ovarian polytene chromosomes further support the contention that the MALPAN laboratory colony and the An. arabiensis population at Malahlapanga are genetically homogenous and therefore compatible. Conclusions It is concluded that the presence of a perennial and isolated population of An. arabiensis at Malahlapanga presents a unique opportunity for assessing the feasibility of SIT as a malaria vector control option. The MALPAN laboratory colony has retained sufficient enough measures of reproductive and physiological fitness to present as a suitable candidate for male sterilization, mass rearing and subsequent mass release of sterile males at Malahlapanga in order to further assess the feasibility of SIT in a field setting.