Population health in Namibia: an analytical approach

Background and objectives: Namibia aims to improve population health and human development. As there is limited research to date exploring the sociodemographic patterns of disease and healthcare access in the country, this thesis aimed to assess the burden of infectious and non-communicable diseases, the coverage of public health interventions and barriers to healthcare access at the population level. Methods: Using data collected from 9,849 households and 41,646 individuals in the 2013 Namibia Demographic and Health Survey, the prevalence and sociodemographic patterns of disease and healthcare barriers were explored. Specifically, this thesis investigated the prevalence and distribution of chronic diseases, the coverage of public health interventions and access to healthcare. The determinants of these outcomes were assessed in descriptive, multivariable and spatial analyses. Results: In this DHS population, chronic disease prevalence was high (HIV: 13.9%; hypertension: 36.9% and hyperglycaemia: 5.4%). However, co-morbidity of these conditions was low. Malaria control intervention coverage was below government target levels in high transmission areas. In relation to healthcare access, almost half of women reported at least one barrier to healthcare, including distance to health facilities and getting money for treatment. Women who were less educated, less wealthy and lived in rural areas were more likely to report distance as a problem in accessing care. Spatial analyses indicated that distance and travel time to health facilities was highly variable in rural areas, with approximately 40% of the rural population having to travel for more than an hour to reach a facility. Multivariable analyses indicated that men, those who were less wealthy and lived in rural areas lived further away from health facilities. Health insurance was associated with health service utilisation but coverage of insurance was just 17.5%, with men, wealthier and more educated populations more likely to be insured. Conclusions: The findings presented in this thesis suggest that urban-rural and socioeconomic differences are underlying determinants of population health and healthcare access in Namibia, with rural, less wealthy and less educated populations often disadvantaged. Further research is needed to better understand disease co-morbidity, to evaluate intervention programmes, and to more intricately understand the population-level barriers to healthcare in the country so as to inform strategies to improve population health and achieve human development in Namibia.This research was funded by the Biomedical Research Counci

A cross-sectional analysis of ITN and IRS coverage in Namibia in 2013.

BACKGROUND: Achieving vector control targets is a key step towards malaria elimination. Because of variations in reporting of progress towards vector control targets in 2013, the coverage of these vector control interventions in Namibia was assessed. METHODS: Data on 9846 households, representing 41,314 people, collected in the 2013 nationally-representative Namibia Demographic and Health Survey were used to explore the coverage of two vector control methods: indoor residual spraying (IRS) and insecticide-treated nets (ITNs). Regional data on Plasmodium falciparum parasite rate in those aged 2-10 years (PfPR2-10), obtained from the Malaria Atlas Project, were used to provide information on malaria transmission intensity. Poisson regression analyses were carried out exploring the relationship between household interventions and PfPR2-10, with fully adjusted models adjusting for wealth and residence type and accounting for regional and enumeration area clustering. Additionally, the coverage as a function of government intervention zones was explored and models were compared using log-likelihood ratio tests. RESULTS: Intervention coverage was greatest in the highest transmission areas (PfPR2-10 ≥ 5%), but was still below target levels of 95% coverage in these regions, with 27.6% of households covered by IRS, 32.3% with an ITN and 49.0% with at least one intervention (ITN and/or IRS). In fully adjusted models, PfPR2-10 ≥ 5% was strongly associated with IRS (RR 14.54; 95% CI 5.56-38.02; p < 0.001), ITN ownership (RR 5.70; 95% CI 2.84-11.45; p < 0.001) and ITN and/or IRS coverage (RR 5.32; 95% CI 3.09-9.16; p < 0.001). CONCLUSIONS: The prevalence of IRS and ITN interventions in 2013 did not reflect the Namibian government intervention targets. As such, there is a need to include quantitative monitoring of such interventions to reliably inform intervention strategies for malaria elimination in Namibia

Association between early life antibiotic use and childhood overweight and obesity: a narrative review.

Background: Recent research implicates antibiotic use as a potential contributor to child obesity risk. In this narrative review, we examine current observational evidence on the relation between antibiotic use in early childhood and subsequent measures of child body mass. Methods: We searched PubMed, Web of Science and the Cochrane Library to identify studies that assessed antibiotic exposure before 3 years of age and subsequent measures of body mass or risk of overweight or obesity in childhood. Results: We identified 13 studies published before October 2017, based on a total of 6 81 332 individuals, which examined the relation between early life antibiotic exposure and measures of child body mass. Most studies did not appropriately account for confounding by indication for antibiotic use. Overall, we found no consistent and conclusive evidence of associations between early life antibiotic use and later child body mass [minimum overall adjusted odds ratio (aOR) reported: 1.01, 95% confidence interval (95% CI) 0.98-1.04, N = 2 60 556; maximum overall aOR reported: 2.56, 95% CI 1.36-4.79, N = 616], with no clinically meaningful increases in weight reported (maximum increase: 1.50 kg at 15 years of age). Notable methodological differences between studies, including variable measures of association and inclusion of confounders, limited more comprehensive interpretations. Conclusions: Evidence to date is insufficient to indicate that antibiotic use is an important risk factor for child obesity, or leads to clinically important differences in weight. Further comparable studies using routine clinical data may help clarify this association.This work was supported by the Wellcome Trust (grant number 206194), the African Partnership for Chronic Disease Research (Medical Research Council UK partnership grant number MR/K013491/1) and the National Institute for Health Research Cambridge Biomedical Research Centre (UK). EP is supported by the Gates Cambridge Trust

Variation analysis and gene annotation of eight MHC haplotypes: The MHC Haplotype Project

The human major histocompatibility complex (MHC) is contained within about 4 Mb on the short arm of chromosome 6 and is recognised as the most variable region in the human genome. The primary aim of the MHC Haplotype Project was to provide a comprehensively annotated reference sequence of a single, human leukocyte antigen-homozygous MHC haplotype and to use it as a basis against which variations could be assessed from seven other similarly homozygous cell lines, representative of the most common MHC haplotypes in the European population. Comparison of the haplotype sequences, including four haplotypes not previously analysed, resulted in the identification of >44,000 variations, both substitutions and indels (insertions and deletions), which have been submitted to the dbSNP database. The gene annotation uncovered haplotype-specific differences and confirmed the presence of more than 300 loci, including over 160 protein-coding genes. Combined analysis of the variation and annotation datasets revealed 122 gene loci with coding substitutions of which 97 were non-synonymous. The haplotype (A3-B7-DR15; PGF cell line) designated as the new MHC reference sequence, has been incorporated into the human genome assembly (NCBI35 and subsequent builds), and constitutes the largest single-haplotype sequence of the human genome to date. The extensive variation and annotation data derived from the analysis of seven further haplotypes have been made publicly available and provide a framework and resource for future association studies of all MHC-associated diseases and transplant medicine

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

A cross-sectional analysis of ITN and IRS coverage in Namibia in 2013.

BACKGROUND: Achieving vector control targets is a key step towards malaria elimination. Because of variations in reporting of progress towards vector control targets in 2013, the coverage of these vector control interventions in Namibia was assessed. METHODS: Data on 9846 households, representing 41,314 people, collected in the 2013 nationally-representative Namibia Demographic and Health Survey were used to explore the coverage of two vector control methods: indoor residual spraying (IRS) and insecticide-treated nets (ITNs). Regional data on Plasmodium falciparum parasite rate in those aged 2-10 years (PfPR2-10), obtained from the Malaria Atlas Project, were used to provide information on malaria transmission intensity. Poisson regression analyses were carried out exploring the relationship between household interventions and PfPR2-10, with fully adjusted models adjusting for wealth and residence type and accounting for regional and enumeration area clustering. Additionally, the coverage as a function of government intervention zones was explored and models were compared using log-likelihood ratio tests. RESULTS: Intervention coverage was greatest in the highest transmission areas (PfPR2-10 ≥ 5%), but was still below target levels of 95% coverage in these regions, with 27.6% of households covered by IRS, 32.3% with an ITN and 49.0% with at least one intervention (ITN and/or IRS). In fully adjusted models, PfPR2-10 ≥ 5% was strongly associated with IRS (RR 14.54; 95% CI 5.56-38.02; p < 0.001), ITN ownership (RR 5.70; 95% CI 2.84-11.45; p < 0.001) and ITN and/or IRS coverage (RR 5.32; 95% CI 3.09-9.16; p < 0.001). CONCLUSIONS: The prevalence of IRS and ITN interventions in 2013 did not reflect the Namibian government intervention targets. As such, there is a need to include quantitative monitoring of such interventions to reliably inform intervention strategies for malaria elimination in Namibia

Sociodemographic patterns of health insurance coverage in Namibia

Abstract Introduction Health insurance has been found to increase healthcare utilisation and reduce catastrophic health expenditures in a number of countries; however, coverage is often unequally distributed among populations. The sociodemographic patterns of health insurance in Namibia are not fully understood. We aimed to assess the prevalence of health insurance, the relation between health insurance and health service utilisation and to explore the sociodemographic factors associated with health insurance in Namibia. Such findings may help to inform health policy to improve financial access to healthcare in the country. Methods Using data on 14,443 individuals, aged 15 to 64 years, from the 2013 Namibia Demographic and Health Survey, the association between health insurance and health service utilisation was investigated using multivariable mixed effects Poisson regression analyses, adjusted for sociodemographic covariates and regional, enumeration area and household clustering. Multivariable mixed effects Poisson regression analyses were also conducted to explore the association between key sociodemographic factors and health insurance, adjusted for covariates and clustering. Effect modification by sex, education level and wealth quintile was also explored. Results Just 17.5% of this population were insured (men: 20.2%; women: 16.2%). In fully-adjusted analyses, education was significantly positively associated with health insurance, independent of other sociodemographic factors (higher education RR: 3.98; 95% CI: 3.11–5.10; p < 0.001). Female sex (RR: 0.83; 95% CI: 0.74–0.94; p = 0.003) and wealth (highest wealth quintile RR: 13.47; 95% CI: 9.06–20.04; p < 0.001) were also independently associated with insurance. There was a complex interaction between sex, education and wealth in the context of health insurance. With increasing education level, women were more likely to be insured (p for interaction < 0.001), and education had a greater impact on the likelihood of health insurance in lower wealth quintiles. Conclusions In this population, health insurance was associated with health service utilisation but insurance coverage was low, and was independently associated with sex, education and wealth. Education may play a key role in health insurance coverage, especially for women and the less wealthy. These findings may help to inform the targeting of strategies to improve financial protection from healthcare-associated costs in Namibia

A cross-sectional analysis of ITN and IRS coverage in Namibia in 2013

Abstract Background Achieving vector control targets is a key step towards malaria elimination. Because of variations in reporting of progress towards vector control targets in 2013, the coverage of these vector control interventions in Namibia was assessed. Methods Data on 9846 households, representing 41,314 people, collected in the 2013 nationally-representative Namibia Demographic and Health Survey were used to explore the coverage of two vector control methods: indoor residual spraying (IRS) and insecticide-treated nets (ITNs). Regional data on Plasmodium falciparum parasite rate in those aged 2–10 years (PfPR2–10), obtained from the Malaria Atlas Project, were used to provide information on malaria transmission intensity. Poisson regression analyses were carried out exploring the relationship between household interventions and PfPR2–10, with fully adjusted models adjusting for wealth and residence type and accounting for regional and enumeration area clustering. Additionally, the coverage as a function of government intervention zones was explored and models were compared using log-likelihood ratio tests. Results Intervention coverage was greatest in the highest transmission areas (PfPR2–10 ≥ 5%), but was still below target levels of 95% coverage in these regions, with 27.6% of households covered by IRS, 32.3% with an ITN and 49.0% with at least one intervention (ITN and/or IRS). In fully adjusted models, PfPR2–10 ≥ 5% was strongly associated with IRS (RR 14.54; 95% CI 5.56–38.02; p < 0.001), ITN ownership (RR 5.70; 95% CI 2.84–11.45; p < 0.001) and ITN and/or IRS coverage (RR 5.32; 95% CI 3.09–9.16; p < 0.001). Conclusions The prevalence of IRS and ITN interventions in 2013 did not reflect the Namibian government intervention targets. As such, there is a need to include quantitative monitoring of such interventions to reliably inform intervention strategies for malaria elimination in Namibia

Sociodemographic patterns of health insurance coverage in Namibia

Abstract Introduction Health insurance has been found to increase healthcare utilisation and reduce catastrophic health expenditures in a number of countries; however, coverage is often unequally distributed among populations. The sociodemographic patterns of health insurance in Namibia are not fully understood. We aimed to assess the prevalence of health insurance, the relation between health insurance and health service utilisation and to explore the sociodemographic factors associated with health insurance in Namibia. Such findings may help to inform health policy to improve financial access to healthcare in the country. Methods Using data on 14,443 individuals, aged 15 to 64 years, from the 2013 Namibia Demographic and Health Survey, the association between health insurance and health service utilisation was investigated using multivariable mixed effects Poisson regression analyses, adjusted for sociodemographic covariates and regional, enumeration area and household clustering. Multivariable mixed effects Poisson regression analyses were also conducted to explore the association between key sociodemographic factors and health insurance, adjusted for covariates and clustering. Effect modification by sex, education level and wealth quintile was also explored. Results Just 17.5% of this population were insured (men: 20.2%; women: 16.2%). In fully-adjusted analyses, education was significantly positively associated with health insurance, independent of other sociodemographic factors (higher education RR: 3.98; 95% CI: 3.11–5.10; p < 0.001). Female sex (RR: 0.83; 95% CI: 0.74–0.94; p = 0.003) and wealth (highest wealth quintile RR: 13.47; 95% CI: 9.06–20.04; p < 0.001) were also independently associated with insurance. There was a complex interaction between sex, education and wealth in the context of health insurance. With increasing education level, women were more likely to be insured (p for interaction < 0.001), and education had a greater impact on the likelihood of health insurance in lower wealth quintiles. Conclusions In this population, health insurance was associated with health service utilisation but insurance coverage was low, and was independently associated with sex, education and wealth. Education may play a key role in health insurance coverage, especially for women and the less wealthy. These findings may help to inform the targeting of strategies to improve financial protection from healthcare-associated costs in Namibia

Spatial and temporal structure of life cycle of Loligo forbesii and Loligo vulgaris in ecoregions of Celtic Seas and Greater North Sea

Cephalopod International Advisory Council Conference, Cephalopods in the Anthropocene: Multiple Challenges in a Changing Ocean, April 2-8, 2022, Sesimbra, PortugalThe Loligo vulgaris and L. forbesii co-occur in ecoregions of Celtic Seas and Greater North Sea and spatiotemporal structure of their ranges is poorly understood. To clarify interactions between two species we used a) biological data from German, Irish and UK research surveys (2016-2019); b) observation of Loligo egg masses by Scuba divers from Denmark, France, Germany, Netherlands, Norway and UK (2018-2021); c) sampling of commercial landings in France and UK (1991-2017). Spawning of L. vulgaris mostly takes place in the English Channel between December and March shifting in April-September along European shores up to Netherlands and Germany. Juveniles were recorded in the Channel area in June - October and the foraging range of larger squids (up to maturity) extends up to the southern Irish sea and North Sea. L. forbesii reproduces close to the shores of Ireland, Scotland and Norway in December – February, up to April. In in May-July spawning grounds extend into the Channel where mature females are recorded in landings and unidentified egg masses are abundant, whereas no mature L.vulgaris were found there. Juveniles forage in the entire North Sea in January – August and are found in November – December off Ireland and west of Scotland. Unidentified paralarvae of Loligo spp. are abundant from west English Channel to north of Scotland in December – March and in North Sea in January - August. Spawning grounds of both species are segregated due to different migratory patterns within the same range off Northwest European shoresN