Evaluation of knowledge, attitude, practices and effectiveness of menstrual hygiene interventions in rural schools from Lilongwe, Malawi.

BACKGROUND: Menstrual hygiene management (MHM) is associated with the menstrual process in women and adolescent girls who face cultural and financial challenges in rural areas of many developing countries. As part of the pilot study, we assessed the sustainability and effectiveness of the approaches and lessons learned from the MHM project intervention in rural areas of Lilongwe, Malawi. METHODS: Rural primary schools (n = 4) were purposively selected where an MHM intervention was implemented in Lilongwe, Malawi. The study employed a mixed-method research design. Assessments and data collection were performed through surveys of learners, literature reviews, key informant interviews (KIIs) (n = 90), and 20 focus group discussions (FGDs). The study participants included boys and adolescent girls (n = 100, 11-19 years; grades 5-8), teachers, mother groups, and community leaders from the selected schools. RESULTS: All the schools had water sanitation and hygiene facilities and latrines (45% improved, 54% ventilated improved pit latrines - VIPs) that promoted menstrual hygiene for adolescent girls. However, two of the schools studied (50%, n = 4) did not have separate washrooms for changing sanitary materials. There was a slight increase in latrine coverage in Kabuthu zone communities (90% at baseline versus 93.4% at midterm). However, the coverage dropped to 85.7% at the final evaluation, which was attributed to too much rain received in the area that damaged most of the latrines. There was a significant reduction (p < 0.05) in the number of girls failing to attend classes due to menstruation (70% at baseline versus 14% at final evaluation). Furthermore, the project resulted in the majority of girls (94.4%) having access to school. There was a strong uptake and adoption of sanitary products (reusable pads and menstrual cups) among adolescent girls of all age groups. The study has demonstrated that the inclusion of key stakeholders such as health workers, parents, mother groups and community leaders promoted the uptake and sustainability of reusable pads and menstrual cups and MHM interventions and programs. CONCLUSION: The MHM project implementation improved adolescent girls' education in the area. The inclusion of boys and other key stakeholders in the health education talks addressed issues of stigma and discrimination. The study, therefore, calls for comprehensive training on MHM and hygiene education to remove discrimination and harmful cultural practices.

Prevalence of Endemic Respiratory Viruses During the COVID-19 Pandemic in Urban and Rural Malawi.

Background: We investigated endemic respiratory virus circulation patterns in Malawi, where no lockdown was imposed, during the COVID-19 pandemic. Methods: Within a prospective household cohort in urban and rural Malawi, adult participants provided upper respiratory tract (URT) samples at 4 time points between February 2021 and April 2022. Polymerase chain reaction (PCR) was performed for SARS-CoV-2, influenza, and other endemic respiratory viruses. Results: 1626 URT samples from 945 participants in 542 households were included. Overall, 7.6% (n = 123) samples were PCR- positive for >1 respiratory virus; SARS-CoV-2 (4.4%) and rhinovirus (2.0%) were most common. No influenza A virus was detected. Influenza B and respiratory syncytial virus (RSV) were rare. Higher virus positivity were detected in the rural setting and at earlier time points. Coinfections were infrequent. Conclusions: Endemic respiratory viruses circulated in the community in Malawi during the pandemic, though influenza and RSV were rarely detected. Distinct differences in virus positivity and demographics were observed between urban and rural cohorts.

Waist circumference and glycaemia are strong predictors of progression to diabetes in individuals with prediabetes in sub-Saharan Africa: 4-year prospective cohort study in Malawi.

Sub-Saharan Africa is projected to have the highest increase in the number of people with diabetes worldwide. However, the drivers of diabetes in this region have not been clearly elucidated. The aim of this study was to evaluate the incidence of diabetes and the predictors of progression in a population-based cohort with impaired fasting glucose (IFG) in Malawi. We used data from an extensive rural and urban non-communicable disease survey. One hundred seventy-five, of 389 individuals with impaired fasting glucose (IFG) at baseline, age 48 ±15 years and body mass index 27.5 ±5.9 kg/m2 were followed up for a median of 4.2 years (714 person-years). Incidence rates were calculated, and predictors of progression to diabetes were analysed using multivariable logistic regression models, with overall performance determined using receiver operator characteristics (ROC) curves. The median follow-up was 4.2 (IQR 3.4-4.7) years. Forty-five out of 175 (26%) progressed to diabetes. Incidence rates of diabetes were 62.9 per 1000 person-years 95% CI, 47.0-84.3. The predictors of progression were higher; age (odds ratio [OR] 1.48, P = 0.046), BMI (OR 1.98, P = 0.001), waist circumference (OR 2.50,P<0.001), waist-hip ratio (OR 1.40, P = 0.03), systolic blood pressure (OR 1.56, P = 0.01), fasting plasma glucose (OR 1.53, P = 0.01), cholesterol (OR 1.44, P = 0.05) and low-density lipoprotein cholesterol (OR 1.80, P = 0.002). A simple model combining fasting plasma glucose and waist circumference was predictive of progression to diabetes (ROC area under the curve = 0.79). The incidence of diabetes in people with IFG is high in Malawi and predictors of progression are like those seen in other populations. Our data also suggests that a simple chart with probabilities of progression to diabetes based on waist circumference and fasting plasma glucose could be used to identify those at risk of progression in clinical settings in sub-Saharan Africa.

Assessing the impact of the COVID-19 restrictions on HIV testing services in Malawi: an interrupted time series analysis.

Background: Restrictions on public gatherings and movement to mitigate the spread of COVID-19 may have disrupted access and availability of HIV services in Malawi. We quantified the impact of these restrictions on HIV testing services in Malawi.Methods: We conducted an interrupted time series analysis of routine aggregated programme data from 808 public and private, adult and paediatric health facilities across rural and urban communities in Malawi between January 2018 and March 2020 (pre-restrictions) and April to December 2020 (post restrictions), with April 2020 as the month restrictions took effect. Positivity rates were expressed as the proportion of new diagnoses per 100 persons tested. Data were summarised using counts and median monthly tests stratified by sex, age, type of health facility and service delivery points at health facilities. The immediate effect of restriction and post-lockdown outcomes trends were quantified using negative binomial segmented regression models adjusted for seasonality and autocorrelation.Results: The median monthly number of HIV tests and diagnosed people living with HIV (PLHIV) declined from 261 979 (interquartile range [IQR] 235 654-283 293) and 7 929 (IQR 6 590-9 316) before the restrictions, to 167 307 (IQR 161 122-185 094) and 4 658 (IQR 4 535-5 393) respectively, post restriction. Immediately after restriction, HIV tests declined by 31.9% (incidence rate ratio [IRR] 0.681; 95% CI 0.619-0.750), the number of PLHIV diagnosed declined by 22.8% (IRR 0.772; 95% CI 0.695-0.857), while positivity increased by 13.4% (IRR 1.134; 95% CI 1.031-1.247). As restrictions eased, total HIV testing outputs and the number of new diagnoses increased by an average of 2.3% each month (slope change: 1.023; 95% CI 1.010-1.037) and 2.5% (slope change:1.025; 95% CI 1.012-1.038) respectively. Positivity remained similar (slope change: 1.001; 95% CI 0.987-1.015). Unlike general trends noted, while HIV testing services among children aged <12 months declined 38.8% (IRR 0.351; 95% CI 0.351-1.006) with restrictions, recovery has been minimal (slope change: 1.008; 95% CI 0.946-1.073).Conclusion: COVID-19 restrictions were associated with significant but short-term declines in HIV testing services in Malawi, with differential recovery in these services among population subgroups, especially infants. While efforts to restore HIV testing services are commendable, more nuanced strategies that promote equitable recovery of HIV testing services can ensure no subpopulations are left behind.

The Cost of Providing Comprehensive HIV Services to Key Populations: An Analysis of the LINKAGES Program in Kenya and Malawi.

INTRODUCTION: Timely data on HIV service costs are critical for estimating resource needs and allocating funding, but few data exist on the cost of HIV services for key populations (KPs) at higher risk of HIV infection in low- and middle-income countries. We aimed to estimate the total and per contact annual cost of providing comprehensive HIV services to KPs to inform planning and budgeting decisions. METHODS: We collected cost data from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV (LINKAGES) program in Kenya and Malawi serving female and male sex workers, men who have sex with men, and transgender women. Data were collected prospectively for fiscal year (FY) 2019 and retrospectively for start-up activities conducted in FY2015 and FY2016. Data to estimate economic costs from the provider's perspective were collected from LINKAGES headquarters, country offices, implementing partners (IPs), and drop-in centers (DICs). We used top-down and bottom-up cost estimation approaches. RESULTS: Total economic costs for FY2019 were US$6,175,960 in Kenya and US$4,261,207 in Malawi. The proportion of costs incurred in IPs and DICs was 66% in Kenya and 42% in Malawi. The costliest program areas were clinical services, management, peer outreach, and monitoring and data use. Mean cost per contact was US$127 in Kenya and US$279 in Malawi, with a mean cost per contact in DICs and IPs of US$63 in Kenya and US$104 in Malawi. CONCLUSION: Actions undertaken above the service level in headquarters and country offices along with those conducted below the service level in communities, comprised important proportions of KP HIV service costs. The costs of pre-service population mapping and size estimation activities were not negligible. Costing studies that focus on the service level alone are likely to underestimate the costs of delivering HIV services to KPs.

Estimating the cost of HIV services for key populations provided by the LINKAGES program in Kenya and Malawi.

BACKGROUND: Data remain scarce on the costs of HIV services for key populations (KPs). The objective of this study was to bridge this gap in the literature by estimating the unit costs of HIV services delivered to KPs in the LINKAGES program in Kenya and Malawi. We estimated the mean total unit costs of seven clinical services: post-exposure prophylaxis (PEP), pre-exposure prophylaxis (PrEP), HIV testing services (HTS), antiretroviral therapy (ART), sexually transmitted infection (STI) services, sexual and reproductive health (SRH) services, and management of sexual violence (MSV). These costs take into account the costs of non-clinical services delivered alongside clinical services and the pre-service and above-service program management integral to the LINKAGES program. METHODS: Data were collected at all implementation levels of the LINKAGES program including 30 drop-in-centers (DICs) in Kenya and 15 in Malawi. This study was conducted from the provider's perspective. We estimated economic costs for FY 2019 and cost estimates include start-up costs. Start-up and capital costs were annualized using a discount rate of 3%. We used a combination of top-down and bottom-up costing approaches. Top-down methods were used to estimate the costs of headquarters, country offices, and implementing partners. Bottom-up micro-costing methods were used to measure the quantities and prices of inputs used to produce services in DICs. Volume-weighted mean unit costs were calculated for each clinical service. Costs are presented in 2019 United States dollars (US$). RESULTS: The mean total unit costs per service ranged from US$18 (95% CI: 16, 21) for STI services to US$635 (95% CI: 484, 785) for PrEP in Kenya and from US$41 (95% CI: 37, 44) for STI services to US$1,240 (95% CI 1156, 1324) for MSV in Malawi. Clinical costs accounted for between 21 and 59% of total mean unit costs in Kenya, and between 25 and 38% in Malawi. Indirect costs-including start-up activities, the costs of KP interventions implemented alongside clinical services, and program management and data monitoring-made up the remaining costs incurred. CONCLUSIONS: A better understanding of the cost of HIV services is highly relevant for budgeting and planning purposes and for optimizing HIV services. When considering all service delivery costs of a comprehensive HIV service package for KPs, costs of services can be significantly higher than when considering direct clinical service costs alone. These estimates can inform investment cases, strategic plans and other budgeting exercises.

Characterizing the evolving SARS-CoV-2 seroprevalence in urban and rural Malawi between February 2021 and April 2022: A population-based cohort study.

OBJECTIVES: This study aimed to investigate the changing SARS-CoV-2 seroprevalence and associated health and sociodemographic factors in Malawi between February 2021 and April 2022. METHODS: In total, four 3-monthly serosurveys were conducted within a longitudinal population-based cohort in rural Karonga District and urban Lilongwe, testing for SARS-CoV-2 S1 immunoglobulin (Ig)G antibodies using an enzyme-linked immunosorbent assay. Population seroprevalence was estimated in all and unvaccinated participants. Bayesian mixed-effects logistic models estimated the odds of seropositivity in the first survey, and of seroconversion between surveys, adjusting for age, sex, occupation, location, and assay sensitivity/specificity. RESULTS: Of the 2005 participants (Karonga, n = 1005; Lilongwe, n = 1000), 55.8% were female and median age was 22.7 years. Between Surveys (SVY) 1 and 4, population-weighted SARS-CoV-2 seroprevalence increased from 26.3% to 89.2% and 46.4% to 93.9% in Karonga and Lilongwe, respectively. At SVY4, seroprevalence did not differ by COVID-19 vaccination status in adults, except for those aged 30+ years in Karonga (unvaccinated: 87.4%, 95% credible interval 79.3-93.0%; two doses: 98.1%, 94.8-99.5%). Location and age were associated with seroconversion risk. Individuals with hybrid immunity had higher SARS-CoV-2 seropositivity and antibody titers, than those infected. CONCLUSION: High SARS-CoV-2 seroprevalence combined with low morbidity and mortality indicate that universal vaccination is unnecessary at this stage of the pandemic, supporting change in national policy to target at-risk groups.

HIV Testing Approaches to Optimize Prevention and Treatment for Key and Priority Populations in Malawi.

Background: Despite progress in improving antiretroviral therapy (ART) for people with HIV in Malawi, the burden of HIV infections and HIV treatment outcomes among key populations is suboptimal. Client-centered differentiated service delivery approaches may facilitate addressing HIV prevention and treatment needs of key populations in Malawi. Methods: De-identified program data routinely collected as part of the LINKAGES project-Malawi were assembled from October 2017 to September 2019. HIV case finding was compared across different testing modalities for each population. Poisson regression was used to estimate the association between testing modalities and ART initiation. Results: Of the 18 397 people included in analyses, 10 627 (58%) were female sex workers (FSWs), 2219 (12%) were men who have sex with men (MSM), and 4970 (27%) were clients of FSWs. HIV case finding varied by modality and population, with index testing and enhanced peer outreach demonstrating high yield despite reaching relatively few individuals. FSWs who tested positive through risk network referral testing were more likely to initiate ART within 30 days compared with those who tested positive through clinic-based testing (adjusted risk ratio [aRR], 1.50; 95% CI, 1.23-1.82). For MSM, index testing (aRR, 1.45; 95% CI, 1.06-2.00) and testing through a drop-in center (aRR, 1.82; 95% CI, 1.19-2.78) were associated with 30-day ART initiation. Conclusions: These data suggest that differentiated HIV testing and outreach approaches tailored to the needs of different key populations may facilitate improved ART initiation in Malawi. Achieving 0 new infections by 2030 suggests the need to adapt treatment strategies given individual and structural barriers to treatment for key populations with HIV in high-prevalence settings.

BCG re-vaccination in Malawi: 30-year follow-up of a large, randomised, double-blind, placebo-controlled trial.

BACKGROUND: A large, double-blind, randomised, placebo-controlled trial of repeat BCG found 49% efficacy against leprosy but no protection against tuberculosis after 6-9 years' follow-up in 1995. We report here additional follow-up, which resulted in greatly increased tuberculosis case numbers, and allowed subgroup analysis. METHODS: Nearly 47 000 individuals of all ages living in northern Malawi with a BCG vaccine scar were randomly assigned (1:1) between 1986 and 1989 to receive a second BCG or placebo. The investigators and project staff remained masked to all interventions. Enhanced passive surveillance ensured ascertainment of tuberculosis and leprosy to the end of 2018. Tuberculosis case definitions included rigorous microbiological or histological confirmation. Prespecified subgroup analyses were by tuberculosis type, age at vaccination, time since vaccination, previous tuberculin reactivity, HIV status and Mycobacterium tuberculosis lineage. The original trial is registered with ISRCTN registry, ISRCTN11311670. FINDINGS: In follow-up until Dec 31, 2018, 824 participants had developed tuberculosis, including 786 with pulmonary disease, of whom 383 (63%) of 607 with known HIV status were HIV positive. There was no effect of a second BCG overall (odds ratio [OR] 0·92; 95% CI 0·80-1·05), or for pulmonary (0·93; 0·81-1·07), or lymph node tuberculosis (0·60; 0·31-1·17). The OR was lower for those with known HIV-negative tuberculosis (0·77; 0·59-1·00), for those vaccinated as children (aged <5 years, 0·74; 0·41-1·35; aged 5-14 years, 0·77; 0·60-0·99), and for cases arising at least 20 years after vaccination (0·79; 0·63-1·01). There were no differences by tuberculin status at vaccination, or lineage. There was no evidence of protection against leprosy beyond 10 years after vaccination (although there have been only nine diagnostically certain cases since 1995). INTERPRETATION: There was no evidence that repeat BCG vaccination provides appreciable protection against overall tuberculosis in this rural African population with a high prevalence of HIV. Subgroup effects should not be overinterpreted given the multiple analyses done. However, the evidence for modest protection against HIV-negative tuberculosis, and for a delayed benefit in those vaccinated as children, is consistent with other observations in the literature. FUNDING: LEPRA, Wellcome Trust, Bill & Melinda Gates Foundation.

Readiness for Use of HIV Preexposure Prophylaxis Among Men Who Have Sex With Men in Malawi: Qualitative Focus Group and Interview Study.

BACKGROUND: Men who have sex with men (MSM) are a key group for HIV interventions in Malawi considering their high HIV prevalence (17.5% compared to 8.4% among men in the general population). The use of oral preexposure prophylaxis (PrEP) presents a new opportunity for MSM to be protected. We present the findings from a qualitative assessment designed to assess awareness of and willingness and barriers to using PrEP among MSM in Malawi. OBJECTIVE: The 3 main objectives of this assessment were to determine: (1) awareness of PrEP, (2) factors that influence willingness to use PrEP, and (3) potential barriers to PrEP use and adherence among MSM in order to guide the design and implementation of a PrEP program in Malawi. METHODS: Ahead of the introduction of PrEP in Malawi, a qualitative study using in-depth interviews (IDIs) and focus group discussions (FGDs) was conducted in October 2018 in Blantyre, Lilongwe, and rural districts of Mzimba North and Mangochi. With support of members of the population, study participants were purposively recruited from 4 MSM-friendly drop-in centers where MSM receive a range of health services to ensure representativeness across sites and age. Participants were asked what they had heard about PrEP, their willingness to use PrEP, their barriers to PrEP use, and their preferences for service delivery. The data were analyzed using a thematic content analysis framework that was predetermined in line with objectives. RESULTS: A total of 109 MSM were interviewed-13 through IDIs and 96 through FGDs. Most participants were aware of PrEP as a new HIV intervention but had limited knowledge related to its use. However, the majority were willing to use it and were looking forward to having access to it. IDI participants indicated that they will be more willing to take PrEP if the dosing frequency were appropriate and MSM were involved in information giving and distribution of the drug. FGD participants emphasized that places of distribution and characteristics of the service provider are the key factors that will affect use. Knowing the benefits of PrEP emerged as a key theme in both the IDIs and FGDs. Participants highlighted barriers that would hinder them from taking PrEP such as side effects which were cited in IDIs and FGDs. Key factors from FGDs include cost, fear of being outed, drug stockouts, fear of being known as MSMs by wives, and lack of relevant information. FGDs cited stigma from health care workers, forgetfulness, and community associated factors. CONCLUSIONS: Despite having inadequate knowledge about PrEP, study participants were largely willing to use PrEP if available. Programs should include an effective information, education, and communication component around their preferences and provide PrEP in MSM-friendly sites.

Associations between low HDL, sex and cardiovascular risk markers are substantially different in sub-Saharan Africa and the UK: analysis of four population studies.

INTRODUCTION: Low high-density lipoprotein (HDL) is widely used as a marker of cardiovascular disease risk, although this relationship is not causal and is likely mediated through associations with other risk factors. Low HDL is extremely common in sub-Saharan African populations, and this has often been interpreted to indicate that these populations will have increased cardiovascular risk. We aimed to determine whether the association between HDL and other cardiovascular risk factors differed between populations in sub-Saharan Africa and the UK. METHODS: We compared data from adults living in Uganda and Malawi (n=26 216) and in the UK (n=8747). We examined unadjusted and adjusted levels of HDL and applied the WHO recommended cut-offs for prevalence estimates. We used spline and linear regression to assess the relationship between HDL and other cardiovascular risk factors. RESULTS: HDL was substantially lower in the African than in the European studies (geometric mean 0.9-1.2 mmol/L vs 1.3-1.8 mmol/L), with African prevalence of low HDL as high as 77%. Total cholesterol was also substantially lower (geometric mean 3.3-3.9 mmol/L vs 4.6-5.4 mmol/L). In comparison with European studies the relationship between HDL and adiposity (body mass index, waist to hip ratio) was greatly attenuated in African studies and the relationship with non-HDL cholesterol reversed: in African studies low HDL was associated with lower non-HDL cholesterol. The association between sex and HDL was also different; using the WHO sex-specific definitions, low HDL was substantially more common among women (69%-77%) than men (41%-59%) in Uganda/Malawi. CONCLUSION: The relationship between HDL and sex, adiposity and non-HDL cholesterol in sub-Saharan Africa is different from European populations. In sub-Saharan Africans low HDL is a marker of low overall cholesterol and sex differences are markedly attenuated. Therefore low HDL in isolation is unlikely to indicate raised cardiovascular risk and the WHO sex-based cut-offs are inappropriate.

Evaluation of Host Serum Protein Biomarkers of Tuberculosis in sub-Saharan Africa.

Accurate and affordable point-of-care diagnostics for tuberculosis (TB) are needed. Host serum protein signatures have been derived for use in primary care settings, however validation of these in secondary care settings is lacking. We evaluated serum protein biomarkers discovered in primary care cohorts from Africa reapplied to patients from secondary care. In this nested case-control study, concentrations of 22 proteins were quantified in sera from 292 patients from Malawi and South Africa who presented predominantly to secondary care. Recruitment was based upon intention of local clinicians to test for TB. The case definition for TB was culture positivity for Mycobacterium tuberculosis; and for other diseases (OD) a confirmed alternative diagnosis. Equal numbers of TB and OD patients were selected. Within each group, there were equal numbers with and without HIV and from each site. Patients were split into training and test sets for biosignature discovery. A nine-protein signature to distinguish TB from OD was discovered comprising fibrinogen, alpha-2-macroglobulin, CRP, MMP-9, transthyretin, complement factor H, IFN-gamma, IP-10, and TNF-alpha. This signature had an area under the receiver operating characteristic curve in the training set of 90% (95% CI 86-95%), and, after adjusting the cut-off for increased sensitivity, a sensitivity and specificity in the test set of 92% (95% CI 80-98%) and 71% (95% CI 56-84%), respectively. The best single biomarker was complement factor H [area under the receiver operating characteristic curve 70% (95% CI 64-76%)]. Biosignatures consisting of host serum proteins may function as point-of-care screening tests for TB in African hospitals. Complement factor H is identified as a new biomarker for such signatures.

A comparison of the associations between adiposity and lipids in Malawi and the United Kingdom.

BACKGROUND: The prevalence of excess adiposity, as measured by elevated body mass index (BMI) and waist-hip ratio (WHR), is increasing in sub-Saharan African (SSA) populations. This could add a considerable burden of cardiovascular and metabolic diseases for which these populations are currently ill-prepared. Evidence from white, European origin populations shows that higher adiposity leads to an adverse lipid profile; whether these associations are similar in all SSA populations requires further exploration. This study compared the association of BMI and WHR with lipid profile in urban Malawi with a contemporary cohort with contrasting socioeconomic, demographic, and ethnic characteristics in the United Kingdom (UK). METHODS: We used data from 1248 adolescents (mean 18.7 years) and 2277 Malawian adults (mean 49.8 years), all urban-dwelling, and from 3201 adolescents (mean 17.8 years) and 6323 adults (mean 49.7 years) resident in the UK. Adiposity measures and fasting lipids were assessed in both settings, and the associations of BMI and WHR with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) were assessed by sex and age groups in both studies. RESULTS: Malawian female adults were more adipose and had more adverse lipid profiles than their UK counterparts. In contrast, Malawian adolescent and adult males were leaner and had more favourable lipid profiles than in the UK. Higher BMI and WHR were associated with increased TC, LDL-C and TG and reduced HDL-C in both settings. The magnitude of the associations of BMI and WHR with lipids was mostly similar or slightly weaker in the Malawian compared with the UK cohort in both adolescents and adults. One exception was the stronger association between increasing adiposity and elevated TC and LDL-C in Malawian compared to UK men. CONCLUSIONS: Malawian adult women have greater adiposity and more adverse lipid profiles compared with their UK counterparts. Similar associations of adiposity with adverse lipid profiles were observed for Malawian and UK adults in most age and sex groups studied. Sustained efforts are urgently needed to address the excess adiposity and adverse lipid profiles in Malawi to mitigate a future epidemic of cardio-metabolic disease among the poorest populations.

Bayesian reconstruction of Mycobacterium tuberculosis transmission networks in a high incidence area over two decades in Malawi reveals associated risk factors and genomic variants.

Understanding host and pathogen factors that influence tuberculosis (TB) transmission can inform strategies to eliminate the spread of Mycobacterium tuberculosis (Mtb). Determining transmission links between cases of TB is complicated by a long and variable latency period and undiagnosed cases, although methods are improving through the application of probabilistic modelling and whole-genome sequence analysis. Using a large dataset of 1857 whole-genome sequences and comprehensive metadata from Karonga District, Malawi, over 19 years, we reconstructed Mtb transmission networks using a two-step Bayesian approach that identified likely infector and recipient cases, whilst robustly allowing for incomplete case sampling. We investigated demographic and pathogen genomic variation associated with transmission and clustering in our networks. We found that whilst there was a significant decrease in the proportion of infectors over time, we found higher transmissibility and large transmission clusters for lineage 2 (Beijing) strains. By performing evolutionary convergence testing (phyC) and genome-wide association analysis (GWAS) on transmitting versus non-transmitting cases, we identified six loci, PPE54, accD2, PE_PGRS62, rplI, Rv3751 and Rv2077c, that were associated with transmission. This study provides a framework for reconstructing large-scale Mtb transmission networks. We have highlighted potential host and pathogen characteristics that were linked to increased transmission in a high-burden setting and identified genomic variants that, with validation, could inform further studies into transmissibility and TB eradication.

Prevalence of impaired renal function among rural and urban populations: findings of a cross-sectional study in Malawi.

Background: Sub-Saharan Africa faces region-specific risk factors for chronic kidney disease (CKD), such as nephrotoxic herbal medicines, antiretroviral therapy and infections, in addition to hypertension and diabetes. However, large epidemiological studies from this area are scarce. Methods: In a cross-sectional survey of non-communicable diseases, we conducted a prevalence sub-study of CKD in two Malawian populations. Study participants (N=5264) of 18 years of age and above were recruited and data on demographics and CKD risk factors were collected. Glomerular filtration rate was estimated (eGFR) using the CKD-EPI equation. Results: The prevalence of eGFR<60ml/min/1.73m 2 was 1.4% (95% CI 1.1 - 1.7%) and eGFR<90ml/min/1.73m 2 was 20.6% (95% CI 19.5 - 21.7%). The rural area had higher age-standardized prevalence of both eGFR<60ml/min/1.73m 2, at 1.8% (95% CI 1.4 - 2.3) and eGFR <90 ml/min/1.73m², at 21.1% (95% CI 19.9 - 22.3), than urban location, which had a prevalence of 1.5%, (95% CI 1.0 - 2.2) and 19.4% (95% CI 18.0 - 20.8), respectively, with overlapping confidence intervals. The prevalence of CKD was lower in females than in males in both rural and urban areas. Older age (p < 0.001), a higher level of education (p = 0.03) and hypertension (p < 0.001) were associated with a higher adjusted odds ratio (aOR) of low eGFR. Diabetes was associated with a reduced aOR of eGFR<90ml/min/1.73m 2 of 0.69 (95% CI 0.49-0.96; p=0.03). Of participants with eGFR<60ml/min/1.73m 2, 14 (19.4%) had no history of hypertension, diabetes or HIV, while 36 (50%) had a single risk factor of being hypertensive. Conclusion s: Impaired renal function is prevalent, but lower than expected, in rural and urban Malawi. Further research is needed to increase understanding of CKD incidence, survival and validation of eGFR calculations in this population.

Sex and area differences in the association between adiposity and lipid profile in Malawi.

BACKGROUND: Evidence from high-income countries shows that higher adiposity results in an adverse lipid profile, but it is unclear whether this association is similar in Sub-Saharan African (SSA) populations. This study aimed to assess the association between total and central adiposity measures and lipid profile in Malawi, exploring differences by sex and area of residence (rural/urban). METHODS: In this cross-sectional study, data from 12 096 rural and 12 847 urban Malawian residents were used. The associations of body mass index (BMI) and waist to hip ratio (WHR) with fasting lipids (total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TG)) were assessed by area and sex. RESULTS: After adjusting for potential confounders, higher BMI and WHR were linearly associated with increased TC, LDL-C and TG and reduced HDL-C. BMI was more strongly related to fasting lipids than was WHR. The associations of adiposity with adverse lipid profile were stronger in rural compared with urban residents. For instance, one SD increase in BMI was associated with 0.23 mmol/L (95% CI 0.19 to 0.26) increase in TC in rural women and 0.13 mmol/L (95% CI 0.11 to 0.15) in urban women. Sex differences in the associations between adiposity and lipids were less evident. CONCLUSIONS: The consistent associations observed of higher adiposity with adverse lipid profiles in men and women living in rural and urban areas of Malawi highlight the emerging adverse cardio-metabolic epidemic in this poor population. Our findings underline the potential utility of BMI in estimating cardiovascular risk and highlight the need for greater investment to understand the long-term health outcomes of obesity and adverse lipid profiles and the extent to which lifestyle changes and treatments effectively prevent and modify adverse cardio-metabolic outcomes.

Identifying mixed Mycobacterium tuberculosis infections from whole genome sequence data.

BACKGROUND: Mixed, polyclonal Mycobacterium tuberculosis infection occurs in natural populations. Developing an effective method for detecting such cases is important in measuring the success of treatment and reconstruction of transmission between patients. Using whole genome sequence (WGS) data, we assess two methods for detecting mixed infection: (i) a combination of the number of heterozygous sites and the proportion of heterozygous sites to total SNPs, and (ii) Bayesian model-based clustering of allele frequencies from sequencing reads at heterozygous sites. RESULTS: In silico and in vitro artificially mixed and known pure M. tuberculosis samples were analysed to determine the specificity and sensitivity of each method. We found that both approaches were effective in distinguishing between pure strains and mixed infection where there was relatively high (> 10%) proportion of a minor strain in the mixture. A large dataset of clinical isolates (n = 1963) from the Karonga Prevention Study in Northern Malawi was tested to examine correlations with patient characteristics and outcomes with mixed infection. The frequency of mixed infection in the population was found to be around 10%, with an association with year of diagnosis, but no association with age, sex, HIV status or previous tuberculosis. CONCLUSIONS: Mixed Mycobacterium tuberculosis infection was identified in silico using whole genome sequence data. The methods presented here can be applied to population-wide analyses of tuberculosis to estimate the frequency of mixed infection, and to identify individual cases of mixed infections. These cases are important when considering the evolution and transmission of the disease, and in patient treatment.

Dietary sodium intake in urban and rural Malawi, and directions for future interventions.

Background: High dietary sodium intake is a major risk factor for hypertension. Data on population sodium intake are scanty in sub-Saharan Africa, despite a high hypertension prevalence in most countries. Objective: We aimed to determine daily sodium intake in urban and rural communities in Malawi. Design: In an observational cross-sectional survey, data were collected on estimated household-level per capita sodium intake, based on how long participants reported that a defined quantity of plain salt lasts in a household. In a subset of 2078 participants, 24-h urinary sodium was estimated from a morning spot urine sample. Results: Of 29,074 participants, 52.8% of rural and 50.1% of urban individuals lived in households with an estimated per capita plain salt consumption >5 g/d. Of participants with urinary sodium data, 90.8% of rural and 95.9% of urban participants had estimated 24-h urinary sodium >2 g/d; there was no correlation between household per capita salt intake and estimated 24-h urinary sodium excretion. Younger adults were more likely to have high urinary sodium and to eat food prepared outside the home than were those over the age of 60 y. Households with a member with previously diagnosed hypertension had reduced odds (OR: 0.59; 95% CI: 0.51, 0.68) of per capita household plain salt intake >5 g/d, compared with those where hypertension was undiagnosed. Conclusions: Sodium consumption exceeds the recommended amounts for most of the population in rural and urban Malawi. Population-level interventions for sodium intake reduction with a wide focus are needed, targeting both sources outside the home as well as home cooking. This trial was registered at clinicaltrials.gov as NCT03422185.

Glycated haemoglobin A1c (HbA1c) for detection of diabetes mellitus and impaired fasting glucose in Malawi: a diagnostic accuracy study.

OBJECTIVES: To examine the accuracy of glycated haemoglobin A1c (HbA1c) in detecting type 2 diabetes and impaired fasting glucose among adults living in Malawi. DESIGN: A diagnostic validation study of HbA1c. Fasting plasma glucose (FPG) ≥7.0 mmol/L was the reference standard for type 2 diabetes, and FPG between 6.1 and 6.9 mmol/L as impaired fasting glucose. PARTICIPANTS: 3645 adults (of whom 63% were women) recruited from two demographic surveillance study sites in urban and rural Malawi. This analysis excluded those who had a previous diagnosis of diabetes or had history of taking diabetes medication. RESULTS: HbA1c demonstrated excellent validity to detect FPG-defined diabetes, with an area under the receiver operating characteristic (AUROC) curve of 0.92 (95% CI 0.90 to 0.94). At HbA1c ≥6.5% (140 mg/dL), sensitivity was 78.7% and specificity was 94.0%. Subgroup AUROCs ranged from 0.86 for participants with anaemia to 0.94 for participants in urban Malawi. There were clinical and metabolic differences between participants with true diabetes versus false positives when HbA1c was ≥6.5% (140 mg/dL). CONCLUSIONS: The findings from this study provide justification to use HbA1c to detect type 2 diabetes. As HbA1c testing is substantially less burdensome to patients than either FPG testing or oral glucose tolerance testing, it represents a useful option for expanding access to diabetes care in sub-Saharan Africa.

Randomised controlled clinical trial of increased dose and frequency of albendazole and ivermectin on Wuchereria bancrofti microfilarial clearance in northern Malawi.

BACKGROUND: In Africa, albendazole and ivermectin are currently used in combination for annual mass drug administration (MDA) for lymphatic filariasis (LF) elimination. Rapid and sustained clearance is desirable for public health impact and elimination of LF. Increasing the dose and/or frequency of albendazole and ivermectin treatment may be more effective in clearing microfilariae than standard MDA. METHODS: We conducted a randomised controlled open label trial in northern Malawi comparing three modified treatment groups to standard dosage of ivermectin and albendazole in adults with confirmed circulating LF antigen and microfilaria. Participants were followed-up every 6 months for 2 years for repeat microfilarial counts and safety assessments. RESULTS: A total of 1851 adults were screened and 70 with microfilarial counts >80 microfilariae/ml were randomised. All treatment groups achieved a significant reduction of microfilariae levels by 12- and 24-months of follow-up. Doubling the standard dose and administering it twice yearly showed a non-significant tendency towards faster and more complete clearance. There were no serious adverse reactions. CONCLUSIONS: In this small study, all regimens effectively cleared microfilaria. Standard treatment may be adequate in settings like Malawi but not in all endemic settings and larger studies are required to demonstrate benefit of higher dosages. [ClinicalTrials.gov identifier: NCT01213576].