Assessment of non-tuberculosis abnormalities on digital chest x-rays with high CAD4TB scores from a tuberculosis prevalence survey in Zambia and South Africa.

BACKGROUND: Chest X-rays (CXRs) have traditionally been used to aid the diagnosis of TB-suggestive abnormalities. Using Computer-Aided Detection (CAD) algorithms, TB risk is quantified to assist with diagnostics. However, CXRs capture all other structural abnormalities. Identification of non-TB abnormalities in individuals with CXRs that have high CAD scores but don't have bacteriologically confirmed TB is unknown. This presents a missed opportunity of extending novel CAD systems' potential to simultaneously provide information on other non-TB abnormalities alongside TB. This study aimed to characterize and estimate the prevalence of non-TB abnormalities on digital CXRs with high CAD4TB scores from a TB prevalence survey in Zambia and South Africa. METHODOLOGY: This was a cross-sectional analysis of clinical data of participants from the TREATS TB prevalence survey conducted in 21 communities in Zambia and South Africa. The study included individuals aged ≥ 15 years who had high CAD4TB scores (score ≥ 70), but had no bacteriologically confirmed TB in any of the samples submitted, were not on TB treatment, and had no history of TB. Two consultant radiologists reviewed the images for non-TB abnormalities. RESULTS: Of the 525 CXRs reviewed, 46.7% (245/525) images were reported to have non-TB abnormalities. About 11.43% (28/245) images had multiple non-TB abnormalities, while 88.67% (217/245) had a single non-TB abnormality. The readers had a fair inter-rater agreement (r = 0.40). Based on anatomical location, non-TB abnormalities in the lung parenchyma (19%) were the most prevalent, followed by Pleura (15.4%), then heart & great vessels (6.1%) abnormalities. Pleural effusion/thickening/calcification (8.8%) and cardiomegaly (5%) were the most prevalent non-TB abnormalities. Prevalence of (2.7%) for pneumonia not typical of pulmonary TB and (2.1%) mass/nodules (benign/ malignant) were also reported. CONCLUSION: A wide range of non-TB abnormalities can be identified on digital CXRs among individuals with high CAD4TB scores but don't have bacteriologically confirmed TB. Adaptation of AI systems like CAD4TB as a tool to simultaneously identify other causes of abnormal CXRs alongside TB can be interesting and useful in non-faculty-based screening programs to better link cases to appropriate care.

Coverage and predictors of the uptake of the mass drug administration of praziquantel chemotherapy for schistosomiasis in a selected urban setting in Zambia.

The burden of schistosomiasis in Zambia has remained high over the years. The World Health Assembly recommended adequate mass drug administration coverage for schistosomiasis using Praziquantel chemotherapy for school-aged children and all at-risks adults. We aimed at investigating the coverage and the factors associated to the uptake for MDA for schistosomiasis in Ng'ombe township of Lusaka, Zambia. A cross-sectional survey was conducted in May and June 2021 via phone calls to the residents of Ng'ombe township. Commcare software was used in the conduct of the survey. Pearson's Chi-square test and multiple logistic regression were conducted using the STATA version 15.0. 769 study participants were randomly selected using systematic sampling, of which 76.3% were younger than 40 years, 64.9% were female, 64.4% were married, 56.3% had reached the secondary educational level and 51.9% were employed. Coverage for MDA for schistosomiasis in Ng'ombe township in 2018 was found to be 49.8% (95% CI: 46.2%-53.4%). Positive predictors of the MDA were prior knowledge of the occurrence of the MDA in 2018 (aOR: 2.892, p < 0.001) and believing that the provision of incentives like snacks was important during the MDA with PZQ in Ng'ombe township (aOR: 1.926, p = 0.001), whereas age (aOR:0.979, p = 0.009), marital status (aOR:0.620, p = 0.006), employment status (aOR:0.587, p = 0.001) were negative predictors of the MDA. Elimination of the burden of schistosomiasis in endemic settings needs the attainment of an optimum coverage and uptake during MDA with PZQ. Therefore, prior knowledge about an impending intervention and the provision of incentives like snacks during the intervention should be prioritized by MDA implementers, while background characteristics such as age, marital status, and employment status need to be taken into consideration when planning and promoting uptake in future MDAs.

Luna Virus and Helminths in Wild Mastomys natalensis in Two Contrasting Habitats in Zambia: Risk Factors and Evidence of Virus Dissemination in Semen.

Transmission dynamics and the maintenance of mammarenaviruses in nature are poorly understood. Using metagenomic next-generation sequencing (mNGS) and RT-PCR, we investigated the presence of mammarenaviruses and co-infecting helminths in various tissues of 182 Mastomys natalensis rodents and 68 other small mammals in riverine and non-riverine habitats in Zambia. The Luna virus (LUAV) genome was the only mammarenavirus detected (7.7%; 14/182) from M. natalensis. Only one rodent from the non-riverine habitat was positive, while all six foetuses from one pregnant rodent carried LUAV. LUAV-specific mNGS reads were 24-fold higher in semen than in other tissues from males. Phylogenetically, the viruses were closely related to each other within the LUAV clade. Helminth infections were found in 11.5% (21/182) of M. natalensis. LUAV-helminth co-infections were observed in 50% (7/14) of virus-positive rodents. Juvenility (OR = 9.4; p = 0.018; 95% CI: 1.47-59.84), nematodes (OR = 15.5; p = 0.001; 95% CI: 3.11-76.70), cestodes (OR = 10.8; p = 0.025; 95% CI: 1.35-86.77), and being male (OR = 4.6; p = 0.036; 95% CI: 1.10-18.90) were associated with increased odds of LUAV RNA detection. The role of possible sexual and/or congenital transmission in the epidemiology of LUAV infections in rodents requires further study, along with the implications of possible helminth co-infection.

Geospatial approach to investigate spatial clustering and hotspots of blood lead levels in children within Kabwe, Zambia.

BACKGROUND: Communities around Kabwe, Zambia are exposed to lead due to deposits from an old lead (Pb) and zinc (Zn) mining site. Children are particularly more vulnerable than adults, presenting with greatest risk of health complications. They have increased oral uptake due to their hand to mouth activities. Spatial analysis of childhood lead exposure is useful in identifying specific areas with highest risk of pollution. The objective of the current study was to use a geospatial approach to investigate spatial clustering and hotspots of blood lead levels in children within Kabwe. METHODS: We analysed existing data on blood lead levels (BLL) for 362 children below the age of 15 from Kabwe town. We used spatial autocorrelation methods involving the global Moran's I and local Getis-Ord Gi*statistic in ArcMap 10.5.1, to test for spatial dependency among the blood lead levels in children using the household geolocations. RESULTS: BLL in children from Kabwe are spatially autocorrelated with a Moran's Index of 0.62 (p < 0.001). We found distinct hotspots (mean 51.9 µg/dL) in communities close to the old lead and zinc-mining site, lying on its western side. Whereas coldspots (mean 7 µg/dL) where observed in areas distant to the mine and traced on the eastern side. This pattern suggests a possible association between observed BLL and distance from the abandoned lead and zinc mine, and prevailing winds. CONCLUSION: Using geocoded data for households, we found clustering of childhood blood lead and identified distinct hotspot areas with high lead levels for Kabwe town. The geospatial approach used is especially valuable in resource-constrained settings like Zambia, where the precise identification of high risk locations allows for the initiation of targeted remedial and treatment programs.

Biomonitoring of arsenic, cadmium and lead in two artisanal and small-scale gold mining areas in Zimbabwe.

People living and working in artisanal and small-scale gold mining (ASGM) areas are frequently exposed to elemental mercury (Hg), which is used for gold extraction. However, additional exposure to other toxic metals such as arsenic (As), cadmium (Cd) and lead (Pb) may result from mining-related activities and could be ingested via dust, water or food. In these areas, only limited biomonitoring data is available for toxic metals other than Hg. In particular, data about the exposure to As, Cd and Pb is unavailable for the Zimbabwean population. Therefore, we conducted a cross-sectional study in two ASGM areas in Zimbabwe to evaluate the internal exposure to these metals. In total, urine and blood samples from 207 people that identified themselves as miners were collected and analysed for As and Cd in urine as well as Pb in blood by GF-AAS. Median levels (interquartile ranges in µg/l) of As and Pb were 9.7 µg/l (4.0, 18.5) and 19.7 µg/l (12.5, 34.5), respectively. The 25th percentile and the median for Cd were below the limit of detection (0.5 µg/l); the 75th percentile was at 0.9 µg/l. The results were compared to reference values found for the general population in the USA and Germany, and a significant number of participants exceeded these values (As, 33 %; Cd, 27 %; Pb, 32 %), indicating a relevant exposure to toxic metals. Although not representative for the Zimbabwean population, our results demonstrate that the exposure to toxic metals is relevant for the public health in Zimbabwe and requires further investigation.

Modelling chronic malnutrition in Zambia: A Bayesian distributional regression approach.

BACKGROUND: The burden of child under-nutrition still remains a global challenge, with greater severity being faced by low- and middle-income countries, despite the strategies in the Sustainable Development Goals (SDGs). Globally, malnutrition is the one of the most important risk factors associated with illness and death, affecting hundreds of millions of pregnant women and young children. Sub-Saharan Africa is one of the regions in the world struggling with the burden of chronic malnutrition. The 2018 Zambia Demographic and Health Survey (ZDHS) report estimated that 35% of the children under five years of age are stunted. The objective of this study was to analyse the distribution, and associated factors of stunting in Zambia. METHODS: We analysed the relationships between socio-economic, and remote sensed characteristics and anthropometric outcomes in under five children, using Bayesian distributional regression. Georeferenced data was available for 25,852 children from two waves of the ZDHS, 31% observation were from the 2007 and 69% were from the 2013/14. We assessed the linear, non-linear and spatial effects of covariates on the height-for-age z-score. RESULTS: Stunting decreased between 2007 and 2013/14 from a mean z-score of 1.59 (credible interval (CI): -1.63; -1.55) to -1.47 (CI: -1.49; -1.44). We found a strong non-linear relationship for the education of the mother and the wealth of the household on the height-for-age z-score. Moreover, increasing levels of maternal education above the eighth grade were associated with a reduced variation of stunting. Our study finds that remote sensed covariates alone explain little of the variation of the height-for-age z-score, which highlights the importance to collect socio-economic characteristics, and to control for socio-economic characteristics of the individual and the household. CONCLUSIONS: While stunting still remains unacceptably high in Zambia with remarkable regional inequalities, the decline is lagging behind goal two of the SDGs. This emphasises the need for policies that help to reduce the share of chronic malnourished children within Zambia.

Bacteriological Quality and Heavy Metal Analysis of Packaged Water Produced in Lusaka, Zambia and Associated Quality Control Measures.

Many people in the world lack safe basic drinking water sources and rely on untreated water source. Packaged water can be considered as an alternative to other water sources if measures are put in place to ensure its safety for consumption. This study aimed to assess the bacteriological quality and heavy metal analysis of packaged water produced in Lusaka, Zambia and associated quality control measures. A cross-sectional study was conducted in May 2019 where 18 brands of packaged water were analyzed for total and fecal coliforms as well as concentrations of Lead, Chromium, and Cadmium. The study found that 33.5% of the packaged water produced in Lusaka did not comply with the standard for drinking water on bacteriological quality. We also found that the concentrations for Lead were <0.01 mg/l in all the 17 samples, thus compliant to WHO/ZABS standards. Concentrations of Chromium were between 0.002 and 0.62 mg/l and compliance to the standard was 11.8%. Concentrations for Cadmium were between 0.009 and 0.2 mg/l against the acceptable concentration of <0.003 mg/l. Most brands of the packaged water did not conform to the standards for drinking water.

Treatment outcomes and characteristics of HIV-2 patients compared to HIV-1 patients on an NNRTI-based first line art at the adult infectious diseases centre of the University Teaching Hospital (UTH) in Lusaka.

INTRODUCTION: the focus of antiretroviral therapy (ART) in Zambia has been on HIV-1. However, some patients are infected with HIV-2 or both. HIV-2 is resistant to non-nucleoside reverse transcriptase inhibitors (NNRTIs), drugs used for HIV-1. Therefore, this study sought to determine the seroprevalence of HIV-2 or dual infection in HIV infected individuals and compare the treatment outcomes associated with HIV subtype in patients taking NNRTI-based first line cART at the University Teaching Hospitals (UTH). METHODS: this was a cross- sectional study, we collected data from the Virological Impact of Switching from Efavirenz and Nevirapine based first-line cART regimens to Dolutegravir (VISEND) study being conducted at UTH. Ninety six individuals were included in the study. Descriptive and inferential statistics were performed. Logistic regression was used to assess the relationship between treatment outcomes and HIV type. RESULTS: the proportion of HIV 1 and 2 co-infected patients was 5.2% (95% CI 2%-12%). The mean age was 46 years ± 2 years with 60 (62.5%) being females. The median viral load was 1.3 log 10 copies/ml, IQR 0-1.7 log 10 copies/ml and the median absolute CD4+ T cell count increased from 231 to 463 cells/mm3 (p < 0.001) after being on cART for one year or more. The study did not report any associations between treatment outcomes and HIV type (p > 0.05). CONCLUSION: there is a small proportion of patients that are HIV 1 and 2 co-infected but are on an NNRTI-based cART regimen, drugs that are not active against HIV-2. This, however, does not seem to significantly affect the patient´s virological or immunological treatment outcome.

Proceedings from the CIHLMU Symposium 2020 on "eHealth: Trends and innovations".

Electronic Health (eHealth) is the use of information and communication technologies for health and plays a significant role in improving public health. The rapid expansion and development of eHealth initiatives allow researchers and healthcare providers to connect more effectively with patients. The aim of the CIHLMU Symposium 2020 was to discuss the current challenges facing the field, opportunities in eHealth implementation, to share the experiences from different healthcare systems, and to discuss future trends addressing the use of digital platforms in health. The symposium on eHealth explored how the health and technology sector must increase efforts to reduce the obstacles facing public and private investment, the efficacy in preventing diseases and improving patient quality of life, and the ethical and legal frameworks that influence the proper development of the different platforms and initiatives related to the field. This symposium furthered the sharing of knowledge, networking, and patient/user and practitioner experiences in low- and middle-income countries (LMIC) in both public and private sectors.

Factors associated with unfavourable tuberculosis treatment outcomes in Lusaka, Zambia, 2015: a secondary analysis of routine surveillance data.

INTRODUCTION: Focus has been put on strengthening surveillance systems in high tuberculosis (TB) burden countries, like Zambia, however inadequate information on factors associated with unfavourable TB treatment outcomes is generated from the system. We determined the proportion of tuberculosis treatment outcomes and their associated factors. METHODS: We defined unfavourable outcome as death, lost-to-follow-up, treatment-failure, or not-evaluated and favourable outcome as a patient cured or completed-treatment. We purposively selected a 1st level hospital, an urban-clinic and a peri-urban clinic. We abstracted data from TB treatment registers at these three health facilities, for all TB cases on treatment from 1st January to 31st December, 2015. We calculated proportions of treatment outcomes and analysed associations between unfavourable outcome and factors such as age, HIV status, health facility, and patient type, using univariate logistics regression. We used multivariable stepwise logistic regression to control for confounding and reported the adjusted odds ratios (AOR) and 95% confidence intervals (CI). RESULTS: We included a total of 1,724 registered TB patients, from one urban clinic 694 (40%), a 1st Level Hospital 654 (38%), and one peri-urban-clinic 276 (22%). Of the total patients, 43% had unfavourable outcomes. Of the total unfavourable outcomes, were recorded as treatment-failure (0.3%), lost-to-follow-up (5%), death (9%) and not evaluated (29%). The odds of unfavourable outcome were higher among patients > 59 years (AOR=2.9, 95%CI: 1.44-5.79), relapses (AOR=1.65, 95%CI: 1.15-2.38), patients who sought treatment at the urban clinic (AOR=1.76, 95%CI:1.27-2.42) and TB/HIV co-infected patients (AOR=1.56, 95%CI:1.11-2.19). CONCLUSION: Unfavourable TB treatment outcomes were high in the selected facilities. We recommend special attention to TB patients who are > 59 years old, TB relapses and TB / HIV co-infected. The national TB programme should strengthen close monitoring of health facilities in increasing efforts aimed at evaluating all the outcomes. Studies are required to identify and test interventions aimed at improving treatment outcomes.