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OBJECTIVE: To describe the mortality risks by fine strata of gestational age and birthweight among 230 679 live births in nine low- and middle-income countries (LMICs) from 2000 to 2017. DESIGN: Descriptive multi-country secondary data analysis. SETTING: Nine LMICs in sub-Saharan Africa, Southern and Eastern Asia, and Latin America. POPULATION: Liveborn infants from 15 population-based cohorts. METHODS: Subnational, population-based studies with high-quality birth outcome data were invited to join the Vulnerable Newborn Measurement Collaboration. All studies included birthweight, gestational age measured by ultrasound or last menstrual period, infant sex and neonatal survival. We defined adequate birthweight as 2500-3999 g (reference category), macrosomia as ≥4000 g, moderate low as 1500-2499 g and very low birthweight as <1500 g. We analysed fine strata classifications of preterm, term and post-term: ≥42+0 , 39+0 -41+6 (reference category), 37+0 -38+6 , 34+0 -36+6 ,34+0 -36+6 ,32+0 -33+6 , 30+0 -31+6 , 28+0 -29+6 and less than 28 weeks. MAIN OUTCOME MEASURES: Median and interquartile ranges by study for neonatal mortality rates (NMR) and relative risks (RR). We also performed meta-analysis for the relative mortality risks with 95% confidence intervals (CIs) by the fine categories, stratified by regional study setting (sub-Saharan Africa and Southern Asia) and study-level NMR (≤25 versus >25 neonatal deaths per 1000 live births). RESULTS: We found a dose-response relationship between lower gestational ages and birthweights with increasing neonatal mortality risks. The highest NMR and RR were among preterm babies born at <28 weeks (median NMR 359.2 per 1000 live births; RR 18.0, 95% CI 8.6-37.6) and very low birthweight (462.8 per 1000 live births; RR 43.4, 95% CI 29.5-63.9). We found no statistically significant neonatal mortality risk for macrosomia (RR 1.1, 95% CI 0.6-3.0) but a statistically significant risk for all preterm babies, post-term babies (RR 1.3, 95% CI 1.1-1.5) and babies born at 370 -386 weeks (RR 1.2, 95% CI 1.0-1.4). There were no statistically significant differences by region or underlying neonatal mortality. CONCLUSIONS: In addition to tracking vulnerable newborn types, monitoring finer categories of birthweight and gestational age will allow for better understanding of the predictors, interventions and health outcomes for vulnerable newborns. It is imperative that all newborns from live births and stillbirths have an accurate recorded weight and gestational age to track maternal and neonatal health and optimise prevention and care of vulnerable newborns.
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BACKGROUND: Over the last two decades, many countries have moved from malaria control toward malaria elimination. However, some sub-Saharan African countries, like Malawi, have recently seen a reversal in malaria control progress with reported increases in confirmed malaria cases. This may be the result of inadequate access to effective malaria control interventions by key population groups that perpetuate transmission. This study aimed to assess the barriers to accessing malaria treatment among school-aged children (SAC) in Malawi. METHODS: A qualitative study was conducted between September and October 2020, where data were gathered in rural Malawi using free-listing interviews, key-informant interviews, semi-structured interviews and focus group discussions. Purposively sampled participants included SAC, parents of SAC, health workers and key stakeholders at community and district levels. Interviews were digitally recorded and transcribed verbatim. Data were organized using NVivo 12 software and analysed using the thematic method. RESULTS: The study recruited 252 participants, with 156 being SAC, equally divided between boys and girls. Health system barriers to malaria treatment included long waiting hours and queues at clinics, frequent stock-outs of medical supplies, and travel time to the facility. Provider barriers included negative attitude and limited service hours. Individual and cultural barriers included fear of malaria tests and beliefs associating witchcraft as the best treatment for malaria. In addition, COVID-19-related barriers included the inability to follow preventive measures, a shift in focus from malaria to COVID-19, and fear of contracting COVID-19 and/or being tested for COVID-19 at the facility. CONCLUSIONS: This study shows most of the barriers to accessing malaria treatment among SAC are similar to those experienced by other population groups. Furthermore, COVID-19 adversely affected SAC's access to treatment. Interventions that support SAC access to prompt diagnosis and treatment are urgently needed to improve the effective control of malaria.
Subject(s)
COVID-19 , Malaria , Male , Female , Humans , Child , Malawi/epidemiology , COVID-19/epidemiology , COVID-19/therapy , Fear , Focus Groups , Malaria/drug therapy , Malaria/prevention & controlABSTRACT
BACKGROUND: The complex interaction between malaria and undernutrition leads to increased mortality and morbidity rate among young children in malaria-endemic regions. Results from previous interventions suggest that improving nutritional status of young children may reduce the burden of malaria. This study tested a hypothesis that provision of lipid-based nutrient supplements (LNS) or corn-soy blend (CSB) supplementation to 6-18-month-old children in Malawi would reduce the prevalence of asymptomatic malaria among them. METHODS: A total of 840 6-month-old children were enrolled in a randomized trial. The participants received 12-month supplementation with three different daily dietary supplementations: CSB, soy-LNS, or milk-LNS, and one control group without supplementation. The prevalence rate of asymptomatic Plasmodium falciparum was determined by real-time PCR from the participant's dried blood spots (DBS) collected at the baseline and every 3 months. The global null hypothesis was tested using modified Poisson regression to estimate the prevalence ratio (PR) between the control group and three intervention groups at all ages combined. All the models were adjusted for malaria at baseline, season of DBS sample collection, site of enrolment, and household asset Z-score. RESULTS: All children combined, the prevalence of P. falciparum was 14.1% at enrollment, 8.7% at 9 months, 11.2% at 12 months, 13.0% at 15 months and 22.4% at 18 months of age. Among all samples that were taken after enrolment, the prevalence was 12.1% in control group, 12.2% in milk-LNS, 14.0% in soy-LNS, and 17.2% in CSB group. Compared to children in the control group the prevalence ratio of positive malaria tests was 1.19 (95% CI 0.81-1.74; P = 0.372) in the milk-LNS group, 1.32 (95% CI 0.88-1.96; P = 0.177) in the soy-LNS group and 1.72 (95% CI 1.19-2.49; P = 0.004) in the CSB group. CONCLUSION: The study findings do not support a hypothesis that LNS or CSB supplementation would reduce the prevalence of asymptomatic malaria among Malawian children. In contrast, there was a signal of a possible increase in malaria prevalence among children supplemented with CSB.
Subject(s)
Malaria, Falciparum , Malaria , Humans , Child , Child, Preschool , Infant , Malawi/epidemiology , Prevalence , Dietary Supplements , Malaria/epidemiology , Malaria/prevention & control , Malaria, Falciparum/epidemiology , Malaria, Falciparum/prevention & control , Zea maysABSTRACT
Low birth weight predisposes to the development of hypertension in middle- and high-income countries. We examined the relation of early life length-for-age score (Z-score) on cardiovascular function in young adults in Malawi, a low-income country. Capture of supine, seated, and standing brachial pulse waveforms (Mobil-O-Graph) were performed in 223 females and 152 males (mean age 21 years), and analyzed according to the length-for-age Z-score tertiles during the first month of life. Plasma LDL cholesterol in young adulthood was slightly lower in the lowest versus highest tertile. Otherwise, blood hemoglobin and plasma chemistry were similar in all tertiles. Irrespective of posture, blood pressure, forward and backward wave amplitudes, and pulse wave velocity were corresponding in all tertiles. In the three postures, the lowest tertile presented with 4.5% lower systemic vascular resistance than the highest tertile (p = 0.005), and 4.4% and 5.5% higher cardiac output than the middle and highest tertiles, respectively (p < 0.01). Left cardiac work was 6.8% and 6.9% higher in the lowest tertile than in the middle and highest tertiles, respectively (p < 0.01). To conclude, in a low-income environment, low length-for-age Z-score after birth predicted hyperdynamic circulation at 21 years of age without changes in blood pressure and metabolic variables.
Subject(s)
Parturition , Pulse Wave Analysis , Female , Male , Young Adult , Humans , Pregnancy , Adult , Infant , Malawi , Blood Pressure , Heart RateABSTRACT
OBJECTIVE: We aimed to understand the mortality risks of vulnerable newborns (defined as preterm and/or born weighing smaller or larger compared to a standard population), in low- and middle-income countries (LMICs). DESIGN: Descriptive multi-country, secondary analysis of individual-level study data of babies born since 2000. SETTING: Sixteen subnational, population-based studies from nine LMICs in sub-Saharan Africa, Southern and Eastern Asia, and Latin America. POPULATION: Live birth neonates. METHODS: We categorically defined five vulnerable newborn types based on size (large- or appropriate- or small-for-gestational age [LGA, AGA, SGA]), and term (T) and preterm (PT): T + LGA, T + SGA, PT + LGA, PT + AGA, and PT + SGA, with T + AGA (reference). A 10-type definition included low birthweight (LBW) and non-LBW, and a four-type definition collapsed AGA/LGA into one category. We performed imputation for missing birthweights in 13 of the studies. MAIN OUTCOME MEASURES: Median and interquartile ranges by study for the prevalence, mortality rates and relative mortality risks for the four, six and ten type classification. RESULTS: There were 238 203 live births with known neonatal status. Four of the six types had higher mortality risk: T + SGA (median relative risk [RR] 2.6, interquartile range [IQR] 2.0-2.9), PT + LGA (median RR 7.3, IQR 2.3-10.4), PT + AGA (median RR 6.0, IQR 4.4-13.2) and PT + SGA (median RR 10.4, IQR 8.6-13.9). T + SGA, PT + LGA and PT + AGA babies who were LBW, had higher risk compared with non-LBW babies. CONCLUSIONS: Small and/or preterm babies in LIMCs have a considerably increased mortality risk compared with babies born at term and larger. This classification system may advance the understanding of the social determinants and biomedical risk factors along with improved treatment that is critical for newborn health.
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BACKGROUND: Control of malaria parasite transmission can be enhanced by understanding which human demographic groups serve as the infectious reservoirs. Because vector biting can be heterogeneous, some infected individuals may contribute more to human-to-mosquito transmission than others. Infection prevalence peaks in school-age children, but it is not known how often they are fed upon. Genotypic profiling of human blood permits identification of individual humans who were bitten. The present investigation used this method to estimate which human demographic groups were most responsible for transmitting malaria parasites to Anopheles mosquitoes. It was hypothesized that school-age children contribute more than other demographic groups to human-to-mosquito malaria transmission. METHODS: In a region of moderate-to-high malaria incidence in southeastern Malawi, randomly selected households were surveyed to collect human demographic information and blood samples. Blood-fed, female Anopheles mosquitoes were sampled indoors from the same houses. Genomic DNA from human blood samples and mosquito blood meals of human origin was genotyped using 24 microsatellite loci. The resultant genotypes were matched to identify which individual humans were sources of blood meals. In addition, Plasmodium falciparum DNA in mosquito abdomens was detected with polymerase chain reaction. The combined results were used to identify which humans were most frequently bitten, and the P. falciparum infection prevalence in mosquitoes that resulted from these blood meals. RESULTS: Anopheles females selected human hosts non-randomly and fed on more than one human in 9% of the blood meals. Few humans contributed most of the blood meals to the Anopheles vector population. Children ≤ 5 years old were under-represented in mosquito blood meals while older males (31-75 years old) were over-represented. However, the largest number of malaria-infected blood meals was from school age children (6-15 years old). CONCLUSIONS: The results support the hypothesis that humans aged 6-15 years are the most important demographic group contributing to the transmission of P. falciparum to the Anopheles mosquito vectors. This conclusion suggests that malaria control and prevention programmes should enhance efforts targeting school-age children and males.
Subject(s)
Anopheles , Blood , Host-Seeking Behavior , Malaria, Falciparum , Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Anopheles/parasitology , DNA/blood , Genotype , Malaria/blood , Malaria/parasitology , Malaria/prevention & control , Malaria/transmission , Malaria, Falciparum/blood , Malaria, Falciparum/parasitology , Malaria, Falciparum/prevention & control , Malaria, Falciparum/transmission , Meals , Mosquito Vectors/parasitology , Plasmodium falciparum/genetics , Blood/parasitology , MalawiABSTRACT
BACKGROUND: Body composition can be measured by several methods, each with specific benefits and disadvantages. Bioelectric impedance offers a favorable balance between accuracy, cost and ease of measurement in a range of settings. In this method, bioelectric measurements are converted to body composition measurements by prediction equations specific to age, population and bioimpedance device. Few prediction equations exist for populations in low-resource settings. We formed a prediction equation for total body water in Malawian adolescents using deuterium dilution as reference. METHODS: We studied 86 boys and 92 girls participating in the 11-14-year follow-up of the Lungwena Antenatal Intervention Study, a randomized trial of presumptive infection treatment among pregnant women. We measured body composition by Seca m515 bioimpedance analyser. Participants ingested a weight-standardized dose of deuterium oxide, after which we collected saliva at baseline, at 3 and 4 h post-ingestion, measured deuterium concentration using Fourier-transform infrared spectroscopy and calculated total body water. We formed predictive equations for total body water using anthropometrics plus resistance and reactance at a range of frequencies, applying multiple regression and repeated cross-validation in model building and in prediction error estimation. RESULTS: The best predictive model for percentage total body water (TBW %) was 100*(1.11373 + 0.0037049*height (cm)2/resistance(Ω) at 50 kHz- 0.25778*height(m)- 0.01812*BMI(kg/m2)- 0.02614*female sex). Calculation of absolute TBW (kg) by multiplying TBW (%) with body weight had better predictive power than a model directly constructed to predict absolute total body water (kg). This model explained 96.4% of variance in TBW (kg) and had a mean prediction error of 0.691 kg. Mean bias was 0.01 kg (95% limits of agreement -1.34, 1.36) for boys and -0.01 kg (1.41, 1.38) for girls. CONCLUSIONS: Our equation provides an accurate, cost-effective and participant-friendly body composition prediction method among adolescents in clinic-based field studies in rural Africa, where electricity is available.
Subject(s)
Body Composition , Body Water , Pregnancy , Male , Humans , Female , Adolescent , Deuterium , Electric Impedance , Anthropometry/methods , Indicator Dilution TechniquesABSTRACT
Maternal malaria and infections during pregnancy are risk factors for fetal growth restriction. We assessed the impact of preventive treatment in pregnancy on maternal malaria and fetal growth. Between 2003 and 2006, we enrolled 1,320 pregnant Malawian women, 14-26 gestation weeks, in a randomized trial and treated them with two doses of sulfadoxine-pyrimethamine (SP, control) at enrollment and between 28-34 gestation weeks; with monthly SP from enrollment until 37 gestation weeks; or with monthly SP and azithromycin twice, at enrollment and between 28 and 34 gestation weeks (AZI-SP). Participants were seen at 4-week intervals until 36 completed gestation weeks and weekly thereafter. At each visit, we collected dried blood spots for real-time polymerase chain reaction diagnosing of malaria parasitemia and, in a random subgroup of 341 women, we measured fetal biparietal diameter and femur length with ultrasound. For the monthly SP versus the control group, the odds ratios (OR) (95% CI) of malaria parasitemia during the second, third, and both trimesters combined were 0.79 (0.46-1.37), 0.58 (0.37-0.92), and 0.64 (0.42-0.98), respectively. The corresponding ORs for the AZI-SP versus control group were 0.47 (0.26-0.84), 0.51 (0.32-0.81), and 0.50 (0.32-0.76), respectively. Differences between the AZI-SP and the monthly SP groups were not statistically significant. The interventions did not affect fetal biparietal diameter and femur length growth velocity. The results suggest that preventive maternal treatment with monthly SP reduced malaria parasitemia during pregnancy in Malawi and that the addition of azithromycin did not provide much additional antimalarial effect.
Subject(s)
Antimalarials , Malaria , Pregnancy Complications, Parasitic , Female , Pregnancy , Humans , Azithromycin/therapeutic use , Parasitemia/drug therapy , Pregnancy Complications, Parasitic/prevention & control , Pyrimethamine/therapeutic use , Malaria/prevention & control , Antimalarials/therapeutic use , Drug Combinations , Fetal DevelopmentABSTRACT
Malaria remains a threat to public health in Malawi. It is well acknowledged that malaria research and robust evidence can have an impact on malaria policy and practice, resulting in positive population health gains. We report policy-relevant research contributions that the Malawi International Center of Excellence for Malaria Research (ICEMR) in partnership with local and international collaborators has made. Findings from our ICEMR studies have shown that long-lasting insecticide-treated bed nets (LLINs) impregnated with piperonyl butoxide reduced mosquito blood feeding more compared with conventional LLINs. On the other hand, we showed that few LLINs are maintained up to the end of their 3-year life span, and that older nets are less effective. These results support the policy change decisions by the Malawi National Malaria Control Program to switch from conventional LLINs to piperonyl butoxide LLINs, and to conduct mass LLIN distribution campaigns every 2 years. Our studies on epidemiological patterns of malaria infection showed that school-age children have higher malaria infection rates and lower use of control measures compared with younger children and adults. These findings added to the evidence base that influenced the National Malaria Control Program to endorse school-based malaria interventions as part of its national policy. Research supported by the Malawi ICEMR is contributing to in-country policy decisions and to the implementation of evidence-based interventions. Through our long-term studies we intend to continue providing practical and policy-relevant evidence necessary, ultimately, to eliminate malaria infection in Malawi.
Subject(s)
Insecticide-Treated Bednets , Malaria , Adult , Animals , Child , Health Policy , Humans , Insecticide Resistance , Malaria/epidemiology , Malaria/prevention & control , Malawi/epidemiology , Mosquito Control/methods , Piperonyl ButoxideABSTRACT
Despite the scale-up of interventions against malaria over the past decade, this disease remains a leading threat to health in Malawi. To evaluate the epidemiology of both Plasmodium falciparum infection and malaria disease, the Malawi International Center of Excellence for Malaria Research (ICEMR) has developed and implemented diverse and robust surveillance and research projects. Descriptive studies in ICEMR Phase 1 increased our understanding of the declining effectiveness of long-lasting insecticidal nets (LLINs), the role of school-age children in malaria parasite transmission, and the complexity of host-parasite interactions leading to disease. These findings informed the design of ICEMR Phase 2 to test hypotheses about LLIN use and effectiveness, vector resistance to insecticides, demographic targets of malaria control, patterns and causes of asymptomatic to life-threatening disease, and the impacts of RTS,S vaccination plus piperonyl butoxide-treated LLINs on infection and disease in young children. These investigations are helping us to understand mosquito-to-human and human-to-mosquito transmission in the context of Malawi's intransigent malaria problem.
Subject(s)
Insecticide-Treated Bednets , Insecticides , Malaria , Animals , Child , Child, Preschool , Humans , Insecticide Resistance , Insecticides/pharmacology , Insecticides/therapeutic use , Malaria/epidemiology , Malaria/prevention & control , Malawi/epidemiology , Mosquito Control , Mosquito Vectors/parasitology , Piperonyl ButoxideABSTRACT
Background Cardiovascular risk is higher in men than in women, but little information exists about sex-related differences in cardiovascular function from low-income countries. We compared hemodynamics between sexes in rural Malawi in a cohort followed up since their birth. Methods and Results Supine, seated, and standing hemodynamics were recorded from 251 women and 168 men (mean age, 21 years; body mass index, 21 kg/m2) using oscillometric brachial waveform analyses (Mobil-O-Graph). The results were adjusted for estimated glomerular filtration rate, and plasma potassium, lipids, and glucose. Men had higher brachial and aortic systolic blood pressure and stroke index regardless of posture (P<0.001), and higher upright but similar supine diastolic blood pressure than women. Regardless of posture, heart rate was lower in men (P<0.001), whereas cardiac index did not differ between sexes. Women presented with lower supine and standing systemic vascular resistance index (P<0.001), whereas supine-to-standing increase in vascular resistance (P=0.012) and decrease in cardiac index (P=0.010) were higher in women. Supine left cardiac work index was similar in both sexes, whereas standing and seated left cardiac work index was higher in men than in women (P<0.001). Conclusions In young Malawian adults, men had higher systolic blood pressure, systemic vascular resistance, and upright cardiac workload, whereas women presented with higher posture-related changes in systemic vascular resistance and cardiac output. These findings show systematic sex-related differences in cardiovascular function in a cohort from a low-income country with high exposure to prenatal and postnatal malnutrition and infectious diseases.
Subject(s)
Hemodynamics , Posture , Adult , Blood Pressure/physiology , Female , Heart Rate/physiology , Hemodynamics/physiology , Humans , Malawi/epidemiology , Male , Posture/physiology , Young AdultABSTRACT
OBJECTIVE: To assess whether intermittent preventive treatment of pregnant women (IPTp) with sulfadoxine-pyrimethamine (SP) and azithromycin (AZI) in a malaria-endemic area leads to sustained gains in linear growth and development in their offspring. DESIGN: Follow-up study of a randomised trial. SETTING: Mangochi District in rural southern Malawi. PARTICIPANTS: 1320 pregnant women and their offspring. INTERVENTIONS: IPTp monthly with SP and twice with AZI (AZI-SP group), monthly with SP but no AZI (monthly SP), or twice with SP (control). No intervention was given to children. MAIN OUTCOME MEASURES: Cognitive performance using Raven's Coloured Progressive Matrices (CPM) at 13 years of age; mean height and height-for-age Z-score (HAZ), cumulative incidence and prevalence of stunting (HAZ <-2); weight, body mass index, mid-upper-arm circumference and head circumference. RESULTS: At approximately 13 years of age, the mean CPM score was 14.3 (SD 3.8, range 6-29, maximum 36), with no differences between groups. Children in the AZI-SP group were on average 0.4 cm (95% CI -0.9 to 1.7, p=0.6) taller than those in the control group. For cumulative incidence of stunting, the HR in the AZI-SP group was 0.72 (95% CI 0.61 to 0.84, p<0.001) compared with the control and 0.76 (95% CI 0.65 to 0.90, p<0.001) compared with the monthly SP groups. There was no intergroup difference in stunting prevalence or anthropometric measurements. CONCLUSIONS: In rural Malawi, maternal intensified infection control during pregnancy reduces offspring's cumulative incidence of ever being stunted by 13 years of age. In this study, there was no evidence of a positive impact on cognitive performance. TRIAL REGISTRATION NUMBER: NCT00131235.
Subject(s)
Antimalarials , Pregnancy Complications, Parasitic , Anti-Bacterial Agents/therapeutic use , Antimalarials/therapeutic use , Azithromycin , Child , Drug Combinations , Female , Follow-Up Studies , Growth Disorders/drug therapy , Growth Disorders/epidemiology , Growth Disorders/prevention & control , Humans , Pregnancy , Pregnancy Complications, Parasitic/drug therapy , Pregnancy Complications, Parasitic/epidemiology , Pregnancy Complications, Parasitic/prevention & controlABSTRACT
As countries of sub-Saharan Africa expand irrigation to improve food security and foster economic growth, it is important to quantify the malaria risk associated with this process. Irrigated ecosystems can be associated with increased malaria risk, but this relationship is not fully understood. We studied this relationship at the Bwanje Valley Irrigation Scheme (800 hectares) in Malawi. Household prevalence of malaria and indoor Anopheles density were quantified in two cross-sectional studies in 2016 and 2017 (5,829 residents of 1,091 households). Multilevel logistic regression was used to estimate the association between distance to the irrigation scheme and malaria infection and mosquito density. The prevalence of malaria infection was 50.2% (2,765/5,511) by histidine-rich protein 2-based malaria rapid diagnostic tests and 30.1% (1,626/5,403) by microscopy. Individuals residing in households within 3 km of the scheme had significantly higher prevalence of infection (adjusted odds ratio [aOR] = 1.41; 95% confidence interval [CI] 1.18, 1.68); school-aged children had the highest prevalence among age groups (aOR = 1.34; 95% CI 1.11, 1.63). Individuals who reported bed net use, and households with higher socioeconomic status and higher level of education for household head or spouse, had lower odds of malaria infection. Female Anopheles mosquitoes (2,215 total; Anopheles arabiensis, 90.5%, Anopheles funestus, 9.5%) were significantly more abundant in houses located within 1.5 km of the scheme. Proximity of human dwellings to the irrigation scheme increased malaria risk, but higher household wealth index reduced risk. Therefore, multisectoral approaches that spur economic growth while mitigating increased malaria transmission are needed for people living close to irrigated sites.
Subject(s)
Agricultural Irrigation , Anopheles/growth & development , Malaria/epidemiology , Malaria/etiology , Mosquito Vectors/growth & development , Residence Characteristics , Adolescent , Adult , Animals , Child , Child, Preschool , Cross-Sectional Studies , Family Characteristics , Female , Humans , Insecticide-Treated Bednets , Malaria/transmission , Malawi/epidemiology , Male , Prevalence , Rain , Risk Factors , Seasons , Socioeconomic Factors , Young AdultABSTRACT
Three human protoparvoviruses, bufavirus (BuV), tusavirus (TuV) and cutavirus (CuV), have recently been discovered in diarrheal stool. BuV has been associated with diarrhea and CuV with cutaneous T-cell lymphoma, but there are hardly any data for TuV or CuV in stool or respiratory samples. Hence, using qPCR and IgG enzyme immunoassays, we analyzed 1072 stool, 316 respiratory and 445 serum or plasma samples from 1098 patients with and without gastroenteritis (GE) or respiratory-tract infections (RTI) from Finland, Latvia and Malawi. The overall CuV-DNA prevalences in stool samples ranged between 0-6.1% among our six patient cohorts. In Finland, CuV DNA was significantly more prevalent in GE patients above rather than below 60 years of age (5.1% vs 0.2%). CuV DNA was more prevalent in stools among Latvian and Malawian children compared with Finnish children. In 10/11 CuV DNA-positive adults and 4/6 CuV DNA-positive children with GE, no known causal pathogens were detected. Interestingly, for the first time, CuV DNA was observed in two nasopharyngeal aspirates from children with RTI and the rare TuV in diarrheal stools of two adults. Our results provide new insights on the occurrence of human protoparvoviruses in GE and RTI in different countries.
Subject(s)
DNA, Viral/genetics , Gastrointestinal Diseases/virology , Parvoviridae Infections/epidemiology , Parvoviridae Infections/virology , Parvovirus/genetics , Respiratory Tract Diseases/virology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cohort Studies , DNA, Viral/analysis , Feces/virology , Female , Finland/epidemiology , Gastrointestinal Diseases/epidemiology , Humans , Infant , Latvia/epidemiology , Malawi/epidemiology , Male , Middle Aged , Nasopharynx/virology , Parvoviridae Infections/blood , Parvovirus/classification , Phylogeny , Respiratory Tract Diseases/blood , Respiratory Tract Diseases/epidemiology , Young AdultABSTRACT
BACKGROUND: Malawi is a malaria-endemic country and approximately 6 million cases are reported annually. Improving knowledge of malaria causes and symptoms, and the overall perception towards malaria and its preventive measures is vital for malaria control. The current study investigated the levels of knowledge of the causes, symptoms and prevention of malaria among Malawian women. METHODS: Data from the 2017 wave of the Malawi Malaria Indicator Survey (MMIS) were analysed. In total, 3422 women of reproductive age (15-49 years) were sampled and analysed. The levels of women's knowledge about: (1) causes of malaria; (2) symptoms of malaria; and, (3) preventive measures were assessed. The tertiles of the composite score were used as the cut-offs to categorize the levels of knowledge as 'low', 'medium' and 'high'. Multinomial logistic regression models were constructed to assess the independent factors while taking into account the complex survey design. RESULTS: Approximately 50% of all respondents had high levels of knowledge of causes, symptoms and preventive measures. The high level of knowledge was 45% for rural women and 55% for urban dwellers. After adjusting for the a wide range of factors, women of age group 15-19 years adjusted odds ratio ((aOR): 2.58; 95% Confidence Interval (CI) 1.69-3.92), women with no formal education (aOR: 3.73; 95% CI 2.20-6.33), women whose household had no television (aOR: 1.50; 95% CI 1.02-2.22), women who had not seen/heard malaria message (aOR: 1.53; 95% CI 1.20-1.95), women of Yao tribe (aOR: 1.95; 95% CI 1.10-3.46), and women from rural areas had low levels of knowledge about the causes of malaria, symptoms of malaria and preventive measures. Additionally, the results also showed that women aged 15-19 years (beta [ß] = - 0.73, standard error [SE] = 0.12); P < .0001, women with no formal education (ß = - 1.17, SE = 0.15); P < .0001, women whose household had no radio (ß = - 0.15, SE = 0.0816); P = 0.0715 and women who had not seen or heard malaria message (ß = - 0.41, SE = 0.07); P < .0001 were likely to have a lower knowledge score. CONCLUSIONS: The levels of malaria knowledge were reported to be unsatisfactory among adult women, underscoring the need to scale up efforts on malaria education. Beside insecticide-treated bed nets (ITNs) and prompt diagnosis, malaria can be best managed in Malawi by increasing knowledge of malaria causes, and symptoms especially for younger women, women with no formal education, women whose households have no media, women from Yao tribes, and rural dwellers.
Subject(s)
Communicable Disease Control , Health Knowledge, Attitudes, Practice , Malaria/psychology , Mosquito Control , Adolescent , Adult , Animals , Female , Humans , Malaria/etiology , Malaria/prevention & control , Malawi , Middle Aged , Young AdultABSTRACT
Introduction: Collecting blood from voluntary non-remunerated blood donors from low risk populations is a key strategy for blood safety. Identifying such populations involves analysis of population and blood donor data to identify risk factors for transfusion transmissible infections (TTIs). There are no recent seroprevalence statistics for blood donors in Malawi. This study fills this gap by describing characteristics of blood donors, trend of annual prevalence of HIV, HBV, HCV and syphilis and factors associated with each TTI. Methods: Retrospective analysis of blood donors' records in the MBTS database from 2011 to 2015 was undertaken. Summary statistics were performed to describe characteristics of the blood donors. Univariable and multivariable logistic regression analyses were performed to determine association between prevalence of infections and socio-demographic factors. Time trend analysis was done to assess changes in prevalence. P-value <0.05 was considered statistically significant. Results: The number of blood donors screened over the 5 year period was 125,893. The mean number of donors donating blood per year was 39, 289; median age was 19 years; 82% were male, 87% single and 72% students and56% were repeat blood donors. Overall prevalence of each TTI decreased. The 2015 prevalence was: 3.6% for HBV; 1.9% for HIV; 2.6% for Syphilis and 1.0% for HCV while the 2011 prevalence was 4.7% for HBV; 3.5% for HIV 3.2% for syphilis and 2.4% for HCV.Repeat blood donors had significantly lower prevalence of TTIs than first time donors. Females were associated with lower risk for HBV, HCV and syphilis. Age ≥25 years and being out of school were associated with HIV. Age ≥25 years was associated with reduced risk for HCV and being self-employed and married were each associated with syphilis. Conclusion: The typical blood donor is a young single male student. Repeat blood donation improves safety of the blood supply.
Subject(s)
Blood Donors/statistics & numerical data , HIV Infections/epidemiology , Hepatitis B/epidemiology , Hepatitis C/epidemiology , Syphilis/epidemiology , Transfusion Reaction/epidemiology , Adolescent , Blood Safety , Female , HIV Infections/diagnosis , Hepatitis B/diagnosis , Hepatitis C/diagnosis , Humans , Malawi/epidemiology , Male , Middle Aged , Retrospective Studies , Seroepidemiologic Studies , Young AdultABSTRACT
AIM: Despite high pathogen burden and malnutrition in low-income settings, knowledge on relationship between asymptomatic viral or parasitic infections, nutrition and growth is insufficient. We studied these relationships in a cohort of six-month-old Malawian infants. METHODS: As part of a nutrient supplementation trial for 12 months, we documented disease symptoms of 840 participant daily and anthropometric measurements every three months. Stool specimens were collected every six months and analysed for Giardia lamblia, Cryptosporidium species and enterovirus, rotavirus, norovirus, parechovirus and rhinovirus using polymerase chain reaction (PCR). The prevalence of the microbes was compared to the children's linear growth and the dietary. RESULTS: The prevalence of the microbes was similar in every intervention group. All age groups combined, children negative for G. lamblia had a mean standard deviation (SD) of -0.01 (0.49) change in length-for-age Z-score (LAZ), compared to -0.12 (0.045) among G. lamblia positive children (difference -0.10, 95% CI -0.21 to -0.00, p = 0.047). The LAZ change difference was also statistically significant (p = 0.042) at age of 18-21 months but not at the other time points. CONCLUSION: Asymptomatic G. lamblia infection was mainly associated with growth reduction in certain three-month periods. The result refers to the chronic nature of G. lamblia infection.
Subject(s)
Feces/parasitology , Giardia lamblia/isolation & purification , Giardiasis/complications , Growth Disorders/parasitology , Asymptomatic Infections/epidemiology , Dietary Supplements , Feces/virology , Female , Giardiasis/epidemiology , Growth Disorders/diet therapy , Growth Disorders/virology , Humans , Infant , Malawi/epidemiology , MaleABSTRACT
AIM: Intermittent preventive treatment in pregnancy (IPTp) with azithromycin and monthly sulfadoxine-pyrimethamine increased the mean child weight, mid-upper arm and head circumference at four weeks of age in a rural low-income setting. Now we assess for how long these gains were sustained during 0-5 years of age. METHODS: We enrolled 1320 pregnant Malawian women in a randomized trial and treated them with two doses of sulfadoxine-pyrimethamine (control) or monthly sulfadoxine-pyrimethamine as IPTp against malaria, or monthly sulfadoxine-pyrimethamine and two doses of azithromycin (AZI-SP) as IPTp against malaria and reproductive tract infections. Child weight, mid-upper arm circumference, head circumference and weight-for-height Z-score were recorded at one, six, 12, 24, 36, 48, and 60 months. RESULTS: Throughout follow-up, the mean child weight was approximately 100 g higher (difference in means 0.12 kg, 95% CI 0.04-0.20, P = 0.003 at one month; 0.19 kg, 95% CI 0.05-0.33, P = 0.007, at six months), mean head circumference 2 mm larger (0.3 cm, 95% CI 0.1 to 0.5, P = 0.004 at one month) and the cumulative incidence of underweight by five years of age was lower (hazard ratio 0.74, 95% CI 0.60 to 0.90, P = 0.002) in the AZI-SP group than in the control group. The 2 mm difference in the mean mid-upper arm circumference at one month (0.2 cm, 95% CI 0.0 to 0.3, P = 0.007) disappeared after three years of age. There was no difference in mean weight-for-height Z-score at any time point. CONCLUSION: In Malawi, IPTp with azithromycin and monthly sulfadoxine-pyrimethamine has a modest, 3-5-year positive impact on child weight, mid-upper arm circumference and head circumference, but not on weight-for-height Z-score.
Subject(s)
Arm/anatomy & histology , Azithromycin/administration & dosage , Birth Weight/drug effects , Head/anatomy & histology , Malaria/prevention & control , Pyrimethamine/administration & dosage , Respiratory Tract Infections/prevention & control , Sulfadoxine/administration & dosage , Adult , Anti-Bacterial Agents/administration & dosage , Antimalarials/administration & dosage , Child , Child, Preschool , Drug Combinations , Female , Follow-Up Studies , Humans , Incidence , Infant , Infant, Newborn , Malaria/epidemiology , Malawi , Male , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/prevention & control , Pregnancy Complications, Parasitic/epidemiology , Pregnancy Complications, Parasitic/prevention & control , Respiratory Tract Infections/epidemiologyABSTRACT
BACKGROUND: Although poor complementary feeding is associated with poor child growth, nutrition interventions only have modest impact on child growth, due to high burden of infections. We aimed to assess the association of malaria with linear growth, hemoglobin, iron status, and development in children aged 6-18 months in a setting of high malaria and undernutrition prevalence. METHODS: Prospective cohort study, conducted in Mangochi district, Malawi. We enrolled six-months-old infants and collected weekly data for 'presumed' malaria, diarrhea, and acute respiratory infections (ARI) until age 18 months. Change in length-for-age z-scores (LAZ), stunting, hemoglobin, iron status, and development were assessed at age 18 months. We used ordinary least squares regression for continuous outcomes and modified Poisson regression for categorical outcomes. RESULTS: Of the 2723 children enrolled, 2016 (74.0%) had complete measurements. The mean (standard deviation) incidences of 'presumed' malaria, diarrhea, and ARI, respectively were: 1.4 (2.0), 4.6 (10.1), and 8.3 (5.0) episodes/child year. Prevalence of stunting increased from 27.4 to 41.5% from 6 to 18 months. 'Presumed' malaria incidence was associated with higher risk of stunting (risk ratio [RR] = 1.04, 95% confidence interval [CI] = 1.01 to 1.07, p = 0.023), anemia (RR = 1.02, 95%CI = 1.00 to 1.04, p = 0.014) and better socio-emotional scores (B = - 0.21, 95%CI = - 0.39 to - 0.03, p = 0.041), but not with change in LAZ, haemoglobin, iron status or other developmental outcomes. Diarrhea incidence was associated with change in LAZ (B = - 0.02; 95% CI = - 0.03 to - 0.01; p = 0.009), stunting (RR = 1.02; 95% CI = 1.01 to 1.03; p = 0.005), and slower motor development. ARI incidence was not associated with any outcome except for poorer socio-emotional scores. CONCLUSION: In this population of young children living in a malaria-endemic setting, with active surveillance and treatment, 'presumed' malaria is not associated with change in LAZ, hemoglobin, or iron status, but could be associated with stunting and anemia. Diarrhea was more consistently associated with growth than was malaria or ARI. The findings may be different in contexts where active malaria surveillance and treatment is not provided. TRIAL REGISTRATION: NCT00945698 (July 24, 2009) and NCT01239693 (November 11, 2010).
Subject(s)
Developmental Disabilities/epidemiology , Growth Disorders/epidemiology , Hemoglobins/analysis , Infant Nutrition Disorders/epidemiology , Iron/blood , Malaria/epidemiology , Anemia/epidemiology , Comorbidity , Developmental Disabilities/blood , Diarrhea/epidemiology , Growth Disorders/blood , Humans , Incidence , Infant , Infant Nutrition Disorders/blood , Prevalence , Prospective Studies , Respiratory Tract Infections/epidemiologyABSTRACT
A novel qualitative point-of-care test of activated matrix metalloproteinase-8 (aMMP-8) using noninvasive oral rinse sampling procedures has been developed for the early detection of collagen breakdown indicating periodontal tissue destruction. The main object of this study was to assess the reliability of the test in a low-income setting to identify participants with history of periodontal destruction detected as alveolar bone loss (ABL) in radiographs. This cross-sectional study included 486 women who had recently delivered in rural Malawi. The aMMP-8 test and dental panoramic radiographs were taken within 48 h of delivery. The performance of the test in comparison to radiological examinations was tested by following the standards for reporting of diagnostic accuracy studies protocol (STARD) with respective statistical measures and 95% confidence intervals. From the 486 eligible participants, 461 mothers with complete data, aged from 15 to 46 years (mean 24.8, SD 6.0) were included in the analysis. ABL was identified in 116 of 461 participants. There was 56% agreement between the aMMP-8 test results and detected ABL (yes or no) in radiographs. Calculated sensitivity of the test was 80% (72â»87%), specificity 48% (43â»54%), positive predictive value 34% (31â»37%), negative predictive value 88% (83â»91%), positive likelihood ratio 1.55 (1.35â»1.77), and negative likelihood ratio 0.41(0.28â»0.60). The aMMP-8 test sensitivity and negative predictive value to identify the ABL cases were relatively high, but there was additionally a high rate of test-positive results in participants without ABL, especially in young mothers, leading to low overall agreement between the test results and radiological bone loss. Further longitudinal studies are needed to examine if the test positive subjects are in risk of future bone loss before the detectable signs of periodontitis in radiographs.