Use Of Insecticide-treated Nets Research Articles

Malaria-Associated Factors among Pregnant Women in Guinea.

Introduction Malaria is the leading cause of consultation in Guinea health facilities. During pregnancy, it remains a major health concern causing considerable risks for mother, fetus, and newborn. However, little is known about the epidemiology of malaria among pregnant women in Guinea. We aimed to provide information on malaria-associated factors in parturients. Methods It was a cross-sectional survey in two regional hospitals and two district hospitals. 1000 parturients and their newborns were surveyed. All patients were interviewed, and thick and thin blood smears were examined. To determine the predictive factors of malaria in parturients, the Classification and Regression Tree (CART) was first performed by using peripheral and placental malaria as dependent variables and sociodemographic and antenatal characteristics as independent variables; then, explanatory profile variables or clusters from these trees were included in the logistic regression models. Results We found 157 (15.8%) and 148 (14.8%) cases of peripheral and placental malaria, respectively. The regular use of long-lasting insecticide-treated nets (LLINs) before delivery was 53.8%, and only 35.5% used sulfadoxine-pyrimethamine doses ≥3. Factors significantly associated with malaria were as follows: women from Forécariah and Guéckédou who did not regularly use LLINs and accomplished less than four antenatal care visits (ANC <4) and primigravid and paucigravid women who did not regularly use LLINs. Similarly, the odds of having malaria infection were significantly higher among women who had not regularly used LLINs and among primigravid and paucigravid women who had regularly used LLINs compared to multigravida women who had regularly used LLINs. Conclusion This study showed that pregnant women remain particularly vulnerable to malaria; therefore, strengthening antenatal care visit strategies by emphasizing on promoting the use of LLINs and sulfadoxine-pyrimethamine, sexual education about early pregnancies, and family or community support during first pregnancies might be helpful.

Utilization of key preventive measures for pregnancy complications and malaria among women in Jimma Zone, Ethiopia

BackgroundIn Ethiopia, malaria infections and other complications during pregnancy contribute to the high burden of maternal morbidity and mortality. Preventive measures are available, however little is known about the factors influencing the uptake of maternal health services and interventions by pregnant women in Ethiopia.MethodsWe analyzed data from a community-based cross-sectional survey conducted in 2016 in three rural districts of Jimma Zone, Ethiopia, with 3784 women who had a pregnancy outcome in the year preceding the survey. We used multivariable logistic regression models accounting for clustering to identify the determinants of antenatal care (ANC) attendance and insecticide-treated net (ITN) ownership and use, and the prevalence and predictors of malaria infection among pregnant women.ResultsEighty-four percent of interviewed women reported receiving at least one ANC visit during their last pregnancy, while 47% reported attending four or more ANC visits. Common reasons for not attending ANC included women’s lack of awareness of its importance (48%), distance to health facility (23%) and unavailability of transportation (14%). Important determinants of ANC attendance included higher education level and wealth status, woman’s ability to make healthcare decisions, and pregnancy intendedness. An estimated 48% of women reported owning an ITN during their last pregnancy. Of these, 55% reported to have always slept under it during their last pregnancy. Analysis revealed that the odds of owning and using ITNs were respectively 2.07 (95% CI: 1.62–2.63) and 1.73 (95% CI: 1.32–2.27) times higher among women who attended at least one ANC visit. The self-reported prevalence of malaria infection during pregnancy was low (1.4%) across the three districts. We found that young, uneducated, and unemployed women presented higher odds of malaria infection during their last pregnancy.ConclusionANC and ITN uptake during pregnancy in Jimma Zone fall below the respective targets of 95 and 90% set in the Ethiopian Health Sector Transformation Plan for 2020, suggesting that more intensive programmatic efforts still need to be directed towards improving access to these health services. Reaching ANC non-users and ITN ownership and use as part of ANC services could be emphasized to address these gaps.

Mosquito Exposure and Malaria Morbidity: A Microlevel Analysis of Household Mosquito Populations and Malaria in a Population-Based Longitudinal Cohort in Western Kenya.

Malaria morbidity is highly overdispersed in the population. Fine-scale differences in mosquito exposure may partially explain this heterogeneity in individual malaria outcomes. In 38 households we explored the effect of household-level mosquito exposure and individual insecticide-treated net (ITN) use on relative risk (RR) of confirmed malaria. We conducted monthly active surveillance (n = 254; 2624 person-months) and weekly mosquito collection (2092 household-days of collection), and used molecular techniques to confirm human blood feeding and exposure to infectious mosquitoes. Of 1494 female Anopheles (89.8% Anopheles gambiae sensu lato), 88.3% were fed, 51.9% had a human blood meal, and 9.2% were sporozoite infected. In total, 168 laboratory-confirmed malaria episodes were reported (incidence rate 0.064 episodes per person-month at risk; 95% confidence interval [CI], .055-.074). Malaria risk was directly associated with exposure to sporozoite-infected mosquitoes (RR, 1.24; 95% CI, 1.11-1.38). No direct effect was measured between ITN use and malaria morbidity; however, ITN use did moderate the effect of mosquito exposure on morbidity. Malaria risk increases linearly with vector density and feeding success for persons with low ITN use. In contrast, malaria risk among high ITN users is consistently low and insensitive to variation in mosquito exposure.

Spatial Effects of Permethrin-Impregnated Bed Nets on Child Mortality: 26 Years on, a Spatial Reanalysis of a Cluster Randomized Trial.

.In addition to the direct effect of insecticide-treated nets (ITNs), there has been evidence for spatial indirect effects. Spatial analyses in cluster randomized trials (CRTs) are rare, but a large-scale CRT from 1993 was one of the first to conduct a spatial analysis of ITNs in CRTs. We revisit these data by applying a broader range of contemporary spatial methods to further explore spatial spillover. We conducted three analyses: 1) exploratory spatial analysis, considering spatial patterns and spillover in the data; 2) spatial modeling, estimating the intervention effect considering spatial effects; and 3) analysis of distance-based spillover and interaction with the intervention, characterizing the functional distance over which the spillover effect was present. There were consistent indications of spatial patterns from the exploratory analysis. Bed nets were associated with a 17% reduction in all-cause mortality for children aged 6–59 months, and the intervention estimate remained robust when allowing for the spatial structure of the data. There was strong evidence of a spatial spillover effect: for every additional 100 m that a control household was from an intervention household (and vice versa), the standardized mortality ratio (SMR) increased by 1.7% (SMR 1.017, 95% credible interval 1.006–1.026). Despite evidence of a spatial spillover effect, the conclusions of the trial remain unaffected by spatial model specifications. Use of ITNs was clearly beneficial for individuals, and there was compelling evidence that they provide an indirect benefit to individuals living nearby. This article demonstrates the extra utility that spatial methods can provide when analyzing a CRT.

Prevalence, Morphological Classification, And Factors Associated With Anemia Among Pregnant Women Accessing Antenatal Clinic At Itojo Hospital, South Western Uganda.

PurposeThe study aimed to determine the prevalence, morphological classification, and risk factors of anemia among pregnant mothers attending antenatal clinic at Itojo hospital, Ntungamo district, southwestern Uganda.Patients and methodsAfter obtaining an informed consent, 5mL of blood was collected from the vein of each participant for complete blood count (CBC) and peripheral film report. The CBC was performed using HumaCount 80 hematology analyzer (HUMAN Gesellschaft für Biochemica und Diagnostica mbH Max-Planck-Ring 21 65,205 Wiesbaden Germany). Peripheral blood smears were made and stained using Wright’s Romanowsky stain and examined under ×1000 magnification for morphological classification of anemia. Structured questionnaires were administered to each participant to collect information on patients’ demography and risk factors of anaemia in pregnancy. The data generated were prepared in EXCEL and later transferred to SPSS version 20 for analysis. Univariate logistic regression and multivariate logistic regression were used to evaluate the association of socio-demographic characteristics of the participants with anemia. A 95% confidence level was used and statistical significance was reached at p<0.05.ResultsOne hundred and sixty-three participants (n=163) were recruited for the study with the median age of 25 years and range of (17 to 40 years). The overall prevalence of anemia was 12 (7.4%), the morphological classification was 1 (8.3%) normocytic normochromic anemia, 6 (50%) microcytic hypochromic anemia, and 5 (41.7%) macrocytic anemia. Spouse occupation (p=0.03), household income (p=0.04), use of insecticide-treated mosquito nets (p=0.001), history of urinary tract infection (p=0.002), use of haematinics (p≤0.001), and history of postpartum hemorrhage (p=0.03) were significantly associated with anemia in pregnancy.ConclusionDespite the reported high prevalence of anemia in pregnancy in other areas within the country, anemia prevalence was low in this study. Routine screening for anemia at all antenatal care clinics countrywide is recommended.

Net age, but not integrity, may be associated with decreased protection against Plasmodium falciparum infection in southern Malawi

BackgroundDistribution campaigns for insecticide-treated nets (ITN) have increased the use of ITNs in Malawi, but malaria prevalence remains high even among those using the nets. Previous studies have addressed ITN ownership, insecticide resistance, and frequency of ITN use as possible contributing factors to the high prevalence of malaria infection despite high ITN coverage, but have rarely considered whether the condition of the ITN, or how many people use it, impacts efficacy. This study assessed how ITN integrity, ITN age, and the number of persons sharing a net might mitigate or reduce protective efficacy among self-identified ITN users in Malawi.MethodsFrom 2012 to 2014, six cross-sectional surveys were conducted in both the rainy and dry seasons in southern Malawi. Data were collected on ITN use, integrity (number and size of holes), and age. Blood samples for detecting Plasmodium falciparum infection were obtained from reported ITN users over 6 months of age. Generalized linear mixed models were used to account for clustering at the household and community level. The final model controlled for gender, household eaves, and community-level infection prevalence during the rainy season.ResultsThere were 9646 ITN users with blood samples across six surveys, 15% of whom tested positive for P. falciparum infection. Among children under 5 years old, there was a 50% increased odds of P. falciparum infection among those sleeping under an ITN older than two years, compared to those using an ITN less than 2 years old (OR = 1.50; 95% CI 1.07–2.08). ITN integrity and number of individuals sharing an ITN were not associated with P. falciparum infection.ConclusionsOlder ITNs were associated with higher rates of P. falciparum in young children, which may indicate that insecticide concentrations play a larger role in infection prevention than the physical barrier of an ITN. ITN use was self-reported and the integrity measures lacked the precision of newer methods, suggesting a need for objective measures of ITN use and more precise assessment of ITN integrity.

Drinking water and sanitation conditions are associated with the risk of malaria among children under five years old in sub-Saharan Africa: A logistic regression model analysis of national survey data

Current efforts for the prevention of malaria have resulted in notable reductions in the global malaria burden; however, they are not enough. Good hygiene is universally considered one of the most efficacious and straightforward measures to prevent disease transmission. This work analyzed whether improved drinking water and sanitation (WS) conditions were associated with a decreased risk of malaria infection. Data were acquired through surveys published between 2006 and 2018 from the Demographic and Health Program in sub-Saharan Africa (SSA). Multiple logistic regression was used for each national survey to identify the associations between WS conditions and malaria infection diagnosed by microscopy or a malaria rapid diagnostic test (RDT) among children (0–59 months), with adjustments for age, gender, indoor residual spraying (IRS), insecticide-treated net (ITN) use, house quality, and the mother’s highest educational level. Individual nationally representative survey odds ratios (ORs) were combined to obtain a summary OR using a random-effects meta-analysis. Among the 247,440 included children, 18.8% and 24.2% were positive for malaria infection based on microscopy and RDT results, respectively. Across all surveys, both unprotected water and no facility users were associated with increased malaria risks (unprotected water: aOR 1.17, 95% CI 1.07–1.27, P = 0.001; no facilities: aOR 1.35, 95% CI 1.24–1.47, P < 0.001; respectively), according to microscopy, whereas the odds of malaria infection were 48% and 49% less among piped water and flush-toilet users, respectively (piped water: aOR 0.52, 95% CI 0.45–0.59, P < 0.001; flush toilets: aOR 0.51, 95% CI 0.43–0.61, P < 0.001). The trends of individuals diagnosed by RDT were consistent with those of individuals diagnosed by microscopy. Risk associations were more pronounced among children with a “nonpoor” socioeconomic status who were unprotected water or no facility users. WS conditions are a vital risk factor for malarial infection among children (0–59 months) across SSA. Improved WS conditions should be considered a potential intervention for the prevention of malaria in the long term.

Effects of insecticide-treated net access and use on infant mortality in Malawi: A pooled analysis of demographic health surveys

Malaria continues to be among the top causes of death in children and insecticide-treated nets (ITNs) are considered among the most effective malaria control methods. However, information on the association between universal ITN coverage and infant mortality is limited. A Cox proportional hazard model was applied to Malawi Demographic and Health Surveys to determine the association between ITN access and use and infant mortality between 2004 and 2015–2016. The overall infant mortality rate for the entire period was 47.9/1000 live births. Infants from the ITN-user households exhibited a lower risk of mortality [adjusted Hazard Ratio (aHR) = 0.61, 95% Confidence Interval (CI) = 0.44–0.85] than those from the ITN-nonuser households. Similarly, the infants from the high-access households exhibited a lower risk of death (aHR = 0.63, 95% CI = 0.46–0.86) than those from the no-access households. Infants from the ITN-user and high-access households exhibited a significantly lower risk of death (aHR = 0.57, 95% CI = 0.40–0.82) than those from the ITN-nonuser and no-access households. The relationship between ITN access and use and infant mortality was significant among female infants with a second or higher birth order and interval of ≥2 years. The findings of the present population-based study emphasized the importance of ITN access and use in providing optimal protection against malaria to infants in Malawi. Malaria control programs should ensure high ITN access and use in Malawi to reduce infant mortality.

Misperceptions of patients and health workers regarding malaria elimination in the Brazilian Amazon: a qualitative study

BackgroundBrazil has considerably reduced the number of cases of malaria in recent years and aims to eradicate the disease completely, however, vivax malaria continues to be a major challenge for the health system. In this context, the key to building a successful elimination programme may lie in the knowledge and the perceptions of the health agents, the patients affected by the disease and the personnel responsible for malaria diagnosis, treatment and control at the local level.MethodsA qualitative study was undertaken in Manaus, capital of the state of Amazonas, Western Brazilian Amazon, using a sample of 33 patients who were being treated for malaria and 22 health agents who were working in malaria diagnosis, treatment and control at the local level. A semi-structured interview with a further thematic analysis was performed.ResultsThere are still many myths regarding malaria transmission and treatment that may hinder the sensitization of the population of this region in relation to the use of current control tools and elimination strategies, such as mass drug administration (MDA). Most health professionals reported that the abandonment of treatment for malaria by the patient is related to poor social conditions, the high incidence of alcoholism and the low level of schooling of the affected population. One negative perception, observed in both groups with regard to the use of insecticide-treated nets, is that they may cause skin irritations and allergies. Most patients and health professionals have described malaria as an impossible disease to eliminate because it is intrinsically associated with forest landscapes, and according to them, elimination would only be possible if there were a vaccine against malaria.ConclusionIn the Amazon, cultural perceptions about the etiology of this disease can influence the behaviour and practices that social groups adopt in relation to the different forms of living in a malaria-endemic context. Negative perceptions about malaria elimination can act as a barrier when trying to reach proper coverage for control strategies such as mosquito nets and MDA.

Quantifying Seasonal Variation in Insecticide-Treated Net Use among Those with Access.

.Seasonal variation in the proportion of the population using an insecticide-treated net (ITN) is well documented and is widely believed to be dependent on mosquito abundance and heat, driven by rainfall and temperature. However, seasonal variation in ITN use has not been quantified controlling for ITN access. Demographic and Health Survey and Malaria Indicator Survey datasets, their georeferenced data, and public rainfall and climate layers were pooled for 21 countries. Nine rainfall typologies were developed from rainfall patterns in Köppen climate zones. For each typology, the odds of ITN use among individuals with access to an ITN within their households (“ITN use given access”) were estimated for each month of the year, controlling for region, wealth quintile, residence, year, temperature, and malaria parasitemia level. Seasonality of ITN use given access was observed over all nine rainfall typologies and was most pronounced in arid climates and less pronounced where rainfall was relatively constant throughout the year. Peak ITN use occurred 1–3 months after peak rainfall and corresponded with peak malaria incidence and average malaria transmission season. The observed lags between peak rainfall and peak ITN use given access suggest that net use is triggered by mosquito density. In equatorial areas, ITN use is likely to be high year-round, given the presence of mosquitoes and an associated year-round perceived malaria risk. These results can be used to inform behavior change interventions to improve ITN use in specific times of the year and to inform geospatial models of the impact of ITNs on transmission.

Knowledge, attitudes, and practices regarding malaria control among the slash and burn cultivators in Rangamati Hill tracts of Bangladesh

BackgroundSlash and burn cultivators are a significant risk group for malaria in South-East Asia. As envisaged in the National Strategic Plan for Malaria Elimination, Bangladesh aims to achieve zero indigenous malaria transmission by 2030. For the national plan to move from malaria control to malaria elimination, targeting the population of slash and burn cultivators is of overriding importance.MethodsThe study used an explorative mixed method design to investigate the knowledge, attitudes, and practices (KAP) regarding malaria prevention and treatment in an endemic area of Bangladesh. Adult slash and burn cultivators in two sub-districts of the Rangamati District were selected and interviewed. Four focus group discussions were conducted, and this was followed by a cross-sectional quantitative survey with 200 participants.ResultsThe respondents’ general knowledge about malaria transmission and modes of prevention and treatment was good. However, there were some gaps regarding knowledge about specific aspects of malaria transmission and in particular about the increased risk associated with their occupation. Despite a much-reduced incidence of malaria in the study area, the respondents perceived the disease as life-threatening and knew that it needs rapid attention from a health worker. Moreover, the specific services offered by the local community health workers for malaria diagnosis and treatment were highly appreciated. Finally, the use of insecticide-treated mosquito nets (ITN) was considered as important and this intervention was uniformly stated as the main malaria prevention method.ConclusionsThe findings from this study on promising KAP characteristics in the slash and burn cultivator population are reassuring that the goal of malaria elimination by the year 2030 can be achieved in Bangladesh.

A subnational profiling analysis reveals regional differences as the main predictor of ITN ownership and use in Nigeria

BackgroundTo reduce the malaria burden in Nigeria, the country is scaling up prevention and treatment interventions, especially household ownership and use of insecticide-treated nets (ITNs). Nevertheless, large gaps remain to achieve the goals of the National Malaria Strategic Plan 2014–2020 of universal access to ITNs and their increased use. To inform the targeting of intervention strategies and to maximize impact, the authors conducted a sub-national profiling of household ITN ownership and use in the general population to identify key predictors of ITN ownership and use, and the sub-groups that are at higher risk of low ITN coverage and use.MethodsThe authors conducted a secondary analysis of data from the 2015 Nigeria Malaria Indicator Survey. Using the Chi square automatic interaction detector (CHAID) and multiple logistic regression analysis, the authors examined the key predictors of ITN ownership and use in the general population throughout Nigeria.ResultsThe CHAID models identified region of the country as the best predictor of household ownership of at least one ITN and its use in the general population, with higher ownership and use observed in the northern regions. The odds of a household owning an ITN were five times greater in the North West region compared with the North Central region (odds ratio [OR] = 5.47, 95% confidence interval [CI] 4.46–6.72, p < 0.001). The odds of ITN use were two times greater for those living in the North West region compared with the North Central region (OR = 2.04, 95% CI 1.73–2.41, p < 0.001). Other significant predictors were household size, head of household education level, household wealth quintile, and place of residence. The CHAID gain index results identified households in the South West, North Central and South Central regions with low ITN ownership, and the general population in the South South, South East and North Central regions with low ITN use.ConclusionsThis study reveals regional differences in ITN ownership and use in Nigeria. Therefore, the findings from this analysis provide evidence that could inform the NMEP to better target future campaign and routine distribution of ITNs, to achieve universal access and increased use by 2020 in Nigeria.

The President's Malaria Initiative contributed to reducing malaria burden in sub-Saharan Africa between 2004 and 2014: Evidence from generalized estimating equation analysis.

The President’s Malaria Initiative (PMI) launched in 2005 as a key player in malaria prevention and treatment in sub-Saharan Africa (SSA). Several country-specific evaluations have demonstrated great progress in reducing under-five mortality associated with scaling up malaria interventions in PMI priority countries. Documentation of PMI’s specific contributions was limited, until the publication of Jakubowski, et al., which used difference-in-difference analysis to show a higher reduction of under-five mortality in PMI-supported countries than in others. To generate more evidence, this study used rigorous statistical analyses to assess the reduction in mortality attributable to PMI support. The study used generalized estimating equations and a series of matching procedures to evaluate the impact of PMI on under-five mortality and on population coverage of insecticide-treated nets (ITNs), indoor residual spraying (IRS), and artemisinin-based combination therapy (ACT) in SSA. The analyses used country-level secondary data and controlled for several country-level characteristics assumed to influence outcome measures of interest, PMI program participation, or both. The Mahalanobis distance metric, with 1:1 nearest neighbor matching adjusting for bias in population size in the particular country, showed a reduction in under-five mortality by approximately 12 per 1,000 live births (95% Confidence Interval [CI]: 20.6–3.1; p = 0.012). There were statistically significant increases in the population coverage of ITNs, IRS, and ACTs in PMI countries over the implementation period. ITN use in the population was 0.23% higher (95% CI average treatment effect on the treated: 0.17–0.30; p<0.001) in PMI-recipient countries than in non-PMI countries. The findings show that PMI contributed significantly to increasing the coverage of malaria control interventions and reducing under-five mortality in SSA.

Optimal control and cost-effectiveness analysis of a Zika virus infection model with comprehensive interventions

Zika virus is a mosquito-borne virus and can spread to humans via bites by infected vectors or through sexual contact with infectious humans. Various protective and control measures such as the use of insecticide-treated nets, condoms, indoor residual spraying and medical treatment of infected humans may mitigate the infection. In this paper, we formulate and analyze a mathematical model that incorporates these comprehensive interventions to study the impact of mosquito-to-human and sexual transmission on the disease dynamics. We obtain the basic reproduction number, study when the disease dies out, and investigate the sensitivity of the basic reproduction number on each control. Numerical results suggest that vector transmission contributes more to the basic reproduction number than sexual transmission. We also formulate the optimal control problem and obtain the necessary conditions that minimize the population of infected individuals and the associated costs. Using the cost effectiveness analysis, we show that a combination of condom use and medical treatment of infected people provides the most cost-effective strategy to control the disease.

Plasmodium falciparum Infection among Febrile Patients Attending a Tertiary Healthcare Facility in Central Nigeria: Prevalence, Hematologic and Sociodemographic Factors

The overall prevalence of P. falciparum infection was 227/400 (56.8%). The prevalence with respect to patient's categories was children (68.1%), pregnant women (67.0%), male adult (47.1%) and female adult (42.0%). The infection was high among genotype AA (83.0%), blood group A (90.8%), females (57.7%), rhesus factor positive (57.7%), age < 15 years (72.4%), those who use insecticide-treated mosquito nets (55.8%) and those with PCV range 20-25 (86.7%). Genotype, blood group, and age were statistically associated with P. falciparum (p < 0.05). In this study, categories of patients, gender, rhesus factor, use of insecticide-treated mosquito nets (ITNs) and packed cell volume (PCV) ranges were not associated statistically with the infection (p > 0.05).

PO 8575 EVOLUTION OF MALARIA MORBIDITY IN TWO VILLAGES IN KOROGWE, TANZANIA

BackgroundThe malaria burden has decreased significantly in recent years in sub-Saharan Africa due to targeted interventions aimed at parasites and vectors. However, studies have shown that a limited number of infective bites makes individuals in malaria-endemic regions more susceptible to subsequent malaria infection as they grow older due to waning or lost immunity. This study investigated the evolution of malaria morbidity for 14 years in Korogwe, Tanzania since 2003.MethodsA longitudinal study was carried out in Korogwe over 14 years, from January 2003 to December 2017 whereby community health workers (CHWs) passively monitored malaria episodes at a village health post. They evaluated febrile episodes and collected blood smears from all residents of the community who presented with fever. The blood smears were processed and read at the Korogwe field station by two independent microscopists. Artemisinin combination therapy (ACT) and malaria rapid diagnostic tests were introduced in the community in 2007. Uncomplicated malaria cases were treated with sulphadoxine-pyrimethamine (SP) from 2003 to 2006, then with artemether-lumefantrine (ALu) from 2007.ResultsA total of 20,841 attendances were documented by CHWs between 2003 and 2017. Malaria parasitaemia was documented in 5043 consultations [24.1% (95% confidence interval (CI): 23.6% to 24.8%)]. Interestingly, malaria episodes declined markedly from 38.12% to 10.42% between 2003 and 2017. The highest reduction was documented in 2010 (at 3.1%) but thereafter, there was an increase in malaria in 2015 to 32.2% which decreased to 10.42% in 2017. Use of long-lasting insecticide-treated nets (LLINs) was associated with reduction of malaria episodes by 34% (95% CI: 26% to 42%).ConclusionPrompt diagnosis at village level, use of ACT and LLINs has contributed to the reduced number of malaria episodes in Korogwe. However, the malaria resurgences raised concerns about malaria elimination in these communities.

Exploring the heterogeneity of human exposure to malaria vectors in an urban setting, Bouak\xe9, C\xf4te d\u2019Ivoire, using an immuno-epidemiological biomarker

BackgroundIn some African cities, urban malaria is a threat to the health and welfare of city dwellers. To improve the control of the disease, it is critical to identify neighbourhoods where the risk of malaria transmission is the highest. This study aims to evaluate the heterogeneity of malaria transmission risk in one city (Bouaké) in a West African country (Côte d’Ivoire) that presents several levels of urbanization.MethodsTwo cross-sectional studies were conducted in three neighbourhoods (Dar-es-Salam, Kennedy and N’gattakro) in Bouaké during both the rainy and dry seasons. Data on insecticide-treated net (ITN) use and blood samples were collected from children aged between 6 months and 15 years to determine the parasite density and the prevalence of Plasmodium falciparum and the level of IgG against the Anopheles gSG6-P1 salivary peptide, used as the biomarker of Anopheles bite exposure.ResultsThe specific IgG levels to the gSG6-P1 salivary peptide in the rainy season were significantly higher compared to the dry season in all neighbourhoods studied (all p < 0.001). Interestingly, these specific IgG levels did not differ between neighbourhoods during the rainy season, whereas significant differences in IgG level were observed in the dry season (p = 0.034). ITN use could be a major factor of variation in the specific IgG level. Nevertheless, no difference in specific IgG levels to the gSG6-P1 salivary peptide was observed between children who declared “always” versus “never” sleeping under an ITN in each neighbourhood. In addition, the prevalence of P. falciparum in the whole population and immune responders was significantly different between neighbourhoods in each season (p < 0.0001).ConclusionThis study highlights the high risk of malaria exposure in African urban settings and the high heterogeneity of child exposure to the Anopheles vector between neighbourhoods in the same city. The Anopheles gSG6-P1 salivary peptide could be a suitable biomarker to accurately and quantitatively assess the risk of malaria transmission in urban areas.

Effects of a health educational intervention on malaria knowledge, motivation, and behavioural skills: a randomized controlled trial

BackgroundThe levels of insecticide-treated net use among pregnant women and uptake of intermittent preventive treatment in pregnancy, have been sub-optimal in Nigeria. Previous studies have reported positive correlations between knowledge, attitude and practice of malaria preventive measures. It has also been reported that information and motivation, act through a mediator (behavioural skills), to cause a health behaviour change. The aim of this study was as such to develop, implement, and assess the effects of a health educational intervention based on the information–motivation–behavioural skills (IMB) model on the levels of knowledge, motivation, and behavioural skills for ITN use and IPTp uptake among pregnant women in a hospital in north-eastern Nigeria.MethodsThis was a randomized controlled parallel-group trial in which 372 antenatal care attendees were randomly assigned to either an intervention or control group after collecting baseline data using a structured questionnaire. The intervention group received a 4-h health education on malaria, guided by a module developed based on the IMB theory, while the control group received health education on breastfeeding for a similar duration and by the same facilitator. Follow-up data were subsequently collected at 2 months and at 4 months post-intervention using the same questionnaire. The generalized linear mixed models analysis was used to determine the between-group and within-group effects of the intervention. The intention-to-treat analysis was used after missing data had been replaced. This was followed by a sensitivity analysis, where the analyses were repeated without replacing the missing values.ResultsThe intervention was significant in achieving a 12.75% (p < 0.001), 8.55% (p < 0.001), and 6.350% (p < 0.001) higher total knowledge, motivation, and behavioural skills scores respectively, for the intervention group over the control group. The sensitivity analysis revealed no great differences in the effect sizes, even when missing data were not replaced.ConclusionThe intervention module was effective in improving knowledge, motivation and behavioural skills. It is as such recommended to be adopted and incorporated into the routine antenatal health education schedules. It is also recommended that booster doses of the module be given say 2 months after the first dose to sustain levels of motivation and behavioural skills.Trial registration Pan African Clinical Trial Registry, PACTR201610001823405. Registered 26 October 2016, http://www.pactr.org

Reproductive-Age Women's Knowledge and Care Seeking for Malaria Prevention and Control in Ghana: Analysis of the 2016 Malaria Indicator Survey.

Introduction Malaria is a major cause of morbidity and mortality worldwide, requiring individual and environmental level controls to prevent its adverse morbidity effects. This study examined reproductive-aged women's knowledge and care-seeking practices for malaria prevention and control in Ghana. Methods The 2016 Ghana Malaria Indicator Survey data for reproductive-age women was analysed (n=5,150). Multilevel mixed-effects logistic regression model was used to determine factors associated with reproductive-aged women's knowledge and care-seeking practices for malaria. Results 62.3%, 81.3%, and 64.6% knowledge levels on causes, signs/symptoms, and prevention of malaria were found, respectively, among respondents. Age, wealth and educational status, religion, region, and place of residence (rural) were found to significantly influence respondents' knowledge of causes, signs/symptoms, and care-seeking practices for malaria. A 15% differential among Insecticide Treated Nets (ITNs) awareness and use was found. Increasing age (≥35 years) was associated with increasing knowledge of malaria. Regional variations were observed to significantly influence knowledge of malaria treatment. Conclusion Though ownership of ITNs and knowledge of malaria prevention were high, it did not necessarily translate into use of ITNs. Thus, there is a need to intensify education on the importance and the role of ITNs use in the prevention of malaria.

Implications of insecticide resistance for malaria vector control with long-lasting insecticidal nets: evidence from health facility data from Benin

BackgroundInsecticide-based interventions have averted more than 500 million malaria cases since 2000, but insecticide resistance in mosquitoes could bring about a rebound in disease and mortality. This study investigated whether insecticide resistance was associated with increased incidence of clinical malaria.MethodsIn an area of southern Benin with insecticide resistance and high use of insecticide-treated nets (ITNs), malaria morbidity and insecticide resistance were measured simultaneously in 30 clusters (villages or collections of villages) multiple times over the course of 2 years. Insecticide resistance frequencies were measured using the standard World Health Organization bioassay test. Malaria morbidity was measured by cases recorded at health facilities both in the whole population using routinely collected data and in a passively followed cohort of children under 5 years old.ResultsThere was no evidence that incidence of malaria from routinely collected data was higher in clusters with resistance frequencies above the median, either in children aged under 5 (RR = 1.27 (95% CI 0.81–2.00) p = 0.276) or in individuals aged 5 or over (RR = 1.74 (95% CI 0.91–3.34) p = 0.093). There was also no evidence that incidence was higher in clusters with resistance frequencies above the median in the passively followed cohort (RR = 1.11 (0.52–2.35) p = 0.777).ConclusionsThis study found no association between frequency of resistance and incidence of clinical malaria in an area where ITNs are the principal form of vector control. This may be because, as other studies have shown, ITNs continue to offer some protection from malaria even in the presence of insecticide resistance. Irrespective of resistance, nets provide only partial protection so the development of improved or supplementary vector control tools is required to reduce Africa’s unacceptably high malaria burden.