Use Of Insecticide-treated Nets Research Articles

Delivering insecticide-treated nets (ITNs) through a digitized single-phase door-to-door strategy: lessons from Ondo state, Nigeria

BackgroundThe use of insecticide-treated nets (ITNs) is a strategy recommended by the World Health Organization (WHO) for malaria prevention. In Nigeria, ITNs have been periodically distributed since 2007 through campaigns. Campaign activities and assets are typically tracked using either a paper-based or digital system. In 2017, a digital approach was introduced in Ondo state for tracking attendance at training sessions as part of the ITN campaign. Following the success of the 2017 introduction, subsequent campaigns planned to digitise other aspects of the campaign to improve accountability and efficiency of the ITN distribution. The COVID-19 pandemic posed additional challenges for the ITN distribution planned for 2021 and adaptations were made to the programme strategy to ensure the campaign could go ahead safely. This article presents lessons and experiences from the 2021 ITN distribution campaign in Ondo state, Nigeria.MethodsThe campaign used RedRose, a customised mobile application, to monitor the planning and delivery of the campaign, collect household information including training personnel and tracking the transfer of ITNs between distribution hubs and households. ITNs were delivered through a single-phase door-to-door distribution strategy.ResultsThe campaign distributed 2,965,125 ITNs covering 1,057,577 households across Ondo state. The digital application was beneficial for monitoring the quality of implementation and tracking assets and staff to ensure safety.. The single-phase door-to-door approach was more convenient for households compared to fixed-point distribution but increased the workload for mobilization and distribution teams.ConclusionsSingle phase door-to-door strategy using digital tools was an effective method to increase coverage of ITNs while closely tracking the progress of distribution campaigns. High-quality population data are needed to further improve the planning and implementation of ITN campaigns and other health interventions.

The influence of malaria control interventions and climate variability on changes in the geographical distribution of parasite prevalence in Kenya between 2015 and 2020

BackgroundThe burden of malaria in Kenya was showing a declining trend, but appears to have reached a plateau in recent years. This study estimated changes in the geographical distribution of malaria parasite risk in the country between the years 2015 and 2020, and quantified the contribution of malaria control interventions and climatic/ environmental factors to these changes.MethodsBayesian geostatistical models were used to analyse the Kenyan 2015 and 2020 Malaria Indicator Survey (MIS) data. Bivariate models were fitted to identify the most important control intervention indicators and climatic/environmental predictors of parasitaemia risk by age groups (6–59 months and 5–14 years). Parasitaemia risk and the number of infected children were predicted over a 1 × 1 km2 grid. The probability of the decline in parasitaemia risk in 2020 compared to 2015 was also evaluated over the gridded surface and factors associated with changes in parasitaemia risk between the two surveys were evaluated.ResultsThere was a significant decline in the coverage of most malaria indicators related to Insecticide Treated Nets (ITN) and Artemisinin Combination Therapies (ACT) interventions. Overall, there was a 31% and 26% reduction in malaria prevalence among children aged < 5 and 5–14 years, respectively. Among younger children, the highest reduction (50%) and increase (41%) were in the low-risk and semi-arid epi zones, respectively; while among older children there was increased risk in both the low-risk (83%) and semi-arid (100%) epi zones. Increase in nightlights and the proportion of individuals using ITNs in 2020 were associated with reduced parasitaemia risk.ConclusionIncreased nightlights and ITN use could have led to the reduction in parasitaemia risk. However, the reduction is heterogeneous and there was increased risk in northern Kenya. Taken together, these results suggest that constant surveillance and re-evaluation of parasite and vector control measures in areas with increased transmission is necessary. The methods used in this analysis can be employed in other settings.

Activity-based contracting for optimization of the mass distribution of insecticide-treated nets in the Democratic Republic of Congo: pilot implementation in Kwilu province

BackgroundPromoting the use of insecticide-treated mosquito nets (ITNs) is one of the main strategies for reducing malaria-related morbidity. An innovative activity-based contracting (ABC) approach has been implemented in Kwilu Province, Democratic Republic of Congo to optimize ITN mass distribution campaigns, with payments based on contractually defined programmatic outcomes for key campaign activities following independent verification of results.MethodsThis internal evaluation was carried out using a mixed methods approach combining qualitative and quantitative document and content analysis from a series of three workshops: validation workshops for campaign results at provincial level for the 2021 and 2022 campaigns; internal evaluation workshop for the Kwilu campaign as part of the ABC approach organized by “Santé pour tous en milieu rural” (SANRU) with its sub-contractors; and national campaign evaluation workshop organized by the National Malaria Control Program.ResultsThe pilot campaign with the ABC approach in Kwilu has demonstrated better results than campaigns conducted using the standard, non-ABC, approach: better household coverage (99.9% vs. 97.3%) and improved compliance with ITN allocation to households based on the household size (98. 9% vs. 84.7%); lower loss of ITNs (0.3% vs. 0.5%) with immediate penalties for lost ITNs in the province under the ABC approach; shorter campaign lead times (14 vs. 28 weeks from the start of training to the launch of distribution). This last point is crucial, as it is likely to generate efficiencies and contribute to ensuring timely ITN replacement campaigns.ConclusionThe challenges encountered and the lessons learned in the implementation of the pilot ABC approach in Kwilu could guide future distribution campaigns in the DRC and other African countries that would like to engage in distribution campaigns based on performance-based incentive contracts.

Malaria Prevention and Control in Nigeria: Evaluating the Effectiveness of Current Strategies

Malaria has been a significant public health challenge in Nigeria, contributing to high morbidity and mortality rates, particularly among children under five and pregnant women. Despite all efforts made to control and prevent malaria, Nigeria continued to bear a disproportionate share of the global malaria burden. This review critically evaluated the effectiveness of current malaria prevention and control strategies in Nigeria, including the use of insecticide-treated nets (ITNs), indoor residual spraying (IRS), chemoprevention, and public health education campaigns. The methodology involved a comprehensive analysis of peer-reviewed studies, government reports, and data from international health organizations to assess these strategies. The review identified gaps in the implementation of these strategies and explored innovative approaches that could enhance their impact. It also discussed the role of environmental management, community engagement, and the integration of technology in malaria control efforts. The findings suggested that while existing strategies have made significant progress in reducing malaria transmission, challenges such as resistance to insecticides, inconsistent use of preventive measures, and limited healthcare infrastructure hindered their overall effectiveness. The review concluded by proposing recommendations for strengthening malaria prevention and control efforts in Nigeria, with a focus on sustainability, scalability, and community involvement. Keywords: Malaria Control, Insecticide-Treated Nets (ITNs), Indoor Residual Spraying (IRS), Chemoprevention, Environmental Management.

Assessment of knowledge, attitude, and practices toward malaria in the Lunglei district, Mizoram, North-East India

BackgroundThe western districts of Mizoram (Lunglei, Mamit, and Lawngtlai) are malaria hotspots. Understanding the knowledge, attitude, and practices of the tribal communities in Mizoram’s western districts will aid the development of specific interventions.MethodsAn explanatory sequential mixed-method study was conducted from April to November 2023 in the Lunglei district. In a community-based cross-sectional survey of 353 participants, the knowledge, attitude, practices, and care-seeking behaviour toward malaria were assessed using a semi-structured questionnaire. Data was analysed using SPSS version 29 software; univariate variables were presented in percentage, and bivariate and multivariate variables were analysed using the chi-square test and logistic regression, respectively. This was followed by in-depth telephonic interviews of twelve participants, and the data was analysed using NVivo.ResultsOut of the 353 respondents, 77.9%, 82.7%, 55.5%, and 63.2% of the participants had good knowledge, attitude, practices, and care-seeking behaviour, respectively. The in-depth qualitative interviews highlighted the villagers’ good knowledge of the various aspects of malaria transmission, treatment, and prevention practices (indoor residual spraying and use of insecticide-treated nets).ConclusionHigh disease endemicity, awareness programmes and vector control interventions might be contributing to the overall good knowledge, attitude, and practices toward malaria among the villagers. In addition to vector control measures, active parasite surveillance is key to malaria control in this region.

Home-based care practices on prevention of malaria in children under 5 years: A narrative review.

Malaria is a major threat to lives in developing countries, especially in Africa. A lot of measures have been tried to curb the increased mortality and morbidity associated with malaria. A lot of resources have been channeled to control the devastating effects of malaria in these parts of the world. The aim of this paper is to discuss home-based care practices on prevention of malaria in children under 5 years. By cutting back on bushes and upholding good hygiene and sanitation, malaria in young children can be prevented in homes. This lessens disease and transmission while also assisting in death prevention and disease reduction. In Africa, Uganda is the third most affected country by malaria, which is a major cause of high morbidity and mortality in young children and pregnant women. This has forced the Government of Uganda and implementing partners, including the Global Fund and the Roll Back Malaria initiative, to redouble efforts to increase the use of insecticide-treated mosquito nets. Effective use of insecticide-treated bed nets is necessary to eliminate the above serious sequelae in children under 5 years old. Households and especially caregivers apply the use of impregnated mosquito nets and cleaning of surrounding bushes. According to research results, the use of indoor residual spray nets and insecticide-impregnated nets has significantly contributed to the prevention of malaria in children.

Malaria prevalence and transmission in the Zakpota sub-district of central Benin: baseline characteristics for a community randomised trial of a new insecticide for indoor residual spraying

BackgroundMalaria transmission is known to be perennial and heterogeneous in Benin. Studies assessing local malaria prevalence, transmission levels and vector characteristics are critical for designing, monitoring and evaluating new vector control interventions in community trials. We conducted a study in the Zakpota sub-district of central Benin to collect baseline data on household characteristics, malaria prevalence, vector characteristics and transmission dynamics in preparation for a randomised controlled trial to evaluate the community impact of VECTRON™ T500, a new broflanilide indoor residual spraying (IRS) product.MethodsA total of 480 children under 5 years of age from the 15 villages of the sub-district were tested for malaria by rapid diagnostic tests (RDTs). Mosquitoes were collected by human landing catches (HLCs), pyrethrum spray catches (PSCs) and Centers for Disease Control and Prevention miniature light traps (CDC-LTs) in selected houses in each village to assess vector density, composition, vector infectivity and prevalence of insecticide resistance markers. Bioassays were performed to detect vector susceptibility to pyrethroids, broflanilide (6 µg/bottle) and clothianidin (90 µg/bottle).ResultsA total of 9080 households were enumerated in the 15 study villages. Insecticide-treated net (ITN) usage was > 90%, with 1–2 ITNs owned per household. Houses were constructed mainly with cement (44%) and mud (38%) substrates or a mixture of cement and mud (18%), and 60% of them had open eaves. The overall prevalence of P. falciparum infection was 19% among surveyed children: 20% among females and 18% among males. The haemoglobin rate showed an anaemia (< 11 g/dl) prevalence of 66%. Anopheles coluzzii and An. gambiae sensu stricto (s.s.) were the two vector species present at an overall proportion of 46% versus 54%, respectively. The human biting rate was 2.3 bites per person per night (b/p/n) and biting occurred mostly indoors compared with outdoors (IRR = 0.776; P = 0.001). The overall proportion of outdoor biting was 44% and exceeded indoor biting in three villages. The sporozoite rate was 2% with a combined yearly entomological inoculation rate (EIR) of 16.1 infected bites per person per year (ib/p/y). There was great variability in malaria transmission risk across the villages, with EIR ranging from 0 to 29.3 ib/p/y. The vector population showed a high intensity of resistance to pyrethroids across the study villages but was largely susceptible to broflanilide and clothianidin.ConclusionsThis study found high levels of malaria prevalence, vector density and transmission in the Zakpota sub-district despite the wide use of insecticide-treated nets. The vector population was mostly indoor resting and showed a high intensity of pyrethroid resistance but was generally fully susceptible to broflanilide. These findings demonstrated the suitability of the study area for the assessment of VECTRON™ T500 in a community randomised trial.Graphical

Efficacy of Interceptor G2, Royal Guard and PermaNet 3.0 against pyrethroid-resistant Anopheles gambiae s.l. from Za-Kpota, southern Benin: an experimental hut trial

BackgroundThe widespread use of insecticide-treated nets (ITNs) has significantly contributed to the reduction in malaria cases and deaths observed across Africa. Unfortunately, this control strategy is threatened by the rapid spread of pyrethroid resistance in malaria vectors. Dual-active-ingredient insecticidal nets are now available to mitigate the impact of pyrethroid resistance. To facilitate evidence-based decisions regarding product selection in specific use settings, data are needed on the efficacy of these different nets against local mosquito populations.MethodsTwo experimental hut trials were performed in Za-Kpota, southern Benin in 2021 to evaluate the performance of Interceptor G2 (BASF), Royal Guard (Disease Control Technologies) and PermaNet 3.0 (Vestergaard Frandsen), all dual-active-ingredient bednets, in comparison to untreated or standard pyrethroid-treated bednets, against free-flying wild Anopheles gambiae mosquitoes. The performance of some of these next-generation nets was compared to the same type of nets that have been in use for up to 2 years. Mosquitoes collected in the huts were followed up after exposure to assess the sublethal effects of treatments on certain life-history traits.ResultsThe predominant species in the study site was Anopheles gambiae sensu stricto (An. gambiae s.s.). Both Anopheles coluzzii and An. gambiae s.s. were resistant to pyrethroids (deltamethrin susceptibility was restored by piperonyl butoxide pre-exposure). In the experimental hut trials, the highest blood-feeding inhibition (5.56%) was recorded for the Royal Guard net, relative to the standard PermaNet 2.0 net (44.44% inhibition). The highest 72-h mortality rate (90.11%) was recorded for the Interceptor G2 net compared to the PermaNet 2.0 net (56.04%). After exposure, the risk of death of An. gambiae sensu lato (An. gambiae s.l.) was 6.5-fold higher with the Interceptor G2 net and 4.4-fold higher with the PermaNet 3.0 net compared to the respective untreated net. Lower mosquito mortality was recorded with an aged Interceptor G2 net compared to a new Interceptor G2 net. Oviposition rates were lower in mosquitoes collected from huts containing ITNs compared to those of untreated controls. None of the mosquitoes collected from huts equipped with Royal Guard nets laid any eggs.ConclusionsThe Royal Guard and Interceptor G2 nets showed a potential to significantly improve the control of malaria-transmitting vectors. However, the PermaNet 3.0 net remains effective in pyrethroid-resistant areas.Graphical

Investigation on Malaria Parasitaemia, Knowledge and Attitudes towards Mosquito Control among Residents of Wukari Metropolis

This study was conducted to investigate malaria parasitaemia, knowledge and attitudes towards mosquito control. 162 subjects were selected at random from different locations in Wukari Metropolis and were examined for malaria parasitaemia. Blood samples from each of the subjects were collected by finger pricking for the determination of malaria parasite using the Rapid Diagnostic Test method. Out of 162 samples examined, the prevalence of malaria parasitaemia was 91(56.17%). Female subjects had the highest prevalence of malaria parasitaemia of (72.0%), while the male had (35.0%) and the difference was statistically significant (p&lt;0.05) between the rate of infection and gender. Age group ≥20 years recorded the highest infection rate of (62.12%), age group 14-16 years had the lowest infection rate of (48.94%), and there was no significant difference p&gt;0.05 between malaria prevalence and age groups. The hospital location had the highest prevalence of malaria parasitaemia at (64.44%) and (31.89%) within malaria, while the Fuwukari location had the least prevalence of malaria parasitaemia of (47.22%) and (18.68%) within malaria. The test on knowledge and awareness of malaria indicates that (31.48%) of the subjects have erroneous perception about the cause and means through which malaria is transmitted. It can be concluded that despite the high infectivity rate of malaria in the study area there is much knowledge and awareness of malaria in the study. There is a need for a comprehensive strategy for preventing malaria transmission such as effective use of insecticide-treated nets, public awareness campaigns, proper environmental sanitation and use of drugs.

Comparison of the Trapping Efficacy of Locally Modified Gravid Aedes Trap and Autocidal Gravid Ovitrap for the Monitoring and Surveillance of Aedes aegypti Mosquitoes in Tanzania.

The study assessed the trapping efficacy of locally modified (1) Gravid Aedes Trap (GAT) lined with insecticide-treated net (ITN) as a killing agent and (2) Autocidal Gravid Ovitrap (AGO) with sticky board in the semi-field system (SFS) and field setting. Fully balanced Latin square experiments were conducted to compare GAT lined with ITN vs. AGO, both with either yeast or grass infusion. Biogent-Sentinel (BGS) with BG-Lure and no CO2 was used as a standard trap for Aedes mosquitoes. In the SFS, GAT outperformed AGO in collecting both nulliparous (65% vs. 49%, OR = 2.22, [95% CI: 1.89-2.60], p < 0.001) and gravid mosquitoes (73% vs. 64%, OR = 1.67, [95% CI: 1.41-1.97], p < 0.001). Similar differences were observed in the field. Yeast and grass infusion did not significantly differ in trapping gravid mosquitoes (OR = 0.91, [95% CI: 0.77-1.07], p = 0.250). The use of ITN improved mosquito recapture from 11% to 70% in the SFS. The same trend was observed in the field. Yeast was chosen for further evaluation in the optimized GAT due to its convenience and bifenthrin net for its resistance management properties. Mosquito density was collected when using 4× GATs relative to BGS-captured gravid mosquitoes 64 vs. 58 (IRR = 0.82, [95% CI: 0.35-1.95], p = 0.658) and showed no density dependence. Deployment of multiple yeast-baited GAT lined with bifenthrin net is cost-effective (single GAT < $8) compared to other traps such as BGS ($160).

Prevalence of and factors associated with placental malaria in the White Nile State: a cross-sectional study.

Malaria during pregnancy can lead to maternal and perinatal adverse effects. Despite the preventive measures, recent research has shown that malaria during pregnancy is still a threatening health problem, especially in Sub-Saharan African countries. The current study was conducted to determine the prevalence of and factors associated with placental malaria in Rabak Hospital in central Sudan. A cross-sectional study was conducted from September to October 2021. Pregnant women who delivered at the Rabak Maternity Hospital in Central Sudan were included. A questionnaire was used to gather both obstetric and socio-demographic information. Blood films for malaria were prepared using the maternal, placental, and cord blood, and a placental histology was performed. A logistic regression analysis was performed. For the 208 women, the medians (interquartile range) of their age and parity were 25 (21.0 ‒30.0) years and 2 (1‒4), respectively. Twenty-five (12.0%) of the women had used insecticide-treated nets. Active infection, active-chronic infection, and past-chronic infection were detected in four (1.9%), five (2.4%), and 35 (16.8%) placentas, respectively. One hundred and sixty-four (78.8%) placentas showed no signs of infection. Logistic regression analysis showed that none of the examined factors (age, parity, education, antenatal care level, use of insecticide-treated nets, and blood group) was associated with placental malaria. Malaria affects 20% of pregnant women, regardless of their age and parity. Preventative measures should therefore be encouraged in this area.

Ownership and use of insecticide-treated nets in Myanmar: insights from a nationally representative demographic and health survey

BackgroundMalaria poses a substantial public health threat in Myanmar, indicating the need for rigorous efforts to achieve elimination of the disease nationwide by 2030. The use of insecticide-treated nets (ITNs) forms part of a pivotal strategy for preventing transmission. This study explored the ownership and use of ITNs in Myanmar and identified factors associated with non-use of ITNs.MethodsHousehold datasets from the 2015–2016 Myanmar Demographic and Health Survey were utilised, which encompassed all household members except children under the age of five. Descriptive statistics and inferential tests, including simple and multiple logistics regression models and Pearson correlations, were employed for analysis. All analyses, taking the two-stage stratified cluster sampling design into account, used weighting factors and the “svyset” command in STATA. The ownership and use of bed nets were also visualised in QGIS maps.ResultsAmong the 46,507 participants, 22.3% (95% CI 20.0%, 24.5%) had access to ITNs, with only 15.3% (95% CI 13.7, 17.1%) sleeping under an ITN the night before the survey. Factors associated with the non-use of ITNs included age category (15–34 years—aOR: 1.17, 95% CI 1.01, 1.30; 50+ years—aOR: 1.19, 95% CI 1.06, 1.33), location (delta or lowland—aOR: 5.39, 95% CI 3.94, 7.38; hills—aOR: 1.80, 95% CI 1.20, 2.71; plains—aOR: 3.89, 95% CI 2.51, 6.03), urban residency (aOR: 1.63, 95% CI 1.22, 2.17), and wealth quintile (third—aOR: 1.38, 95% CI 1.08, 1.75; fourth—aOR: 1.65, 95% CI 1.23, 2.23; fifth—aOR: 1.47, 95% CI 1.02, 2.13). A coherent distribution of the ownership and use of ITNs was seen across all states/regions, and a strong correlation existed between the ownership and use of ITNs (r: 0.9795, 95% CI 0.9377, 0.9933, alpha < 0.001).ConclusionsThis study identified relatively low percentages of ITN ownership and use, indicating the need to increase the distribution of ITNs to achieve the target of at least one ITN per every two people. Strengthening the use of ITNs requires targeted health promotion interventions, especially among relatively affluent individuals residing in delta or lowland areas, hills, and plains.

Prevention of Malaria in Pregnant Women and Its Effects on Maternal and Child Health, the Case of Centre Hospitalier de Kingasani II in the Democratic Republic of the Congo.

This study aimed to evaluate scientific evidence of the benefit of the use of insecticide-treated nets (ITNs) and Intermittent preventive treatment (IPT) on the birth weight of newborns and the hemoglobin level of the mother when used to prevent malaria during pregnancy. This cross-sectional analytical study was conducted on 467 hospitalized women in the Maternity Ward of Centre Hospitalier de Kingasani II, in the Democratic Republic of the Congo. Data were collected using a structured questionnaire that was pre-tested during a face-to-face interview. Apart from basic statistics, the chi-square test was used to compare proportions. Multivariate analysis (logistic regression) was used to identify variables significantly associated with the 95% confidence interval (CI). The ITN ownership rate was 81% (95% CI: 77-84) and the ITN use rate was 66% (95% CI: 62-70). Sixty-five percent (95% CI: 60-69) reported having received at least three doses of IPT during pregnancy with sulfadoxine-pyramethemine (IPTp-SP). There was a statistically significant difference in hemoglobin levels between hospitalized women who did not use the ITN (9.4 g/dL IIQ: 8.7-9.9) and those who did (11 g/dL IIQ: 9.8-12.2). The non-use of the ITN was associated with low birth weight (aOR = 3.6; 95% CI: 2.1-6.2; p < 0.001) and anemia in pregnant women (cOR = 2.41; 95% CI: 1.16-5.01; p = 0.018). The use of ITN and taking at least three doses of ITP during pregnancy are associated with good birth weight. The number of doses of IPTp received during antenatal care is associated with the maternal hemoglobin level in the third trimester of pregnancy.

Exploring a Moderation Analysis in the Interactive Relationship between the Determinants of ITN use in Ghana. A Multi-Level Analysis Based on the DHS 2019 Malaria Indicator Survey

Background: Insecticide-treated mosquito net (ITN) use is considered a highly efficient vector-control strategy for reducing malaria transmission and while this tool is widely available in vast malaria-endemic areas, there is still a gap in determining its effective use given household access and ownership. Malaria analysis posits that although the availability of ITNs in a household is a prerequisite for use, it does not determine its effective use. Rather, the determinants of ITN use are a result of the complex interplay of factors at the various socioecological levels (i.e., the individual, household, community, and net levels). These complexities are context-specific and shape the behavioral choices of ITN users. This study explores the context-specific factors associated with ITN use and focuses on the interactive relationships among the individual determinants of ITN use. A conceptual approach is developed to test the interactive effect of ITNs in the household on the relationship between the number of children under five years and ITN use by household members in Ghana. Method: Survey data with a sample size of 10,997 were drawn from the Ghana 2019 Demographic and Health Survey and the 2020 Malaria Indicator Survey to analyse the interactive relationship among individual, household, community, and net level variables. The relationship between these variables was assessed in a multivariate setting via a linear regression model. A further analysis involved a moderation effect of the number of ITNs on the relationship between the number of children under five years and household members´ ITN use using a single moderation model. Results: From the data analyses, the number of children under five years was positively associated with household members' ITN use (OR = 0.29, p &lt; .001), and the number of ITNs was negatively associated with ITN use (OR = -06, p &lt; .05) and was positively associated with the number of children under five years (OR = .23, p &lt; .05). Gender was positively associated with ITN use and the number of children under five years and negatively associated with the number of ITNs. Increasing age was associated with decreased ITN use, number of children, and number of ITNs respectively. An increasing wealth index was associated with decreased ITN use, the number of children under five years, and the number of ITNs. The region was not significant with ITN use but associated with the number of children under five years. Place of residence was associated with ITN use, number of children under five years, and number of ITNs. A moderation effect of the number of ITNs (OR = -.05, p &lt; .001) on the relationship between the number of children under five years and household members' ITN use was reported. Conclusion: The number of children under five years influenced household members´ ITN use but this relationship was moderated by the number of ITNs in the household. The proportion of the number of children under five years was moderately different for a high and low household ITN availability whereby ITN use decreased with higher ITN ownership and increased with lower ownership. Future research should focus on more moderation analysis to better understand the complexity of interactions between individual, household, community, and net-level factors that determine ITN use. This might help to better understand and engage better-targeted action in increasing effective ITN use in households relevant to their needs.

A dynamic game of lymphatic filariasis prevention by voluntary use of insecticide treated nets

Lymphatic filariasis (LF) has been targeted for elimination as a public health concern by 2030 with a goal to keep the prevalence of LF infections under the 1% threshold. While mass drug administration (MDA) is a primary strategy recommended by WHO, the use of insecticide treated nets (ITN) plays a crucial role as an alternative strategy when MDA cannot be used. In this paper, we use imitation dynamics to incorporate human behavior and voluntary use of ITN into the compartmental epidemiological model of LF transmission. We find the equilibrium states of the dynamics and the ITN usage as it depends on epidemiological parameters and the cost of ITNs. We investigate the conditions under which the voluntary use of ITNs can keep the LF prevalence under the 1% threshold. We found that when the cost of using the ITNs is about 105 smaller than the perceived cost of LF, then the voluntary use of ITNs will eliminate LF as a public health concern. Furthermore, when the ITNs are given away for free, our model predicts that over 80% of the population will use them which would eliminate LF completely in regions where Anopheles are the primary vectors.

Insecticide-treated bed nets and residual indoor spraying reduce malaria in areas with low transmission: a reanalysis of the Maltrials study

BackgroundThe malaria incidence data from a malaria prevention study from the Rift Valley, Central Ethiopia, were reanalysed. The objective was to investigate whether including an administrative structure within the society, which may have required consideration in the protocol or previous analysis, would provide divergent outcomes on the effect measures of the interventions.MethodsA cluster-randomized controlled trial lasting 121 weeks with 176 clusters in four groups with 6071 households with 34,548 persons was done: interventions combining indoor residual spraying (IRS) and insecticide-treated nets (ITNs), IRS alone, ITNs alone and routine use. The primary outcome was malaria incidence. A multilevel negative binomial regression model was employed to examine the impact of the kebele (smallest administrative unit) and the proximity of homes to the primary mosquito breeding sites as potential residual confounders (levels). The study also assessed whether these factors influenced the effect measures of the interventions.ResultsThe study's initial findings revealed 1183 malaria episodes among 1059 persons, with comparable effects observed across the four intervention groups. In the reanalysis, the results showed that both ITN + IRS (incidence rate ratio [IRR] 0.63, P < 0.001) and ITN alone (IRR 0.78, P = 0.011) were associated with a greater reduction in malaria cases compared to IRS (IRR 0.90; P = 0.28) or the control (reference) group. The combined usage of IRS with ITN yields better outcomes compared to the standalone use of ITN and surpasses the effectiveness of IRS in isolation.ConclusionThe findings indicate that implementing a combination of IRS and ITN and also ITN alone decrease malaria incidence. Furthermore, there was an observed synergistic impact when ITN and IRS were used in combination. Considering relevant social structures as potential residual confounders is of paramount importance.Trial registration: PACTR201411000882128 (08 September 2014).

Relative effects of climate factors and malaria control interventions on changes of parasitaemia risk in Burkina Faso from 2014 to 2017/2018

BackgroundIn Burkina Faso, the prevalence of malaria has decreased over the past two decades, following the scale-up of control interventions. The successful development of malaria parasites depends on several climatic factors. Intervention gains may be reversed by changes in climatic factors. In this study, we investigated the role of malaria control interventions and climatic factors in influencing changes in the risk of malaria parasitaemia.MethodsBayesian logistic geostatistical models were fitted on Malaria Indicator Survey data from Burkina Faso obtained in 2014 and 2017/2018 to estimate the effects of malaria control interventions and climatic factors on the temporal changes of malaria parasite prevalence. Additionally, intervention effects were assessed at regional level, using a spatially varying coefficients model.ResultsTemperature showed a statistically important negative association with the geographic distribution of parasitaemia prevalence in both surveys; however, the effects of insecticide-treated nets (ITNs) use was negative and statistically important only in 2017/2018. Overall, the estimated number of infected children under the age of 5 years decreased from 704,202 in 2014 to 290,189 in 2017/2018. The use of ITNs was related to the decline at national and regional level, but coverage with artemisinin-based combination therapy only at regional level.ConclusionInterventions contributed more than climatic factors to the observed change of parasitaemia risk in Burkina Faso during the period of 2014 to 2017/2018. Intervention effects varied in space. Longer time series analyses are warranted to determine the differential effect of a changing climate on malaria parasitaemia risk.

MATHEMATICAL MODELING OF THE SPREAD OF VECTOR BORNE DISEASES WITH INFLUENCE OF VERTICAL TRANSMISSION AND PREVENTIVE STRATEGIES

This work is aimed at formulating a mathematical model of the spread of vector-borne diseases with influence of vertical transmission and preventive strategies. Vector borne diseases are caused by viruses, bacteria, and parasites typically conveyed by mosquitoes. Certain illnesses transmitted by vectors include West Nile Virus, Malaria, Zika virus, Dengue fever, Rift valley fever, and Viral encephalitis induced by pathogens like bacteria, viruses, and parasites. The positive solutions of the model are presented and the theory of basic reproduction number was used to study the model dynamical behaviour. When reduces; the diseases are wiped out of the population with time and vice versa. The disease free and endemic equilibria states of the model were determined and investigated to be locally and globally stable.We incorporated the use of Insecticide –Treated Nets (ITN), Indoor Residual Sprayings (IRS) and condom usage as preventive measures in the presence of treatment. Numerical simulations show that complete intervention measures, that is, the use of ITN, IRS and condom usage while placing the infected on treatment have valuable impact on the spread of vector-borne diseases.

Utilization of malaria preventive strategies among pregnant women at Adeoyo Maternity Teaching Hospital, Ibadan, Nigeria

INTRODUCTION: Malaria in pregnancy is associated with a high rate of maternal and perinatal morbidity and mortality. Utilization of preventive strategies during pregnancy is an integral part of controlling the burden of malaria in pregnancy. This study evaluated the malaria preventive strategies utilized and the prevalence of asymptomatic malaria among pregnant women at Adeoyo Maternity Teaching Hospital (AMTH), Ibadan, Nigeria.&#x0D; METHODS: A facility-based descriptive cross-sectional study among 223 pregnant women in Adeoyo Maternity Teaching Hospital, Ibadan, Nigeria. Information on socio-demographic and obstetric characteristics, malaria symptoms, and the preventive strategies utilized were obtained using a structured questionnaire. Descriptive and bivariate analysis using chi-square test and multivariate analysis at 95% confidence interval and p&lt; 0.05 was used to determine the predictors of asymptomatic malaria infection in relation to socio-demographic characteristics and malaria preventive strategies utilized.&#x0D; RESULTS: The mean age was 30±5 years. More than half (53.4%) of them used insecticide-treated nets consistently, 49.3% sprayed the room regularly with insecticides, while the majority (88.3%) reported they maintained a clean environment. However, 11.7% tested positive for the malaria parasite. Consistency in the use of insecticide-treated net (ITN) and participants age were factors associated with malaria occurrence (p=0.01). The use of ITN and being &gt;30 years of age are protective factors against having malaria infection among pregnant women (AOR= 0.34; 95%, CI=0.14-0.84) and (AOR=0.31; 95% CI=0.13-0.76) respectively.&#x0D; CONCLUSION: Irrespective of all other malaria preventive strategies adopted by pregnant women, consistent use of ITN was independently a protective factor against developing malaria in pregnancy.

A mathematical model of visceral leishmaniasis transmission and control: Impact of ITNs on VL prevention and elimination in the Indian subcontinent.

Visceral Leishmaniasis (VL) is a deadly, vector-borne, parasitic, neglected tropical disease, particularly prevalent on the Indian subcontinent. Sleeping under the long-lasting insecticide-treated nets (ITNs) was considered an effective VL prevention and control measures, until KalaNet, a large trial in Nepal and India, did not show enough supporting evidence. In this paper, we adapt a biologically accurate, yet relatively simple compartmental ordinary differential equations (ODE) model of VL transmission and explicitly model the use of ITNs and their role in VL prevention and elimination. We also include a game-theoretic analysis in order to determine an optimal use of ITNs from the individuals' perspective. In agreement with the previous more detailed and complex model, we show that the ITNs coverage amongst the susceptible population has to be unrealistically high (over 96%) in order for VL to be eliminated. However, we also show that if the whole population, including symptomatic and asymptomatic VL cases adopt about 90% ITN usage, then VL can be eliminated. Our model also suggests that ITN usage should be accompanied with other interventions such as vector control.