Net Usage Research Articles

Community benefits of mass distribution of three types of dual-active-ingredient long-lasting insecticidal nets against malaria prevalence in Tanzania: evidence from a 3-year cluster-randomized controlled trial

BackgroundLong-lasting insecticidal nets (LLINs) were once fully effective for the prevention of malaria; however, mosquitoes have developed resistance to pyrethroids, the main class of insecticides used on nets. Dual active ingredient LLINs (dual-AI LLINs) have been rolled out as an alternative to pyrethroid (PY)-only LLINs to counteract this. Understanding the minimum community usage at which these LLINs elicit an effect that also benefits non-users against malaria infection is important.MethodsWe conducted a secondary analysis of a 3-year randomized controlled trial (RCT) in 84 clusters in North-western Tanzania to evaluate the effectiveness of three dual-AI LLINs: pyriproxyfen and alpha(α)-cypermethrin, chlorfenapyr and α-cypermethrin, and the piperonyl-butoxide (PBO) and permethrin compared to α-cypermethrin only LLINs. We measured malaria infection prevalence using 5 cross-sectional surveys between 2020 and 2022. We assessed net usage at the cluster level and malaria infection in children aged from 6 months to 14 years in 45 households per cluster. The trial was registered as a clinical trial on www.clinicaltrials.gov: ClinicalTrials.gov (NCT03554616) on 2018-06-13.ResultsA total of 22,479 children from 12,654 households were tested for malaria using rapid diagnostic tests in January 2020, 2021, & 2022 and July 2020 & 2021. Among non-users, community-level usage of > 40% of dual-AI LLIN was significantly associated with protection against malaria infection: chlorfenapyr arm (OR: 0.44 (95% CI: 0.27–0.71), p = 0.0009), PBO arm (OR: 0.55 (95% CI: 0.33–0.94), p = 0.0277) and pyriproxyfen arm (OR: 0.61 (95% CI: 0.37–0.99), p = 0.0470) compared with non-users in clusters with > 40% usage of pyrethroid-only LLINs. There were indications of some protection against malaria infection to non-users in the chlorfenapyr arm when community-level usage was ≤ 40% (OR: 0.65 (95% CI: 0.42–1.01), p = 0.0528) compared to those living in clusters with > 40% usage of pyrethroid-only LLINs.ConclusionOur study demonstrated that at a community usage of 40% or more of dual-AI LLINs non-users benefited from the presence of these nets. Noticeably, even when usage was ≤ 40% in the chlorfenapyr arm, non-users were better protected than non-users in the higher coverage pyrethroid-only arm. The greater difference in malaria risk observed between users and non-users indicates that LLINs play a crucial role in providing personal protection against malaria infection for the people using the net.

What rural ecological governance goals do local residents prefer? Evidence from Hainan, China

Rural ecosystems restoration requires the joint participation of rural residents and government in governance. This study aims to analyze whether rural ecological governance goals are consistent with rural residents' preferences and how they affect rural residents' utility levels, which are key to rural residents' ecological governance participation behavior. Using survey data from 653 rural residents in Hainan Island, China, this paper applies a choice experiment method and a random parameter logit model to identify differences in rural residents' preferences for different rural ecological governance policy goals and their governance participation behaviors. The results show that increasing the coverage rate of sewage treatment facilities, reducing fertilizer and pesticide application, and increasing rural biodiversity can significantly enhance rural residents' ecological governance participation utility, thereby promoting their choice of ecological governance options. Rural residents' participation behavior in rural ecological governance is also influenced by individual and household characteristics such as ethnicity, labor size, net farm income, ICT usage, and ecological knowledge level. Based on these findings, policymakers should strengthen communication of governance policies and objectives, respect rural residents' policy goal preferences, prioritize the implementation of rural ecological governance models that increase the coverage of wastewater treatment facilities, reduce fertilizer and pesticide application, and increase rural biodiversity, and rely on ICT devices to popularize ecological knowledge among rural residents.

Perception of caregivers on ITNs utilisation and its effectiveness among children under 5 years of age in Chikwawa district, Malawi

BackgroundIn 2020, Malawi had 6.9 million malaria cases and 2551 deaths, mainly in children under five years of age. The 2017–2022 Malawi malaria control strategic plan promoted the consistent use of insecticide-treated nets through free distribution and mass campaigns. Despite widespread availability of the control strategy plan, Chikwawa District continues to suffer from high malaria burden especially among under five children, due to inconsistent insecticide-treated (ITN) net usage. For this reason, this study aimed at exploring caregivers’ perceptions on insecticide-treated net utilisation and also find out about its effectiveness among those who consistently use them.MethodsThis study used a sequential exploratory mixed methods design. The data used for quantitative analysis was drawn from the population of under-five children’s caregivers within the catchment area of Chikwawa district hospital. The sample size was 96 participants, as determined by Cochran’s formula. The data collection lasted from December 2023 to April 2024 and included four in-depth interviews and three focus group discussions to address the objectives qualitatively.ResultsThe study revealed that 91.67% of households used ITNs, with 87.50% using them daily. The significant factors influencing ITN utilisation included the number of nets, user satisfaction, perceived impact, user habits, acquisition method, and usage frequency (all p values < 0.001). Under-five malaria cases were also significant (p = 0.025). The odds of the perceived net impact influencing utilisation were 4.956 times greater. Non-usage was due to heat, quality concerns, limited access, breathing difficulties, health conditions such as asthma, and misconceptions about net treatment.ConclusionThe study revealed a strong belief in insecticide-treated net efficacy. However, some challenges such as access, durability, and misinformation of insecticide-treated nets were discovered. These challenges affected utilisation of insecticide-treated nets in agreement with some literature reviewed. The insights found in this study will help policymakers in addressing health interventions for the reduction of malaria cases in Malawi.

Prevalence of Malaria Infection among Pregnant Women Attending Antenatal Clinic in Nnamdi Azikiwe University Teaching Hospital, Nnewi

Malaria is a major health problem affecting people in the tropics and sub-tropical regions of the world. This cross-sectional hospital-based study was carried out to determine the prevalence of malaria infection among pregnant women attending a tertiary hospital in Nnewi, Anambra State, Nigeria. A total of 100 venous blood samples were collected from pregnant women into EDTA tubes and examined using field-stained thick and thin films for identification of malaria parasites. Demographic information such as age, trimester and insecticide-treated nets usage was obtained using a structured questionnaire. Data was analyzed using Statistical Package for the Social Sciences version 22. The chi-square test was used to determine the difference among the variables studied and P≤ 0.05 were considered significant. Out of the 100 blood samples examined, 27 were infected and had an overall prevalence of 27%. Women within the age bracket of 31-35 years had the highest prevalence rate 11(36.7%) while no infection was recorded in the 41-45 years age group 0(0.0%). Pregnant women in their first trimester had the highest infection prevalence of 13(35.1%) while those in their third trimester had the least prevalence of 5(17.9%). In relation to ITN’s usage, pregnant women who don’t normally sleep under ITNs had the highest infection prevalence 23(31.5%) while those who usually sleep under ITNS had the least prevalence rate 4(14.8%). It is pertinent to periodically check the malaria infection status of pregnant women attending antenatal services. Prophylactic treatment should be routinely administered to avoid pregnancy complications due to malaria infection.

PREVALENCE OF MALARIA PARASITES AMONG PREGNANT WOMEN ATTENDING GENERAL HOSPITAL GARAKU, KOKONA LOCAL GOVERNMENT, NASARAWA STATE

Malaria remains a significant health concern, particularly among pregnant women in various regions of Nigeria, including the Kokona metropolis. This study aimed to determine the prevalence of malaria among pregnant women in Garaku, Kokona LGA, Nasarawa State, and to assess the diagnostic accuracy of Microscopy versus Rapid Diagnostic Test (RDT). Blood samples were collected from 150 pregnant women in the Kokona Local Government Area and analyzed using both Microscopy and RDT. Data were analyzed using SPSS software version 23.0, with statistical significance set at P &lt; 0.05. The overall prevalence of malaria was found to be 31.33%, with the highest prevalence observed among women in their first trimester (36.71%). Microscopy demonstrated a higher positivity rate compared to RDT. Additionally, women aged 31-40 years exhibited the highest susceptibility, with a prevalence of 42.11%. However, no significant difference was noted in malaria prevalence based on the usage of mosquito nets or parity status. The study underscores the high prevalence of malaria among pregnant women in the region, emphasizing the need for enhanced intervention strategies. Microscopy remains a more reliable diagnostic tool than RDT. Early antenatal booking and regular preventive measures are crucial to mitigating the adverse effects of malaria during pregnancy. Furthermore, environmental sanitation efforts should be intensified to reduce mosquito breeding and subsequent malaria transmission.

Prevalence and predictors of malaria in pregnant women in Sub-Saharan Africa: a systematic review and meta-analysis

Malaria remains a significant threat to pregnant women in sub-Saharan Africa. This systematic review and meta-analysis aims to estimate the prevalence and identify predictors of malaria infection among pregnant women in the region. Following preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, a comprehensive search of PubMed Central, Google Scholar, EMBASE, ScienceDirect, and Cochrane Library was conducted, including 15 studies published between 2013 and 2023. The pooled prevalence of malaria, calculated using a random-effects model, was 19.0% (95% CI: 0.13-0.26), with heterogeneity (I²=81.9%) reflecting geographical and climatic diversity. Prevalence rates ranged from 6.4% in Burkina Faso to 36.4% in Tanzania. Asymptomatic cases had a prevalence of 19.0% (95% CI: 0.10-0.38), while symptomatic cases were slightly lower at 17.0% (95% CI: 0.12-0.23). Predictors of malaria included maternal age, parity, insecticide-treated net usage, intermittent preventive treatment, trimester-specific risk, and education level. These findings underscore the need for targeted, context-specific interventions to mitigate malaria risk among pregnant women in sub-Saharan Africa and inform effective malaria control strategies.

New Strides in Prevention of Malaria during Pregnancy Present Multitudinous Opportunities.

Pregnant women are at a higher risk of developing complications from malaria, a mosquito-borne disease caused by Plasmodium parasites, resulting in considerable maternal and infant morbidity and mortality. Malaria in pregnancy causes unfavorable and life-threatening outcomes for both the mother and fetus not limited to maternal anemia, hypoglycaemia, cerebral malaria, pulmonary edema, and puerperal sepsis. WHO recommends wide-ranging strategies for this detrimental but preventable disease; however, numerous challenges persist in ensuring high uptake of preventive therapies, effective usage of insecticide-treated bed nets, and early initiation and optimal antenatal care coverage for pregnant women. This work distils recent global advances in preventive strategies for malaria in pregnancy. We discuss three mainstay interventions by WHO, viz. intermittent preventive treatment of malaria in pregnancy (IPTp), utilization and outcomes of insecticide-treated bed nets (ITNs), and headways in malaria case management using therapeutic drugs. We cover multitudinous facets of antenatal care, WHO-advised community-based delivery of IPTp (c-IPTp), intermittent screening and treatment for malaria in pregnancy (ISTp), a malaria vaccine for pregnant women, and auxiliary factors that are crucial for improving prevention outcomes. Despite the reduction in malaria globally, malaria in pregnancy remains a prevalent issue in endemic areas, which warrants strengthening of preventative strategies. This work attempts to consolidate pivotal observations of the prevention of malaria during pregnancy by highlighting key advances, priority areas, new opportunities, research gaps, and challenges that need to be addressed to ensure improved outcomes in pregnant women infected with malaria.

Assessment of Risk Factors Associated with Malaria Infection Among Adult Populations in Selected Internally Displaced Camps in Goma, North Kivu Province, Dr. Congo

Malaria remains a significant public health concern in many parts of the world, particularly in Africa. The Democratic Republic of the Congo (DRC) is one of the countries most heavily affected by malaria, with millions of cases reported annually. In the Eastern region of the DRC, ongoing conflict has resulted in large numbers of people living in precarious conditions within IDP camps, where the risk of malaria transmission is heightened due to unsuitable housing conditions, lack of bed net, overcrowded and unsanitary conditions with limited access to essential healthcare services. This study aims to assess the risk factors associated with malaria infection among adult populations in the Kashaka and Shabindu IDP camps in Goma, North Kivu Province. The study employed a cross-sectional design using a mixed-method approach. Data were collected from 371 households through interviews and medical record reviews. Chi-square tests were performed for bivariate analysis, and then logistic regression to evaluate the impact of multiple variables simultaneously. All participants pointed to mosquitoes as the causal agent. Around 97.8% confirmed that fever is the main symptom followed by chills (75.2%), headache (54.5%), and sweating (10.2%). Bed net was identified as a preventive measure at (100%), mosquito repellents (71.7%), and Indoor residual spraying (68;2%). Approximately 43.9% of households had at least one case of malaria with an increasing incidence in April (26.7%) and October (35.9%). The most significant factors affecting the spread of malaria were gender (OR: 1.73; p-value &lt; 0.001), lack of bed net (OR: 5.231; p-value &lt; 0.001), outdoor activities at night (OR: 0.661; p-value = 0.0364), and being close to sanitation facilities (OR: 2.458; p-value = 0.0013). These underscore the critical need for targeted malaria prevention measures, including increased bed net availability and usage, enhanced sanitation infrastructure, and heightened awareness about the dangers of outdoor nighttime activities.

Association between malaria parasitemia with usage of insecticide-treated nets (ITNS) among pregnant and nursing mothers accessing Lokuwa Primary Health Care (PHC) facility, Mubi, Nigeria

Association between malaria parasitemia with usage of insecticide-treated nets (ITNS) among pregnant and nursing mothers accessing Lokuwa Primary Health Care (PHC) facility, Mubi, Nigeria

Optimization of a hybrid renewable energy system for off-grid residential communities using numerical simulation, response surface methodology, and life cycle assessment

This paper presents an optimized hybrid renewable energy system tailored for off-grid residential communities, integrating wind, solar, and hydrogen technologies to meet electricity, cooling, heating, and water needs. The proposed optimization methodology combines numerical simulation, response surface methodology (RSM), and life cycle assessment (LCA), ensuring robust performance across diverse conditions. Key components include fuel cells, reverse osmosis systems, heat pumps, photovoltaic/thermal solar collectors, wind turbines, and hydrogen generation systems. The optimization process targets critical variables such as PVT panel area, the number of wind turbines, and fuel cell power. The optimal configuration was found to include 24 small-scale wind turbines, 159.46 m2 of PVT collectors, and 79.73 kW of fuel cell power. This configuration generated surplus electricity with net electricity usage (NEU) values of −123084.27 kWh/year in New York, −224245.29 kWh/year in Forks, and −215949.30 kWh/year in Santa Barbara. Additionally, the optimized systems achieved a significant reduction in life cycle cost (LCC), with Forks showing the lowest LCC at 304428.97 USD. The environmental impact was also minimized using the novel optimization approach, with the optimized systems achieving negative 100-year global warming potential (GWP100) values, indicating a net reduction in greenhouse gas emissions.

Durability of PBO nets (Olyset Plus®), 12 months after their distribution in Bertoua, Cameroon

BackgroundThe rapid spread of pyrethroid resistance has led to a change in strategy, going from pyrethroid-based nets to PBO + pyrethroid-treated nets. Although these new nets may significantly improve the control of pyrethroid-resistant mosquitoes, their durability in the field remain not yet well documented. This study investigates the durability and washing resistance of Olyset-Plus nets in the city centre and rural areas of Bertoua, Cameroon. In each site, a semi-structured questionnaire was administered to at least 190 households with an Olyset-Plus net. Factors such as net use, physical integrity and bioefficacy were recorded. Bioassays were conducted on the collected nets to assess their bioefficacy and resistance to washing. They were tested against wild Anopheles gambiae sensus lato (s.l.). Unused nets and the Kisumu strain were used as controls. Washing and cone testing of the nets was carried out according to standard WHO protocols. ResultsA high rate of net use by children was recorded in the urban area (89.1% (106/119)) compared to the rural area (39.7% (118/297)). The majority of Olyset-Plus nets inspected 82.2% (162/197) in the rural area and 88% (206/234) in the urban centre were in good condition (Hole Index<64). Only 5.6% and 6.8% of nets were badly torn in rural and urban sites respectively. Nets were washed more regularly in the urban centre. 88.1% of urban dwellers reported having washed their nets at least once compared to only 62% of rural dwellers. Bioefficacy tests with nets indicated a mortality rate ranging from 66% for unwashed nets to 86.7% for nets washed at least once. Bioefficacy varied significantly in the city of Bertoua according to net washing frequency, soaking time, soap type and drying location, whereas in the rural village, only washing(washed or unwashed) and soaking status (soaked or unsoaked) significantly influenced the bioefficacy of Olyset-Plus nets. ConclusionsThis study revealed different handling practices of bed nets in rural and urban settings which could significantly affect Olyset-Plus nets bio-efficacy and durability. Routine monitoring and sensitization of communities to best practices concerning bed nets usage and handling during mass distribution might enhance the net durability in the community.

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

KNOWLEDGE EVALUATION OF MOSQUITO CONTROL PRACTICES WITHIN THE CENTRAL REGION OF JIGAWA STATE, NORTH-WEST NIGERIA

In order to mitigate and manage life-threatening mosquito-borne diseases such as malaria, Dengue, and lymphatic filariasis, both socio-demographic factors and the collective vector control knowledge within the community are pivotal. Hence, the objective of the current study is to evaluate the awareness and understanding of mosquito control practices in specific communities located in Jigawa State, North-west Nigeria. A cross-sectional study was conducted in which 60 structural questionnaires were distributed in the three selected communities. In each village, 20 questionnaires were randomly shared and captured information on Demographical characteristics, House characteristics, Use of mosquito net etc. Among the 60 respondents, only 17(28.3%) of the respondents were participating in community sanitation, majority of respondents 56(93.3%) were found to keep water at home. However, usage of long-lasting insecticide nets (LLINs) on daily basis were recorded significantly highest 48(80%). We therefore recommend promotion of the significance of environmental sanitation as a primary measure for controlling mosquito-borne diseases among them.

Spatial Downscaling of Satellite-Based Soil Moisture Products Using Machine Learning Techniques: A Review

Soil moisture (SM) is a key variable driving hydrologic, climatic, and ecological processes. Although it is highly variable, both spatially and temporally, there is limited data availability to inform about SM conditions at adequate spatial and temporal scales over large regions. Satellite SM retrievals, especially L-band microwave remote sensing, has emerged as a feasible solution to offer spatially continuous global-scale SM information. However, the coarse spatial resolution of these L-band microwave SM retrievals poses uncertainties in many regional- and local-scale SM applications which require a high amount of spatial details. Numerous studies have been conducted to develop downscaling algorithms to enhance the spatial resolution of coarse-resolution satellite-derived SM datasets. Machine Learning (ML)-based downscaling models have gained prominence recently due to their ability to capture non-linear, complex relationships between SM and its driving factors, such as vegetation, surface temperature, topography, and climatic conditions. This review paper presents a comprehensive review of the ML-based approaches used in SM downscaling. The usage of classical, ensemble, neural nets, and deep learning methods to downscale SM products and the comparison of multiple algorithms are detailed in this paper. Insights into the significance of surface ancillary variables for model accuracy and the improvements made to ML-based SM downscaling approaches are also discussed. Overall, this paper provides useful insights for future studies on developing reliable, high-spatial-resolution SM datasets using ML-based algorithms.

Molecular Investigation of Cutaneous Leishmaniasis (CL) from Biopsy Samples: A Case Study of District Mohmand, KPK

Background: Leishmaniasis is a complex disease with diverse clinical manifestations and remains a significant public health concern, particularly in tropical and subtropical regions around the world. Cutaneous leishmaniasis (CL), being the most prevalent type, causes significant morbidity and social stigmatization. District Mohmand, an arid mountainous region in the KPK province of Pakistan, has an increased burden of CL with no prior molecular study reported on it in this region of Pakistan. Methods: The current study investigated CL using molecular techniques to detect and evaluate the risk factors associated with this disease in the affected population of District Mohmand. The study was conducted at Tehsil Head Quarter Hospital Mamad Gat, District Mohmand. Results: Out of 150 samples, 106 were found to be positive and 44 turned out to be negative under microscopy, while 122 were positive and 28 were negative using PCR analysis. Statistical analysis revealed that children between the ages of 1 and 10 years are frequently affected. Similarly, male gender is affected to a greater degree as compared to the female gender. Furthermore, the proportion of facial lesions was 62%, followed by upper limbs (17%), lower limbs (17%), and lesions on multiple sites (4%). These numbers are associated with various factors, such as the presence of domestic animals, lack of bed net usage, migration, and the type of wall and roof. Conclusion: The study concluded that children are more prone to infection. The PCR method was found to be more reliable for diagnosing CL as compared to microscopy.

Catch composition, catch per unit effort (CPUE) and species selectivity of fishing gears on multi-species Kaptai Lake in Bangladesh

Kaptai Lake, the largest artificial reservoir in Southeast Asia, is home to a diverse fish fauna that supports thousands of livelihoods and is distinguished by multi-species and multi-gear fisheries. In Kaptai Lake, the gear-based catch composition, catch rate and distribution pattern are little known. From August 2020 to April 2021, a nine-month study was conducted in five upazilas using direct catch assessment surveys and fishing effort surveys from four fishing gears, namely seine nets, gill nets, lift nets, and push nets. A total of 49 morpho-species from 22 families were found, with three species from the Clupeidae accounting for 93.63 % of the catch in all gear combined. The total catch composition and CPUE were higher in seine nets (75.07 %, 13.86 ± 1.8 kg/gear/trip respectively) and lower in lift nets (4.97 %, 1.01 ± 0.21 kg/gear/trip) and showed significant differences among gears, except sampling sites whereas CPUE was higher in Naniarchar for seine nets (17.29 ± 8.89 kg/gear/trip) and lower in Langadu for lift nets (0.62 ± 0.25 kg/gear/trip). Seine nets captured more species, and the number of species increased significantly as CPUE increased. Our study assessed four gears that targeted different fish species with little overlap in leading species; seine nets and gill nets primarily targeted Clupeidae (96.53 % and 41.69 %, respectively), whereas lift nets and push nets primarily targeted Cyprinidae and Palaemonidae (38.93 % and 99.37 % respectively). The observed abundance and variety of fish species captured in gill nets suggest a significant overlap in the selectivity of this fishing method with that of lift nets. Due to the varying contributions of sites and gears, the nMDS ordination pattern reveals a weak spatial variation in catch composition. According to the SIMPER results, Bagridae, Gobiidae, and Ambassidae were the most significant contributors to site grouping patterns across all gears. Furthermore, the findings indicate that the catch composition does not follow the typical pattern of spatial variation. By implementing measures to eliminate or decrease the usage of small mesh nets, there is expected to be a corresponding decrease in the capture of small fish. Additionally, this action will help mitigate the issue of overlapping selectivity among the current fishing gears. Our findings provide baseline data on the potential efficacy of gear limitation and suggest a gear-based management strategy.

Modeling time to death for under-five children in Malawi using 2015/16 Demographic and Health Survey: a survival analysis

BackgroundMalawi has one of the highest under-five mortality rates in Sub Sahara Africa. Understanding the factors that contribute to child mortality in Malawi is crucial for the development and implementation of effective interventions to reduce child mortality. The aim of this study is to use survival analysis in modeling time to death for under-five children in Malawi. In turn, identify potential risk factors for child mortality and inform the development of interventions to reduce child mortality in the country.MethodThis study used data from all births that occurred in the five years leading up to the 2015/16 Malawi Demographic and Health Survey. The Frailty hazard model was applied to predict infant survival in Malawi. In this analysis, the outcome of interest was death and it had two possible outcomes: "dead" or "alive". Age at death was regarded as the survival time variable. Infants who were still alive at the time of the study as of the day of the interview were considered as censored observations in the analysis.ResultsA total of 17,286 live births born during the 5 years preceding the survey were analysed. The study found that the risk of death was higher among children born to mothers aged 30–39 and 40 or older compared to teen mothers. Infants whose mothers attended fewer than four antenatal care visits were also found to be at a higher risk of death. On the other hand, the study found that using mosquito nets and early breastfeeding were associated with a lower risk of death, as were being male and coming from a wealthier household.ConclusionThe study reveals a notable decline in infant mortality rates as under-five children age, underscoring the challenge of ensuring newborn survival. Factors such as maternal age, birth order, socioeconomic status, mosquito net usage, early breastfeeding initiation, geographic location, and child's sex are key predictors of under-five mortality. To address this, public health strategies should prioritize interventions targeting these predictors to reduce under-five mortality rates.

Identifying childhood malaria hotspots and risk factors in a Nigerian city using geostatistical modelling approach

Malaria ranks high among prevalent and ravaging infectious diseases in sub-Saharan Africa (SSA). The negative impacts, disease burden, and risk are higher among children and pregnant women as part of the most vulnerable groups to malaria in Nigeria. However, the burden of malaria is not even in space and time. This study explores the spatial variability of malaria prevalence among children under five years (U5) in medium-sized rapidly growing city of Akure, Nigeria using model-based geostatistical modeling (MBG) technique to predict U5 malaria burden at a 100 × 100 m grid, while the parameter estimation was done using Monte Carlo maximum likelihood method. The non-spatial logistic regression model shows that U5 malaria prevalence is significantly influenced by the usage of insecticide-treated nets—ITNs, window protection, and water source. Furthermore, the MBG model shows predicted U5 malaria prevalence in Akure is greater than 35% at certain locations while we were able to ascertain places with U5 prevalence > 10% (i.e. hotspots) using exceedance probability modelling which is a vital tool for policy development. The map provides place-based evidence on the spatial variation of U5 malaria in Akure, and direction on where intensified interventions are crucial for the reduction of U5 malaria burden and improvement of urban health in Akure, Nigeria.

A Review of Bed Nets Usage and Sewerage Conditions as Risk Factors for Lymphatic Filariasis in Developing Countries

Introduction: Lymphatic filariasis, a neglected tropical disease (NTD), is a parasitic disease caused by microscopic worms that live only in the human lymphatic system. Mosquitoes, as vectors of lymphatic filariasis, play an important role in the prevention of this disease. The aim of this study was to identify agent, vector, and physical environment risk factors for filariasis in developing countries through a literature review. Discussion: This study was conducted using the narrative literature review method. The main sources for this study were articles from Google Scholar, Research Gate, PubMed, Springer, Scopus, and DOAJ databases. The criteria for articles were published between 2012 and 2022, observational studies including cross-sectional, case-control, and cohort designs, open access, and articles were organized according to STROBE guidelines. This study showed that from a total of 100 articles found, 14 articles met the predetermined criteria. Wuchereria bancrofti is the most common agent of filariasis. Culex and Anopheles are the vectors. The presence of bed nets and sewerage conditions were physical environment risk factors for filariasis in developing countries. Conclusion: Prevention of filariasis can be achieved by using mosquito nets or insect repellent when sleeping at night. In addition, open drains should be cleaned regularly to prevent them from becoming breeding sites for mosquitoes as vectors.

Malaria incidence and prevalence: An ecological analysis through Six Sigma approach

Malaria is the leading cause of death globally, especially in sub-Saharan African countries claiming over 400,000 deaths globally each year, underscoring the critical need for continued efforts to combat this preventable and treatable disease. The objective of this study is to provide statistical guidance on the optimal preventive and control measures against malaria. Data have been collected from reliable sources, such as World Health Organization, UNICEF, Our World in Data, and STATcompiler. Data were categorized according to the factors and sub-factors related to deaths caused by malaria. These factors and sub-factors were determined based on root cause analysis and data sources. Using JMP 16 Pro software, both linear and multiple linear regression were conducted to analyze the data. The analyses aimed to establish a linear relationship between the dependent variable (malaria deaths in the overall population) and independent variables, such as life expectancy, malaria prevalence in children, net usage, indoor residual spraying usage, literate population, and population with inadequate sanitation in each selected sample country. The statistical analysis revealed that using insecticide treated nets (ITNs) by children and individuals significantly decreased the death count, as 1,000 individuals sleeping under ITNs could reduce the death count by eight. Based on the statistical analysis, this study suggests more rigorous research on the usage of ITNs.