Mosquito Breeding Sites Research Articles

Effect of Health Education through Community leaders on increased knowledge of Households Regarding malaria control, treatment and prevention in intervention and control villages of New Halfa Locality-Kassala State (2017-2020)

Malaria vector control in Sudan has a long history. The primary vector control interventions are IRS in targeted areas with irrigation schemes, use of LLINs, LSM, and space spraying during an emergency. The present study aimed to assess the effect of Health Education through Community leaders on increased knowledge of Households Regarding malaria control, treatment and prevention in intervention and control villages of New Halfa Locality-Kassala State (2017-2020). Randomized community trials (Controlled intervention study) in New Halfa locality among two communities were randomly assigned to the intervention group which receive health education messages regarding the use of LLINs and control group where there is no health education. A standard Questionnaire was used to collect data from the head of household at each village. The information collected should include the owner and using LLINs, distributed to household. The observation the conditions of LLINs. This Questionnaire was done with committee for integrated vector management - Federal Ministry of Health and WHO. There were association between education level and overall mean knowledge of respondents about mosquito breeding sites, malaria control, uncomplicated malaria symptoms, severe malaria symptoms, and uncomplicated malaria treatment, severe malaria treatment, and fever treatment, p < 0.05. However, the overall mean knowledge was significantly more significant among those who have University education were compared to other level of education, p< 0.05. An increase knowledge scores was observed when pre- and post-test scores on malaria prevention and control were compared. Health education packages.i.e., mass media messages during Bed nets campaigns and the role of community leaders on malaria, was found to have improved knowledge of malaria prevention and control among the studied community.

Effect of Health Education through Community leaders on increased knowledge of Households Regarding malaria control, treatment and prevention in intervention and control villages of New Halfa Locality-Kassala State (2017-2020)

Malaria vector control in Sudan has a long history. The primary vector control interventions are IRS in targeted areas with irrigation schemes, use of LLINs, LSM, and space spraying during an emergency. The present study aimed to assess the effect of Health Education through Community leaders on increased knowledge of Households Regarding malaria control, treatment and prevention in intervention and control villages of New Halfa Locality-Kassala State (2017-2020). Randomized community trials (Controlled intervention study) in New Halfa locality among two communities were randomly assigned to the intervention group which receive health education messages regarding the use of LLINs and control group where there is no health education. A standard Questionnaire was used to collect data from the head of household at each village. The information collected should include the owner and using LLINs, distributed to household. The observation the conditions of LLINs. This Questionnaire was done with committee for integrated vector management - Federal Ministry of Health and WHO. There were association between education level and overall mean knowledge of respondents about mosquito breeding sites, malaria control, uncomplicated malaria symptoms, severe malaria symptoms, and uncomplicated malaria treatment, severe malaria treatment, and fever treatment, p < 0.05. However, the overall mean knowledge was significantly more significant among those who have University education were compared to other level of education, p< 0.05. An increase knowledge scores was observed when pre- and post-test scores on malaria prevention and control were compared. Health education packages.i.e., mass media messages during Bed nets campaigns and the role of community leaders on malaria, was found to have improved knowledge of malaria prevention and control among the studied community.

Larval habitats characterization and population dynamics of Culex mosquitoes in two localities of the Menoua Division, Dschang and Santchou, West Cameroon

BackgroundChoosing an appropriate strategy for mosquito vector control in an eco-climatic facies requires knowledge on vector ecology including population dynamics of species and productivity of the breeding sites. The aim of this study was to characterize Culex mosquitoes breeding places and to determine their population dynamics in two localities (Dschang and Santchou) separated by a forest cliff in the West Region of Cameroon. Field surveys were conducted from November 2019 to June 2020 in Dschang and Santchou. Mosquito breeding sites were georeferenced, and for each breeding site, physical parameters were measured and immature stages were collected. The collected immatures were reared in the laboratory until adult stage. Adult mosquitoes were identified using a stereomicroscope and morphological identification keys.ResultsA total of 44 breeding sites were identified: 24 in Dschang and 20 in Santchou. They were grouped into seven types and were mostly shallow, close to human dwellings, sunny, with organic matters and of anthropogenic nature. A total of 2706 mosquitoes belonging to four genera were identified. Culex genus was the most represented (90.4%) and was made up of Culex pipiens s.l. (61.79%), Culex duttoni (23.17%) and Culex (Culiciomyia) sp. (05.46%). High abundance of Culex species was observed in Santchou (52.71%) compared to Dschang (47.28%), while Dschang (S = 3; H = 0.87; D = 0.54) recorded the greatest diversity compared to Santchou (S = 2; H = 0.23; D = 0.11).ConclusionsThe proliferation and persistence of Culex mosquitoes independently of the breeding sites and localities might be attributable to the poor environmental management which favor the creation mosquito breeding sites. This study highlights the fact that prompt sanitation measures could be undertaken in these two localities to reduce mosquito abundance and the risk of vector-borne diseases.

Flora and fauna of mosquito breeding sites in Akoko South West Local Government Area, Ondo State, Nigeria

This research was carried out between January and July 2021 in Akoko South West Local Government Area of Ondo State, Nigeria. Three sites in each of the eight towns of the Local Government Area were visited and sampled to determine and evaluate the relationship between mosquito species and biotic factors in the mosquito breeding environment. At each site mosquito larvae were collected and flora and fauna at each site were identified. The flora identified included grasses, green Algae, Pride of Barbados and others, while the fauna identified included Damsel flies, Dragon flies, Tadpoles, Midges, Lizard. The Damsel flies, Dragon flies and Tadpoles dominate the fauna distribution chart while Green Algae has the highest percentage of the flora distribution chart followed by grasses and pride of Barbados with the least percentage. The correlation coefficient indicated a positive relationship between larva density and flora while larva density and fauna showed some negative relationship. Adequate understanding of vector ecology is needed to control mosquito particularly in deploying environmental modification around host settlements. This understanding will better serve over deployment of chemicals into such sites that may affect non-targeted organisms.

Bisphenol A acts as developmental agonist in Culex quinquefasciatus Say.

Plastic wastes deposited in canals running through Thiruvananthapuram city have created stagnant waters providing breeding sites for mosquitoes. In the present study, plastic waste-derived bisphenol A (BPA) was quantified from four mosquito breeding sites. During summer rain, the concentration of BPA in the stagnant water samples was found to be between 0.86 and 1.14mg/L, and hence 1mg/L BPA was considered as the environmentally relevant concentration. In the present study, the effect of BPA on the life cycle and metamorphosis of filarial vector, Culex quinquefasciatus Say was elucidated by rearing larvae in water added with BPA at and above the environmentally relevant concentration viz., 1, 2, and 4mg/L. The duration required for adult emergence was reduced from 10 to 8.5days, when the concentration of BPA was increased from 1 to 4mg/L respectively. Our study revealed that embryonic and larval developments were shortened by BPA treatment. BPA also caused a dose-dependent advancement of 20-hydroxyecdysone (20-E) peaks; phospholipase A2 induction; and upregulation of ecdysone receptor gene, EcRA, and ecdysone inducible gene E75A, which culminated in early pupation. No significant difference in sanguivory and fecundity was observed in adult mosquitoes treated with 1mg/L of BPA. Our study reveals that BPA is a developmental agonist of C. quinquefasciatus.

Knowledge and Practices Regarding Chikungunya among Community Members in Urban Area

Chickungunya is a serious and increasing public health problem in tropical and subtropical regions of theworld. It is caused by a group A virus and transmitted by Aedes aegypti and Aedes albopictus. Among thesigns and symptoms were sudden onset of fever headache, joint pain and swelling, inability to walk, fatigue,muscle pain, rash, nausea, chills, anorexia, lumbago, and conjunctivitis. Prevention is entirely upon takingsteps to avoid mosquito bites and eliminating of mosquito breeding sites. This is a cross-sectional descriptivestudy with the aim to study knowledge, attitude and practice of households was conducted in Kassal State,Sudan. 388 households were recruited for the study. A modified structured questionnaire targetinghouseholds was used to collect data and the collected data were analyzed by using computer softwareprogram (SPSS). The results were presented in text, tables and figures. Although, 49.2% and 93% of theparticipants had knowledge concerning modes of transmissions and causative factors, respectively, 61.45and 50.8% had poor or lack knowledge concerning symptoms and signs and method of prevention ofchickungunya, respectively. 69.6% and 68.1% of the participants had favorable attitudes towards perceivingthe severity of chickungunya and dealing with the infected person, respectively. The majority (84.7%) ofthe participants use mosquitoes net as method of prevention and more than half (53.2%) of the participantswere participating in chickungunya prevention program. Household had lack of in-depth knowledge aboutChickungunya causal factors and methods of prevention. Therefore health education and communityawareness can play a role for the control of Chickungunya epidemic.

Correlation of Climate Factors, Population Density, and Larva Free Rate (ABJ) on the Incidence of Dengue Hemorrhagic Fever (DHF) in Kendari City Period 2012-2021

Background: Dengue Hemorrhagic Fever (DHF) is an infectious disease that is endemic in most tropical areas in the world and around 3.5 billion people live in areas where dengue is endemic. A large number of individuals residing in a certain area will facilitate the spread of dengue disease and accelerate the transmission of dengue virus from vectors. Climate is very important for the survival of the Aedes Aegypti mosquito because mosquito breeding sites will increase along with climate change. ABJ shows the density of larvae in an area. Purpose(s): This study aimed to determine the correlation of climate factors, population density, and larva free rate (ABJ) to the incidence of Dengue Hemorrhagic Fever (DHF) in Kendari City in 2012–2021. Methods: This research method was a cross sectional design and Spearman rank correlation analysis using SPSS application. The data used are secondary data in the form of data on rainfall, humidity, temperature, population density, and the incidence of DHF in a period of 10 years (2012-2021) and ABJ in a period 2016 - 2020. Results: The results of this study indicated that the rainfall variable (p value = 0,000, r = 0,416) and the humidity variable (p value = 0,000, r = 0,446) have a sufficient and unidirectional correlation coefficient to the incidence of DHF in Kendari City in 2012-2021, ABJ variable (p value = 0,014, r = -0,949) has a very strong and non-unidirectional correlation coefficient on the incidence of DHF in Kendari City in 2016-2020, and there is no correlation between the temperature variable (p value = 0,087) and the variable population density (p value = 0,651) with the incidence of DHF in Kendari City in 2012-2021. Conclusion: There was a correlation between rainfall and humidity variables on the incidence of DHF in Kendari City in 2012-2021, there was a correlation between the ABJ variable and the incidence of DHF in Kendari City in 2016-2020, and there wasn’t a correlation between temperature variable and population density variable on the incidence of DHF in Kendari City in 2012-2021.

Beyond eves and cracks: An interdisciplinary study of socio-spatial variation in urban malaria transmission in Ethiopia.

During the past century, the global trend of reduced malaria transmission has been concurrent with increasing urbanization. Although urbanization has traditionally been considered beneficial for vector control, the adaptation of malaria vectors to urban environments has created concerns among scientific communities and national vector control programs. Since urbanization rates in Ethiopia are among the highest in the world, the Ethiopian government developed an initiative focused on building multi-storied units organized in condominium housing. This study aimed to develop an interdisciplinary methodological approach that integrates architecture, landscape urbanism, medical anthropology, and entomology to characterize exposure to malaria vectors in this form of housing in three condominiums in Jimma Town. Mosquitoes were collected using light trap catches (LTCs) both indoor and outdoor during 2019's rainy season. Architectural drawings and ethnographic research were superposed to entomological data to detect critical interactions between uses of the space and settlement conditions potentially affecting malaria vector abundance and distribution. A total of 34 anopheline mosquitoes comprising three species (Anopheles gambiae s.l, An. pharoensis and An. coustani complex) were collected during the three months of mosquito collection. Anopheles gambiae s.l, the principal malaria vector in Ethiopia, was the predominant species of all the anophelines collected. Distribution of mosquito breeding sites across scales (household, settlement, urban landscape) is explained by environmental conditions, socio-cultural practices involving modification of existing spaces, and systemic misfits between built environment and territory. Variations in mosquito abundance and distribution in this study were mainly related to standard building practices that ignore the original logics of the territory, deficiency of water and waste disposal management systems, and adaptations of the space to fit heterogeneous lifestyles of residents. Our results indicate that contextualizing malaria control strategies in relation to vector ecology, social dynamics determining specific uses of the space, as well as building and territorial conditions could strengthen current elimination efforts. Although individual housing remains a critical unit of research for vector control interventions, this study demonstrates the importance of studying housing settlements at communal level to capture systemic interactions impacting transmission at the household level and in outdoor areas.

Human Dirofilariasis Caused by Dirofilaria repens in Sri Lanka from 1962 to 2020.

Sri Lanka has reported the highest prevalence of human dirofilariasis cases in Asia. Thus far, Dirofilaria repens is the only reported Dirofilaria species that affect humans, dogs, and cats in Sri Lanka. Therefore, this systematic review was carried out to analyse the studies performed on dirofilariasis in Sri Lanka. Peer-reviewed articles were searched on dirofilariasis published on Google Scholar, PubMed, Cochrane, and ResearchGate from January to March 2021. Articles were selected using inclusion and exclusion criteria. Three reviewers assessed the studies and extracted data independently to minimize the risk of bias. Extracted data were compiled, and then the results were compared and discussed in this systematic review. Twenty-five studies performed in Sri Lanka were analysed, and high prevalence areas, frequent clinical presentations, diagnostic methods, reservoir hosts, and treatment were identified. More than 173 cases of human dirofilariasis caused by D. repens were reported from 1962 to 2020 in 20 districts among 25 investigated. The highest number of cases (n = 80) was recorded during 2010-2012 period. Canine and feline dirofilariasis are reported countrywide, and a large number of potential mosquito breeding sites could be seen in Sri Lanka. The number of reported cases of human dirofilariasis has been varied from 1962 to 2020. The highest number of cases has reported in 2010-2012, and then the number of cases has dropped. This may be due to underreporting. Thus, awareness of Dirofilaria repens infection in humans, control measures in endemic areas and further research on dirofilariasis in other districts of Sri Lanka are crucial.

Identifying highly vulnerable mosquito breeding sites using machine learning and drone based aerial survey

This study deals with Drone based Aerial Survey in analyzing and identification of highly vulnerable mosquito breeding sites at Buckingham canal Chepauk, Chennai. It is small section of Buckingham canal studied using the drone for capturing the images and furtherly images were processed for identifying the sites prone to breeding of mosquitos. Approach used here of capturing images and classifying the vulnerable sites, using a machine learning approach in for extracting features using the algorithm and later generating a Support Vector Machine to train and classify the images. Tensorflow object detection algorithm was used to detect the object and also generate the probability level. Tensorflow based supervised classification involves stacking multiple layers of neural network for a classification. Methods like back propagation invoked in the neural networks ensures the classification accuracy are increased. In this algorithm Single shot multi box detector (SSD) has been used which provides fast detection. Single shot multi box detector (SSD) method is based on a feed-forward convolutional network, followed by a non-maximum suppression step to produce final detections. The accuracy constraint of 70% was kept for qualifying as a potential site to negate ambiguities arising due to processing errors.

Spatiotemporal distribution of malaria prevalence in the district Anuppur, central India

Background: In the current study, 2013±16 medical data were examined to evaluate intervention effects on malaria prevalence in central India. Spatiotemporal variation in the distribution of malaria types (PV, PF, and PV-PF) was also investigated and geographical distribution of malaria prevalence in central India first time.Methods: The data was collected from the primary health centers, sub health centers, community health centers, and district hospital. The data was used for the calculation of annual blood examination rate, annual parasite incidence, blood slide positive rate, blood slide falciparum rate, % PF, % PV, and % PV-PF types of malaria. The rate of malaria was transformed ( ) for carrying out statistical analyses. ANOVA models were considered for analysis of the data. The minimum deviation informatics statistic has been used to compare the spatiotemporal distribution of malaria types. The spatiotemporal distribution maps of malaria prevalence and mosquito breeding sites were generated using the geographic component software ArcGIS 10.3.Results: The results display that space was an important significant factor for malaria prevalence. Kotma, one of the blocks of the study region displayed varying geographic patterns of dominance. The analysis for the presence of malaria types indicated that space was an important source of variation for the rate of malaria due to Plasmodium falciparum. The distributional patterns of the malaria types, as observed in the empirical data were tested using the MDIS statistic and findings indicate that the distributions of malaria types for the spatial points, namely Pushparajgarh, Kotma, and Anuppur were not the same over the selected time points. The geographical maps mainly displayed the active mosquito breeding sites in river areas and handpump areas namely Karpa, Laidara, Khamraudh, Rajendragram, Sivarichndas, Basaniha, Soniyamar, Kiragi. The maps also displayed 46% high risk, 34% moderate risk, and 20% low-risk area.Conclusions: The prevalence of malaria in this tribal-dominated area shows that was governed by mosquitogenic factors and their transmission.

Acetone extracts of three selected plants induce toxicological and biological effects against the house mosquito, Culex pipiens (Diptera: Culicidae).

The biological effect of acetone extracts from three selected plants, Lantana camara, Rhazya astricta, and Citrullus colocynthis, on the egg hatch rate, larvicidal activity, and larval development of Culex pipiens L. was investigated. The egg hatch rate of Cx. pipiens was significantly reduced (P<0.01) when the extracts of L. camara were used. Moreover, the used extracts significantly exhibited a variable larvicidal activity against the Cx. pipiens (P<0.001). The most toxicity was observed when the larvae were treated with the acetonic extract of L. camara, showing different toxicities with lower LC50s at 140.1 ppm after two days and 51.3 ppm after ten days. In this observed time, larvae suffered chronic toxicities (increased mortality with increasing exposure time and sublethal endpoints, such as decreased larvae development) when treated with used plant extracts, leading to 96.7% mortality with L. camara and 91.5% and 85.7% mortalities with C. colocynthis and Rh. stricta, respectively. All concentrations significantly obstructed larvae development, causing significant reductions in both the proportion of pupation (P<0.001) and the emergence of adults (P<.001). The larval development reduction was observed under the L. camara extracts treatment, where only 15.2% and 9.7% of the larvae managed to reach pupal and adult stages, respectively. In conclusion, applying acetone extracts from L. camara to immature mosquito breeding sites may efficiently control mosquitoes to reduce the reliance on insecticides against these disease vectors.

Prevalence and Associated Factors of Malaria Infection among Outpatients Visiting Shewa Robit Health Center, Northcentral Ethiopia.

Introduction Malaria infection is a serious health problem killing millions in tropical developing countries including Ethiopia. The present study focused on assessing malaria prevalence and identification of determinants in Shewa Robit, northcentral Ethiopia. Methods A cross-sectional study was conducted among 422 participants who visited Shewa Robit Health Center between 01/10/2017 and 30/04/2018, using a simple random sampling. Sociodemographic characteristics were recorded using a pre-tested semi-structured questionnaire and infection was confirmed by microscopic examination. Data were analyzed using the Statistical Program for Social Sciences (SPSS) version 20 and p < 0.05 was used to indicate the level of significance. Results Eighty-one (19.0%) microscopically confirmed malaria cases were recorded, P.vivax was the most frequently detected species (n = 58; 71.6%). Interestingly, 73.2% (n = 309) of the participant did not utilize LLINs due to the fear of toxicity (37.4%, n = 158), misconception (21.6%, n = 91), and shortage (14.2%, n = 60). The data showed age, gender, marital status, family size, usage of LLINs and application of IRS, proximity to mosquito breeding sites and less robust and porous walls were the determinants of the infection in the study area. Conclusion The prevalence of malaria in the study population was high and P. vivax being the most common causative agent. Environmental and behavioral factors related to LLIN are the potential determinants of malaria. Continued public health interventions, targeting proper utilization of bed nets, drainage of stagnant water, and improved public awareness about reducing the risk of insect bites have the potential to minimize the infection.

Factors associated with a malaria outbreak at Tongogara refugee camp in Chipinge District, Zimbabwe, 2021: a case\u2013control study

BackgroundMalaria is a leading cause of morbidity and mortality among forcibly displaced populations, including refugees, approximately two-thirds of whom reside in malaria endemic regions. Data from the rapid disease notification system (RDNS) reports for Manicaland Province in Zimbabwe showed that despite implementation of malaria control initiatives, there was an increase in number of malaria cases above action thresholds at Tongogara refugee camp in Chipinge district during weeks 12–14 of 2021. An investigation that described the outbreak by person, place and time was conducted. Malaria emergency preparedness, response, and appropriateness of case management were assessed. The factors associated with contracting malaria were determined to enable the formulation of appropriate interventions, establish control, and prevent future malaria outbreaks among this vulnerable population.MethodsA 1:1 unmatched case–control study involving 80 cases and 80 controls was conducted using interviewer-administered questionnaires at household level. Data was entered into Epi Data version 3.1 and quantitative analysis was done using Epi Info™ version 7.2.2.6 to generate medians, proportions, odds ratios and their 95% confidence intervals.ResultsMalaria cases were distributed throughout the 10 residential sections within Tongogara refugee camp, the majority being from section 7, 28 (35%). Despite constituting 11% of the total population, Mozambican nationals accounted for 36 (45%) cases. Males constituted 47 (59%) among cases which was comparable to controls 43 (54%), p = 0.524. The median age for cases was 15 years [Interquartile range (IQR), 9–26] comparable to controls, which was 17 years (IQR, 10–30) (p = 0.755). Several natural and man-made potential vector breeding sites were observed around the camp. Risk factors associated with contracting malaria were engaging in outdoor activities at night [AOR = 2.74 (95% CI 1.04–7.22), wearing clothes that do not cover the whole body during outdoor activities [AOR 4.26 (95% CI, 1.43–12.68)], while residing in a refugee housing unit reduced the risk of contracting malaria [AOR = 0.18 (CI, 0.06–0.55)].ConclusionsThe malaria outbreak at Tongogara refugee camp reemphasizes the role of behavioural factors in malaria transmission. Intensified health education to address human behaviours that expose residents to malaria, habitat modification, and larviciding to eliminate mosquito breeding sites were recommended.

Ethnic conflict as a risk amplifier for resurgent P. vivax malaria in temperate zones: A case study from the Caucasus region

One of the most protracted post-Soviet conflicts of the 1990s was a territorial dispute between Armenia and Azerbaijan over the contested Karabakh region. Years of ethnic violence led to the displacement of nearly a million refugees, as well as a public health crisis that included epidemics of malaria, diphtheria and other preventable diseases. Malaria is not usually considered a health risk in temperate climates, but seasonal epidemics were widespread throughout the Caucasus in the early decades of the twentieth century. This paper combines qualitative historical research with geospatial analysis to explore how endemic malaria was controlled during the Soviet era, and how ethnic conflict reconfigured local ecologies to facilitate the re-emergence of P. vivax after the Soviet collapse in the 1990s. This research reveals that ethnic conflicts have specific qualities that increase risks of infectious and vector borne disease outbreaks, even in places that have successfully achieved a modern health and mortality profile. The risk amplifiers of ethnic conflicts include 1) the creation of contested spaces controlled by separatists that are outside of any national public health surveillance system; 2) mass population movements and refugee outflows due to ethnic violence; and 3) changes in land use that expand potential mosquito breeding sites throughout the conflict zone. Continued hostilities between Armenia and Azerbaijan, combined with the repopulation of key vector species (specifically An. sacharovi) lead us to conclude that populations in the Caucasus remain vulnerable to resurgent outbreaks of ethno-nationalist violence as well as the return of seasonal malaria, even after decades of successful control.

EVITA Dengue: a cluster-randomized controlled trial to EValuate the efficacy of Wolbachia-InfecTed Aedes aegypti mosquitoes in reducing the incidence of Arboviral infection in Brazil

BackgroundArboviruses transmitted by Aedes aegypti including dengue, Zika, and chikungunya are a major global health problem, with over 2.5 billion at risk for dengue alone. There are no licensed antivirals for these infections, and safe and effective vaccines are not yet widely available. Thus, prevention of arbovirus transmission by vector modification is a novel approach being pursued by multiple researchers. However, the field needs high-quality evidence derived from randomized, controlled trials upon which to base the implementation and maintenance of vector control programs. Here, we report the EVITA Dengue trial design (DMID 17-0111), which assesses the efficacy in decreasing arbovirus transmission of an innovative approach developed by the World Mosquito Program for vector modification of Aedes mosquitoes by Wolbachia pipientis.MethodsDMID 17-0111 is a cluster-randomized trial in Belo Horizonte, Brazil, with clusters defined by primary school catchment areas. Clusters (n = 58) will be randomized 1:1 to intervention (release of Wolbachia-infected Aedes aegypti mosquitoes) vs. control (no release). Standard vector control activities (i.e., insecticides and education campaigns for reduction of mosquito breeding sites) will continue as per current practice in the municipality. Participants (n = 3480, 60 per cluster) are children aged 6–11 years enrolled in the cluster-defining school and living within the cluster boundaries who will undergo annual serologic surveillance for arboviral infection. The primary objective is to compare sero-incidence of arboviral infection between arms.DiscussionDMID 17-0111 aims to determine the efficacy of Wolbachia-infected mosquito releases in reducing human infections by arboviruses transmitted by Aedes aegypti and will complement the mounting evidence for this method from large-scale field releases and ongoing trials. The trial also represents a critical step towards robustness and rigor for how vector control methods are assessed, including the simultaneous measurement and correlation of entomologic and epidemiologic outcomes. Data from this trial will inform further the development of novel vector control methods.Trial registrationClinicalTrials.govNCT04514107. Registered on 17 August 2020Primary sponsor: National Institute of Health, National Institute of Allergy and Infectious Diseases

Entomological surveillance of Stegomyia mosquitoes in and around Cochin Seaport, Kerala, India

Mosquito-borne diseases, especially Stegomyia (=Aedes) caused virus diseases are disseminating quite rapidly and is a surging global health concern. According to International Health Regulations (IHR), a minimum of 400 meter zones around seaports, airports and ground crossings are to be maintained vector free. The present vector surveillance study was carried out in and around Cochin seaport. It has been found that larval indices viz., Premise index (PI) and Breteau index (BI) were above the critical level inside the port. Also, many dry containers found in the operational areas of the seaport pose potential threat as impending breeding sites of vector mosquitoes. The larval indices noted in residential areas around the seaport were below the critical level. This necessitates utmost vigilance and necessary action from the part of concerned authorities towards protecting these sensitive territories from vector mosquitoes.

Larval density and physicochemical properties of three different breeding habitats of Anopheles mosquitoes in Sudan Savannah Region of Jigawa State, Nigeria

Mosquitoes are tiny insects that can serve as vectors for numerous infectious diseases like malaria. Malaria is considered as one of the major causes of mortality, loss of productivity and a major contributor of poverty in the African continent. In 2020, most global malaria cases (94%) were recorded in the Africa Region. In Nigeria, about 97% of the estimated populations are at risk of malaria, with up to 27% and 24% of Africa and global malaria deaths respectively in 2018. Malaria control programmes in Africa have challenge of rising insecticide resistance in the main anopheline vectors, this affects primary malaria vector control interventions. In Africa, the dominant mosquito species that transmit malaria parasites are mainly Anopheles gambiae s.s. A key control strategy against major mosquito- borne diseases involves targeting mosquito vectors to disrupt the transmission of diseases. Environmental changes can alter the genetic structure, protein profiles and enzymes of mosquitoes leading to increase in insecticide resistance. Knowing the ecology, spatial distribution of mosquito larvae, and some environmental features like physicochemical factors are important in tackling insecticide resistance. Water and larval samples were collected from three Anopheles mosquito breeding sites in August, September and October, 2019. Physicochemical parameters, larval densities and morphological specie identifications were determined. Results from this study reveal variation in levels of each studied parameter according to the site of the study. These variations can be attributed to differences in activities that occur in each site of the study.. Correlation studies indicated a significantly higher larval density in agricultural site relative to industrial and residential sites, this was by a magnitude of 10.65 and 41.30 respectively. Anopheles gambiae s.s. complex was found to be predominant in all the three study sites. These physicochemical parameters can either have negative or positive effect on mosquito biology depending on their levels, hence can affect vector control measures making it significant in terms of vector control programmes.

Recent dengue virus infection: epidemiological survey on risk factors associated with infection in a medium-sized city in Mato Grosso.

Dengue is considered to be the most important arbovirus worldwide, with important complications that increase its lethality. In Brazil, an endemic country, the disease reaches significant incidence levels, with occurrences of serious cases and high costs of hospitalizations for its treatment. To analyze risk factors among individuals with recent histories of dengue infection in a medium-sized city in Mato Grosso. Descriptive cross-sectional study, of epidemiological-survey type, conducted among the urban population of a city located in mid-northern Mato Grosso. A seroepidemiological survey using questionnaires and collection of biological material was conducted among 596 adults aged ≥ 18 years who had been selected through a cluster sampling process. Positive dengue cases were those with positive results from anti-dengue immunoassays (ELISA). Statistical analyses with descriptive and inferential techniques were used, with 95% confidence intervals and a 5% significance level. The seroepidemiological profile of the study participants was predominantly female, with ages between 18 and 39 years, self-declared non-white race/color, not more than eight years of education and not living with a companion. Among the sanitary factors analyzed, the following were risk factors for dengue virus infection: no running water at home; no water supply from the public piped network; no waste from drains or toilets sent to the sewage network; endemic disease combat agents visiting the home; and presence of mosquito breeding sites at home. Low schooling levels and previous dengue virus infection were associated with current dengue virus infection.

Automatic detection of Aedes aegypti breeding grounds based on deep networks with spatio-temporal consistency

Every year, the Aedes aegypti mosquito infects millions of people with diseases such as dengue, zika, chikungunya, and urban yellow fever. The main form to combat these diseases is to avoid mosquito reproduction by searching for and eliminating the potential mosquito breeding grounds. In this work, we introduce a comprehensive dataset of aerial videos, acquired with an unmanned aerial vehicle, containing possible mosquito breeding sites. All frames of the video dataset were manually annotated with bounding boxes identifying all objects of interest. This dataset was employed to develop an automatic detection system of such objects based on deep convolutional networks. We propose the exploitation of the temporal information contained in the videos by the incorporation, in the object detection pipeline, of a spatio-temporal consistency module that can register the detected objects, minimizing most false-positive and false-negative occurrences. Also, we experimentally show that using videos is more beneficial than only composing a mosaic using the frames. Using the ResNet-50-FPN as a backbone, we achieve F1-scores of 0.65 and 0.77 on the object-level detection of ‘tires’ and ‘water tanks’, respectively, illustrating the system capabilities to properly locate potential mosquito breeding objects.