Using UPLC–MS/MS to Evaluate the Dissemination of Pyriproxyfen by Aedes Mosquitoes to Combat Cryptic Larval Habitats after Source Reduction in Kaohsiung in Southern Taiwan

The policy regarding mosquito control strategies in Taiwan is based on integrated vector management (IVM). The major approach is source reduction via collaboration by both residents and governments. However, small and cryptic habitats of dengue vectors are hard to find and eliminate in urban communities. Therefore, this study evaluated a complementary approach that targeted cryptic habitats by utilizing mosquitoes themselves as vehicles to transfer an insect growth regulator, pyriproxyfen (PPF), to their breeding sites; the amount of PPF in breeding water was determined with ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC–MS/MS). A bioassay conducted by introducing ten late-instar larvae into PPF solution was performed to assess emergence inhibition (EI). PPF was found at 0.56 ± 0.04 ng in 25 mL of water by dissemination via ten Aedes aegypti mosquitoes exposed to 0.01% PPF, leading to 100% EI. After the community-level source reduction, a field trial in Kaohsiung in Southern Taiwan showed that 30.8–31.5% of cryptic ovitraps reached EI ≥ 50% one month after spraying 0.01% PPF in microhabitats favored by mosquitoes. IVM in parallel with residual spraying of PPF on resting surfaces of mosquitoes could serve as a simple and complementary approach to reduce cryptic larval sources in urban communities in Southern Taiwan.

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Larvicidal effect of some natural products on mosquito and some aquatic predators in Gezira State, Sudan: Field assessment

International Journal of Science and Research Archive ◽

10.30574/ijsra.2021.3.2.0134 ◽

2021 ◽

Vol 3 (2) ◽

pp. 078-082

Author(s):

Abdelmonem Eltiyab Houmida Ali ◽

Mutaman Ali A. Kehail

Keyword(s):

Natural Products ◽

Mosquito Control ◽

Mosquito Larvae ◽

Biological Control Agents ◽

Stagnant Water ◽

Source Reduction ◽

Breeding Sites ◽

Field Assessment ◽

Neem Leaves ◽

Aquatic Predators

There are many methods used for mosquito control. Depending on the situation, source reduction (removing stagnant water), bio-control (importing natural predators), trapping, and insecticides to kill larvae or adults may be used. Some aquatic predators were reputed as biological control agents for mosquito larvae. Hence they have to be considered when experimenting on the lethal effects of any material on mosquito larvae. The objectives of this study were to study the effects of neem leaves and usher latex against Anopheles and Culex larvae and some of their aquatic predators (hemipteran boatman (HB), tadpole (T), swimming beetle larvae (SBL) and adult (SBA) and mayfly naiad (MF)) in some breeding sites around Wad Medani Town. Gezira State, Sudan. Two villages were selected for conducting this study. The count of the mosquito larvae and the aquatic predators continued for four days from applying natural products. The results showed that, mosquito’s larvae were affected more than the aquatic by Neem leaves and Ushar latex. The study of the microclimates in the breeding sites will help to correlate toxicity to any level of any environmental factor.

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Identification of a Novel Brevibacillus laterosporus Strain With Insecticidal Activity Against Aedes albopictus Larvae

Frontiers in Microbiology ◽

10.3389/fmicb.2021.624014 ◽

2021 ◽

Vol 12 ◽

Author(s):

Giulia Barbieri ◽

Carolina Ferrari ◽

Stefania Mamberti ◽

Paolo Gabrieli ◽

Michele Castelli ◽

...

Keyword(s):

Aedes Albopictus ◽

Mosquito Control ◽

Control Strategies ◽

Bacterial Species ◽

16S Rrna Gene Sequencing ◽

Morphological Characterization ◽

Soil Samples ◽

Rrna Gene ◽

Breeding Sites ◽

Brevibacillus Laterosporus

Bacterial species able to produce proteins that are toxic against insects have been discovered at the beginning of the last century. However, up to date only two of them have been used as pesticides in mosquito control strategies targeting larval breeding sites: Bacillus thuringensis var. israelensis and Lysinibacillus sphaericus. Aiming to expand the arsenal of biopesticides, bacterial cultures from 44 soil samples were assayed for their ability to kill larvae of Aedes albopictus. A method to select, grow and test the larvicidal capability of spore-forming bacteria from each soil sample was developed. This allowed identifying 13 soil samples containing strains capable of killing Ae. albopictus larvae. Among the active isolates, one strain with high toxicity was identified as Brevibacillus laterosporus by 16S rRNA gene sequencing and by morphological characterization using transmission electron microscopy. The new isolate showed a larvicidal activity significantly higher than the B. laterosporus LMG 15441 reference strain. Its genome was phylogenomically characterized and compared to the available Brevibacillus genomes. Thus, the new isolate can be considered as a candidate adjuvant to biopesticides formulations that would help preventing the insurgence of resistance.

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Reducing Aedes albopictus breeding sites through education: a study in urban area

10.1101/385872 ◽

2018 ◽

Author(s):

A. Stefopoulou ◽

G. Balatsos ◽

A. Petraki ◽

Shannon L. LaDeau ◽

D. Papachristos ◽

...

Keyword(s):

Community Participation ◽

Urban Area ◽

Aedes Albopictus ◽

Resident Education ◽

Mosquito Control ◽

Educational Interventions ◽

Breeding Habitat ◽

Source Reduction ◽

Breeding Sites ◽

Attitudes And Practices

Aedes albopictus tends to proliferate in small, often man-made bodies of water, largely present in urban private areas. For this reason, education and community participation are considered crucial for source reduction and mosquito control. In the current study, we tried to relate for the first time in Greece, the effectiveness of resident education in an urban area with the number of breeding sites based on previous KAP (knowledge, attitudes and practices) studies. Our study examines the relationship between mosquito breeding sources and socioeconomic or demographic characteristics of different households in a Greek municipality and evaluates efficacy of resident education. The results revealed that only a minority of residents knew where mosquitoes breed (18.6%) and only 46% felt that residents had any responsibility for managing breeding habitat. Our findings strongly suggest that only the presence of scientific staff inspecting possible habitats in their properties, could be enough to stimulate practices towards source reduction. However, educational interventions alone with printed education material cannot enhance significant community participation and source reduction.

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SURVEILLANCE OF AEDES AEGYPTI AFTER RESURGENCE IN DOWNTOWN ST. AUGUSTINE, NORTHEASTERN FLORIDA

Journal of the Florida Mosquito Control Association ◽

10.32473/jfmca.v67i1.127631 ◽

2021 ◽

Vol 67 (1) ◽

Author(s):

Daniel Dixon

Keyword(s):

Aedes Aegypti ◽

Zika Virus ◽

Chikungunya Virus ◽

Mosquito Control ◽

Saint Augustine ◽

Mosquito Larvae ◽

Source Reduction ◽

Breeding Sites ◽

Oviposition Sites ◽

Insight Into

Aedes aegypti is an anthropophilic vector of several arboviruses, including yellow fever, Dengue virus, Chikungunya virus, and the infamous Zika virus. In 2016, Zika virus was spreading rapidly throughout Brazil and mosquito control districts expected Zika virus would be imported to Florida and vectored by endemic Aedes aegypti. Aedes aegypti often takes advantage of cryptic oviposition sites and therefore circumvents conventional control and surveillance strategies used by mosquito control practitioners. The objective of this study was to find Ae. aegypti breeding sites in the tourist district of Saint Augustine, FL, using a door-to-door on-foot approach. Mosquito control technicians, biologists and interns worked to inspect and treat each property for Ae. aegypti. Additionally, residents were informed about Ae. aegypti and its public health risk factors. In total, Anastasia Mosquito Control District inspected 1199 of the 1995 parcels in downtown Saint Augustine (60% coverage) in three months. Artificial containers were found at 1,099 of the homes inspected, and Ae. aegypti were found at 120 homes in the area. Each property where mosquito larvae and/or adults were detected was treated using source reduction, larvicides and adulticides. Residents were educated about this project and Ae. aegypti via small flyers, door hangers, pamphlets and/or verbal communication. This study provided insight into the location of Ae. aegypti breeding sites in the tourist district of Saint Augustine, FL, which will facilitate future control efforts.

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Entomological survey for identification of Aedes larval breeding sites and their distribution in Chattogram, Bangladesh

Beni-Suef University Journal of Basic and Applied Sciences ◽

10.1186/s43088-021-00122-x ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Md. Sahidur Rahman ◽

Md. Omar Faruk ◽

Sumiya Tanjila ◽

Nur Mohammad Sabbir ◽

Najmul Haider ◽

...

Keyword(s):

Logistic Regression ◽

Field Survey ◽

Mosquito Control ◽

Multiple Logistic Regression Analysis ◽

Binary Logistic Regression ◽

Breeding Sites ◽

Entomological Survey ◽

Different Types ◽

Coconut Shells ◽

Positive Properties

Abstract Background Studying the characteristics of Aedes mosquito habitats is essential to control the mosquito population. The objective of this study was to identify the breeding sites of Aedes larvae and their distribution in Chattogram, Bangladesh. We conducted an entomological survey in 12 different sub-districts (Thana) under Chattogram City, during the late monsoon (August to November) 2019. The presence of different wet containers along with their characteristics and immature mosquitoes was recorded in field survey data form. Larvae and/or pupae were collected and brought to the laboratory for identification. Results Different indices like house index, container index, and the Breteau index were estimated. The multiple logistic regression analysis was applied to identify habitats that were more likely to be positive for Aedes larvae/pupae. A total of 704 wet containers of 37 different types from 216 properties were examined, where 52 (7.39%) were positive for Aedes larvae or pupae. Tire, plastic buckets, plastic drums, and coconut shells were the most prevalent container types. The plastic group possessed the highest container productivity (50%) whereas the vehicle and machinery group was found as most efficient (1.83) in terms of immature Aedes production. Among the total positive properties, 8% were infested with Aedes aegypti, 2% with Aedes albopictus, and 1% contained both species Ae. aegypti and A. albopictus. The overall house index was 17.35%, the container index was 7%, and the Breteau index was 24.49. Containers in multistoried houses had significantly lower positivity compared to independent houses. Binary logistic regression represented that containers having shade were 6.7 times more likely to be positive than the containers without shade (p< 0.01). Conclusions These findings might assist the authorities to identify the properties, containers, and geographical areas with different degrees of risk for mosquito control interventions to prevent dengue and other Aedes-borne disease transmissions.

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Mosquito Control Priorities in Florida—Survey Results from Florida Mosquito Control Districts

Pathogens ◽

10.3390/pathogens10080947 ◽

2021 ◽

Vol 10 (8) ◽

pp. 947

Author(s):

Rishi Kondapaneni ◽

Ashley N. Malcolm ◽

Brian M. Vazquez ◽

Eric Zeng ◽

Tse-Yu Chen ◽

...

Keyword(s):

State Government ◽

Mosquito Control ◽

Control Strategies ◽

Mosquito Species ◽

Research Priorities ◽

Current Control ◽

Control Programs ◽

Common Control ◽

Surveillance Programs ◽

Research Questions

Florida lies within a subtropical region where the climate allows diverse mosquito species including invasive species to thrive year-round. As of 2021, there are currently 66 state-approved Florida Mosquito Control Districts, which are major stakeholders for Florida public universities engaged in mosquito research. Florida is one of the few states with extensive organized mosquito control programs. The Florida State Government and Florida Mosquito Control Districts have long histories of collaboration with research institutions. During fall 2020, we carried out a survey to collect baseline data on the current control priorities from Florida Mosquito Control Districts relating to (1) priority control species, (2) common adult and larval control methods, and (3) major research questions to address that will improve their control and surveillance programs. The survey data showed that a total of 17 distinct mosquito species were considered to be priority control targets, with many of these species being understudied. The most common control approaches included truck-mounted ultra-low-volume adulticiding and biopesticide-based larviciding. The districts held interest in diverse research questions, with many prioritizing studies on basic science questions to help develop evidence-based control strategies. Our data highlight the fact that mosquito control approaches and priorities differ greatly between districts and provide an important point of comparison for other regions investing in mosquito control, particularly those with similar ecological settings, and great diversity of potential mosquito vectors, such as in Florida. Our findings highlight a need for greater alignment of research priorities between mosquito control and mosquito research. In particular, we note a need to prioritize filling knowledge gaps relating to understudied mosquito species that have been implicated in arbovirus transmission.

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Risk factors associated with Ctenocephalides felis flea infestation of peri-urban goats: a neglected parasite in an under-appreciated host

Tropical Animal Health and Production ◽

10.1007/s11250-021-02620-7 ◽

2021 ◽

Vol 53 (1) ◽

Author(s):

Julia Rose Dahm ◽

Jordana Burdon Bailey ◽

Robert F. Kelly ◽

Patrick Chikungwa ◽

Julius Chulu ◽

...

Keyword(s):

Risk Factors ◽

Urban Communities ◽

Control Strategies ◽

Animal Health ◽

Animal Husbandry ◽

Ctenocephalides Felis ◽

Disease Spread ◽

Health Concern ◽

Cross Sectional ◽

Flea Infestation

AbstractGoats are critical in mixed smallholder agricultural systems in lower and middle-income countries, while fleas are important human and animal health concerns around the world. Convenience sampling was used to describe and consider risk factors for flea infestations of peri-urban goats, with the aim of informing the iterative development of animal husbandry and management based control strategies. Seven hundred and ninety-two goats were examined in 228 households across 10 peri-urban communities surrounding Blantyre in southern Malawi. The prevalence of Ctenocephalides felis fleas was 18.3, 37.1 and 100% at the levels of individual goats, households and communities, respectively, highlighting a neglected human and animal health concern. Constant introduction of new livestock coupled to a lack of biosecurity within communities, the ubiquitous presence of dog and cat hosts for C. felis, the frequency and thoroughness of cleaning overnight goat accommodation, and goat age less than 12 months old were identified as risk factors for flea infestation. This focal cross-sectional study highlights the significance of fleas in peri-urban communities and uncovers trends and commonalities that are needed to inform sustainable disease management. The majority of the peri-urban goat keepers were female, had resided in the same community throughout their whole life and had primary level education. Advice on the planned management of fleas in livestock needs to be tailored towards this demographic group. This approach affords an opportunity to promote public health measures to address household flea infestations and zoonotic disease spread.

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The distribution of Culex mosquitoes in Coimbatore, Tamil Nadu, India

Journal of Entomological and Acarological Research ◽

10.4081/jear.2015.4565 ◽

2015 ◽

Vol 47 (1) ◽

pp. 1

Author(s):

A. Naresh Kumar ◽

K. Murugan ◽

C. Thomas Vincent ◽

P. Madhiyazhagan ◽

T. Nataraj ◽

...

Keyword(s):

Tamil Nadu ◽

Mosquito Control ◽

Lymphatic Vessels ◽

Wuchereria Bancrofti ◽

Severe Damage ◽

Breeding Sites ◽

Ecological Changes ◽

Mapping System ◽

Coimbatore District ◽

Vector Distribution

Lymphatic filariasis is an infection with the filarial worms, Wuchereria bancrofti, Brugia malayi and B. timori. These parasites are transmitted to humans through the bite of an infected Culex mosquito and develop into adult worms in the lymphatic vessels, causing severe damage and swelling (lymphoedema). Mosquito control, in view of their medical as well as economical importance, assumes global importance. Geographic information system (GIS) is a powerful tool to analyse the distribution of mosquitoes and their relationship to different environmental factors, and can substantially improve our ability to quantify the impacts of demographic, climatic and ecological changes in vector distribution. In the present study Culex quinquefasciatus, Culex tritaeniorhynchus and Culex gelidus were recorded in the study area. Few other factors such as larval mosquito density, number of breeding sites, human population, etc. were also analysed for its impact on the distribution of Culex mosquitoes. Distribution of Culex in the present study affirmed that C. quinquefasciatus is predominant in the entire focal area, which explains the behavioural response and capability of the species in varied zones. Information gathered from this study is being used to construct a GIS-based mapping system for distribution of Culex mosquitoes in the Coimbatore District, Tamil Nadu, India.

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Discovery of Novel Entomopathogenic Fungi for Mosquito-Borne Disease Control

Frontiers in Fungal Biology ◽

10.3389/ffunb.2021.637234 ◽

2021 ◽

Vol 2 ◽

Author(s):

Anastasia Accoti ◽

Cecilia Springer Engdahl ◽

George Dimopoulos

Keyword(s):

Entomopathogenic Fungi ◽

Mosquito Control ◽

Control Strategies ◽

Pathogenic Fungi ◽

Suitable Alternative ◽

Control Programs ◽

Wide Range ◽

Outdoor Environments ◽

Environmentally Safe ◽

Emergence Of Resistance

The increased application of chemical control programs has led to the emergence and spread of insecticide resistance in mosquitoes. Novel environmentally safe control strategies are currently needed for the control of disease vectors. The use of entomopathogenic fungi could be a suitable alternative to chemical insecticides. Currently, Beauveria spp. and Metarhizium spp. are the most widely used entomopathogenic fungi for mosquito control, but increasing the arsenal with additional fungi is necessary to mitigate the emergence of resistance. Entomopathogenic fungi are distributed in a wide range of habitats. We have performed a comprehensive screen for candidate mosquitocidal fungi from diverse outdoor environments in Maryland and Puerto Rico. An initial screening of 22 fungi involving exposure of adult Anopheles gambiae to 2-weeks-old fungal cultures identified five potent pathogenic fungi, one of which is unidentified and the remaining four belonging to the three genera Galactomyces sp., Isaria sp. and Mucor sp. These fungi were then screened against Aedes aegypti, revealing Isaria sp. as a potent mosquito killer. The entomopathogenic effects were confirmed through spore-dipping assays. We also probed further into the killing mechanisms of these fungi and investigated whether the mosquitocidal activities were the result of potential toxic fungus-produced metabolites. Preliminary assays involving the exposure of mosquitoes to sterile filtered fungal liquid cultures showed that Galactomyces sp., Isaria sp. and the unidentified isolate 1 were the strongest producers of factors showing lethality against An. gambiae. We have identified five fungi that was pathogenic for An. gambiae and one for Ae. aegypti, among these fungi, four of them (two strains of Galactomyces sp., Mucor sp., and the unidentified isolate 1) have never previously been described as lethal to insects. Further characterization of these entomopathogenic fungi and their metabolites needs to be done to confirm their potential use in biologic control against mosquitoes.

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Mosquitoes of Etiological Concern in Kenya and Possible Control Strategies

Insects ◽

10.3390/insects10060173 ◽

2019 ◽

Vol 10 (6) ◽

pp. 173 ◽

Cited By ~ 5

Author(s):

Samuel Karungu ◽

Evans Atoni ◽

Joseph Ogalo ◽

Caroline Mwaliko ◽

Bernard Agwanda ◽

...

Keyword(s):

Environmental Changes ◽

Mosquito Control ◽

Control Strategies ◽

Mosquito Species ◽

Disease Outbreaks ◽

Health Concern ◽

Public Health Concern ◽

Vector Management ◽

Invasive Mosquito ◽

Parasitic Pathogens

Kenya is among the most affected tropical countries with pathogen transmitting Culicidae vectors. For decades, insect vectors have contributed to the emergence and distribution of viral and parasitic pathogens. Outbreaks and diseases have a great impact on a country’s economy, as resources that would otherwise be used for developmental projects are redirected to curb hospitalization cases and manage outbreaks. Infected invasive mosquito species have been shown to increasingly cross both local and global boarders due to the presence of increased environmental changes, trade, and tourism. In Kenya, there have been several mosquito-borne disease outbreaks such as the recent outbreaks along the coast of Kenya, involving chikungunya and dengue. This certainly calls for the implementation of strategies aimed at strengthening integrated vector management programs. In this review, we look at mosquitoes of public health concern in Kenya, while highlighting the pathogens they have been linked with over the years and across various regions. In addition, the major strategies that have previously been used in mosquito control and what more could be done to reduce or combat the menace caused by these hematophagous vectors are presented.

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