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Fulltext The Plasmodium falciparum male gametocyte protein P230p, a paralog of P230, is vital for ookinete formation and mosquito transmission

Marin-Mogollon C, van de Vegte-Bolmer M, van Gemert GJ, van Pul FJA, Ramesar J, Othman AS, et al.

Sci Rep, 2018 10 08;8(1):14902.
PMID: 30297725 DOI: 10.1038/s41598-018-33236-x

Two members of 6-cysteine (6-cys) protein family, P48/45 and P230, are important for gamete fertility in rodent and human malaria parasites and are leading transmission blocking vaccine antigens. Rodent and human parasites encode a paralog of P230, called P230p. While P230 is expressed in male and female parasites, P230p is expressed only in male gametocytes and gametes. In rodent malaria parasites this protein is dispensable throughout the complete life-cycle; however, its function in P. falciparum is unknown. Using CRISPR/Cas9 methodology we disrupted the gene encoding Pfp230p resulting in P. falciparum mutants (PfΔp230p) lacking P230p expression. The PfΔp230p mutants produced normal numbers of male and female gametocytes, which retained expression of P48/45 and P230. Upon activation male PfΔp230p gametocytes undergo exflagellation and form male gametes. However, male gametes are unable to attach to red blood cells resulting in the absence of characteristic exflagellation centres in vitro. In the absence of P230p, zygote formation as well as oocyst and sporozoite development were strongly reduced (>98%) in mosquitoes. These observations demonstrate that P230p, like P230 and P48/45, has a vital role in P. falciparum male fertility and zygote formation and warrants further investigation as a potential transmission blocking vaccine candidate.

Matched MeSH terms: Culicidae/growth & development; Culicidae/parasitology*
Fulltext Larvicidal and anti-termite activities of microbial biosurfactant produced by Enterobacter cloacae SJ2 isolated from marine sponge Clathria sp

Harikrishnan S, Sudarshan S, Sivasubramani K, Nandini MS, Narenkumar J, Ramachandran V, et al.

Sci Rep, 2023 Sep 13;13(1):15153.
PMID: 37704703 DOI: 10.1038/s41598-023-42475-6

The widespread use of synthetic pesticides has resulted in a number of issues, including a rise in insecticide-resistant organisms, environmental degradation, and a hazard to human health. As a result, new microbial derived insecticides that are safe for human health and the environment are urgently needed. In this study, rhamnolipid biosurfactants produced from Enterobacter cloacae SJ2 was used to evaluate the toxicity towards mosquito larvae (Culex quinquefasciatus) and termites (Odontotermes obesus). Results showed dose dependent mortality rate was observed between the treatments. The 48 h LC50 (median lethal concentration) values of the biosurfactant were determined for termite and mosquito larvae following the non-linear regression curve fit method. Results showed larvicidal activity and anti-termite activity of biosurfactants with 48 h LC50 value (95% confidence interval) of 26.49 mg/L (25.40 to 27.57) and 33.43 mg/L (31.09 to 35.68), respectively. According to a histopathological investigation, the biosurfactant treatment caused substantial tissue damage in cellular organelles of larvae and termites. The findings of this study suggest that the microbial biosurfactant produced by E. cloacae SJ2 is an excellent and potentially effective agent for controlling Cx. quinquefasciatus and O. obesus.

Matched MeSH terms: Culicidae*
First Report of Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelidae) as a museum insect pest in Malaysia

Heo CC, Hidayatulfathi Othman, Nazni Wasi Ahmad, Heah SK, Lee HL, Jeffery J, et al.

Sains Malaysiana, 2010;39:315-320.

This paper reports the infestation of psocid, Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelidae) in the insect museum at Medical Entomology Unit, Institute for Medical Research, Kuala Lumpur. These tiny organisms were recognised as museum insect pest and found frequently in the insect boxes containing mosquitoes, flies, cockroaches and butterflies. They feed on dead insect specimens and cause severe physical damages to the valuable reference specimens collected in the early 20th century. Hence, it is important to control their population immediately to prevent them from causing further deterioration to the museum collection.

Matched MeSH terms: Culicidae
Feature selection algorithms for Malaysian dengue outbreak detection model

Husam IS, Abuhamad, Azuraliza Abu Bakar, Suhaila Zainudin, Mazrura Sahani, Zainudin Mohd Ali

Sains Malaysiana, 2017;46:255-265.

Dengue fever is considered as one of the most common mosquito borne diseases worldwide. Dengue outbreak detection can be very useful in terms of practical efforts to overcome the rapid spread of the disease by providing the knowledge to predict the next outbreak occurrence. Many studies have been conducted to model and predict dengue outbreak using different data mining techniques. This research aimed to identify the best features that lead to better predictive accuracy of dengue outbreaks using three different feature selection algorithms; particle swarm optimization (PSO), genetic algorithm (GA) and rank search (RS). Based on the selected features, three predictive modeling techniques (J48, DTNB and Naive Bayes) were applied for dengue outbreak detection. The dataset used in this research was obtained from the Public Health Department, Seremban, Negeri Sembilan, Malaysia. The experimental results showed that the predictive accuracy was improved by applying feature selection process before the predictive modeling process. The study also showed the set of features to represent dengue outbreak detection for Malaysian health agencies.

Matched MeSH terms: Culicidae
Dengue vector control in malaysia: a review for current and alternative strategies

Ong SQ

Sains Malaysiana, 2016;45:777-785.

Dengue is a major issue in Malaysia as the dramatic emerge of infection. Yet an effective vaccine or medicine is not
yet available, although many attempts are undergoing. Dengue vector control is still considered the most effective way
for controlling and preventing the transmission of dengue virus. Nonetheless, as the conventional approaches are less
successful in managing the dengue transmission, it is time to review the current applied and other available approaches.
Current dengue vector relied greatly on the chemical approach as space treatment either thermal or ULV fogging, however,
the approach seem like under the expectation. Beside space treatment, new control methods for example biological
control (bacterium Bacillus thuringiensis, predatory mosquito Toxorhynchites) and attractive trap were carried out
at certain location of Malaysia. Moreover, new emerged approaches such as mass release of genetic modification or
artificially Wolbachia infected male dengue vector for the objective of generating sterile offspring when mate with
wild population is urge to be tested in Malaysia, although concerns have to be taken before the actual mass release. In
conclusion, control of dengue vector shall not consist exclusively for a single approach, neither genetic modification
of artificially Wolbachia infected technique, nor the conventional insecticidal treatment. It should, however, comprise
of the environment management as the fundamental approach, a well-planned integrated control program and a good
cooperation among the organization.

Matched MeSH terms: Culicidae
Fulltext Intricate predatory decisions by a mosquito-specialist spider from Malaysia

Jackson RR, Li D, Woon JR, Hashim R, Cross FR

R Soc Open Sci, 2014 Oct;1(2):140131.
PMID: 26064534 DOI: 10.1098/rsos.140131

Paracyrba wanlessi is a southeast Asian jumping spider (Salticidae) that lives in the hollow internodes of fallen bamboo and preys on the larvae, pupae and adults of mosquitoes. In contrast to Evarcha culicivora, an East African salticid that is also known for actively targeting mosquitoes as preferred prey, there was no evidence of P. wanlessi choosing mosquitoes on the basis of species, sex or diet. However, our findings show that P. wanlessi chooses mosquitoes significantly more often than a variety of other prey types, regardless of whether the prey are in or away from water, and regardless of whether the mosquitoes are adults or juveniles. Moreover, a preference for mosquito larvae, pupae and adults is expressed regardless of whether test spiders are maintained on a diet of terrestrial or aquatic prey and regardless of whether the diet includes or excludes mosquitoes. Congruence of an environmental factor (in water versus away from water) with prey type (aquatic versus terrestrial mosquitoes) appeared to be important and yet, even when the prey were in the incongruent environment, P. wanlessi continued to choose mosquitoes more often than other prey.

Matched MeSH terms: Culicidae
Direct nucleotide sequencing using total cellular RNA from dengue-virus-infected mosquito cells

Kautner IM, Lam SK

Res. Virol., 1992 May-Jun;143(3):193-7.
PMID: 1355609

In recent years, a large amount of nucleotide sequence data for dengue viruses has been published. Most of it was derived by sequencing cDNA synthesized from highly purified genomic viral RNA. This paper presents a simple and rapid method for the isolation of total RNA from mosquito cells infected with dengue viruses. This RNA can be used for direct nucleotide sequencing with specific primers without the need for further purification.

Matched MeSH terms: Culicidae/cytology; Culicidae/genetics*
Clostridium bifermentans serovar malaysia: sporulation, biogenesis of inclusion bodies and larvicidal effect on mosquito

Charles JF, Nicolas L, Sebald M, de Barjac H

Res. Microbiol., 1990 7 1;141(6):721-33.
PMID: 1980958

Sporulation of Clostridium bifermentans serovar malaysia, which has a larvicidal activity towards mosquitoes, was examined by electron microscopy. Parasporal inclusion bodies lacking a crystalline structure were first detected at t5 (5 h after the end of exponentional growth). Also, the presence of "brush-bottle"-like appendages appearing first at t5 was noted; these remained attached to the spores when released after sporangium lysis. Larvicidal activity assayed on Anopheles stephensi larvae appeared at t0 and increased rapidly to a maximum between t5 and t8. However, a decrease in bacterial toxicity occurred with sporangium lysis.

Matched MeSH terms: Culicidae
Fulltext Dengue virus type 2 envelope protein displayed as recombinant phage attachment protein reveals potential cell binding sites

Abd-Jamil J, Cheah CY, AbuBakar S

Protein Eng. Des. Sel., 2008 Oct;21(10):605-11.
PMID: 18669522 DOI: 10.1093/protein/gzn041

A method to map the specific site on dengue virus envelope protein (E) that interacts with cells and a neutralizing antibody is developed using serially truncated dengue virus type 2 (DENV-2) E displayed on M13 phages as recombinant E-g3p fusion proteins. Recombinant phages displaying the truncated E consisting of amino acids 297-423 (EB2) and amino acids 379-423 (EB4) were neutralized by DENV-2 patient sera and the DENV-2 E-specific 3H5-1 monoclonal antibodies suggesting that the phages retained the DENV-2 E antigenic properties. The EB4 followed by EB2 recombinant phages bound the most to human monocytes (THP-1), African green monkey kidney (Vero) cells, mosquito (C6/36) cells, ScFv specific against E and C6/36 cell proteins. Two potential cell attachment sites were mapped to loop I (amino acids 297 to 312) and loop II (amino acids 379-385) of the DENV-2 E using the phage-displayed truncated DENV-2 E fragments and by the analysis of the E structure. Loop II was present only in EB4 recombinant phages. There was no competition for binding to C6/36 cell proteins between EB2 and EB4 phages. Loop I and loop II are similar to the sub-complex specific and type-specific neutralizing monoclonal antibody binding sites, respectively. Hence, it is proposed that binding and entry of DENV involves the interaction of loop I to cell surface glycosaminoglycan-motif and a subsequent highly specific interaction involving loop II with other cell proteins. The phage displayed truncated DENV-2 E is a powerful and useful method for the direct determination of DENV-2 E cell binding sites.

Matched MeSH terms: Culicidae/immunology; Culicidae/metabolism
Fulltext Fungal infection in an infantry battalion in Malaya

Harris GF

Proc R Soc Med, 1962 Jul;55:562-3.
PMID: 13904834
Matched MeSH terms: Culicidae*
Fulltext Clinical aspect of leptospirosis in Malaya

Trimble AP

Proc R Soc Med, 1957 Feb;50(2):125-8.
PMID: 13408224
Matched MeSH terms: Culicidae*
Fulltext Leptospirosis among troops operating in Malaya during 1954 and 1955

Levis DG

Proc R Soc Med, 1957 Feb;50(2):119-24.
PMID: 13408223
Matched MeSH terms: Culicidae*
Host preferences of mosquitoes

Tempelis CH

Proc Pap Annu Conf Calif Mosq Control Assoc, 1970;38:25-8.
PMID: 4395205
Matched MeSH terms: Culicidae*
Fulltext Genotypic and phenotypic characterization of Chikungunya virus of different genotypes from Malaysia

Sam IC, Loong SK, Michael JC, Chua CL, Wan Sulaiman WY, Vythilingam I, et al.

PLoS One, 2012;7(11):e50476.
PMID: 23209750 DOI: 10.1371/journal.pone.0050476

Mosquito-borne Chikungunya virus (CHIKV) has recently re-emerged globally. The epidemic East/Central/South African (ECSA) strains have spread for the first time to Asia, which previously only had endemic Asian strains. In Malaysia, the ECSA strain caused an extensive nationwide outbreak in 2008, while the Asian strains only caused limited outbreaks prior to this. To gain insight into these observed epidemiological differences, we compared genotypic and phenotypic characteristics of CHIKV of Asian and ECSA genotypes isolated in Malaysia.

Matched MeSH terms: Culicidae/virology
Fulltext Factors affecting dengue prevention practices: nationwide survey of the Malaysian public

Wong LP, Shakir SM, Atefi N, AbuBakar S

PLoS One, 2015;10(4):e0122890.
PMID: 25836366 DOI: 10.1371/journal.pone.0122890

Efforts to stamp dengue in many dengue endemic countries has met little success. There is a need to re-examine and understand how the public at large view the dengue prevention efforts. This study aimed to examine the demographic factors, theoretical constructs of the Health Belief Model and knowledge about dengue and how these influence the practice of dengue prevention.

Matched MeSH terms: Culicidae/physiology
Factors associated with mosquito control among construction workers: A systematic review

Dapari R, Mohd Fadzil MF, Hanzir MY, Mohamed Jais JS, Safarudin NF, Albar A

PLoS One, 2024;19(5):e0303330.
PMID: 38718075 DOI: 10.1371/journal.pone.0303330

INTRODUCTION: Workers in the construction industry frequently work in construction sites with numerous areas that can potentially accumulate water, such as tanks, wet cement surfaces, or water puddles. These water collection sites become ideal breeding grounds for mosquito infestation, which leads to a higher prevalence of mosquito-borne diseases, especially malaria and dengue among construction workers. Despite that numerous factors have been identified in controlling vector-borne diseases, the specific factors that influence mosquito control at construction sites have yet to be explored.
AIMS: This systematic review aims to determine the factors associated with mosquito control among construction workers.
METHODS: Primarily, articles related to factors associated with mosquito control among construction workers were collected from two different online databases (ScienceDirect and EBSCOhost). Two independent reviewers were assigned to screen the titles and abstracts of the collected data, stored in Microsoft Excel, against the inclusion and exclusion criteria. Afterwards, the quality of the included articles was critically assessed using the Mixed Method Appraisal Tool (MMAT). Of the 171 articles identified, 4 were included in the final review.
RESULTS: Based on the thorough evaluation, mosquito-related knowledge, practical mosquito prevention measures, and Larval Source Management (LSM) were identified as vital factors associated with mosquito control among construction workers. The significant association between mosquito-related knowledge and control practices indicates higher knowledge linked to effective practices, particularly among female workers and those who were recently infected with malaria. Concurrently, there were notable challenges regarding sustainable preventive measures and larval control methods in construction settings.
CONCLUSION: Implementing effective mosquito control, including knowledge and practice on mosquito control together with vector control, is highly required to suppress the expanding mosquito population. It is recommended that employers provide continuous mosquito control education and training to their employees and reward them with incentives, while employees should comply with the guidelines set by their employers to ensure successful mosquito control and reduce the spread of mosquito-borne diseases in the construction industry.

Matched MeSH terms: Culicidae/physiology
Some observations and experiments on Malayan Anopheles with special reference to the transmission of malaria. I. Experimental and natural infection of insects with malaria with some notes on the morphology and biology of certain type of Anopheles rossi

Barber M

Philippine Journal of Science, 1918;8.

Matched MeSH terms: Culicidae
Fulltext Persistent mosquito fogging can be detrimental to non-target invertebrates in an urban tropical forest

Lee NSM, Clements GR, Ting ASY, Wong ZH, Yek SH

PeerJ, 2020;8:e10033.
PMID: 33062440 DOI: 10.7717/peerj.10033

Background: Human population growth has led to biodiversity declines in tropical cities. While habitat loss and fragmentation have been the main drivers of urban biodiversity loss, man-made interventions to reduce health risks have also emerged as an unintentional threat. For instance, insecticide fogging to control mosquito populations has become the most common method of preventing the expansion of mosquito-borne diseases such as Dengue. However, the effectiveness of fogging in killing mosquitoes has been called into question. One concern is the unintended effect of insecticide fogging on non-target invertebrates that are crucial for the maintenance of urban ecosystems. Here, we investigate the impacts of fogging on: (1) target invertebrate taxon (Diptera, including mosquitoes); (2) non-target invertebrate taxa; and (3) the foraging behavior of an invertebrate pollinator taxon (Lepidoptera) within an urban tropical forest.
Methods: We carried out fogging with Pyrethroid insecticide (Detral 2.5 EC) at 10 different sites in a forest situated in the state of Selangor, Peninsular Malaysia. Across the sites, we counted the numbers of knocked-down invertebrates and identified them based on morphology to different taxa. We constructed Bayesian hierarchical Poisson regression models to investigate the effects of fogging on: (1) a target invertebrate taxon (Diptera) 3-h post-fogging; (2) selected non-target invertebrate taxa 3-h post-fogging; and (3) an invertebrate pollinator taxon (Lepidoptera) 24-h post-fogging.
Results: A total of 1,874 invertebrates from 19 invertebrate orders were knocked down by the fogging treatment across the 10 sites. Furthermore, 72.7% of the invertebrates counted 3-h post-fogging was considered dead. Our regression models showed that given the data and prior information, the probability that fogging had a negative effect on invertebrate taxa 3-h post-fogging was 100%, with reductions to 11% of the pre-fogging count of live individuals for the target invertebrate taxon (Diptera), and between 5% and 58% of the pre-fogging count of live individuals for non-target invertebrate taxa. For the invertebrate pollinator, the probability that fogging had a negative effect 24-h post-fogging was also 100%, with reductions to 53% of the pre-fogging count of live individuals.
Discussion: Our Bayesian models unequivocally demonstrate that fogging has detrimental effects on one pollinator order and non-target invertebrate orders, especially taxa that have comparatively lower levels of chitinisation. While fogging is effective in killing the target order (Diptera), no mosquitos were found dead in our experiment. In order to maintain urban biodiversity, we recommend that health authorities and the private sector move away from persistent insecticide fogging and to explore alternative measures to control adult mosquito populations.

Matched MeSH terms: Culicidae
Fulltext Evaluation of female Aedes aegypti proteome via LC-ESI-MS/MS using two protein extraction methods

Shettima A, Ishak IH, Abdul Rais SH, Abu Hasan H, Othman N

PeerJ, 2021;9:e10863.
PMID: 33717682 DOI: 10.7717/peerj.10863

Background: Proteomic analyses have broadened the horizons of vector control measures by identifying proteins associated with different biological and physiological processes and give further insight into the mosquitoes' biology, mechanism of insecticide resistance and pathogens-mosquitoes interaction. Female Ae. aegypti ingests human blood to acquire the requisite nutrients to make eggs. During blood ingestion, female mosquitoes transmit different pathogens. Therefore, this study aimed to determine the best protein extraction method for mass spectrometry analysis which will allow a better proteome profiling for female mosquitoes.
Methods: In this present study, two protein extractions methods were performed to analyze female Ae. aegyti proteome, via TCA acetone precipitation extraction method and a commercial protein extraction reagent CytoBusterTM. Then, protein identification was performed by LC-ESI-MS/MS and followed by functional protein annotation analysis.
Results: The CytoBusterTM reagent gave the highest protein yield with a mean of 475.90 µg compared to TCA acetone precipitation extraction showed 283.15 µg mean of protein. LC-ESI-MS/MS identified 1,290 and 890 proteins from the CytoBusterTM reagent and TCA acetone precipitation, respectively. When comparing the protein class categories in both methods, there were three additional categories for proteins identified using CytoBusterTM reagent. The proteins were related to scaffold/adaptor protein (PC00226), protein binding activity modulator (PC00095) and intercellular signal molecule (PC00207). In conclusion, the CytoBusterTM protein extraction reagent showed a better performance for the extraction of proteins in term of the protein yield, proteome coverage and extraction speed.

Matched MeSH terms: Culicidae
Fulltext Identification of potential vectors of Dirofilaria immitis and Brugia pahangi (Spirurida: Filariidae): First observation of infective third-stage larva of B. pahangi in Culex quinquefasciatus (Diptera: Culicidae)

Vinnie-Siow WY, Low VL, Tan TK, Wong ML, Leong CS, Ahmad NW, et al.

Pathog Glob Health, 2022 Sep;116(6):356-364.
PMID: 35287548 DOI: 10.1080/20477724.2022.2035624

Information on the mosquito species that transmit canine filariosis is scanty. Hence, an experimental study was conducted to identify the potential vectors responsible for the transmission of D. immitis Leidy and B. pahangi Buckley & Edeson. A total of 367 mosquitoes belonging to six species containing both laboratory and field strains (i.e. Aedes togoi Theobald, Aedes aegypti Linnaeus, Aedes albopictus Skuse, Culex quinquefasciatus Say, Culex vishnui Theobald and Anopheles dirus Peyton & Harrison) were used in this study. All mosquitoes were artificially fed on either D. immitis or B. pahangi microfilariae (mfs) infected blood by using the Hemotek™ membrane feeding system. Out of 367 mosquitoes, 228 (64.9%) were fully engorged. After feeding on D. immitis (20%) and B. pahangi (33%) mfs positive blood, the mortality rates for Cx. quinquefasciatus were found to be slightly lower than that of other species of mosquitoes. On the other hand, majority of An. dirus were found to be incapable to withstand the infection of mfs as the mortality rates were relatively high (D. immitis = 71.4%; B. pahangi = 100.0%). Brugia pahangi was detected in Ae. togoi and Cx. quinquefasciatus with infection rates of 50% and 25%, respectively. Aedes togoi was the only species infected with D. immitis with an infection rate of 69%. Our results showed that Ae. togoi was an excellent experimental vector for both D. immitis and B. pahangi. This study also documented the observation of B. pahangi, for the first time in the head region of Cx. quinquefasciatus under a laboratory setting.

Matched MeSH terms: Culicidae*

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