We studied on the blood feeding pattern of Anopheles mosquitoes in malaria endemic area of Bangladesh.Anopheles mosquitoes were collected by means of light trap (LT), pyrethrum spray (PS) and human bait (HB) from a malaria endemic village in the eastern Bangladesh in 2010. A total of 2456 female anopheline mosquitoes representing 21 species were collected from the study area. All species were collected by LT set indoor (n=1094), 19 species were from outdoor (n=784), whereas, 6 by PS (n=549) and 4 species by HB (n=29). We demonstrated that An. baimai,An.minimus s.l, An.annularis, An.jamesii,An.maculatus s.l. and An.pallidus are more or less anthropophilic, while most of the other species are zoophilic. Collected mosquitoes species composition were methodology-specific, light trap sampling can be taken as neutral reflecting the real fauna, while human bait catch comprise of only anthropophilic species, indoor spray catch comprise of only endophylic species. In preliminary survey to incriminate malaria vectors applying proper sampling method is indispensable in Bangladesh.

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Dengue virus is the causative agent of fatal disease, which has no vaccine available. Breakage of transmission is still the core of prevention. The prospects of innovating new prevention techniques include genetically modified dengue-resistant transgenic mosquitoes. That innovation begins with a search of mosquito genes that are affected by dengue infection. Using RNA-seq technique by Illumina Genome Analyzer, we have previously analyzed and compared whole transcriptome of 14-day dengue-infected and non-infected Aedes aegypti. At present, we analyzed and compared 6- and 14-day dengue-infected Ae.aegypti. Approximately 70 millions and 60 millions short reads were obtained from 6- and 14-day dengue infected mosquitoes, respectively. They were mapped onto 14,653 and 14,275 genes. Among them, a total of 11 and 14 genes were up- and down-regulated more than 7.39 folds, respectively. We will report the genes that are found to be significantly affected by the interaction between Ae.aegypti and dengue virus.

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The insects of the subfamily Triatominae (Hemiptera, Reduviidae) are vectors of Trypanosoma cruzi, agent of Chagas disease, endemic in Latin America, but not recorded in the rest of the world. The increasing migration flows open the possibility for a spreading of T.cruzi in non-endemic countries. Autochtonous species of triatomine bugs are recorded in South-East Asia but data on their actual distribution and behaviour as a possible vector and/or pest are considerably lacking. Very outdated records of three species are the only available informations regarding the triatomine bugs in the Philippines. In order to confirm the alleged presence of the bug there, a preliminary field trip of one month was undertaken between December 2011 and January 2012. In Quezon City (the biggest municipality in Metro Manila) and in the outskirts of Tarlac City (Tarlac province), the local population was inquired about their awareness of the presence of the bug. A general knowledge both of the existence and the behaviour of the triatomine bugs was found, especially among the humble people; if inquired, they also frequently reported of big painful swellings on the skin after episodes of bites. Reportedly, the insect is mainly found inside the habitations and during nighttime. Through those connections was possible to collect a few specimen in Quezon City, all identified as Triatoma rubrofasciata. Quezon City is a highly urbanized area and the specimen were collected in the slums; old and sometimes miserable dwellings were the collection sites. This collection represents the first record of T.rubrofasciata in the Philippines since the '40s. According to this preliminary survey the triatomine bugs are likely to be widely distributed all over the country and frequently involved in episodes of human blood feeding.

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Two new species of black flies, Simulium(Simulium) sp. 1 and S.(S.) sp.2, are described on the basis of adult, pupal and larval specimens collected from Tioman Island, Pahang, Malaysia, and are placed in the tuberosum species-group within the subgenus Simulium(Simulium) Latreille. Both S.(S.)sp. 1 and S. (S.) sp. 2, are characterized by one of the two unusual characteristics within the species-group, i.e., the female tarsal claw with a minute subbasal projection, and the pupal thoracic integument with a pit-like organ near the base of each gill. Simulium(S.) sp. 2 is also striking in having a dichoptic male head, a characteristic rarely recorded in the family Simuliidae. The speciation of both new species on Tioman Island in two lines of the tuberosum species-group is inferred.

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In recent surveys of pupae and larvae of black flies in Peninsular Malaysia, two new species of black flies, Simulium sp.1 and S.sp.2, were collected. Both species are placed in the batoense species-group within the subgenus Gomphostilbia, which is one of two dominant subgenera of the genus Simulium in Peninsular Malaysia as well as in the Oriental Region. Strikingly,three morphological characteristics which rarely occur in the subgenus Gomphostilbia are found in these two new species: the very narrow female frons and the mushroom-like pupal terminal hooks in S.sp. 1 and the pupal gill composed of an inflated horn-like structure and eight slender filaments in S.sp.2.

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To understand the possibility of the spreading of vector borne diseases, the study on host preference of the vector mosquitoes is an important epidemiological tool. In Japan, although there is no report of the outbreak of West Nile fever so far, the most potential vector species of the virus prevalent here is Culex pipiens pallens, which is closely related to the Cx.pipiens of USA.In the present study,Cx.p.pallens were collected from Tsunami stricken areas of Miyagi prefecture in 2011, after the earthquake disaster and blood meal analysis was performed using the primers for cytochrome b gene and 16S ribosomal RNA regions of the mitochondrial DNA and compared with the previous data studied during 2004 to 2007. The study revealed that 92.1% mosquitoes were fed on avian blood while only 7.9% were fed on mammalian blood. But the result of the study of 2004 to 2007 showed that 50% Cx.p. pallens were positive for Avian blood and 38.6% were positive for mammalian blood where about 11.4% mosquitoes were fed on both avian and mammalian hosts. Although Cx.p.pallens has preference for avian hosts, a good number of mosquitoes showed affinity to human as well as other mammalian hosts. After the disaster, since the population in tsunami affected areas gets limited, a reflection in the change of feeding pattern of this species was observed, indicating that the species is highly opportunistic regarding its host preference.

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The effect of incineration on corpse may affect the oviposition activities of blowflies and colonisation of maggots on the corpse, resulting in variations on decomposition rate. The present study was conducted to observe the effect of incineration on the PMI and insect succession on a badly incinerated monkey carcasses in a forested area in Gombak, Selangor, Malaysia. The decomposition process of carcasses gone through 4 stages, namely fresh (2 days), decay (1—2 days), advanced decay (1 day) and remains (11—20days). No bloating stage was observed because the abdominal cavity was exposed after incineration process. The fauna succession pattern was similar in both incinerated and non-incinerated carcasses with the succession sequence of firstly Calliphoridae, Sarcophagidae and lastly Muscidae, indicating incineration effect did not affect the pattern of fauna succession. The decomposition rate of incinerated carcasses was faster compared to non-incinerated carcasses and the incineration effect did not deter the arrival and oviposition of flies. Therefore, PMI estimation on incinerated carcass by using insect evidence was not affected by incineration effect.

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Re-emergence of dengue fever is a public health concern in Japan. As insecticides are the major tool for vector control, it is important to monitor susceptibility of the vector to insecticides. However,little is known about the present insecticide resistance status of A. albopictus in Japan. Kawada et al (2010;JJID 63:19-24) reported that larvae of some populations of A. albopictus in Nagasaki City had strong resistance to d-allethrin. Later we found that resistance to permethrin in the adult stage was limited in some of these populations, and high resistance to DDT in the adult stage was common in all the populations tested. It is yet to be clear how Nagasaki populations have developed resistance to pyrethroids and whether it is related to the resistance to DDT. We aimed to investigate the resistance to pyrethroids and DDT in A.albopictus population from several places in Japan to compare with Nagasaki populations. These include strains originated from several cities and populations from southern islands,Amami and Yonaguni. High DDT resistance was found in all samples except the Yonaguni population. Permethrin resistance was detected in a half of the sites. It is likely that the DDT resistance developed by extensive use of this chemical in the past still remains in A.albopictus populations widely in Japan. However DDT resistance may not be the cause of the pyrethroid resistance that was observed sporadically from different places.

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Aedes aegypti is one of the most common urban tropical mosquito species and an important vector of dengue, chikungunya, and yellow fever viruses. It is also an organism with a complex life history where larval stages are aquatic and adults are terrestrial. This ontogenetic niche shift could shape the density-dependent regulation of this and other mosquito species, because events that occur during the larval stages impact adult densities. Herein, we present results from simple density-dependent mathematical models fitted using maximum likelihood methods to weekly time series data from Puerto Rico and Thailand. Density-dependent regulation was strong in both populations. Analysis of climatic forcing indicated that populations were more sensitive to climatic variables with low kurtosis, i.e., climatic factors highly variable around the median, rainfall in Puerto Rico, and temperature in Thailand. Changes in environmental variability appear to drive sharp changes in the abundance of mosquitoes. The identification of density-independent (i.e., exogenous) variables forcing sharp changes in disease vector populations using the exogenous factors statistical properties, such as kurtosis, could be useful to assess the impacts of changing climate patterns on the transmission of vector-borne diseases.

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Locating breeding sites is important for mitigating actions to control malaria vectors. However,an extensive survey for malaria vector habitats at large geographical scale is not cost effective. Modelling of vector breeding sites is useful for vector control, especially where labour, time and fund are main constraint. Given that topographic features affect the spatial distribution of water pools, they could be used for modelling the distribution of vector breeding habitats. Here, we evaluated the predictive performance of Shuttle Radar Topography Mission version3 (SRTM3,90m), Advanced Spaceborne Thermal Emission Reflection Radiometer Global DEM (ASTER,90m) and Advanced Land Observing Satellite (ALOS, 90m). Using GIS, topographic variables were extracted from the Digital Elevation Models (DEMs). We used the data of breeding sites from an extensive field survey conducted on an island of western Kenya in 2006. The topographic variables were extracted for 826 breeding sites,and 4520 negative pointes were randomly assigned. Logistic regression model was applied to characterize topographic features of the malaria vector breeding sites and predict their locations. Model accuracy was evaluated using the area under Receiver Operating Characteristics curve (AUC). We observed that topographic derivatives from the three DEMs showed significant correlation with breeding habitats except for aspect. The AUCs results from the training data set revealed highest model accuracy for SRTM (0.758), followed by ASTER (0.756) and ALOS the least (0.748).Findings from model validation in an independent area showed similar order of model strength revealed in the training data set. SRTM again, outperformed other DEMs (AUC 0.829),closely followed by ASTER (AUC,0.818) and ALOS (AUC,0.69).Although these satellite sensors had different levels of modelling accuracies,they were accurate enough to predict vector habitats.

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