Publications

comparison of genotypes i and iii in japanese encephalitis virus reveals distinct differences in their genetic and host diversity.	japanese encephalitis (je) is an arthropod-borne disease associated with the majority of viral encephalitis cases in the asia-pacific region. the causative agent, japanese encephalitis virus (jev), has been phylogenetically divided into five genotypes. recent surveillance data indicate that genotype i (gi) is gradually replacing genotype iii (giii) as the dominant genotype. to investigate the mechanism behind the genotype shift and the potential consequences in terms of vaccine efficacy, human c ...	2014	25056890
spatio-temporal distribution of dengue and lymphatic filariasis vectors along an altitudinal transect in central nepal.	rapidly increasing temperatures in the mountain region of nepal and recent reports of dengue fever and lymphatic filariasis cases from mountainous areas of central nepal prompted us to study the spatio-temporal distribution of the vectors of these two diseases along an altitudinal transect in central nepal.	2014	25078276
multiple resistance of culex vishnui theobald against four major classes of insecticides in an agricultural area in sekinchan, selangor, malaysia.	the resistance status of riceland culex vishnui against four major groups of insecticides (i.e., organochlorines, carbamates, organophosphates and pyrethroids) was investigated. biochemical assays (estα, estβ, mfo and gst) were also conducted to detect the resistance levels. throughout a 12-month study period, multiple insecticide resistance was observed in both larvae and adult cx vishnui. culex vishnui larvae exhibited low resistance against malathion, temephos and permethrin with resistance r ...	2014	25134893
laboratory evaluation of molluscicidal & mosquito larvicidal activities of leaves of solanum nigrum l.	indiscriminate use of synthetic pesticides has created serious problem for the aquatic flora and fauna, and also resulted in appearance of pesticide resistance in vector population. this study was designed to evaluate the biocontrol efficacy of aqueous and solvent extracts of mature leaves of solanum nigrum l., against fresh water snail lymnaea acuminata f. rufescens (gray) (an intermediate host of parasites causing fasciolopsiasis) and larvae of culex vishnui group (reuben) (vector of japanese ...	0	25297363
emerging vector-borne zoonoses: eco-epidemiology and public health implications in india.	the diseases originating from animals or associated with man and animals are remerging and have resulted in considerable morbidity and mortality. the present review highlights the re-emergence of emerging mainly zoonotic diseases like chikungunya, scrub typhus, and extension of spatial distribution of cutaneous leishmaniasis from western rajasthan to himachal pradesh, kerala, and haryana states; west nile virus to assam, and non-endemic areas of japanese encephalitis (je) like maharashtra and je ...	2014	25325052
study of mosquito fauna in rice ecosystems around hanoi, northern vietnam.	species of the culex vishnui subgroup, cx. fuscocephala and cx. gelidus, which are known japanese encephalitis (je) vectors, are distributed in rice agroecosystems in asian countries. hence, although ecological studies of rice agroecosystems in northern vietnam are necessary, very few integrated studies of breeding habitats of mosquitoes, including je vectors, have been conducted. we carried out a field study and investigated the mosquito fauna in six rice production areas in northern vietnam du ...	2015	25445747
distribution of mosquito larvae in various breeding sites in national zoo malaysia.	mosquitoes are principal vectors of major vector-borne diseases. they are widely found throughout urban and rural areas in malaysia. they are responsible for various vector-borne diseases such as dengue, malaria, filariasis and encephalitis. a total of 158 mosquito larvae specimens were collected from the national zoo, malaysia, from 11 types of breeding habitats during the study period from end of may 2007 to july 2007. aedes albopictus was the predominant species (35.4%), followed by tripteroi ...	2015	25801269
morphological and molecular characterization of the ecological, biological and behavioural variants of the je vector culex tritaeniorhynchus: an assessment of its taxonomic status.	culex tritaeniorhynchus (diptera: culicidae), an important vector of japanese encephalitis belongs to the culex vishnui subgroup which includes two other vector species namely, cx. vishnui and cx. pseudovishnui. many varieties and types of cx. tritaeniorhynchus have been reported, besides populations that exhibit behavioural and biological differences. this study was undertaken to find out whether cx. tritaeniorhynchus populations exhibiting behavioural and biological variations, and those from ...	2015	25815866
remarkable repellency of ligusticum sinense (umbelliferae), a herbal alternative against laboratory populations of anopheles minimus and aedes aegypti (diptera: culicidae).	for personal protection against mosquito bites, user-friendly natural repellents, particularly from plant origin, are considered as a potential alternative to applications currently based on synthetics such as deet, the standard chemical repellent. this study was carried out in thailand to evaluate the repellency of ligusticum sinense hexane extract (lhe) against laboratory anopheles minimus and aedes aegypti, the primary vectors of malaria and dengue fever, respectively.	2015	26249666
avian plasmodium infection in field-collected mosquitoes during 2012-2013 in tarlac, philippines.	global warming threatens to increase the spread and prevalence of mosquito-transmitted diseases. certain pathogens may be carried by migratory birds and transmitted to local mosquito populations. mosquitoes were collected in the northern philippines during bird migration seasons to detect avian malaria parasites as well as for the identification of potential vector species and the estimation of infections among local mosquito populations. we used the nested pcr to detect the avian malaria specie ...	2015	26611975
evaluation of cdc light traps for mosquito surveillance in a malaria endemic area on the thai-myanmar border.	centers for disease control and prevention miniature light traps (cdc-lt) baited with co2 are a routine tool for adult mosquito sampling used in entomological surveys, and for monitoring and surveillance of disease vectors. the present study was aimed at evaluating the performance of baited and unbaited cdc-lt for indoor and outdoor trapping of endemic mosquito species in northwestern thailand.	2015	26666683
sampling design influences the observed dominance of culex tritaeniorhynchus: considerations for future studies of japanese encephalitis virus transmission.	mosquito sampling during japanese encephalitis virus (jev)-associated studies, particularly in india, has usually been conducted via aspirators or light traps to catch mosquitoes around cattle, which are dead-end hosts for jev. high numbers of culex tritaeniorhynchus, relative to other species, have often been caught during these studies. less frequently, studies have involved sampling outdoor resting mosquitoes. we aimed to compare the relative abundance of mosquito species between these two pr ...	2016	26726881
an outbreak of japanese encephalitis after two decades in odisha, india.	sudden deaths in children due to acute encephalitis syndrome (aes) from a tribal dominated district of malkangiri in odisha, india, was reported during september-november, 2012. the investigation was carried out to search for the possible viral aetiology that caused this outbreak. clinico-epidemiological survey and seromolecular investigation were carried out to confirm the viral aetiology. two hundred seventy two suspected cases with 24 deaths were observed. the patients presented with low to m ...	0	26905239
japanese encephalitis: challenges and intervention opportunities in nepal.	japanese encephalitis (je) is a mosquito borne zoonotic disease caused by je virus (jev). je has been endemic in terai region, the lowland plains of nepal bordering india, since 1978. however, in recent years cases of je has been continuously reported from high altitude zones of hills and mountains. irrigated rice farming system, expanded pig husbandry practices, inadequate vaccine coverage, low level of public awareness and climate change favoring mosquito breeding in higher altitudes might be ...	2015	27046998
the spatio-temporal distribution of japanese encephalitis cases in different age groups in mainland china, 2004 - 2014.	japanese encephalitis (je) is very prevalent in china, but the incidence of je among children has been greatly reduced by extensive promotion of vaccinations. the incidence of je among adults, however, has increased in some parts of china.	2016	27050414
development of a pcr methodology to distinguish species members of culex vishnui subgroup (diptera: culicidae), based on dna barcodes.		2017	27060606
assessment of angelica sinensis (oliv.) diels as a repellent for personal protection against mosquitoes under laboratory and field conditions in northern thailand.	angelica sinensis (oliv.) hexane extract (ahe) has been reported as a proven and impressive repellent against laboratory-reared female aedes aegypti mosquitoes. with the aim of promoting products of plant origin as a viable alternative to conventional synthetic substances, this study was designed to transform ahe-based repellents for exploitable commercial production by enhancing their efficacy and assessing their physical and biological stability as well as repellency against mosquitoes under l ...	2016	27357395
japanese encephalitis : is routine immunization required?	japanese encephalitis is the leading cause of viral encephalitis in asia. in endemic areas annual incidence ranges from 10-100 per 100000 population. case fatality averages 30% and a high percentage of the survivors are left with permanent neuropshychiatric sequelae. there is no effective drug treatment for this disease. in recent decades, japanese encephalitis virus has caused epidemics in previously unaffected countries like india, myanmar, nepal, sri lanka, thailand and viet nam. no effective ...	2011	27407808
vertical stratification of adult mosquitoes (diptera: culicidae) within a tropical rainforest in sabah, malaysia.	malaria cases caused by plasmodium knowlesi, a simian parasite naturally found in long-tailed and pig-tailed macaques, are increasing rapidly in sabah, malaysia. one hypothesis is that this increase is associated with changes in land use. a study was carried out to identify the anopheline vectors present in different forest types and to observe the human landing behaviour of mosquitoes.	2016	27430261
a tropical menace of co-infection of japanese encephalitis and neurocysticercosis in two children.	japanese encephalitis (je) is a mosquito borne encephalitis caused by flavivirus. neurocysticercosis (ncc) is a parasitic disease of the central nervous system caused by taenia solium. in this report, we describe the clinical profile, imaging findings, and outcome of two children with je and coexisting ncc. eleven and thirteen-year-old boys from the same town of jharkhand state were brought with history of fever, seizures, altered sensorium, and extrapyramidal symptoms. dystonia, hypomimia, brad ...	0	27606026
intensive circulation of japanese encephalitis virus in peri-urban sentinel pigs near phnom penh, cambodia.	despite the increased use of vaccination in several asian countries, japanese encephalitis (je) remains the most important cause of viral encephalitis in asia in humans with an estimated 68,000 cases annually. considered a rural disease occurring mainly in paddy-field dominated landscapes where pigs are amplifying hosts, je may nevertheless circulate in a wider range of environment given the diversity of its potential hosts and vectors. the main objective of this study was to assess the intensit ...	2016	27926937
detection of west nile virus in six mosquito species in synchrony with seroconversion among sentinel chickens in india.	west nile virus (wnv) is a zoonotic flavivirus maintained in mosquito-bird transmission cycle. although humans are accidental hosts, fatal outcomes following wnv infection have been reported from india. studies have identified wnv as an important etiological agent causing acute encephalitis syndrome in assam, northeast india. while circulation of wnv is evident, the role of vectors and avian hosts involved in the transmission remains unclear. in this study we identified local mosquito species fo ...	2017	28061903
how zoophilic japanese encephalitis vector mosquitoes feed on humans.	japanese encephalitis virus (jev) is the most frequent cause of mosquito-borne encephalitis in asian countries. several culicine species are potential vectors. the primary jev vectors feed mainly on cows (a dead-end host for jev), pigs (an amplifying host), and, occasionally, humans (a dead-end host). it is essential to determine blood-feeding patterns to understand the transmission cycle of the disease. here we review blood-feeding characteristics of the primary jev vectors culex tritaeniorhync ...	2017	28082626
commensal viruses of mosquitoes: host restriction, transmission, and interaction with arboviral pathogens.	recent advances in virus detection strategies and deep sequencing technologies have enabled the identification of a multitude of new viruses that persistently infect mosquitoes but do not infect vertebrates. these are usually referred to as insect-specific viruses (isvs). these novel viruses have generated considerable interest in their modes of transmission, persistence in mosquito populations, the mechanisms that restrict their host range to mosquitoes, and their interactions with pathogens tr ...	2017	28096646
larvicidal activity of phytosteroid compounds from leaf extract of solanum nigrum against culex vishnui group and anopheles subpictus.	vector control is facing a menace due to the appearance of resistance to synthetic insecticides. insecticides of plant origin may provide appropriate substitute biocontrol techniques in the future. the present study was carried out to investigate the bio control potentiality of active ingredient isolated from chloroform: methanol (1:1 v/v) extract of mature leaves of solanum nigrum l. (solanaceae) against early 3rd instar larvae of culex vishnui group (comprising of cx. vishnui theobald, cx. pse ...	2017	28330500
identifying sources, pathways and risk drivers in ecosystems of japanese encephalitis in an epidemic-prone north indian district.	japanese encephalitis (je) has caused repeated outbreaks in endemic pockets of india. this study was conducted in kushinagar, a highly endemic district, to understand the human-animal-ecosystem interactions, and the drivers that influence disease transmission. utilizing the ecosystems approach, a cross-sectional, descriptive study, employing mixed methods design was employed. four villages (two with pig-rearing and two without) were randomly selected from a high, a medium and a low burden (based ...	2017	28463989
diversity of mosquitoes (diptera: culicidae) attracted to human subjects in rubber plantations, secondary forests, and villages in luang prabang province, northern lao pdr.	the impact of the rapid expansion of rubber plantations in south-east asia on mosquito populations is uncertain. we compared the abundance and diversity of adult mosquitoes using human-baited traps in four typical rural habitats in northern lao pdr: secondary forests, immature rubber plantations, mature rubber plantations, and villages. generalized estimating equations were used to explore differences in mosquito abundance between habitats, and simpson's diversity index was used to measure speci ...	2017	28505314
molecular typing and phylogeny of wolbachia: a study from assam, north-eastern part of india.	wolbachia are maternally inherited endosymbiotic alphaproteobacteria, infecting 40-75% of arthropod species. knowledge on distribution of native strains infecting mosquito vectors from endemic regions is essential for successful implementation of vector control interventions utilizing potential strains of wolbachia. study identified various native strains of wolbachia inhabiting different mosquito species from field and colonised conditions of assam. the fly drosophila melanogaster was also incl ...	2017	28939497
incidence of dengue and chikungunya viruses in mosquitoes and human patients in border provinces of vietnam.	dengue virus remains a major threat in vietnam, while chikungunya virus is expected to become one. surveillance was conducted from 2012 to 2014 in vietnam to assess the presence of dengue and chikungunya viruses in patients hospitalized with acute fever in five vietnam provinces neighboring lao pdr and cambodia. surveillance was extended to mosquitoes present in the vicinity of the patients' households.	2017	29121985
evaluation of mosquito larvicidal activity of fruit extracts of acacia auriculiformis against the japanese encephalitis vector culex vishnui.	the larvicidal potentiality of crude and ethyl acetate extracts of fruits of acacia auriculiformis was investigated against all the larval instars of je vector culex vishnui. the crude extracts showed good results against all the larval instars with highest mortality at 0.09%. highest mortality was found at 300 ppm of ethyl acetate extract. lowest lc50 value was obtained at 72 h for third instar larvae. non target organisms tested, showed no to very less mortality to ethyl acetate solvent extrac ...	2019	29457745
dna barcoding of five japanese encephalitis mosquito vectors (culex fuscocephala, culex gelidus, culex tritaeniorhynchus, culex pseudovishnui and culex vishnui).	culex mosquitoes can act as vectors of several important diseases, including japanese encephalitis, west nile virus, st. louis encephalitis and equine encephalitis. besides the neurological sequelae caused in humans, japanese encephalitis can lead to abortion in sows and encephalitis in horses. effective vector control and early diagnosis, along with continuous serosurveillance in animals, are crucial to fight this arboviral disease. however, the success of vector control operations is linked wi ...	2018	29625090
entomological investigation of japanese encephalitis outbreak in malkangiri district of odisha state, india.	a severe outbreak of japanese encephalitis (je) and acute encephalitis syndrome (aes) with high case fatality was reported from malkangiri district of odisha state, india during september to november 2016 affecting 336 children with 103 deaths.	2018	29768623
microfilaria persistent foci during post mda and the risk assessment of resurgence in india.	pondicherry, a union territory in india, is an endemic district for bancroftian lymphatic filariasis transmitted by culex quinquefasciatus where eight rounds of mass drug administration (mda) were completed in 2011 (annually once from 2004 to 2011).the objectives of this study were to conduct a focal survey to assess microfilaria and antigen (ag) prevalence among young adults and to assess vector infection and infectivity through a focal entomological survey.	2018	30026669
a comparative study of mosquito and sand fly (diptera: psychodidae: phlebotominae) sampling using dry ice and chemically generated carbon dioxide from three different prototype co2 generators.	a comparative study was conducted to test the efficiency of centers for disease control and prevention (cdc) light traps baited with either dry ice or carbon dioxide (co2) produced from one of three different sources in collecting mosquitoes (diptera: culicidae) in thailand. treatments consisted of dry ice pellets, co2 gas produced from one of three prototype co2 generator systems (tda, cube, moustiq-air med-e-cell - mec), and a cdc light trap without a co2 source. the best performing prototype ...	2019	30321387
larvivorous potentiality of puntius tetrazona and hyphessobrycon rosaceus against culex vishnui subgroup in laboratory and field based bioassay.	this study assessed the predatory potentiality of two unexplored fishes, puntius tetrazona and hyphessobrycon rosaceus on culex vishnui subgroup larvae in order to utilize natural resources to diminish mosquito population. larval feeding rate was evaluated in laboratory under varying prey density and volume of water. the experiment was extended to semi field condition.	2018	30409146
insecticide resistance status of three vectors of japanese encephalitis in east central india.	japanese encephalitis (je) has been reported in different districts of odisha state (east central india) since 1992. during 2016, a major outbreak of je and acute encephalitis syndrome (aes) occurred in the malkangiri district of odisha, causing 103 deaths in children, of which 37 were caused by je and 66 by aes. information on insecticide resistance in je vectors is important for the selection of appropriate insecticides for use in vector control. the present study was designed to determine the ...	2019	30565276
changing paradigm in the epidemiology of japanese encephalitis in a non-endemic region.	japanese encephalitis (je) is a mosquito-borne zoonotic disease. the je virus (jev) does not cause any disease among its natural hosts and transmission continues through mosquitoes belonging to culex vishnui subgroup. this study was aimed to investigate the prevalence of jev in mosquitoes and humans in the thanjavur district, a non-endemic region for je, in tamil nadu, by using standard available assays.	2019	30618446
entomological factors in relation to the occurrence of japanese encephalitis in malkangiri district, odisha state, india.	japanese encephalitis is a mosquito-borne arbo-viral disease with seasonal occurrence. since 2009, aes/je cases have been reported from malkangiri district of odisha state, india at an interval of one year.in the current study, the entomological parameters of known je vector mosquito species were assessed for one year in malkangiri district. mosquito collections were done fortnightly in the index villages from august 2015 to july 2016 to record the density, their breeding habitats, feeding behav ...	2019	31544624