Journal of Biological Engineering Research and Review, 2016; 3(2): 01-07 ISSN: 2349-3232 Online Available online at www.biologicalengineering.in/Archive Research Article Prevalence of An. culicifacies sibling species and vector incrimination of Anopheles mosquitoes in Magway and Bago Region of Myanmar Maung Maung Mya1*, Phyo Wai Win2, Aye Mya Thanda2, Thi Ha1, Maung Maung Gyi2, Myin Zu Min2 1Medical Entomology Research Division, Department of Medical Research, Ministry of Health and Sport, Myanmar 2Department of Zoology, Yangon University, Myanmar *Email: [email protected] ARTICLE INFO: Article History: Abstract: The present study was conducted in Thayetchaung village (Bowbin dam area) of Received: 01/07/2016 Ghobinkauk Township, Bago Region and Maybinthar village, Myothit Township Magway Region Revised: 02/08/2016 to determine the present of individual vector species and the prevalence of sibling species Accepted: 16/08/2016 Anopheles culicifacies from December 2013 to November 2014. Adult Anopheline mosquitoes Available Online: 01/09/2016 were collected by different collection methods according to WHO guideline. Christopher stage ovaries were collected from An. culicifacies for ovarian nurse cell chromosome study and head Keywords: and thorax were dissected for vector incrimination study. During the study periods, a total of Malaria, 1727 and 507 female Anopheles comprising 11 and 10 species were collected from Thayetchaung Anopheles culicifacies, and Maybinthar villages respectively. An. vagus(576) was the predominant species followed by monoclonal antibodies, An. annularis(430) >An. philippnensis(238) >An.maculatus (164) > and An. culicifacies(150) in Bowbin village, Thayetchaung. In Maybinthar, highest density of An. culicifacies(237) were collected, followed by Christopher stage ovary, An.annularis(60)>An.maculatus(42). The main vector An.minimuswas observed 31 in Bowbin and 24 in Maybinthar. Man biting rate of An.minimus was found 1.25, 1.25 indoor and 1.5, 1.00 outdoor bite/man/night and for An.culicifacies was found 1.25, 1.25 indoor and 3.00, 5.25 outdoor bite/man/night in Thayetchaung and Maybinthar respectively. An.cilicifacies B was present in both study villages and species A, C, D and E were absent. Species B was predominantly higher in the study village of Myothit Township (61.24%) than Thayetchaung village Ghobinkauk Township (38.76%). Vector incrimination study found that only 1 well of pool samples ofAn.minimuswas found 3.226% (1/31) of Pv247sporozoite positive in Thayetchaung village. An.minimus was a potential vector of malaria. None of the specimens belonging to An. culicifacies B was found with circumsporozoite antigen of any of the Plasmodium species in both areas. Therefore An. culicifacies is not important vector of malaria, An. dirus and An. minimus are the major vectors of malaria in Myanmar. INTRODUCTION An.stiphensi and An.culicifacies are secondary or suspected vectors of malaria in Myanmar [3]. The Anopheles mosquitoes breeding sites are very greatly depending on the climatic alaria remains a major health problem in Myanmar. M conditions and availability of water. In Myanmar An.minimus According to Ministry of Health (MOH) malaria has been a and An.dirus are considered to be one of the most efficient priority public health problem in Myanmar. According to malaria vectors due to their ability to adapt so rapidly. Health in Myanmar 2014, morbidity and mortality rate were Previously An.minimus was found foothill and forest fringe 24.35/1000 population and 12.62/100000 population but now it is found in rice field in plain areas. Anopheles dirus respectively in 1990 and 6.44/1000population and 0.48/ species are also bred in deep forest areas but now their larvae 1000,000 populations respectively in 2013 [1]. Plasmodium were found in men made wells in Mon State and Thanintheryi falciparum is the predominant species but now P. vivax is Region [4, 5] because certain environmental changes like gradually rising in Myanmar [2]. These parasites are deforestation and vegetation clearance for crop plantations transmitted by Anopheles mosquitoes. Although more than 37 and also rapid growth of population and installation of new Anopheles mosquitos’ species are exist in Myanmar, only few rural areas may lead to an increase abundance of mosquito species are involved in the transmission of malaria. An.dirus larval habitats [6, 7]. Well breeding An.dirus from Mon State and An.minimus are the main vectors of malaria but was cyto-taxonomically identified as sibling species D [8]. A An.maculatus, An.vagus, An.annularis, An.philippnensis, recent study of cyto-taxonomic identification in Anopheline 1 mosquitoes in Kamamaung Township Kayin State revealed species may have its own distribution and biology. Large that An.minimus A, An.dirus D and An.culicifacies B sibling number of sibling species B of An.culicifacies adult and larvae species were present in this area [9]. were found in hyper-endemic foothill areas of Paukkaung Township, Bago Region in Myanmar [20, 21]. Main vectors of An.dirus and An.minimusare larking in some malaria endemic areas in Myanmar where the suspected vectors as An. culicifacies, An. maculatus and An.annularisare presented abundantly [12]. Vector incrimination is a prerequisite for understanding the role of Anopheline in malaria transmission and has been used to determine which species is the most important vector [22-24]. It also is used to compare the contribution of individual species to overall malaria transmission [25]. Very few literatures were available about sibling species of Anopheles in Myanmar. Therefore the present study was undertaken in Bawbin dam area of BagoYoma forest fringe area and Maypinthar village of plain area in Magway Regions to fine out the An.culicifacies sibling species prevalence and potential vector of malaria. MATERIALS AND METHODS Study areas and study period: (1) Entomological survey was conducted in Thayetchaung village (Bawbin dam area), Ghobinkauk Township Bago Figure 1: Thayetchaung village, Bowbin dam areas Division (2) Maypinthar village Myothit Township Magway Region seasonally from December 2013 to November 2014 Anopheles maculatus are main vector of malaria in Malaysia (Fig. 1). [10] but it is a secondary vector of malaria in Myanmar and widely distributed in hilly and plain areas of Southeast Asia Thayetchaung village(Bowbin dam area)Ghobinkauk including Myanmar. About 30 Anopheles taxa have been Township Bago Division identified so far as species complexes they are important Thayetchaung village (Bowbin dam area)is situated beside vectors of malaria in different parts of the World. Members of the Bowbin dam. It is 15 kilometer away from Pyiy – a species complex, commonly known as sibling Paukkaung road. The population is about 1000. Almost all of species/isomorphic or cryptic species, are reproductively the households have one to two mosquito nets which are used isolated evolutionary units with distinct gene pools and for the prevention of mosquitoes bite. hence, differ in biological characteristics which determine their potential in the transmission of diseases. .Anopheles Maypinthar village Myothit Township Magway Region culicifacies species complex are widespread distribution in Maypyinthar village, Myothit Township Magway Region was Asia, from Iran, Afghanistan and Pakistan in west and India to selected for the collection of Anopheles mosquitoes and larvae. Bangladesh, Myanmar and Thailand in the east. It is also found Maypinthar village is situated beside the MagwayNaypyidaw in Nepal and Southern China in the North and Sri Lanka in road. The village is 10 kilometer away from Son dam. South [11]. Anopheles culicifacies is a fresh water breeder and MaypintharMyothit car road is across the village. The found three sibling species A, B, and D were recorded in population is about 2000. Ninety percent of the households Myanmar [12, 8] and India [13] but in Sri Lanka An.culicifacies have one to two mosquito nets. sibling species E is breeding in brackish waters [14]. Anopheles culicifacies is a complex of 5 sibling species Adult mosquito’s collection designated as species A, B, C, D and E. Species B is not the Adult mosquitoes were collected by WHO sucking tube with vector but all other species transmit malaria, although their several mosquitoes catching methods using cattle baited big vectorial capacity varies greatly [15]. It is the vector of rural net trap (330x330x180cm) collection, indoor and outdoor and peri-urban malaria in the peninsular India [13]. Species A human bait mosquito collection and indoor morning resting and D are efficient malaria vectors, whereas species B is mosquito in both areas seasonally at 18:00 to 01:00 hours for regarded as a poor vector of malaria in India [16]. In Sri Lanka, 5 days. however, species B has long been considered to be an important malaria vector. Anopheles culicifaciesof A-E have Larvae collection been detected in Sri Lanka with species Ebeing incriminated Anopheles Larvae were collected in and around 3-kilometer as the major malaria vector of P. falciparum and P. vivax [17, radius from the study villages. Water pools, sand pools, 18]. Anopheles culicifacies is the secondary vector of malaria footprints, rock pools and slowly running water in river band and widely distribution in Myanmar [12, 19]. Each sibling were detected. 2 Identification of Mosquitoes sporozoite antigen in salivary glands. All collected samples Wild caught adult mosquitoes and adult mosquitoes emerged were store in a freezer at - 4ºC. This procedure reduced the from pupae collection during larva surveys were identified by probability of detection of CS antigen from other parts of the morphologically identification method using adult Anopheles body [33]. Head and thorax of individual vectors were coded mosquito identification keys of different authors. [19, 26-29]. identically for correlating the results, Ovary collection and processing Vector incrimination Blood fed An.culicifacies were separate out by the help of Head and thorax of individual Anopheles species and sucking tube to paper cup with glucose for ovary An.culicifacies specimens identified at sibling species level by development.