title: Diversity of anopheline species and their Plasmodium infection status in rural Bandarban, Bangladesh.
abstract: BACKGROUND
  Historically, the Chittagong Hill Tracts (CHT) of Bangladesh was considered hyperendemic for malaria. To better understand the contemporary malaria epidemiology and to develop new and innovative control strategies, comprehensive epidemiologic studies are ongoing in two endemic unions of Bandarban district of CHT. Within these studies entomological surveillance has been undertaken to study the role of the existing anopheline species involved in the malaria transmission cycle throughout the year.
  
  
  METHODS
  CDC miniature light traps were deployed to collect anopheline mosquitoes from the sleeping room of the selected houses each month in a single union (Kuhalong). Molecular identification was carried out for available Anopheles species complexes. Circumsporozoite proteins (CSP) for Plasmodium falciparum, Plasmodium vivax-210 (Pv-210) and Plasmodium vivax-247(Pv-247) were detected by Enzyme-linked immunosorbent assay (ELISA) from the female anopheline mosquitoes. To confirm CSP-ELISA results, polymerase chain reaction (PCR) was also performed.
  
  
  RESULTS
  A total of 2,837 anopheline mosquitoes, of which 2,576 were female, belonging to 20 species were collected from July 2009-June 2010. Anopheles jeyporiensis was the most abundant species (18.9%), followed by An. vagus (16.8%) and An. kochi (14.4%). ELISA was performed on 2,467 female mosquitoes of 19 species. 15 (0.6%) female anophelines belonging to eight species were found to be positive for Plasmodium infection by CSP-ELISA. Of those, 11 (0.4%) mosquitoes were positive for P. falciparum and four (0.2%) for Pv-210. No mosquito was found positive for Pv-247. An. maculatus (2.1%, 2/97) had the highest infection rate followed by An. umbrosus (1.7%, 2/115) and An. barbirostris (1.1%, 2/186). Other infected species were An. nigerrimus, An. nivipes, An. jeyporiensis, An. kochi, and An. vagus. Out of 11 P. falciparum CSP positive samples, seven turned out to be positive by PCR. None of the samples positive for Pv-210 was positive by PCR. In terms of abundance and incrimination, the results suggest that An. maculatus, An. jeyporiensis and An. nivipes play important roles in malaria transmission in Kuhalong.
  
  
  CONCLUSIONS
  The findings of this study suggest that even in the presence of an insecticide impregnated bed-net intervention, a number of Anopheles species still play a role in the transmission of malaria. Further investigations are required to reveal the detailed biology and insecticide resistance patterns of the vector mosquito species in endemic areas in Bangladesh in order to assist with the planning and implementation of improved malaria control strategies.
authors: International Centre for Diarrhoeal Disease Research Bangladesh (icddr,b), Dhaka, Bangladesh. shafiul@icddrb.org
authors: Mohammad Shafiul
authors: MS
authors: Alam
authors: Sumit
authors: S
authors: Chakma
authors: Wasif A
authors: WA
authors: Khan
authors: Gregory E
authors: GE
authors: Glass
authors: Abu Naser
authors: AN
authors: Mohon
authors: Rubayet
authors: R
authors: Elahi
authors: Laura C
authors: LC
authors: Norris
authors: Milka Patracia
authors: MP
authors: Podder
authors: Sabeena
authors: S
authors: Ahmed
authors: Rashidul
authors: R
authors: Haque
authors: David A
authors: DA
authors: Sack
authors: David J
authors: DJ
authors: Sullivan
authors: Douglas E
authors: DE
authors: Norris
mesh_terms: D000818:Animals; D000852:Anopheles / Q000145:classification*; D001459:Bangladesh; D003247:Conservation of Natural Resources; D017753:Ecosystem; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation; D010961:Plasmodium / Q000302:isolation & purification*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity; D013997:Time Factors
chemical_list: D015800:Protozoan Proteins; C041595:circumsporozoite protein, Protozoan