Mosquito species diversity and abundance in relation to riceland agroecosystem and filarial infection in Kafr El-Sheikh Governorate, Egypt.

Abstract

The present work studied the mosquitoes abundance, identification, distribution and density in three villages (rural area) and one city (urban area) in Kafr El-SheikhGovernorate namely; Kebreet, Minyat Al-Ashraaf, El-Salmia and Fowa city, respectively during the rice cultivation season in relation to filaria from June to Oct. 2009. A total of 11381 mosquitoes larvae belonging to four genera and 8 species were collected. Of which 3525 (31.0%) in Minyat Al-Ashraaf followed by 3339 (29.3%) in Kebreet, 3331 (29.3%) in El-Salmia villages compared with 1186 (10.4%) in Fowa city. The five most common species collected during this study were Culex pipiens (39.2%), Cx. antennatus (27.3%), Cx. univittatus (15.8%), Anopheles pharoensis (10.4%), and An. coustani (3.8%). The mosquito species diversity (H) and evenness (EH) in the (rice cultivated areas) Minyat Al-Ashraf, Kebreet and El-Salmia villages (H = 1.286, EH = 0.829; H = 1.227, EH = 0.742; H = 1.110, EH = 0.882; respectively) were much higher than in the Fowa city (non rice cultivated area) (H = 0.718, EH = 0.608). On the other hand, the highest diversity and density of adult mosquitoes species obtained from Minyat Al-Ashraaf were 5 species and (33.8%), followed by Kebreet 5 species and (31.6%), El-Salmia 4 species and (24.5%), respectively compared with 3 species and (10.1%) in Fowa city. C. pipiens adults were the predominant species, in all filarial indicator areas (68.1, 53.4, 40.8 and 20.8 mosquitoes/room) in Minyat Al-Ashraaf, Kebreet, El-Salmia villages and Fowa city, respectively. Cx. pipiens was the only species to carry infective larvae as well as other stages, while Cx. antennatus carried immature stages only (not infective). Filarial larvae in Cx. pipiens and Cx. antennatus were found only in Minyat Al-Ashraaf and Kebreet villages. It is inferred from the data that different levels of habitat with regard to rice cultivation have different effects on mosquito diversity and abundance. Also, our study revealed that filarial vectors Cx. pipiens and Cx. antennatus had a wide distribution and high relative density especially in irrigated rice regions and hence its role in disease transmission in Kafr El-Sheikh region needs further investigation .