Identification of wild collected mosquito vectors of diseases using gas chromatography–mass spectrometry in Jazan Province, Saudi Arabia

Abstract

Thirty-three species of mosquitoes have been reported from the Kingdom of Saudi Arabia. Several of these mosquitoes, Anopheles gambiae Giles s.l., Anopheles stephensi Liston, Culex pipiens Linnaeus, Culex quinquefasciatus Say, Culex tritaeniorhynchus Giles, Stegomyia aegypti (Linnaeus) and Aedimorphus vexans arabiensis (Patton) are known vectors of human and animal diseases. In this study, the cuticular hydrocarbon profiles of eight mosquito species using gas chromatography-mass spectrometry were analyzed. Wild collected fourth-instar larvae were reared, and single, newly emerged, unfed adult females were used for the analysis. A total of 146-160 peaks were detected from the cuticular extracts by gas chromatography. Repeated analysis of variance (ANOVA) and Tukey HSD Post Hoc test was used to test for quantitative differences in relative hydrocarbon quantity. In addition, a linear regression model was applied using Enter method to determine the diagnostic peaks for the eight mosquito specimens. The ANOVA test indicated that relative peaks were significant (P < 0.05) when selected pairs of peaks were compared. Also, seven compounds showed qualitative differences among the five mosquito vectors tested. The classes of constituents present were n-alkanes, monomethylalkanes, dimethylalkanes, trimethylalkanes, alkenes, branched aromatic hydrocarbons, aldehydes and esters. These compounds have a carbon chain length ranging from 8 to 18 carbons. The most abundant compound in all adult mosquito specimens was n-hexylacrylate [retention time (RT) 6.73 min], which was not detected in Cx. pipiens. In Cx. pipiens, the most abundant peak was benzaldehyde (RT 2.98 min). Gas chromatography-mass spectrometry is a suitable method to identify adult mosquitoes, especially from focal areas of public health concern such as Jazan Province, Saudi Arabia. This method allows a wide range of adult collected material to be identified with high accuracy.

Modeling the distribution of the West Nile and Rift Valley Fever vector Culex pipiens in arid and semi-arid regions of the Middle East and North Africa

“…Likewise, the region of highest probability of occupancy in Saudi Arabia corresponds with recent collections of Cx. pipiens [62-64] and the incidence of infection during the 2000 Rift Valley Fever virus outbreak [65]. The distribution of suitable Cx.…”

Assessment and an updated list of the mosquitoes of Saudi Arabia

“…Records: [2] (as Ae. arabiensis ); [6, 16] (as Aedimorphus v. arabiensis ), [17–23] (as Aedimorphus arabiensis ); [24, 25]; [26] (as Ae. vexans ).…”

Mosquito vectors survey reveals new record of Culiseta subochrea in Al-Ahsa Oasis, Saudi Arabia

“…pipiens is encountered in the majority of surveys conducted in Saudi Arabia. It has been recorded inthe eastern region [16][17][18][19][20], western region [26,27], southwestern region [24,25,28,29] and the middle region [30] of Saudi Arabia. In agreement with the present findings, it is commonly found in sites with low and/or moderate salinity [19].…”

“…longiareolata was encountered in one location only, ArRumaylah, in a few numbers (total number of larvae = 39) during February to April 2010 and representing the sixth mosquito species collected in the present work. Out of 26 studies, some studies [16,18,20,[24][25][26][28][29][30] mentioned the prevalence of this species in different places in Saudi Arabia but in variable percentages. It was the second commonest mosquito species collected from Asir province [24].…”