The response of Culex quinquefasciatus (Diptera : Culicidae) to traps baited with carbon dioxide, 1-octen-3-ol, acetone, butyric acid and human foot odour in Tanzania

The responses of Culex quinquefasciatus Say to traps baited with carbon dio xide, 1-octen-3-ol, acetone, butyric acid and human foot odour were studied in the field in Muheza, north-east Tanzania using Counterflow Geometry (CF G) and Centers for Disease Control (CDC) traps. It was found that significa ntly more C. quinquefasciatus responded to foot odour collected on nylon st ockings than to clean nylon stockings (P < 0.05). Significantly more mosqui toes were caught in a CFG trap baited with carbon dioxide than in traps wit h either human foot odour, acetone or butyric acid. It was also found that in an outdoor situation a carbon dioxide baited CDC unlit trap collected ov er 12 times more C. quinquefasciatus than an unbaited CDC unlit trap and ni ne times more mosquitoes than CDC traps baited with 1-octen-3-ol alone (P < 0.05). The number of mosquitoes caught in a CDC trap baited with 1-octen-3 -ol did not differ significantly from that of the unbaited CDC trap (P > 0. 05). These results indicate that the Afrotropical C. quinquefasciatus respo nd significantly better to traps baited with carbon dioxide than to either octenol, acetone or butyric acid, and that human foot odour contains stimul i to which C. quinquefasciatus is attracted under field conditions.