EVALUATION OF THE EFFICACY OF 3-PERCENT CITRONELLA CANDLES AND 5-PERCENT CITRONELLA INCENSE FOR PROTECTION AGAINST FIELD POPULATIONS OF AEDES MOSQUITOS

We assessed the efficacy of 3% citronella candles and 5% citronella in cense in protecting subjects from bites of Aedes spp. under field cond itions. The study was conducted in a deciduous woodlot in Guelph, Onta rio, Canada from July 26 to August 10, 1995. Eight subjects, dressed i dentically, were assigned to one of 8 positions on a grid within the s tudy area. Two citronella candles, 2 citronella incense, 2 plain unsce nted candles, or no candles (i.e., nontreated controls) were assigned to 2 positions on the grid each evening. Subjects conducted 5-min biti ng counts at each position and performed 16 biting counts per evening. On average, subjects received 6.2 +/- 0.4, 8.2 +/- 0.5, 8.2 +/- 0.4, and 10.8 +/- 0.5 bites/ 5 min at positions with citronella candles, ci tronella incense, plain candles, and no candles, respectively. Althoug h significantly fewer bites were received by subjects at positions wit h citronella candles and incense than at nontreated locations, the ove rall reduction in bites provided by the citronella candles and incense was only 42.3 and 24.2%, respectively.