title: Assessment of laboratory and field assays of sunlight-induced killing of mosquito larvae by photosensitizers.
abstract: The effectiveness of light-induced killing of mosquito larvae in the presence of photosensitizers was studied with larvae of Aedes aegypti (L.), Anopheles stephensi (Liston), and Culex quinquefasciatus Say grown in the laboratory and of Cx. quinquefasciatus grown under field conditions. Tested photosensitizers included xanthene, chlorin, and porphyrin derivatives. All the larvae were treated at the fourth instar. Preliminary laboratory experiments showed a light-induced lethal effect of Rose Bengal (RB) on three species of mosquito larvae. Compared with other photosensitizers, RB seemed to be more efficient at even lower concentration than chlorin (e6) and chlorophyllin on Ae. aegypti larvae. Among the four porphyrin derivatives, i.e., chloroquinoline tetraphenyl propioamidoporphine, tetraphenyl porphine tetrasulfonate, hematoporphyrin (HP), and tetraphenylporphinepropionic acid porphine, HP was the only effective photosensitizer on Ae. aegypti larvae. The best conditions for field tests using RB were conducted on Cx. quinquefasciatus in Bobo-Dioulasso, Burkina Faso. The mortality induced by RB varied from 80 to 96% obtained with unfiltered cesspit water to 0.4 to 6.7% in cesspits with a heavy load of organic materials, thus providing the basis for further developments of this technique under field conditions.
authors.affiliation: Faculty of Sciences, University of Ngaoundéré, P.O. Box 454 Ngaoundéré, Cameroon.
authors.forename: Blaise
authors.initials: B
authors.lastname: Dondji
authors.forename: Stephane
authors.initials: S
authors.lastname: Duchon
authors.forename: Abdoulaye
authors.initials: A
authors.lastname: Diabate
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Herve
authors.forename: Vincent
authors.initials: V
authors.lastname: Corbel
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Hougard
authors.forename: Rene
authors.initials: R
authors.lastname: Santus
authors.forename: Joseph
authors.initials: J
authors.lastname: Schrevel
mesh_terms: D000330:Aedes; D000818:Animals; D000852:Anopheles; D003465:Culex; D009033:Culicidae; D007306:Insecticides; D007814:Larva; D017319:Photosensitizing Agents; D012395:Rose Bengal; D013472:Sunlight
chemical_list: D007306:Insecticides; D017319:Photosensitizing Agents; D012395:Rose Bengal