title: Short report: failure to select for chloroquine- or mefloquine-resistant Plasmodium berghei through drug pressure in Anopheles stephensi mosquitoes.
abstract: We investigated whether chloroquine- or mefloquine-resistant Plasmodium berghei could be selected through drug pressure applied during continuous cyclical transmission in Anopheles stephensi mosquitoes. Mosquitoes were infected by feeding them on mice previously inoculated with a drug-sensitive clone of P. berghei ANKA. Mosquitoes ingested mefloquine or chloroquine with the infectious blood-meal, or by feeding on a drug-treated (uninfected) mouse 4 or 10 days after the infectious blood-meal. Twenty-two days after being infected, mosquitoes transmitted sporozoites to uninfected mice. Blood from these animals was used to infect naive mice that were then used to reinitiate the mouse/mosquito/mouse cycle. A total of 20 passages through mosquitoes were completed while under drug pressure. Drug-resistance levels were assessed in the initial clone and after 20 passages through mosquitoes. None of 18 "sub-clones" of parasites showed significant increases in chloroquine or mefloquine resistance, suggesting that exposure of sporogonic stage Plasmodium to chloroquine or mefloquine will not result in the development of drug resistance.
authors.affiliation: Department of Entomology, United States Army Medical Component-Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: R E
authors.initials: RE
authors.lastname: Coleman
authors.forename: G H
authors.initials: GH
authors.lastname: Song
authors.forename: R A
authors.initials: RA
authors.lastname: Wirtz
mesh_terms: D000818:Animals; D000852:Anopheles / Q000469:parasitology*; D000962:Antimalarials / Q000494:pharmacology*; D002738:Chloroquine / Q000494:pharmacology*; D004351:Drug Resistance; D007303:Insect Vectors / Q000469:parasitology*; D008288:Malaria / Q000469:parasitology; D015767:Mefloquine / Q000494:pharmacology*; D051379:Mice; D018512:Parasitemia / Q000097:blood; D010962:Plasmodium berghei / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000962:Antimalarials; D002738:Chloroquine; D015767:Mefloquine