title: Midgut bacteria in Anopheles gambiae and An. funestus (Diptera: Culicidae) from Kenya and Mali.
abstract: Field studies in Kenya and Mali investigated the prevalence of bacteria in the midguts of malaria vectors, and the potential relationship between gram-negative bacteria species and Plasmodium falciparum sporozoites. Midguts were dissected from 2,430 mosquitoes: 863 Anopheles funestus Giles and 1,037 An. gambiae s.l. Giles from Kenya, and 530 An. gambiae s.l. from Mali. An. funestus had a higher prevalence of gram-negative bacteria (28.5%) compared with An. gambiae collected in Kenya and Mali (15.4 and 12.5%, respectively). Twenty different genera of bacteria were identified by gas chromatography from 73 bacterial isolates from mosquito midguts. Pantoea agglomerans (Enterobacter agglomerans) was the most common species identified. There was no association between gram-negative bacteria in the midgut and P. falciparum sporozoites in field-collected An. gambiae s.l. and An. funestus. However, An. funestus females that harbored gram positive bacteria were more likely to be infected with sporozoites compared with those with no cultivable bacteria or gram negative bacteria in their midguts. Habitat-related variation in the prevalence of diverse types of bacteria in mosquitoes could influence malaria parasite development in mosquitoes and corresponding sporozoite prevalence.
authors.affiliation: Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA 70112, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Straif
authors.forename: C N
authors.initials: CN
authors.lastname: Mbogo
authors.forename: A M
authors.initials: AM
authors.lastname: Toure
authors.forename: E D
authors.initials: ED
authors.lastname: Walker
authors.forename: M
authors.initials: M
authors.lastname: Kaufman
authors.forename: Y T
authors.initials: YT
authors.lastname: Toure
authors.forename: J C
authors.initials: JC
authors.lastname: Beier
mesh_terms: D000818:Animals; D000852:Anopheles / Q000382:microbiology*; D004064:Digestive System / Q000382:microbiology*; D004755:Enterobacteriaceae / Q000302:isolation & purification; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D007303:Insect Vectors; D007630:Kenya; D016778:Malaria, Falciparum / Q000453:epidemiology*; D008302:Mali; D015995:Prevalence