title: No depletion of Wolbachia from Onchocerca volvulus after a short course of rifampin and/or azithromycin.
abstract: Endosymbionic Wolbachia bacteria inside adult Onchocerca volvulus worms (causing river blindness) are necessary for female worm fertility. We evaluated whether rifampin and/or azithromycin used in a five-day course could kill Wolbachia. In an open-label trial in Guatemala, 73 patients with 134 palpable onchocercal nodules were randomized into four treatment groups: rifampin, azithromycin, a combination of the two drugs, and controls (multivitamins). After five days of antibiotic treatment, all participants received a single dose of ivermectin on day 6. Nine months after treatment, the nodules were removed and the worms were examined. Skin snips to determine microfilariae were obtained at baseline and nine months. There were no significant differences between any of the treatment groups in the condition of the worms in the nodules, the presence of Wolbachia surface protein, or the number of microfilariae in skin. Short courses with these antibiotics will not clear Wolbachia from O. volvulus.
authors.affiliation: Centers For Disease Control and Prevention, Atlanta, Georgia 30333, USA. frichards@cdc.gov
authors.forename: Frank O
authors.initials: FO
authors.lastname: Richards
authors.forename: Josef
authors.initials: J
authors.lastname: Amann
authors.forename: Byron
authors.initials: B
authors.lastname: Arana
authors.forename: George
authors.initials: G
authors.lastname: Punkosdy
authors.forename: Robert
authors.initials: R
authors.lastname: Klein
authors.forename: Carlos
authors.initials: C
authors.lastname: Blanco
authors.forename: Beatriz
authors.initials: B
authors.lastname: Lopez
authors.forename: Carlos
authors.initials: C
authors.lastname: Mendoza
authors.forename: Alfredo
authors.initials: A
authors.lastname: Domínguez
authors.forename: Jeannette
authors.initials: J
authors.lastname: Guarner
authors.forename: James H
authors.initials: JH
authors.lastname: Maguire
authors.forename: Mark
authors.initials: M
authors.lastname: Eberhard
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017963:Azithromycin / Q000008:administration & dosage* / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007559:Ivermectin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D017181:Onchocerca volvulus / Q000187:drug effects / Q000382:microbiology*; D009855:Onchocerciasis / Q000188:drug therapy / Q000469:parasitology; D012293:Rifampin / Q000008:administration & dosage* / Q000627:therapeutic use*; D020577:Wolbachia / Q000187:drug effects*
chemical_list: D000871:Anthelmintics; D000900:Anti-Bacterial Agents; D007559:Ivermectin; D017963:Azithromycin; D012293:Rifampin