Emergence of Onchocerca volvulus microfilariae from skin snips before and after treatment of patients with ivermectin.
As ivermectin is supposed to have a paralyzing effect, the emergence of Onchocerca volvulus microfilariae from skin snips before and after treatment was examined. Before treatment 79.8% of the microfilariae emerged from the skin snips. Three days after treatment the microfilarial skin density had dropped to 83% (placebo), 28% (100 microgram/kg ivermectin), 19% (150 micrograms/kg) and 14% (200 micrograms/kg) of the pretreatment values but the microfilarial emergence was not altered distinctly. The majority of the remaining microfilariae were mobile and able to leave the biopsy. Only a slight, but significant, dose-dependent trend of reduced emergence could be shown. From our results no direct support is derived for the hypothesis that O. volvulus microfilariae are paralyzed or immobilized by ivermectin.
Mössinger
J
J
Tropenmedizinisches Institut, Universität Tübingen, FRG.
Schulz-Key
H
H
Dietz
K
K
D000704:Analysis of Variance; D000818:Animals; D002986:Clinical Trials as Topic; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006801:Humans; D007559:Ivermectin / Q000494:pharmacology / Q000627:therapeutic use*; D008842:Microfilariae / Q000187:drug effects / Q000502:physiology; D009854:Onchocerca / Q000187:drug effects* / Q000502:physiology; D009855:Onchocerciasis / Q000188:drug therapy* / Q000469:parasitology; D012044:Regression Analysis; D012867:Skin / Q000469:parasitology*
D007559:Ivermectin