| geographical distribution of the prevalence of nodules of onchocerca volvulus in guatemala over the last four decades. | in guatemala a national nodulectomy campaign has been carried out since 1935 in three operational areas, namely the eastern, central and western endemic zones. the prevalence of nodules was calculated in each 1 km grid square in these zones in each decade and plotted on mesh maps. a total of nine foci of high endemicity, three in each operational area, was found in the decade 1940-49. nodule prevalence was concentric in each endemic focus; high in the centre and gradually falling towards periphe ... | 1986 | 3704472 |
| elimination of onchocercia volvulus transmission in the santa rosa focus of guatemala. | to eliminate transmission of onchocerca volvulus, semiannual mass treatment with ivermectin (mectizan; donated by merck & co) has been underway in guatemala since 2000. we applied the 2001 world health organization (who) elimination criteria in the santa rosa focus of onchocerciasis transmission in guatemala (10,923 persons at risk). no evidence of parasite dna was found in 2,221 simulium ochraceum vectors (one-sided 95% confidence interval [ci], 0-0.086%), and no igg4 antibody positives to reco ... | 2007 | 17690408 |