Molecular monitoring and assessment of Onchocerciasis control in Mexico with the application of current and novel diagnostic approaches

Abstract

The main objetive of the present study was to evaluate the transmission of O. volvulus in the endemic communities of Southern Chiapas and Northern Chiapas in Mexico. In N. Chiapas, the ivermectin mass treatment had been halted in 2008 based on the entomological data collected from this focus in 2006 showing low or no evidence for the ongoing transmission of O. volvulus. The post-treatment entomological surveillance was carried out in 2010 in four communities namely Nueva Esperanza, alta Gracia, Chimix and El Ambar. The flies were collected from morning 10:00 AM to 5:00 PM. A total of 207 body pools containing 50 bodies each were subjected to pool screen PCR assay. The prevalence of infective rate per 2000 flies being 0 and 95% UCI (0.5-12.2). The seasonal transmission potencial was found to be 0 and 95% UCI ranged from 5.4-8.6. The above results indicated that there was no-ongoing parasitive-vector contact and zero transmission was observed. Hence, OEPA declared the elimination of onchocerciasis from N. Chiapas focus of Mexico in 2011.