Fighting Disease: Brazil
Eliminating Onchocerciasis From the Americas
Current status: Transmission ongoing
Brazil's last remaining transmission zone for onchocerciasis, also known as river blindness, is the Amazonas Focus, a densely forested area bordering Venezuela. Along with the Venezuelan South Focus, it comprises the Yanomami region, a contiguous transmission zone straddling the international border. The migratory Yanomami people move fluidly from one side of the border to the other and are exposed to the parasitic disease as they travel throughout the Amazon. Providing medicine and health education in this area presents many challenges as it is remote, insecure, and highly endemic. Consequently these two foci are the last in the Americas in which active transmission still occurs.
In 1996, the first year of mass drug administration in Brazil, 1,276 Mectizan® treatments (donated by Merck) were distributed. This was vastly short of the amount needed to treat the eligible population of 4,500 twice-yearly to prevent the onset of blindness. Between 2001 and 2013, the Brazilian program administered 24 semiannual treatments reaching at least 85 percent coverage. Consistently maintaining this level of coverage is vital to the eventual elimination of river blindness. The latest surveys show that Brazil is close to suppressing transmission in its shared part of the Yanomami region. Currently, quarterly treatments are being provided to 10 areas within Brazil's Amazonas focus, and prevalence of infection dropped from 14.7 percent in 2007 to 4 percent in 2012.
A strong partnership between the Brazilian and Venezuelan governments remains a crucial factor in elimination of river blindness in the shared Yanomami area. At the 67th session of the World Health Assembly (held May 19-24, 2014) the Brazilian and Venezuelan ministers of health signed a formal agreement to coordinate the effort towards elimination along their border. Under this agreement they will also work with partners including The Carter Center's Onchocerciasis Elimination Program for the Americas (OEPA), Merck's Mectizan® Donation Program, and the World Health Organization/Pan American Health Organization to reach this goal.
To eliminate and prevent river blindness, every affected person in every village, including this Yanomami child, must be reached and repeatedly treated with the medication Mectizan®. (Credit: Carter Center)