14 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 



eastern Department of Jutiapa. The population of the Huehuetenango 

 disease zone has been estimated as 3,500, of which almost 40 percent 

 are infected with onchocerciasis. Undoubtedly there are still other 

 onchocerciasis zones in Guatemala yet to be discovered. 



Yepocapa onchocerciasis zone. — For the sake of convenience the 

 principal onchocerciasis zone will hereafter be referred to as the Yepo- 



Map 5. 



capa Zone, since it is at San Pedro Yepocapa (approximately 91° W. 

 longitude and 14° 30' N. latitude). Department of Chimaltenango, that 

 the center of investigations was established. The town itself is situated 

 at the highest elevation at which the disease is found, approximately 

 midway between the western and eastern limits of the disease zone. 

 Yepocapa was chosen as a desirable center of activity because of its 

 proximity to the infected regions and because it can be reached from 

 Guatemala City on a vehicular road. A substation was also in opera- 

 tion at San Bernabe Acatenango, 18 road miles from Yepocapa, from 



