1. Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
2. Division of Global Health Protection, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
3. Centers for Disease Control and Prevention Central America Regional Office, Guatemala City 01015, Guatemala
4. U.S. Agency for International Development (USAID), Guatemala City 01016, Guatemala
5. Ministerio Salud Publica y Asistencia Social, Guatemala City 01011, Guatemala
6. Council of Ministers of Health of Central America, San Salvador, El Salvador