CDC reports near eradication National Immunization Program, CD C. (1999).Achievements in public health, 1900–1999 impact of vaccines universally recommended for children—United States, 1990–1998. Morbidity and Mortality Weekly Report, 48(12), 243–248. По данным сайта http://www.cdc.gov/mmwr/preview/mmwrhtml/00056803.htm#00003753.htm.
