Pertussis has been on the rise worldwide for more than 20 years. Waning immunity may be the major cause for the resurgence of this disease. Adolescents and adults have become the vectors of pertussis, with newborns and infants less than 12 months of age at greatest risk for morbidity and mortality. Health care providers need to become aware of a vaccine strategy called cocooning that provides the needed vaccines to individuals who have contact with newborns and infants. Cocooning can protect our most vulnerable populations from pertussis and other vaccine -preventable diseases in the 21st Century.