This study aims to estimate the risk factors associated with pertussis/whopping cough infection among infants less than one year of age in a United States (U.S.) commercially insured population. The study will utilize a large research data base associated with a geographically diverse U.S. health plan not limited by one geographic area or disease outbreak to evaluate pertussis in infants between 2005 and 2010. Healthcare costs and utilization among infants with a reported diagnosis of pertussis/whooping cough stratified by the number of DTaP vaccinations received prior to infection will also be reported.

This study will utilize the OptumInsight proprietary research database which contains enrollment and claims data for individuals enrolled in commercial health plans to estimate the measureable demographic, clinical and historical economic risk factors that may be associated with medically diagnosed pertussis/whooping cough infection among commercially insured infants less than one-year of age. Healthcare costs and utilization among infants with a reported diagnosis of pertussis/whooping cough will be stratified by the number of DTaP vaccinations received prior to infection.

Inclusion Criteria:

• Date of birth between July 1, 2005 and September 30, 2010.
• Enrollment in a commercial health plan within one month of birth.
• Known sex and geographic region.
• Infants will be included as a pertussis/whooping cough case if they meet the diagnosis criteria Infants not identified as a pertussis/whooping cough case are eligible for inclusion as a control.

Exclusion Criteria:

• Enrollment does not include medical and pharmacy coverage.

Infants less than one-year of age born between 2005 and 2010 in a U.S. commercially insured population contained within the optum propertity database