First pertussis vaccine dose and prevention of infant mortality.
BACKGROUND
American infants are at highest risk of severe pertussis and death. We investigated the role of ≥1 pertussis vaccinations in preventing pertussis-related deaths and risk markers for death among infants aged <42 days.


METHODS
We analyzed characteristics of fatal and nonfatal infant pertussis cases reported nationally during 1991-2008. Infants were categorized into 2 age groups on the basis of eligibility to receive a first pertussis vaccine dose at age 6 weeks; dose 1 was considered valid if given ≥14 days before illness onset. Multivariable logistic regression was used to estimate the effect of ≥1 pertussis vaccine doses on outcome and risk markers.


RESULTS
Pertussis-related deaths occurred among 258 of 45 404 cases. Fatal and nonfatal cases were confirmed by culture (54% vs 49%) and polymerase chain reaction (31% vs 27%). All deaths occurred before age 34 weeks at illness onset; 64% occurred before age 6 weeks. Among infants aged ≥42 days, receiving ≥1 doses of vaccine protected against death (adjusted odds ratio [aOR]: 0.28; 95% confidence interval [CI]: 0.11-0.74), hospitalization (aOR: 0.69; 95% CI: 0.63-0.77), and pneumonia (aOR: 0.80; 95% CI: 0.68-0.95). Risk was elevated for Hispanic ethnicity (aOR: 2.28; 95% CI: 1.36-3.83) and American Indian/Alaska Native race (aOR: 5.15; 95% CI: 2.37-11.2) and lower for recommended antibiotic treatment (aOR: 0.28; 95% CI: 0.16-0.47). Among infants aged <42 days, risk was elevated for Hispanic ethnicity and lower with recommended antibiotic use.


CONCLUSIONS
The first pertussis vaccine dose and antibiotic treatment protect against death, hospitalization, and pneumonia.
Meningitis and Bacterial Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, and tit2@cdc.gov.
Tejpratap S P
TS
Tiwari
Division of Global HIV/AIDS, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia.
Andrew L
AL
Baughman
Meningitis and Bacterial Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, and.
Thomas A
TA
Clark
D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D008297:Male; D010567:Pertussis Vaccine / Q000008:administration & dosage*; D014917:Whooping Cough / Q000401:mortality* / Q000517:prevention & control*
D010567:Pertussis Vaccine