Background: Tetanus, diphtheria and acellular pertussis immunization of infant contacts (cocooning) is recommended by the Centers for Disease Control and Prevention to prevent infant pertussis. We determined whether implementing a cocooning program at Ben Taub General Hospital, Houston, reduced severe pertussis in young infants.
Methods: Infants ≤6 months of age, diagnosed with pertussis (determined by International Classification of Diseases, Ninth Revision codes and microbiology records) at 4 hospitals, and born at times when only postpartum women (January 2008 through May 2009) and all infant contacts (June 2009 through August 2011) were offered tetanus, diphtheria and acellular pertussis vaccine at Ben Taub General Hospital were compared with infants born preintervention (May 2004 through December 2007).
Results: One hundred ninety-six (49%) infants with pertussis were born preintervention, 140 (35%) during maternal postpartum (PP) and 64 (16%) during cocooning (C) periods. Infants were similar in age at diagnosis (81.2 vs. 71.3 [PP] vs. 72.5 [C] days; P 0.07), sex (male 59% vs. 51% [PP] vs. 48% [C]; P 0.17), hospitalization (68% vs. 71% [PP] vs. 78% [C]; P 0.27) and outcome (2 deaths in the PP period; P 0.15), but more were admitted to intensive care units during cocooning (24% vs. 35% [PP] vs. 68% [C]; P < 0.001). Similar proportions of infants were born at Ben Taub General Hospital throughout the study (8% vs. 9% [PP] vs. 5% [C]; P 0.53).
Conclusions: Postpartum immunization and cocooning did not reduce pertussis illness in infants ≤6 months of age. Efforts should be directed toward increasing tetanus, diphtheria and acellular pertussis immunization during pregnancy, combined with cocooning, to reduce life-threatening young infant pertussis.
From the *Department of Pediatrics, Baylor College of Medicine; †Ben Taub General Hospital; ‡Center for Vaccine Awareness and Research, Texas Children’s Hospital; and §University of Texas Health Sciences Center at Houston, Houston, TX.
Accepted for publication June 28, 2014.
This work was supported by a research grant from Sanofi Pasteur, Inc. The Ben Taub General Hospital cocooning program was supported through grants from the Baylor-Methodist Community Health Fund and the Harris County Hospital District Foundations and through donated Tdap vaccine from Sanofi Pasteur.
C.M.H. is the recipient of research grants from Sanofi Pasteur and Novartis Vaccines and serves on an Advisory Board for Novartis Vaccines and Pfizer Inc. L.A.C. is on a Speaker’s Bureau for Sanofi Pasteur. All other authors have no conflicts to disclose. All authors have approved the final article.
Address for correspondence: C. Mary Healy, MD, 1102 Bates Street, Suite 1120, Houston, TX 77030. E-mail: firstname.lastname@example.org.