Wednesday, March 19, 2008

Reported Pertussis-related Deaths to the National Notifiable Diseases Surveillance System (NNDSS) and the Centers for Disease Control and Prevention (CDC) in the United States, 20002005

Tejpratap S.P. Tiwari1, Kashif Iqbal1, Kristin Brown1, Pamela Srivastava1, and Andrew L. Baughman2. (1) National Center for Immunization and Respiratory Diseases/DBD/MVPD, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, USA, (2) National Center for Immunization and Respiratory Diseases/DBD/Biostatistics Office, Centers for Disease Control and Prevention, Atlanta, USA

Learning Objectives for this Presentation:
By the end of the presentation, participants will be able to understand the characteristics of pertussis-related deaths.

Despite childhood coverage rates >95% with five doses of pertussis vaccine, reported pertussis cases and pertussis-related deaths increased in the United States during the 1990s.

To describe the clinical characteristics and epidemiologic trends of pertussis-related deaths from 2000 to 2005.

We analyzed data from NNDSS and available medical records for pertussis-related deaths reported to the CDC from 2000 through 2005.

From 20005, 140 pertussis-related deaths were reported to CDC compared to 103 deaths during 19909. Pertussis was considered positive by culture (49%), PCR (39%), DFA (6%), and epidemiologic linkage (10%). Overall, 54% fatal cases were females. One hundred and thirty one fatalities (94%) occurred among infants aged <1 year and 126 (90%) were aged <4 months; six deaths were aged >7 years and had preexisting co-morbidities. One hundred and thirty two cases (94%) were hospitalized and 72% required mechanical ventilation. Extracorporeal membrane oxygenation was performed in 40 infants (30%). Reported complications included pneumonia (92%), encephalopathy (5%) seizures (7%), co-infections (30%), and pulmonary hypertension (35%). Ninety-four percent cases were unvaccinated, 3% received >1 dose; vaccination status of 3% fatalities was unknown. Of 123 infants with ethnicity data, 49% were Hispanic. Mortality rate among Hispanic infants (7.2/100,000) was higher than among non-Hispanics (2.0/100,000). Among 101 infants with known gestational age, 39% were born at <37 weeks. The median maternal age was 22 years (range, 13-47, n=94). In 64 (49%) infant deaths, a parent, sibling or grandparent had an antecedent cough-illness in the household.

Reported pertussis-related deaths increased during 2000-5 compared to the 1990s. Studies are needed to evaluate risk factors for fatal pertussis. Household contacts of infants should receive a dose of an age-appropriate pertussis vaccine to help protect infants from acquiring pertussis.