Tdap Uptake at a Pediatric Teaching Hospital during a Pertussis Epidemic

Background: Pertussis in pediatric healthcare workers (HCWs) is a concern because it can be transmitted to infants who may develop severe or fatal disease.  In 2006, the Advisory Committee on Immunization Practices recommended Tdap for all HCWs; yet subsequent studies have shown low Tdap immunization rates. In March 2010, pertussis cases increased in California, and an epidemic was declared in June. By November, over 6000 pertussis cases and 10 infant deaths were reported to California Department of Public Health (CDPH). Since August, three HCWs at our 190-bed pediatric teaching hospital were diagnosed with pertussis.  Contact investigations identified 160 exposed HCWs and 465 potentially exposed patients with a similar number of family members. Two secondary infections developed among HCWs, but none among patients. In response to this epidemic, interventions to increase Tdap immunization rates were implemented and further intensified after the identification of pertussis among HCWs.

Objective: To assess the impact of interventions to increase HCW immunization rates in a pediatric teaching hospital before and during a pertussis epidemic.

Methods: Tdap has been recommended to our HCWs since January 2006. Tdap vaccine is offered to new staff and during Employee Health (EH) drop-in hours. In April 2010, CDPH reiterated the importance of Tdap for HCWs.  Educational efforts to promote Tdap were implemented, including presentations at manager meetings, email alerts and widespread use of signage.  After the HCW pertussis cases were identified in August 2010, efforts to immunize intensified. Hospital leadership strongly encouraged all HCWs to receive Tdap or sign a declination and made a financial commitment and goal to attain 100% compliance.  Immunization clinics were held, designated nurse vaccinators targeted clinic areas and wards, and roving immunization teams were deployed. Vaccine compliance reports were reviewed by managers and administrators every two weeks.

Results: On 4/1/2010, baseline immunization and declination rates among HCWs including all employees and hospital-based physicians were 29% and 2%, respectively. By 8/1/2010, educational interventions had increased rates to 36% and 3%, respectively. After intensified measures were implemented in early September, and by 11/1/2010, the Tdap immunization rate increased to 73% with a declination rate of 11%, for an overall compliance rate of 84%.

Conclusions: Tdap uptake among HCWs at our hospital prior to the pertussis epidemic was poor. Immunization rates improved marginally early in the pertussis epidemic despite increased education of staff. Active interventions were necessary to increase Tdap uptake. Despite these efforts, 27% of HCWs remain unimmunized. To further improve immunization rates, pediatric healthcare facilities may need to consider making Tdap immunization a condition of employment.