Wednesday, March 19, 2008 - 11:20 AM

Oregon Pertussis Guideline: Before and After

Juventila Liko, Immunization Program, Oregon Public Health Division, Portland, OR, USA and Paul F. Lewis, Acute and Communicable Disease Prevention, Oregon Public Health Division, Portland, OR, USA.

Learning Objectives for this Presentation:
By the end of the presentation participants will be able to:
Understand the epidemiology of pertussis in Oregon.
Describe the pertussis prophylaxis rate after a change in Public Health (PH) recommendations.
Describe the acceptability of the recommendations by Local Health Departments (LHD).

In 2004, reported pertussis incidence in Oregon reached its highest level since 1959. Contact tracing and facilitating antibiotic prophylaxis became a large burden for LHDs. In May 2005, Oregon PH recommendations were revised to focus on protecting infants and pregnant women, based on the Canadian and European models.

To describe changes and impact of the new pertussis guidelines in Oregon.

A retrospective review was conducted of patients diagnosed with pertussis from July to December 2004 and from July to December 2005. A survey of LHDs was conducted to assess the impact of the new guideline.

In 2004, 384 pertussis cases were reported with an average of 5 contacts per case. In 2005, 150 cases were reported and 4 contacts were identified for each case. This review found a significant drop in prophylaxis prescriptions from 84% of contacts in 2004 to 39% in 2005 (RR=1.8; 95% CI 1.73-2.04; p<0.001). In 2005, there was a significant increase in the proportion of infants and pregnant women identified (RR=2.1 95% CI 1.74-2.74; p<0.001). The survey of the LHDs found that the guideline is self-explanatory (94%) and that less time was spent on case investigation (70%) than prior to the change.

The revised pertussis guideline has decreased the number of prescriptions for prophylaxis per case and has been well-received by LHDs. The new guideline was not associated with an increase in the statewide rate of pertussis or in the rate of pertussis in infants.