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).

Background:
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.

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

Methods:
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.

Results:
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.

Conclusions:
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.