Learning Objectives for this Presentation:
By the end of the presentation participants will be able to describe how mandatory laboratory reporting of influenza has affected one state's influenza surveillance program.

Background:
Influenza became a laboratory-reportable condition in Arizona in October 2004. This surveillance source supplements other statewide surveillance, such as the influenza-like illness (ILI) sentinel provider network, state laboratory testing of isolates or respiratory submissions, and calls to selected laboratories. These data were anticipated to substantially impact Arizona's influenza surveillance and decisions such as issuing provider and public alerts.

Objectives:
To describe the impact of laboratory-reporting of influenza on surveillance and communications during the 2004-2005 influenza season.

Methods:
Laboratories submit positive test results of reportable conditions to the Arizona Department of Health Services; influenza reports are analyzed weekly during the season along with data from the state laboratory and the sentinel provider network. Data were compared among the three sources of routine influenza reporting using a retrospective evaluation to specifically determine the effect of laboratory reporting on defining influenza activity levels and prevention and communication decisions.

Results:
In prior years, state laboratory data was the main source of confirmed influenza data. The addition of mandatory lab reporting resulted in detection of more cases early in the season and continued identification of activity later in the season. In the weeks close to Arizona's peak, laboratory data and state lab data showed good concordance. In addition, laboratory data from both sources were at elevated levels prior to ILI activity increasing above baseline levels. Differences between counties will be discussed; lab reporting helped obtain information from a wider geographic area.

Conclusions:
The addition of mandatory influenza laboratory reporting to traditional influenza surveillance tools has provided more foundation and confidence for decisions made at the state level. Laboratory-reporting of cases has enhanced influenza monitoring in the state and thus public health responses.