Evaluation of national reporting of invasive pneumococcal disease (IPD)

Learning Objectives for this Presentation:
By the end of the presentation participants will be able to:
1. Understand what data is reported in the National Notifiable Diseases Surveillance System (NNDSS)
2. Identify areas in which state-based reporting of invasive pneumococcal disease (IPD) may be improved

Background:
Cases of IPD among children <5 years and invasive drug-resistant Streptococcus pneumoniae (DRSP) among all ages are reportable to NNDSS. The Council of State and Territorial Epidemiologists recommended reporting to track the impact of pneumococcal vaccination and other prevention programs. Three states do not require reporting IPD among children <5 years, three others do not require reporting of DRSP, and five require neither.

Objectives:
We evaluated NNDSS to identify opportunities to enhance monitoring of IPD.

Methods:
We used 2001 CDC guidelines for evaluating public health surveillance systems. NNDSS data from 2006 were compared with 2004 and 2005 data from Active Bacterial Core surveillance (ABCs), an active laboratory- and population-based surveillance system.

Results:
1861 IPD cases among children <5 years and 3308 DRSP cases were reported to NNDSS from states where these conditions were reportable. Nine states accounted for 52% of total IPD cases; four states reported 57% of DRSP. Seven and 15 states, respectively, reported no IPD or DRSP cases. According to ABCs, an estimated 4081 cases of IPD among children <5 years occurred in the U.S. in 2005, and 12,300 cases of IPD caused by DRSP occurred in 2004. Therefore, only 46% of the estimated IPD among children <5 years and 27% of estimated DRSP cases were captured by NNDSS.

Conclusions:
Data from NNDSS does not enable accurate disease burden assessments or evaluation of immunization programs. Adherence to reporting recommendations was suboptimal; a few states accounted for most reported cases. NNDSS should be enhanced to provide an assessment of the impact of new pneumococcal vaccines expected to be available in the near future.