Wayne Staggs, MS
Epidemiology Resource Center
Indiana State Department of Health

Following the recommendation of the ISDH Emerging Infectious Disease Committee, voluntary surveillance of invasive pneumococcal disease began during the summer of 1998 in Indiana. Pneumococcal disease is a serious disease caused by the bacteria Streptococcus pneumoniae. It is the leading cause of bacterial meningitis in children and causes approximately 3,000 cases of meningitis and 50,000 cases of bacteremia in all age groups (1).

As part of the voluntary reporting system, laboratories were asked to submit reports of invasive pneumococcal disease and the sensitivity report of each isolate. Prior to this statewide request, reports were received at the ISDH with two counties (Marion and Vanderburgh) providing approximately 85% of the reporting. Two hundred reports were received in 1997, increasing to 312 in 1998, following the midyear request for voluntary reporting. In 1999, 691 unduplicated cases (persons who were reported as having at least one isolate from a sterile site) were reported to the system. Fifty-four cases had Streptococcus pneumoniae isolated from two separate sterile sites. The following report describes the 691 cases and their isolates.

Isolates were obtained from nine different sterile sites. Figure 1 shows the percentage from each site based on the 745 sterile sites from which Streptococcus pneumoniae was isolated (sterile sites with less than three isolates identified are classified as "Other."

The database was sorted by county for specific variables, such as specimen source (the number of cases does not always add up to the total as some variables are not always reported). As can be seen in the table below, numerous reports have been received from many counties, while reports have not been as forthcoming from other counties.

Drug Resistance has become an emerging world problem in the treatment of Streptococcus pneumoniae invasive disease. In the U.S., drug resistance has increased substantially in the last 15 years. Investigations by CDC and others indicate that resistance varies regionally and as many as 30% of isolates are resistant to penicillin (2,3). Drug sensitivity profiles were received on 86% of 1999 Indiana cases. Of those cases with sensitivity data available, intermediate or high level resistance to penicillin was found in 27.4% of cases. This percent increases to 37.4% in cases less than 6 years of age. Table 2 depicts the penicillin resistance levels of isolates found in blood and cerebral spinal fluid in all ages and children less than six years of age.

To better understand the rate of resistance in Indiana counties, Table 3 lists the number of isolates and their sensitivity pattern by county. Sensitivity data were received on 84% of all cases reported.

Completeness and accuracy of data is of critical importance for a functional and useful surveillance system. Feedback from such data as contained in this report is only as good as the data being supplied to the system. The following table depicts the state rates for completeness of data. Based on the 691 individual cases completeness of data is shown in the table below.

ISDH staff would like to thank those individuals, laboratories, and agencies who have helped support this voluntary reporting system.

1. Centers for Disease Control and Prevention, Recommendations of the Advisory Committee on Immunization Practices (ACIP): Prevention of Pneumococcal Disease. MMWR 1997;46(No. RR-8)
2. Duchin JS, Breiman RF, Diamond A, et al. High prevalence of multi-drug resistant Streptococcus pneumoniae among children in a rural Kentucky community. Pediatric Disease Journal 1995;14:745-50
3. CDC. Prevalence of penicillin resistant Streptococcus pneumoniae - Connecticut, 1992-93. MMWR 1194;43:216-17, 223.