1. GAS Supplemental Surveillance Form
Data collection for this supplemental form was conducted for all invasive GAS cases with culture dates between January 1, 2002 and December 31, 2003. Information recorded included variables that make up the 1993 streptococcal toxic shock syndrome (STSS) case definition, surgical history, pregnancy/delivery history and residence in a long term care facility.
Group A Streptococcus case report form and supplemental surveillance data were analyzed as a summer project by a graduate student in 2004 and summarized in a poster. Of interest, this supplemental surveillance identified 20/24 (83%) additional 2002 cases of GAS STSS and 13/21 (62%) additional 2003 cases that had not been identified by medical record abstraction based on discharge diagnoses alone. The results were presented as a poster at the national IDSA conference held in October, 2005.
All STSS cases identified by supplemental surveillance met the 1993 case definition of the Working Group on Severe Streptococcal Infections (JAMA 1993; 269: 390-1).
2. Evaluation of Compliance with 1998 Consensus Guidelines for the Prevention of Perinatal Group B Streptococcal (GBS) Disease and the Effectiveness of Prevention Strategies
Consensus guidelines to prevent perinatal GBS disease, a leading cause of infant morbidity and mortality, were released in 1996, recommending the use of one of two strategies for identification of candidates for chemoprophylaxis during labor: a risk-based protocol and a screening-based protocol.
The primary objectives of this study to assess clinician compliance with the 1996 guidelines, to identify potential barriers to prevention and to assess the effectiveness of the alternative strategies recommended in the consensus guidelines. For this study a representative sample of maternal hospital records in nine EIP states were reviewed.
In our site, 575 maternal records, including 29 mothers of cases of early-onset GBS disease, were abstracted from hospitals that had labor and delivery services in 1998-1999 in Alameda, Contra Costa, and San Francisco counties. Data abstracted included demographic, prenatal, and intrapartum information from maternal labor and delivery charts. These data were collected from a random, stratified sample of live births. California data analysis revealed that 46 percent of deliveries were exposed to the screening based strategy. Adjusted multivariable analyses determined that the screening-based approach was protective relative to the risk-based approach (adjusted OR=0.34, 95% C.I.= 0.12-0.98)). Our findings were similar to the results of analyses of the national data (including all 9 EIP sites). Results from the CA data analyses entitled “Prevention of Perinatal Early-Onset GBS Disease: The California Experience” were presented at the American Public Health Association’s National Conference in 2003.
3. Case-Control Study: Effectiveness of Pneumococcal Conjugate Vaccine in Children
In February 2000, a seven-valent protein–polysaccharide pneumococcal conjugate vaccine (Prevnar,Wyeth Lederle Vaccines) was licensed for use in infants and young children in the United States. This was the first vaccine that promised efficacy against pneumococcal disease in this high-risk age group. One of the main goals of the study was to measure overall effectiveness of this pneumococcal conjugate vaccine against invasive disease among children 3 to 59 months old. The study was conducted at ten Emerging Infections Program (EIP) sites in the United States. Cases and controls were enrolled from January 1, 2001 through June 30, 2004. This post licensure study confirmed pre-licensure results, finding the vaccine highly effective in protecting infants and young children against invasive pneumococcal disease. Data were analyzed at CDC and the results were published as a paper entitled “Effectiveness of seven-valent pneumococcal conjugate vaccine against invasive pneumococcal disease: a matched case-control study”. (Lancet. 2006; 368(9546): 1495-502).
4. Risk Factors for Infection with Streptococcus pneumoniae Resistant to Fluoroquinolones
The objective of this study was to determine risk factors for invasive infection with Streptococcus pneumoniae (SPN) resistant to fluoroquinolones. This study was conducted in response to concerns about fluoroquinolones being used increasingly as empiric therapy of community-acquired pneumonia in adults. This fluuroquinilone use was being driven by concerns over pneumococcal resistance to other antimicrobial classes. As a result, fluoroquinolone resistant strains of invasive pneumococcal disease in adults were emerging. CEIP enrolled a total of 24 cases and controls from February 1, 2002 through September 30, 2004. Data analysis was conducted at CDC and results were presented as an abstract entitled “Risk Factors for Fluoroquinolone-resistant S. pneumoniae Infections in Adults” at the 45th International Conference on Antimicrobial Agents and Chemotherapy in December 2005.
5. Evaluation of Adherence to the 2002 Revised Guidelines for the Prevention of Perinatal Group B Streptococcus Disease
The objective of this study was to characterize adherence to guidelines for the prevention of perinatal disease due to Group B Streptococcus (GBS), hepatitis B virus (HBV), HIV, rubella, syphilis, Chlamydia trachomatis, gonococcus, and bacterial vaginosis (BV). A population-based sample of labor and delivery records in 10 U.S. states that participate in active GBS disease surveillance was audited. The sampling frame included all births to surveillance-area residents during 2003–2004 as reported to the Vital Records Department in each state. From this frame, we selected a stratified random sample of approximately 6000 live births nationwide. (669 records were abstracted at CEIP.) For each birth, we abstracted information on adherence to prevention guidelines for each infectious agent from the labor and delivery record . The results of this evaluation were used to identify missed opportunities for prevention, formulate recommendations for increased uptake of the guidelines, prioritize efforts to promote appropriate prophylaxis, and further inform present prevention strategies. Data were analyzed at CDC and the results were published in two papers. The first paper is entitled “Evaluation of Universal Antenatal Screening for Group B Streptococcus” (New Engl J Med 2009l 360(25):2626-35). A secondary analysis was published in a paper entitled “Effectiveness of Intrapartum Antibiotic Prophylaxis for Prevention of Early-Onset Group B Streptococcal Disease” (Obstretrics and Gynecology, 2013; 121(3): 570-7.