PubMed Health⌕ Search

Biomedical subjects

Ruth Lynfield

Publications and source records attributed to Ruth Lynfield.

28 records · Page 2Linked to original sources
PubMed2004

Impact of childhood vaccination on racial disparities in invasive Streptococcus pneumoniae infections.

CONTEXT: Historically, incidence of pneumococcal disease in the United States has been higher among blacks than among whites. Following recommendation of a new 7-valent pneumococcal conjugate vaccine for children in October 2000, the incidence of invasive pneumococcal disease has declined dramatically, but the impact of vaccination on racial disparities in incidence of pneumococcal disease is unknown. OBJECTIVE: To assess the effect of conjugate vaccine introduction on rates of pneumococcal disease among whites and blacks in the United States. DESIGN, SETTING, AND PATIENTS: Analysis of data from the Active Bacterial Core Surveillance (ABCs)/Emerging Infections Program Network, an active, population-based surveillance system in 7 states. Patients were 15,923 persons with invasive pneumococcal disease occurring between January 1, 1998, and December 31, 2002. MAIN OUTCOME MEASURES: Age- and race-specific pneumococcal disease incidence rates (cases per 100 000 persons), rate ratios, and rate differences. RESULTS: Between 1998 and 2002, annual incidence rates for invasive pneumococcal disease decreased from 19.0 to 12.1 cases per 100 000 among whites and from 54.9 to 26.5 among blacks. Due to these declines, 14,730 fewer cases occurred among whites and 8780 fewer cases occurred among blacks in the United States in 2002, compared with 2 prevaccine years, 1998 and 1999. Before vaccine introduction, incidence among blacks was 2.9 times higher than among whites (95% confidence interval [CI], 2.7-3.0); in 2002, the black-white rate ratio had been reduced to 2.2 (95% CI, 2.0-2.4). Incidence among black children younger than 2 years went from being 3.3 times higher (95% CI, 3.0-3.7) than among white children in the prevaccine period to 1.6 times higher (95% CI, 1.1-2.2) in 2002. By 2002, 74% of white children and 68% of black children aged 19 to 35 months in the 7 states had received at least 1 dose of pneumococcal conjugate vaccine; 43% of white and 39% of black children received 3 or more doses. CONCLUSION: Although blacks remain at higher risk of invasive pneumococcal disease, introduction of childhood pneumococcal vaccination has reduced the racial disparity in incidence of pneumococcal disease.

Adolescent↗
PubMed2003

Comparison of community- and health care-associated methicillin-resistant Staphylococcus aureus infection.

CONTEXT: Methicillin-resistant Staphylococcus aureus (MRSA) has traditionally been considered a health care-associated pathogen in patients with established risk factors. However, MRSA has emerged in patients without established risk factors (community-associated MRSA). OBJECTIVE: To characterize epidemiological and microbiological characteristics of community-associated MRSA cases compared with health care-associated MRSA cases. DESIGN, SETTING, AND PATIENTS: Prospective cohort study of patients with MRSA infection identified at 12 Minnesota laboratory facilities from January 1 through December 31, 2000, comparing community-associated (median age, 23 years) with health care-associated (median age, 68 years) MRSA cases. MAIN OUTCOME MEASURES: Clinical infections associated with either community-associated or health care-associated MRSA, microbiological characteristics of the MRSA isolates including susceptibility testing, pulsed-field gel electrophoresis, and staphylococcal exotoxin gene testing. RESULTS: Of 1100 MRSA infections, 131 (12%) were community-associated and 937 (85%) were health care-associated; 32 (3%) could not be classified due to lack of information. Skin and soft tissue infections were more common among community-associated cases (75%) than among health care-associated cases (37%) (odds ratio [OR], 4.25; 95% confidence interval [CI], 2.97-5.90). Although community-associated MRSA isolates were more likely to be susceptible to 4 antimicrobial classes (adjusted OR, 2.44; 95% CI, 1.35-3.86), most community-associated infections were initially treated with antimicrobials to which the isolate was nonsusceptible. Community-associated isolates were also more likely to belong to 1 of 2 pulsed-field gel electrophoresis clonal groups in both univariate and multivariate analysis. Community-associated isolates typically possessed different exotoxin gene profiles (eg, Panton Valentine leukocidin genes) compared with health care-associated isolates. CONCLUSIONS: Community-associated and health care-associated MRSA cases differ demographically and clinically, and their respective isolates are microbiologically distinct. This suggests that most community-associated MRSA strains did not originate in health care settings, and that their microbiological features may have contributed to their emergence in the community. Clinicians should be aware that therapy with beta-lactam antimicrobials can no longer be relied on as the sole empiric therapy for severely ill outpatients whose infections may be staphylococcal in origin.

Adult↗
PubMed2003

Vancomycin-intermediate Staphylococcus aureus with phenotypic susceptibility to methicillin in a patient with recurrent bacteremia.

Vancomycin-intermediate Staphylococcus aureus (VISA) are an emerging problem. We observed a statistically significant inverse relationship in the MICs of vancomycin and oxacillin in S. aureus isolates from a patient undergoing hemodialysis who received 26 weeks of treatment with vancomycin during November 1999 through April 2000. All isolates were mecA positive and were indistinguishable by pulsed-field gel electrophoresis. The evolving susceptibility patterns of this strain highlight the challenges of detecting and treating VISA infections.

Bacteremia↗
PubMed2003

Decline in invasive pneumococcal disease after the introduction of protein-polysaccharide conjugate vaccine.

BACKGROUND: In early 2000, a protein-polysaccharide conjugate vaccine targeting seven pneumococcal serotypes was licensed in the United States for use in young children. METHODS: We examined population-based data from the Active Bacterial Core Surveillance of the Centers for Disease Control and Prevention to evaluate changes in the burden of invasive disease, defined by isolation of Streptococcus pneumoniae from a normally sterile site. Serotyping and susceptibility testing of isolates were performed. We assessed trends using data from seven geographic areas with continuous participation from 1998 through 2001 (population, 16 million). RESULTS: The rate of invasive disease dropped from an average of 24.3 cases per 100,000 persons in 1998 and 1999 to 17.3 per 100,000 in 2001. The largest decline was in children under two years of age. In this group, the rate of disease was 69 percent lower in 2001 than the base-line rate (59.0 cases per 100,000 vs. 188.0 per 100,000, P<0.001); the rate of disease caused by vaccine and vaccine-related serotypes declined by 78 percent (P<0.001) and 50 percent (P<0.001), respectively. Disease rates also fell for adults; as compared with base line, the rate of disease in 2001 was 32 percent lower for adults 20 to 39 years of age (7.6 cases per 100,000 vs. 11.2 per 100,000, P<0.001), 8 percent lower for those 40 to 64 years of age (19.7 per 100,000 vs. 21.5 per 100,000, P=0.03), and 18 percent lower for those 65 years of age or more (49.5 per 100,000 vs. 60.1 per 100,000, P<0.001). The rate of disease caused by strains that were not susceptible to penicillin was 35 percent lower in 2001 than in 1999 (4.1 cases per 100,000 vs. 6.3 per 100,000, P<0.001). CONCLUSIONS: The use of the pneumococcal conjugate vaccine is preventing disease in young children, for whom the vaccine is indicated, and may be reducing the rate of disease in adults. The vaccine provides an effective new tool for reducing disease caused by drug-resistant strains.

Adolescent↗
PubMed2003

Geographic diversity and temporal trends of antimicrobial resistance in Streptococcus pneumoniae in the United States.

Resistance of Streptococcus pneumoniae to antibiotics is increasing throughout the United States, with substantial variation among geographic regions. We show that patterns of geographic variation are best explained by the intensity of selection for resistance, which is reflected by differences between the proportions of resistance within individual serotypes, rather than by differences between the frequencies of particular serotypes. Using a mathematical transmission model, we analyzed temporal trends in the proportions of singly and dually resistant organisms and found that pneumococcal strains resistant to both penicillin and erythromycin are increasing faster than strains singly resistant to either. Using the model, we predict that by 1 July 2004, in the absence of a vaccine, 41% of pneumococci at the Centers for Disease Control and Prevention (CDC)'s Active Bacterial Core surveillance (ABCs) sites, taken together, will be dually resistant, with 5% resistant to penicillin only and 5% to erythromycin only.

Drug Resistance↗
PubMed2003

Prenatal screening for infectious diseases and opportunities for prevention.

OBJECTIVE: To characterize adherence with recommendations for prenatal infectious disease screening and missed opportunities for prevention of congenital and perinatal infections. METHODS: Demographic, prenatal, and peripartum information was abstracted from labor and delivery records of a random, stratified sample of live births in 1998 and 1999 to residents of eight active surveillance areas. Adherence with prenatal screening recommendations was evaluated for hepatitis B, syphilis, rubella, human immunodeficiency virus (HIV), and group B streptococcus (GBS). Characteristics of missed opportunities for disease prevention were assessed by univariate and multivariable analysis to account for survey design. RESULTS: Prenatal screening rates for hepatitis B surface antigen (HBsAg) (96.5%), syphilis (98.2%), and rubella (97.3%) were high. Areas of excess syphilis morbidity did not adhere to recommendations for third-trimester retesting. Testing rates for HIV (57.2%) and GBS (52.0%) were lower and had wide geographic variation. Postpartum rubella vaccination was documented for only 65.7% of rubella-susceptible women. Inadequate prenatal care was the single strongest predictor of missed opportunities for prenatal testing (relative risk 14.6; 95% confidence interval 6.3, 33.7). Blacks were less likely than whites to receive adequate prenatal care and prenatal tests, more likely to test positive for HBsAg and syphilis, and less likely to receive recommended prevention interventions such as postpartum rubella vaccination for susceptible women. CONCLUSIONS: Adherence to both long-standing and more recent recommendations for congenital and perinatal disease prevention can be improved, thus perhaps reducing racial disparities in the use of prenatal screening and appropriate prevention interventions.

Adolescent↗
PubMed2003

Toxoplasmosis-related knowledge and practices among pregnant women in the United States.

BACKGROUND: Infection with Toxoplasma gondii during pregnancy can lead to severe illness in the fetus. Many T. gondii infections are preventable by simple hygienic measures. METHODS: We surveyed pregnant women in the US to determine their knowledge about toxoplasmosis and their practices to prevent infection. Volunteer obstetricians selected to be demographically representative of the American College of Obstetricians and Gynecologists recruited the participants. RESULTS: Of 403 women responding to the survey, 48% indicated that they had heard or seen information about toxoplasmosis; however, only 7% were aware of being tested for the disease. Forty percent of responding women knew that toxoplasmosis is caused by an infection, but 21% thought that a poison causes it. The highest level of knowledge was about cats and T. gondii; 61% responded that the organism is shed in the feces of infected cats and 60% responded that people could acquire toxoplasmosis by changing cat litter. There was a low level of knowledge about other risk factors; only 30% of the women were aware that T. gondii may be found in raw or undercooked meat. Nevertheless, a high percentage of women indicated that they do not eat undercooked meat during pregnancy and that they practice good hygienic measures such as washing their hands after handling raw meat, gardening or changing cat litter. CONCLUSION: Except for the risk of transmission from cats, knowledge among pregnant women about toxoplasmosis is low. However, toxoplasmosis-preventive practices are generally good, suggesting that providers should continue to offer education about practices that help prevent foodborne diseases in general as well as information about preventing toxoplasmosis specifically.

Adolescent↗
PubMed2003

Prevention of perinatal group B streptococcal disease in Minnesota: results from a retrospective cohort study and new prevention guidelines.

Group B Streptococcus (GBS) is an important cause of perinatal morbidity and mortality in the United States. In 1996, guidelines from the Centers for Disease Control and Prevention (CDC) recommended that prenatal care providers either screen all pregnant women for GBS carriage and offer intrapartum antibiotic prophylaxis (IAP) to women who test positive, or offer IAP to women who have risk factors for early-onset GBS (EOGBS) disease during pregnancy. A recent multi-state retrospective cohort compared the efficacy of the 2 methods and found the screening-based method to be significantly more effective at reducing the incidence of EOGBS. One of the study sites was the 7-county Minneapolis-St. Paul metropolitan area. Analysis of Minnesota data also found screening to be more effective in reducing EOGBS than the risk-based approach. In August 2002, the CDC published new guidelines that recommend adoption of a universal screening approach to management of perinatal GBS infections.

Adult↗
PubMed2002

A population-based comparison of strategies to prevent early-onset group B streptococcal disease in neonates.

BACKGROUND: Guidelines issued in 1996 in the United States recommend either screening of pregnant women for group B streptococcal colonization by means of cultures (screening approach) or assessing clinical risk factors (risk-based approach) to identify candidates for intrapartum antibiotic prophylaxis. METHODS: In a multistate retrospective cohort study, we compared the effectiveness of the screening and risk-based approaches in preventing early-onset group B streptococcal disease (in infants less than seven days old). We studied a stratified random sample of the 629,912 live births in 1998 and 1999 in eight geographical areas where there was active surveillance for group B streptococcal infection, including all births in which the neonate had early-onset disease. Women with no documented culture for group B streptococcus were considered to have been cared for according to the risk-based approach. RESULTS: We studied 5144 births, including 312 in which the newborn had early-onset group B streptococcal disease. Antenatal screening was documented for 52 percent of the mothers. The risk of early-onset disease was significantly lower among the infants of screened women than among those in the risk-based group (adjusted relative risk, 0.46; 95 percent confidence interval, 0.36 to 0.60). Because women whose providers had no strategy for prophylaxis may have been misclassified in the risk-based group, we excluded all women with risk factors and adequate time for prophylaxis who did not receive antibiotics. The adjusted relative risk of early-onset disease associated with the screening approach in this secondary analysis was similar--0.48 (95 percent confidence interval, 0.37 to 0.63). CONCLUSIONS: Routine screening for group B streptococcus during pregnancy prevents more cases of early-onset disease than the risk-based approach. Recommendations that endorse both strategies as equivalent warrant reconsideration.

Analysis of Variance↗