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Objective: Human immunodeficiency virus (HIV) infection and AIDS increase the risk of invasive pneumococcal disease (IPD). We evaluated IPD among HIV-infected adults over a 10-year period in the US to identify opportunities for prevention of IPD among HIV-infected adults., Design: IPD and HIV surveillance in seven population-based and laboratory-based Active Bacterial Core surveillance areas., Methods: IPD cases were adults 18-64 years old with pneumococcus isolated from a normally sterile site during 1998-2007. Isolates were serotyped using the Quellung reaction. HIV/AIDS status was determined by medical record review. We calculated incidence of IPD among adults with AIDS using national case-based surveillance data., Results: Of 13 812 IPD cases among 18-64-year-olds, 3236 (23%) occurred among HIV-infected adults (with or without AIDS) and 1313 (10%) occurred among the subset of HIV-infected adults with AIDS. Compared with the period (1998-1999) before childhood 7-valent pneumococcal conjugate vaccine (PCV7) introduction in the US, the overall incidence of IPD among adults with AIDS decreased 25% from 399 to 298 cases per 100 000 by 2007 (P = 0.008). In 2006-2007, 8, 39 and 55% of IPD cases among adults with AIDS were caused by serotypes included in the 7-valent PCV, 13-valent PCV and 23-valent pneumococcal polysaccharide vaccines, respectively., Conclusion: Sustained declines in IPD have occurred among adults with AIDS in the US, but incidence remained high 7 years after PCV7 introduction. More aggressive efforts, including HIV-prevention measures and the use of new PCVs in children and possibly HIV-infected adults, are necessary to further reduce IPD among HIV-infected adults.

Pneumococcal polysaccharide vaccine (PPV-23) has been recommended for HIV-infected adults. We investigated factors that could influence PPV-23 effectiveness against all-cause pneumonia in a longitudinal cohort of 23,255 HIV-infected adults receiving care during 1998--2003. Patients who received PPV-23 had a lower rate of pneumonia (IRR = 0.8; 95% CI: 0.8-0.9) than patients who had never been vaccinated, independent of recent CD4 count, HIV viral load, antiretroviral therapy, and history of pneumonia. However, PPV-23 provided no benefit when patients were vaccinated at HIV viral load > 100,000 copies/ml, irrespective of CD4 count at vaccination. Receipt of PPV-23 was associated with lower incidence of all-cause pneumonia.

Background: The impact of heptavalent pneumococcal conjugate vaccine (PCV7) on transmission of antimicrobial-resistant Streptococcus pneumoniae is an important concern for countries considering PCV7 introduction., Methods: Every winter from 2000 to 2004, as PCV7 was routinely introduced, we obtained nasopharyngeal swabs for pneumococcal culture, serotyping, and susceptibility testing from 150 children aged 3-59 months at each of 3 Anchorage, Alaska clinics. We assessed risk factors for pneumococcal carriage, including vaccination status and antimicrobial use., Results: Between 2000 and 2004, 2250 nasopharyngeal swabs from 2061 infants and children were collected. The proportion of children receiving > or = 1 PCV7 vaccination increased from 0 to 89%, whereas overall pneumococcal carriage remained stable (38% versus 41%, respectively). Among S. pneumoniae carriers, we observed declines in carriage of PCV7 serotypes (from 54% to 10%, P < 0.01) and trimethoprim-sulfamethoxazole nonsusceptible strains (44% to 16%, P < 0.01), but not in PCN-nonsusceptible strains (36% versus 37%). Among PCN-nonsusceptible types, the proportion of serotype 19A strains increased from 10% to 32% (P = 0.0002). Recent beta-lactam use was stable throughout the period (29% overall), whereas trimethoprim-sulfamethoxazole use declined from 6% to 2% (P = 0.02)., Conclusions: PCV7 vaccination in the first 5 years did not affect overall pneumococcal carriage, but was associated with a shift in serotype distribution from PCV7 types to non-PCV7 types. With persistent pressure of some antimicrobials, reductions in carriage of antimicrobial nonsusceptible PCV7 types may be offset by increases in carriage of nonsusceptible non-PCV7 types.

Background: When seven-valent pneumococcal conjugate vaccine was introduced in the USA, many children were vaccinated on schedules that differed from those tested in clinical trials. Our aim was to assess the effectiveness of the vaccine against various pneumococcal serotypes, and to measure the effectiveness of the recommended dose schedule and of catch-up and incomplete schedules., Methods: Invasive disease, defined as isolation of pneumococcus from a sterile site, was identified in children aged 3-59 months through the US Centers for Disease Control and Prevention's Active Bacterial Core surveillance. We tested isolates for serotype and antimicrobial susceptibility. Three controls, matched for age and zip code were selected for each case. We calculated the matched odds ratio for vaccination using conditional logistic regression, controlling for underlying conditions. Vaccine effectiveness was calculated as one minus the adjusted matched odds ratio times 100%., Findings: We enrolled 782 cases and 2512 controls. Effectiveness of one or more doses against vaccine serotypes was 96% (95% CI 93-98) in healthy children and 81% (57-92) in those with coexisting disorders. It was 76% (63-85) against infections that were not susceptible to penicillin. Vaccination prevented disease caused by all seven vaccine serotypes, and by vaccine-related serotype 6A. Several schedules were more protective than no vaccination; three infant doses with a booster were more protective against vaccine-type disease than were three infant doses alone (p=0.0323)., Interpretation: The seven-valent pneumococcal conjugate vaccine prevents invasive disease in both healthy and chronically ill children. The vaccine is effective when used with various non-standard schedules.

Background: The pneumococcal polysaccharide vaccine (PPV) can prevent invasive pneumococcal disease (IPD) in the elderly and those with certain underlying illnesses. However, vaccine uptake remains suboptimal. Identification of missed opportunities for vaccination could guide new strategies for improving uptake. Missed opportunities for vaccination were defined as one or more visits to a hospital, emergency room (ER), or main provider in the 2 years before infection among unvaccinated, adult IPD case-patients with a vaccine indication., Methods: Adults aged 18 years or older with IPD were identified in six Active Bacterial Core surveillance/Emerging Infections Program Network sites during a 1-year period in 2001 to 2003. Using chart review, patient/proxy interview, a main provider questionnaire, and vaccine questionnaires from additional providers, data were collected on demographics, vaccine indications, vaccine status, and recent healthcare encounters., Results: A total of 1878 cases were enrolled, and 83% had a vaccine indication. Of the 1177 cases with a vaccine indication and sufficient information on recent healthcare encounters, 617 (52%) were unvaccinated. Of these, 566 (92%) had one or more opportunities for vaccination, 54% were hospitalized, 58% had ER visits, and 76% visited their main provider in the 2 years before illness. The number of visits to main providers (median = 6) was higher than hospitalizations (median = 1), and ER visits (median = 1)., Conclusions: One or more missed opportunities for vaccination were documented in nearly all unvaccinated IPD case-patients with a vaccine indication. Most visited their main provider multiple times. Implementation of systematic PPV programs in outpatient settings will likely increase pneumococcal vaccine uptake among high-risk adults.

Background: Five of seven serotypes in the pneumococcal conjugate vaccine, introduced for infants in the United States in 2000, are responsible for most penicillin-resistant infections. We examined the effect of this vaccine on invasive disease caused by resistant strains., Methods: We used laboratory-based data from Active Bacterial Core surveillance to measure disease caused by antibiotic-nonsusceptible pneumococci from 1996 through 2004. Cases of invasive disease, defined as disease caused by pneumococci isolated from a normally sterile site, were identified in eight surveillance areas. Isolates underwent serotyping and susceptibility testing., Results: Rates of invasive disease caused by penicillin-nonsusceptible strains and strains not susceptible to multiple antibiotics peaked in 1999 and decreased by 2004, from 6.3 to 2.7 cases per 100,000 (a decline of 57 percent; 95 percent confidence interval, 55 to 58 percent) and from 4.1 to 1.7 cases per 100,000 (a decline of 59 percent; 95 percent confidence interval, 58 to 60 percent), respectively. Among children under two years of age, disease caused by penicillin-nonsusceptible strains decreased from 70.3 to 13.1 cases per 100,000 (a decline of 81 percent; 95 percent confidence interval, 80 to 82 percent). Among persons 65 years of age or older, disease caused by penicillin-nonsusceptible strains decreased from 16.4 to 8.4 cases per 100,000 (a decline of 49 percent). Rates of resistant disease caused by vaccine serotypes fell 87 percent. An increase was seen in disease caused by serotype 19A, a serotype not included in the vaccine (from 2.0 to 8.3 per 100,000 among children under two years of age)., Conclusions: The rate of antibiotic-resistant invasive pneumococcal infections decreased in young children and older persons after the introduction of the conjugate vaccine. There was an increase in infections caused by serotypes not included in the vaccine., (Copyright 2006 Massachusetts Medical Society.)

Background: Adults infected with HIV have high rates of invasive pneumococcal disease. Introduction of pneumococcal conjugate vaccine for children could affect disease among HIV-infected adults., Objective: To compare invasive pneumococcal disease among HIV-infected adults before and after the introduction of a pediatric conjugate vaccine., Design: Active laboratory-based surveillance in an adult population of 10.8 million, including 38,314 living with AIDS., Setting: 7 Active Bacterial Core surveillance areas in the United States., Patients: All surveillance-area residents 18 to 64 years of age with Streptococcus pneumoniae isolated from a sterile site between 1998 and 2003., Measurements: Ratio of the number of cases of invasive pneumococcal disease among HIV-infected adults to the estimated number of adults 18 to 64 years of age living with AIDS; serotype-specific subset analyses; and comparison of periods before and after introduction of conjugate vaccine by using exact tests., Results: Of 8582 cases of invasive pneumococcal disease in adults, 2013 (24%) occurred among persons infected with HIV. Between baseline (1998 to 1999) and 2003, the ratio of invasive pneumococcal disease in HIV-infected adults to the number of adults living with AIDS in the surveillance areas decreased from 1127 to 919 cases per 100 000 AIDS population, a reduction of 19% (P = 0.002). Among HIV-infected adults, the ratio for disease caused by pneumococcal serotypes included in the conjugate vaccine decreased 62% (P < 0.001), although the ratio for disease caused by nonvaccine serotypes increased 44% (P < 0.001)., Limitations: Ratios are proxy measures of incidence rates. The denominator of surveillance-area residents living with HIV infection was not available., Conclusions: Introduction of the pediatric conjugate vaccine was associated with an overall decrease in invasive pneumococcal disease among HIV-infected adults, despite increased disease caused by nonvaccine serotypes.

We evaluated invasive pneumococcal disease (IPD), antimicrobial resistance and nasopharyngeal colonization before and after introduction of pneumococcal conjugate vaccine (PCV7) in Alaska Natives (AN), a population with high IPD rates. We obtained IPD rates from population-based surveillance. Colonization was determined from annual surveys among rural AN of all ages and from urban children. After vaccine introduction, vaccine-type IPD rates declined by 91% among AN children <2 years, by 80% among non-Natives <2 years, and by 40% for adults of all races (P<0.001 each). IPD decreased for isolates resistant to penicillin, erythromycin and cotrimoxazole (P<0.001 each). Vaccine-type colonization decreased among rural and urban children <5 years and among rural adults (P<0.001 each). PCV7 vaccine has eliminated a longstanding disparity of vaccine-type IPD for AN children. Decreased vaccine-type colonization and IPD in adults demonstrate indirect vaccine effects.

A study of children was conducted in 3 Central Asian Republics. Approximately half of the Streptococcus pneumoniae isolates were serotypes included in available vaccine formulations. Approximately 6% of children carried Haemophilus influenzae type b (Hib). Using pneumococcal and Hib conjugate vaccines may decrease illness in the Central Asian Republics.

High rates of preventable diseases such as pneumococcal disease occur among the Navajo despite their universal health insurance through the Indian Health Service. The objective of this study was to determine the proportion of Navajo adults vaccinated with pneumococcal polysaccharide vaccine and to examine key features of vaccination programs of the Navajo Indian Health Service. For this cross-sectional study, medical charts of Navajo patients with vaccine indications were randomly selected and reviewed to determine who had been vaccinated as of January 1, 1999. Among 480 Navajo>or=65 years old, 73% were vaccinated (95% confidence interval [CI]: 69%-77%). Among 111 Navajo 18-64 years old with vaccine indications, 54% were vaccinated (95% CI: 45% -63%). Vaccination programs utilized extensive public health nursing, home visits, standing orders, and "express lane" clinics. In spite of excellent delivery systems and universal healthcare, the proportion of Navajo persons vaccinated was still below the goals for Healthy People 2010 of having 90% of persons>or=65 years old vaccinated and 60% of high-risk persons 18-64 years old vaccinated.

Background: Streptococcus pneumoniae is a leading cause of invasive bacterial disease and pneumonia among children. Antimicrobial resistance among pneumococci has increased in recent years and complicates treatment. The introduction of heptavalent pneumococcal conjugate vaccine (PCV7) could reduce acquisition of antimicrobial-resistant pneumococci., Methods: We obtained 1350 nasopharyngeal swabs for culture from 1275 children aged 3-59 months presenting at 3 clinics in Anchorage, Alaska, during the winters of 2000, 2001, and 2002, as PCV7 was being introduced into the routine immunization schedule. We recorded the frequency of use of antibiotics as well as the dates of doses of PCV7 for enrolled children. We used multivariate logistic regression modeling to identify independent risk factors for overall carriage of pneumococci and carriage of PCV7-type pneumococci, cotrimoxazole-nonsusceptible (COT-NS) pneumococci, or penicillin-nonsusceptible (PCN-NS) pneumococci., Results: The proportion of children who were up-to-date for age, with respect to PCV7 vaccination, increased from 0% in 2000 to 55% in 2002. Carriage of PCV7-type pneumococci decreased by 43% (P<.0001). Risk of carriage of PCV7-type pneumococci was lower in 2002 than in 2000, independent of vaccination status, suggesting an indirect effect of vaccination. Carriage of COT-NS, but not PCN-NS, pneumococci also decreased (38%; P=.02), not only among vaccinated children but also among unvaccinated children without recent use of antibiotics., Conclusions: Introduction of PCV7 into the routine infant immunization schedule in a community with a high prevalence of antimicrobial-resistant pneumococci appears to reduce transmission of PCV7 vaccine serotypes and COT-NS pneumococci but has no impact on overall carriage of pneumococci or carriage of PCN-NS pneumococci.

Invasive pneumococcal disease occurs 2-3-fold more often among Navajo adults than among adults in the general United States population. The objective of this observational study was to determine the effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPV23) among Navajo adults. Active surveillance identified cases of invasive pneumococcal disease during 1996-1997. Three control patients per case patient were matched according to underlying medical conditions, sex, age, and location of medical care. Effectiveness was calculated by regression analysis of case-control sets and by indirect cohort methodology. Diabetes and alcoholism occurred in 41% and 43% of 108 case patients, respectively; 62% of case patients and 64% of control patients were immunized. Overall vaccine effectiveness was 26% (95% confidence interval [CI], -29% to 58%); 15% (95% CI, -116% to 67%) for patients with diabetes and -5% (95% CI, -141% to 54%) for patients with alcoholism. Overall vaccine effectiveness, as determined by use of the indirect cohort methodology, was 35% (95% CI, -33% to 69%). PPV23 was not significantly effective among Navajo adults and may be inadequate to prevent serious pneumococcal disease in this population.

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., (Copyright 2003 Massachusetts Medical Society)

We compared the hypothetical effects of the 23-valent polysaccharide pneumococcal vaccine with new vaccines on preventing invasive and noninvasive pneumococcal disease in persons >or=65 years. We estimated how much disease would occur if no polysaccharide vaccine were in use and used this baseline to compare the polysaccharide, a 7-valent conjugate vaccine, and hypothetical common antigen vaccine. The polysaccharide, conjugate, and common antigen vaccines prevented 10.6, 10.7, and 17.7% of invasive disease and 4.3, 5.6, and 10.0% of pneumonia, respectively. Superior effectiveness of new vaccines was dependent upon a presumed longer duration of protection than the 23V-PPV and effectiveness against noninvasive pneumonia. Our results suggest that new vaccines could improve disease prevention.

Objective To describe and compare serotype distribution and antibiotic susceptibility of invasive and nasopharyngeal isolates of Streptococcus pneumoniae from children in rural Mozambique. Methods From August 2002 to July 2003, we prospectively obtained invasive pneumococcal isolates from children <15 years of age admitted to the paediatric ward of Manhiça District Hospital. During a cross-sectional study of children <5 years of age with mild illnesses, attending the outpatient department of the hospital in March and April 2003, we collected nasopharyngeal isolates. Serotypes and antibiotic susceptibilities were determined using standardized methods. Results The two most common pneumococcal serotypes among invasive isolates were types 1 (40% of 88 isolates serotyped) and 5 (10%), but these types were rare among nasopharyngeal isolates. Compared with invasive isolates, nasopharyngeal isolates were more likely to be serotypes in the licensed seven-valent conjugate vaccine (49% vs. 20%, P < 0.01), to have intermediate-level penicillin resistance (52% vs. 14%, P < 0.01) and to be non-susceptible to trimethoprim–sulfamethoxazole (61% vs. 45%, P < 0.01). Recent receipt of antibiotics or sulfadoxine/pyrimethamine were associated with carriage of antibiotic non-susceptible isolates. Conclusions These data indicate that a pneumococcal conjugate vaccine containing serotypes 1 and 5 could substantially reduce pneumococcal invasive disease among young children in rural Mozambique. Carriage surveys can overestimate potential coverage of the seven-valent pneumococcal conjugate vaccine in settings where serotypes 1 and 5 predominate. [ABSTRACT FROM AUTHOR]

Background. Pneumococcal disease is most prevalent among young children and elderly adults. We explored whether similarities exist in the serotypes that cause disease in these 2 high-risk groups. Methods. With use of US population-based data from 1998-1999 (before the introduction of the 7-valent pneumococcal conjugate vaccine [PCV7] as routine immunization for infants) from the Centers for Disease Control and Prevention's Active Bacterial Core surveillance, we evaluated whether the rate of invasive pneumococcal disease caused by the pediatric serotypes (6B, 9V, 14, 19F, and 23F) increased among elderly persons. We adjusted for potential confounders in multivariable logistic regression. Results. We analyzed 2987 pneumococcal isolates recovered from adults. The risk of infection with pediatric serotypes increased from 32.5% in 35-49-year-old persons to 51.2% in ⩾85-year-old persons (P < .001). Compared with 35-49-year-old persons, the risk of infection with pediatric serotypes was significantly elevated among 65- 74-year-old persons (relative risk [RR], 1.68; 95% confidence interval [I], 1.29-2.20) and increased progressively among persons aged 75-84 years (RR, 1.82; 95% CI, 1.41-2.36) and ⩾85 years (RR, 2.29; 95% CI, 1.72-3.05), with adjustment for sex, race, geographic location, underlying illness, and penicillin resistance. The rate of penicillin resistance was also elevated in the elderly population but was not significant after adjustment for serotype and race. Conclusions. The increased proportion of severe pneumococcal disease caused by pediatric serotypes in the elderly population might indicate opportunities for prevention with use of PCV7. [ABSTRACT FROM AUTHOR]

Presents a study to assess pneumococcal disease burden in the United States, estimate the potential impact of new vaccines, and identify gaps in vaccine recommendations. Design and setting; Patients; Main outcome measures; Results; Conclusion that young children, elderly persons, and black persons of all ages are disproportionately affected by invasive pneumococcal disease; Current Advisory Committee on Immunization Practices (ACIP) recommendations.

Background: The rate of bacterial meningitis declined by 55% in the United States in the early 1990s, when the Haemophilus influenzae type b (Hib) conjugate vaccine for infants was introduced. More recent prevention measures such as the pneumococcal conjugate vaccine and universal screening of pregnant women for group B streptococcus (GBS) have further changed the epidemiology of bacterial meningitis. Methods: We analyzed data on cases of bacterial meningitis reported among residents in eight surveillance areas of the Emerging Infections Programs Network, consisting of approximately 17.4 million persons, during 1998–2007. We defined bacterial meningitis as the presence of H. influenzae, Streptococcus pneumoniae, GBS, Listeria monocytogenes, or Neisseria meningitidis in cerebrospinal fluid or other normally sterile site in association with a clinical diagnosis of meningitis. Results: We identified 3188 patients with bacterial meningitis; of 3155 patients for whom outcome data were available, 466 (14.8%) died. The incidence of meningitis changed by −31% (95% confidence interval [CI], −33 to −29) during the surveillance period, from 2.00 cases per 100,000 population (95% CI, 1.85 to 2.15) in 1998–1999 to 1.38 cases per 100,000 population (95% CI 1.27 to 1.50) in 2006–2007. The median age of patients increased from 30.3 years in 1998–1999 to 41.9 years in 2006–2007 (P<0.001 by the Wilcoxon rank-sum test). The case fatality rate did not change significantly: it was 15.7% in 1998–1999 and 14.3% in 2006–2007 (P=0.50). Of the 1670 cases reported during 2003–2007, S. pneumoniae was the predominant infective species (58.0%), followed by GBS (18.1%), N. meningitidis (13.9%), H. influenzae (6.7%), and L. monocytogenes (3.4%). An estimated 4100 cases and 500 deaths from bacterial meningitis occurred annually in the United States during 2003–2007. Conclusions: The rates of bacterial meningitis have decreased since 1998, but the disease still often results in death. With the success of pneumococcal and Hib conjugate vaccines in reducing the risk of meningitis among young children, the burden of bacterial meningitis is now borne more by older adults. (Funded by the Emerging Infections Programs, Centers for Disease Control and Prevention.) [ABSTRACT FROM PUBLISHER]