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The heptavalent pneumococcal conjugate vaccine (PCV7) has been shown to reduce the incidence of acute otitis media (AOM) caused by Streptococcus pneumoniae by 34% and reduces the overall incidence of AOM by 6% to 8%. More recent studies have shown increases in the proportion of Haemophilus influenzae and Moraxella catarrhalis in the middle-ear fluid of PCV7-immunized children. There has been no report on the effect of PCV7 on all 3 bacterial pathogens combined, either in the middle-ear fluid or nasopharynx of individual children with AOM. We investigated the impact of PCV7 on nasopharyngeal colonization with bacterial pathogens during AOM in the pre-PCV7 and post-PCV7 vaccination eras. Four hundred seventeen children (6 months to 4 years of age) were enrolled onto AOM studies between September 1995 and December 2004. Of these, 200 were enrolled before the vaccine use (historical controls), and 217 were enrolled after the initiation of PCV7 vaccination (101 were underimmunized, and 116 were immunized). Although the nasopharyngeal colonization rate for S pneumoniae was not different between the 3 groups, a significantly higher proportion of PCV7-immunized children with AOM were colonized with M catarrhalis. Overall, the mean number of pathogenic bacteria types isolated from immunized children (1.7) was significantly higher than in controls (1.4). The increase in bacterial colonization of the nasopharynx during AOM could be associated with an increase in AOM pathogens and theoretically can predispose PCV7-immunized children with AOM to a higher rate of antibiotic treatment failure or recurrent AOM., Key Words: acute otitis media, nasopharyngeal bacterial colonization, pneumococcal conjugate vaccine Abbreviations: AOM, acute otitis media; PCVT, heptavalent pneumococcal conjugate vaccine; MEF, middle-ear fluid; UTMB, University of Texas Medical Branch; [...]

Seven-valent pneumococcal conjugate vaccine (PCV7) was licensed in February 2000. In June 2000, the Advisory Committee on Immunization Practices and the American Academy of Pediatrics recommended the universal administration of pneumococcal conjugate vaccine for all children 23 months of age and younger and for children 24 to 59 months of age who are at high risk for serious pneumococcal disease. Since then, > 23 million doses have been administered in the United States. Postlicensure surveillance of invasive pneumococcal disease (IPD) in the United States from the Active Bacterial Core Surveillance program at the Centers for Disease Control and Prevention and the Northern California Kaiser Permanente Vaccine Study Center has reported a decline in IPD and in pneumococcal disease incidence as a result of vaccine serotypes, respectively. During this period, issues critical to the long-term success of PCV7 have become more relevant: Will PCV7 be as effective in groups of children who are at high risk for IPD as in healthy children? Will nonvaccine types replace vaccine serotypes in the nasopharynx and in disease? Why are the results of the clinical trials different for IPD and for acute otitis media? How many doses of PCV7 and what concentrations of antibody are necessary for protection? Will universal administration of PCV7 to children younger than 2 years reduce antimicrobial drug resistance and alter prescribing patterns of physicians for febrile infants? Have there been unanticipated adverse events or benefits observed? The purpose of this report is to review the current data available to address these questions and to identify gaps that will require additional knowledge to determine the ultimate value of pneumococcal conjugate vaccines in reducing the burden of pneumococcal disease in infants and children. Pediatrics 2002;110:805-814; pneumococcal disease, pneumococcal vaccine, conjugate vaccine, carriage, serotypes., ABBREVIATIONS. PCV, pneumococcal conjugate vaccine; IPD, invasive pneumococcal disease; NCKP, Northern California Kaiser Permanente; HIV, human immunodeficiency virus; NP, nasopharyngeal; PPV, pneumococcal polysaccharide vaccine; ELISA, enzyme-linked immunosorbent assay; OPA, opsonophagocytic [...]

Objective. Although invasive pneumococcal disease is infrequent in cystic fibrosis (CF), it is recommended that all patients with CF receive pneumococcal immunization. As part of a comprehensive program to immunize our clinic population, we obtained preimmunization anti-pneumococcal antibody levels. We hypothesized that the percentage of CF patients without protective levels of anti-pneumococcal antibody levels would be high, as they are exposed to frequent antibiotic therapy that may eradicate organisms before generation of an antibody response. Methods. An observational study of 100 patients with CF, aged 1 to 39 years, was conducted in a regional CF center. Preimmunization anti-pneumococcal antibody levels against 6 serotypes were measured by enzyme-linked immunosorbent assay. Protective antibody levels were defined as [is greater than] 200 ng/mL. Results. A majority of CF patients--61% to 100%, depending on age and serotype--had protective levels of pneumococcal antibody. There was a significant positive correlation between antibody level and age for 5 of the 6 serotypes tested. Conclusions. In contradistinction to our hypothesis, the majority of CF patients have protective preimmunization anti-pneumococcal antibody levels. However, a significant proportion--between 17% and 39%, depending on the serotype--did not exhibit adequate levels. Therefore, we concur with current recommendations for pneumococcal immunization in CF. Pediatrics 2001;107(4). URL: http://www.pediatrics.org/cgi/content/ full/107/4/e62; cystic fibrosis, Streptococcus pneumoniae, immunization, ELISA.

Objectives. The optimal practice management of highly febrile 3- to 36-month-old children without a focal source has been controversial. The recent release of a conjugate pneumococcal vaccine may reduce the rate of occult bacteremia and alter the utility of empiric testing and treatment. The objective of this study was to determine the cost-effectiveness of 6 different management strategies of febrile 3- to 36-month-old children at current and declining rates of occult pneumococcal bacteremia. Methods. A cost-effectiveness (CE) analysis was performed to compare the strategies of "no work-up," "clinical judgment," "blood culture," "blood culture + treatment," "complete blood count (CBC) + selective blood culture and treatment," and "CBC and blood culture + selective treatment." A hypothetical cohort of 100 000 children who were 3 to 36 months of age and had a fever of [is greater than or equal to] 39 [degrees] C and no source of infection was modeled for each strategy. Our main outcome measures were cases of meningitis prevented, life-years saved compared with "no work-up," total cost (1999 dollars), and incremental CE ratios. Results. When compared with "no work-up," the strategy of "CBC + selective blood culture and treatment" using a white blood cell (WBC) cutoff of 15 x [10.sup.9]/L prevents 48 cases of meningitis, saves 86 life-years per 100 000 patients, and is less costly at the current rate of bacteremia (1.5%). Using the strategy of "CBC + selective blood culture and treatment" with a lower WBC cutoff of 10 x [10.sup.9]/L costs an additional $72 300 per life-year saved. If the rate of bacteremia declines to 0.5%, then the incremental CE ratio of "clinical judgment" compared with "no work-up" is $38 000 per life-year saved; however, strategies that include empiric testing or treatment result in CE ratios greater than $300 000 per life-year saved. Conclusions. "CBC + selective blood culture and treatment" using a WBC cutoff of 15 x [10.sup.9]/L is cost-effective at the current rate of pneumococcal bacteremia. If the rate of occult bacteremia falls below 0.5% with widespread use of the conjugate pneumococcal vaccine, then strategies that use empiric testing and treatment should be eliminated. Pediatrics 2001;108:835-844; fever, occult bacteremia, conjugate pneumococcal vaccine, cost-effectiveness analysis., ABBREVIATIONS. CBC, complete blood count; WBC, white blood count; CE, cost-effectiveness; YOS, Yale Observation Score. Physicians frequently evaluate and treat young, highly febrile children in the setting of the office [...]

ABBREVIATIONS. AAP, American Academy of Pediatrics; ACIP, Advisory Committee on Immunization Practices; CDC, Centers for Disease Control and Prevention; AAFP, American Academy of Family Physicians; PCV, pneumococcal conjugate vaccine; FDA, [...]

Pneumococcal infections are the most common invasive bacterial infections in children in the United States. The incidence of invasive pneumococcal infections peaks in children younger than 2 years, reaching rates of 228/100 000 in children 6 to 12 months old. Children with functional or anatomic asplenia (including sickle cell disease [SCD]) and children with human immunodeficiency virus infection have pneumococcal infection rates 20- to 100-fold higher than those of healthy children during the first 5 years of life. Others at high risk of pneumococcal infections include children with congenital immunodeficiency; chronic cardiopulmonary disease; children receiving immunosuppressive chemotherapy; children with immunosuppressive neoplastic diseases; children with chronic renal insufficiency, including nephrotic syndrome; children with diabetes; and children with cerebrospinal fluid leaks. Children of Native American (American Indian and Alaska Native) or African American descent also have higher rates of invasive pneumococcal disease. Outbreaks of pneumococcal infection have occurred with increased frequency in children attending out-of-home care. Among these children, nasopharyngeal colonization rates of 60% have been observed, along with pneumococci resistant to multiple antibiotics. The administration of antibiotics to children involved in outbreaks of pneumococcal disease has had an inconsistent effect on nasopharyngeal carriage. In contrast, continuous penicillin prophylaxis in children younger than 5 years with SCD has been successful in reducing rates of pneumococcal disease by 84%. Pneumococcal polysaccharide vaccines have been recommended since 1985 for children older than 2 years who are at high risk of invasive disease, but these vaccines were not recommended for younger children and infants because of poor antibody response before 2 years of age. In contrast, pneumococcal conjugate vaccines (Prevnar) induce proposed protective antibody responses ([is greater than] .15 [micro]g/ mL) in [is greater than] 90% of infants after 3 doses given at 2, 4, and 6 months of age. After priming doses, significant booster responses (ie, immunologic memory) are apparent when additional doses are given at 12 to 15 months of age. In efficacy trials, infant immunization with Prevnar decreased invasive infections by [is greater than] 93% and consolidative pneumonia by 73%, and it was associated with a 7% decrease in otitis media and a 20% decrease in tympanostomy tube placement. Adverse events after the administration of Prevnar have been limited to areas of local swelling or erythema of 1 to 2 cm and some increase in the incidence of postimmunization fever when it is given with other childhood vaccines. Based on data in phase 3 efficacy and safety trials, the US Food and Drug Administration has provided an indication for the use of Prevnar in children younger than 24 months., ABBREVIATIONS. AOM, acute otitis media; SCD, sickle cell disease; HIV, human immunodeficiency virus; OR, odds ratio; CI, confidence interval; NP, nasopharyngeal; PCV7, heptavalent pneumococcal [CRM.sub.197] conjugate vaccine; DTaP, diphtheria and [...]

Heptavalent pneumococcal conjugate vaccine (PCV7) is recommended for universal use in children 23 months and younger, to be given concurrently with other recommended childhood vaccines at 2, 4, 6, and 12 to 15 months of age. For children 7 to 23 months old who have not received previous doses of PCV7, administration of a reduced number of doses is recommended. Two doses of PCV7 are recommended for children 24 to 59 months old at high risk of invasive pneumococcal infection--including children with functional, anatomic, or congenital asplenia; infection with human immunodeficiency virus; and other predisposing conditions--who have not been immunized previously with PCV7. Recommendations have been made for use of 23-valent pneumococcal polysaccharide (23PS) vaccine in high-risk children to expand serotype coverage. High-risk children should be given vaccines at the earliest possible opportunity. Use of antibiotic prophylaxis in children younger than 5 years with functional or anatomic asplenia, including children with sickle cell disease, continues to be recommended. Children who have not experienced invasive pneumococcal infection and have received recommended pneumococcal immunizations may discontinue prophylaxis after 5 years of age. The safety and efficacy of PCV7 and 23PS in children 24 months or older at moderate or lower risk of invasive pneumococcal infection remain under investigation. Current US Food and Drug Administration indications are for administration of PCV7 only to children younger than 24 months. Data are insufficient to recommend routine administration of PCV7 for children at moderate risk of pneumococcal invasive infection, including all children 24 to 35 months old, children 36 to 59 months old who attend out-of-home care, and children 36 to 59 months old who are of Native American (American Indian and Alaska Native) or African American descent. However, all children 24 to 59 months old, regardless of whether they are at low or moderate risk, may benefit from the administration of pneumococcal immunizations. Therefore, a single dose of PCV7 or 23PS vaccine may be given to children 24 months or older. The 23PS is an acceptable alternative to PCV7, although an enhanced immune response and probable reduction of nasopharyngeal carriage favor the use of PCV7 whenever possible., ABBREVIATIONS. PCV7, heptavalent pneumococcal conjugate vaccine; 23PS, 23-valent pneumococcal polysaccharide; SCD, sickle cell disease; DTaP, diphtheria and tetanus toxoids and acellular pertussis; HbOC, Haemophilus influenzae type b conjugate vaccine; HIV, [...]

Objectives. Pneumococcal conjugate vaccine (PCV) was first licensed for routine administration to young children in February 2000. The objective of this study was to assess physician perspectives about the use of PCV, to ascertain which children were being given the vaccine soon after licensure, and to determine how the addition of PCV to the schedule of recommended childhood vaccines may affect the timing of other vaccinations. Methods. A 30-item survey containing questions about the use of PCV was sent to all pediatricians and family physicians who provide primary care to young children in Monroe County (Rochester, NY) and Davidson County (Nashville, TN) in October 2000. As many as 3 subsequent mailings were sent to nonresponders. Descriptive and [chi square] statistical analyses and logistic regression were used to evaluate the responses. Results. Response rates were 82% in Rochester and 78% in Nashville. Eighty-two percent of responding physicians, including 92% of pediatricians and 55% of family physicians, indicated that they were giving PCV to their patients at the time of the survey. Sixty percent noted that an initial lack of insurance reimbursement for the cost of the vaccine caused them to delay introducing PCV. Fifty-one percent delayed initially offering the vaccine to any of their patients because the Vaccines for Children (VFC) program did not begin to offer PCV until several months later. The vast majority routinely vaccinated healthy children who are younger than 2 years as well as older children who had defined chronic medical conditions that put them at high risk of invasive pneumococcal disease. Fewer than 15% were recalling patients for PCV, with most recall efforts focused on patients who had chronic medical conditions. When discussing PCV with parents, 78% of physicians primarily emphasized the vaccine's potential to decrease the risk of sepsis and/or meningitis, whereas smaller percentages primarily emphasized the vaccine's potential to decrease the risk of pneumonia or ear infections. Approximately 20% of physicians who gave PCV delayed other vaccinations (primarily varicella vaccine, hepatitis B vaccine, or polio vaccine) because of concern about administering 4 or more vaccines simultaneously. Similarly, 40% of physicians indicated that they considered PCV to be more important than varicella vaccine or hepatitis B vaccine, whereas 26% percent considered PCV to be more important than polio vaccine. Conclusions. PCV has been widely accepted by physicians in both Rochester and Nashville. However, many physicians delayed introducing the vaccine for reasons that were ultimately related to financial considerations. For privately insured patients, delays were related to when coverage for PCV was added to benefit packages. For patients who receive publicly purchased vaccine via the VFC program, delays were related to availability of the vaccine through the VFC program. In addition, after the introduction of PCV, some physicians began delaying the administration of other vaccines because of the need to give multiple vaccinations simultaneously. Although lack of insurance or VFC coverage and concerns about multiple simultaneous injections may somewhat delay the initial use of newly recommended vaccines, physicians rapidly begin to provide new vaccines that they believe to be beneficial once those vaccines are incorporated into existing payment mechanisms. Pediatrics 2002;110(6). URL: http://www.pediatrics.org/ cgi/content/full/110/6/e68; Pneumococcus, vaccine, vaccination, immunization.