Prevalence of reovirus-specific antibodies in young children in Nashville, Tennessee.

Although reovirus infections are thought to be common in adults, there have been few assessments of the seroprevalence of reovirus in young children. We developed an indirect enzyme-linked immunosorbent assay to measure levels of total antireovirus immunoglobulin A, G, and M in serum specimens collected from otherwise healthy infants and children (1 month to 5 years of age) in Nashville, Tennessee. Of the 272 serum specimens evaluated, 64 (23.

Differential regulation of granzyme and perforin in effector and memory T cells following smallpox immunization.

Primary immunization of healthy adults with vaccinia virus induces a local vesicle or "take" in the majority of vaccinees that previously has been shown to correlate with protection against smallpox. However, the immunologic mechanisms underlying this protective response in humans are not well characterized. We have studied human CD8+ T cells for the expression patterns of phenotypic markers and cytolytic effector molecules before and after primary smallpox immunization using nine-color polychromatic flow cytometry.

Seasonality of invasive pneumococcal disease: temporal relation to documented influenza and respiratory syncytial viral circulation.

Background: Seasonal fluctuation in the incidence of invasive pneumococcal disease has been attributed to winter virus exposure (e.g., influenza and respiratory syncytial virus [RSV]).

Smallpox vaccination does not elevate systemic levels of prothrombotic proteins associated with ischemic cardiac events.

Background: During the recent smallpox vaccination campaigns, ischemic cardiac complications were observed after vaccination. To examine a possible association between the smallpox vaccine and postvaccination ischemic events, we investigated alterations in levels of prothrombotic proteins (plasminogen activator inhibitor type 1 [PAI-1] and soluble CD40 ligand [sCD40L]) in recently vaccinated individuals.

Methods: Vaccinia-naive (cohort N; aged 18-32 years) and vaccinia-experienced (cohort E; aged 33-49 years) healthy adults were vaccinated with a 1 : 5 dilution of the Aventis Pasteur smallpox vaccine.

Establishment of diagnostic cutoff points for levels of serum antibodies to pertussis toxin, filamentous hemagglutinin, and fimbriae in adolescents and adults in the United States.

Numerous reports have documented that serologic methods are much more sensitive than culture for the diagnosis of pertussis in adolescents and adults. However, a standardized serologic test for pertussis is not routinely available to most clinicians, and the serologic test levels or cutoff points correlated with diseases have not been determined. The goal of the present study was to examine the distribution of immunoglobulin G (IgG) levels against three Bordetella pertussis antigens (pertussis toxin [PT], filamentous hemagglutinin [FHA], and fimbria types 2 and 3 [FIM]) and to determine population-based antibody levels for the purpose of establishing such diagnostic cutoff points.

Tolerance to vancomycin in pneumococci: detection with a molecular marker and assessment of clinical impact.

Background: Vancomycin is often added to therapy for meningitis caused by Streptococcus pneumoniae. Tolerant bacteria without classic resistance that escape killing by multiple antibiotics have been reported sporadically. We determined the prevalence of tolerance to vancomycin in pneumococci and its effect on the outcome of meningitis.

Reduction in high rates of antibiotic-nonsusceptible invasive pneumococcal disease in tennessee after introduction of the pneumococcal conjugate vaccine.

Background: Invasive pneumococcal disease (IPD) is a burgeoning problem, with rates of antibiotic-nonsusceptible IPD, in particular, increasing during the past decade. One measure to combat IPD is vaccination with the recently introduced 7-valent pneumococcal conjugate vaccine (PCV).

Methods: To evaluate the effects of the introduction of PCV in 2000 on the epidemiology of antibiotic-nonsusceptible IPD, a database of IPD cases from January 1995 through December 2002 identified through active surveillance in 5 Tennessee counties was examined.

Vaccination success rate and reaction profile with diluted and undiluted smallpox vaccine: a randomized controlled trial.

Context: Additional smallpox vaccine doses are needed to augment current US national stockpile. Aventis Pasteur smallpox vaccine (APSV), initially manufactured in the 1950s from the New York Board of Health vaccinia strain in a frozen preparation, appears as effective as lyophilized vaccine but the effectiveness of diluted doses of APSV is unclear.

Objective: To compare the vaccination success rate and the reaction profile of various APSV dilutions.

Population-based impact of pneumococcal conjugate vaccine in young children.

Objective: To determine the population impact of pneumococcal conjugate vaccine (PCV) on pneumococcal-related diseases, including pneumonia and otitis media.

Methods: Using administrative data from Tennessee Medicaid and 3 commercial insurance plans in upstate New York, we measured annual rates of medical visits for pneumococcal-related diseases (pneumococcal and nonspecific pneumonia and invasive disease; otitis media) and pneumococcal-unrelated diseases (other acute respiratory illnesses). Disease rates before (1995-2000 in Tennessee; 1998-2000 in New York) and after (2000-2002) PCV licensure were calculated for children aged <2 years (eligible for PCV) and those 3 to 5 years (not routinely given PCV).

Elimination of racial differences in invasive pneumococcal disease in young children after introduction of the conjugate pneumococcal vaccine.

Background: Racial differences in the epidemiology of invasive pneumococcal disease (IPD) have been widely recognized, but the impact of conjugate pneumococcal vaccine (PCV) introduction in 2000 on these differences has not been extensively studied.

Methods: IPD episodes in 5 Tennessee counties from January 1995 through December 2002 were collected prospectively using the Centers for Disease Control and Prevention's Active Bacterial Core Surveillance system (ABCs). Trained nurses collected clinical data, and antibiotic susceptibility testing was performed on available isolates.

Immune responses and antibody decay after immunization of adolescents and adults with an acellular pertussis vaccine: the APERT Study.

As part of a prospective acellular pertussis (ACP) vaccine efficacy trial, 5 serum samples were obtained, over an 18-month period, from 101 ACP-vaccine recipients and 99 control subjects, to assess ACP antibody response and decay. Immunoglobulin (Ig) G and IgA antibodies to pertussis toxin (PT), filamentous hemagglutinin (FHA), pertactin (PRN), and fimbriae 2/3 (FIM) were measured by enzyme-linked immunosorbant assay, and titers of agglutinin were determined. Of the subjects, 16%-19% had preimmunization values of antibodies to PT that were above the assay's limit of quantitation (LOQ); in contrast, 36%-63% of the subjects had preimmunization values of antibodies to FHA, PRN, or FIM that were above the LOQ.

Prevalence of pertussis antibodies in maternal delivery, cord, and infant serum.

Background: Passively acquired maternal antibodies protect infants from many pathogens. With increasing reports of infant pertussis, we evaluated pertussis antibodies in maternal-infant paired sera from 1999-2000.

Methods: Antibodies to pertussis toxin (PT), filamentous hemagglutinin (FHA), and fimbrial proteins (FIM) were measured by validated IgG-specific enzyme-linked immunosorbant assay (ELISA) in 64 maternal-umbilical cord serum pairs and in 61 of 64 infant sera.

Human metapneumovirus infection among children hospitalized with acute respiratory illness.

Recent studies have associated human metapneu-movirus (HMPV) infection in children with respiratory disease of similar severity as respiratory syncytial virus (RSV) infection. We studied 668 banked swab specimens (one per admission) collected from a population-based, prospective study of acute respiratory illness among inpatient children from two U.S.

Population-based surveillance for hospitalizations associated with respiratory syncytial virus, influenza virus, and parainfluenza viruses among young children.

Objective: Respiratory syncytial virus (RSV), influenza virus, and parainfluenza viruses (PIV) cause significant morbidity in young children. Although only influenza virus infection and illness is currently vaccine-preventable, vaccines are under development for RSV and PIV. We established a prospective, active population-based surveillance network to provide precise estimates of hospitalization rates for viral acute respiratory illness (ARI) in young children and to measure the potential impact of enhanced vaccine usage on these rates.

Adverse events after smallpox immunizations are associated with alterations in systemic cytokine levels.

The immunization of healthy adults with vaccinia virus (VV) induces a protective response against smallpox in most individuals but is also reactogenic in a significant number of vaccinees. The immunological mechanisms underlying the protective response or adverse events in humans are not well defined. Although cytokines contribute to antiviral immunity and, in some cases, cause systemic adverse effects, their role in the human response to VV is unknown.

Evaluation of anatomic changes in young children with natural rotavirus infection: is intussusception biologically plausible?

Background: Several studies have shown an association between vaccination with the rotavirus vaccine and the development of intussusception. We evaluated the plausibility of a causal association between natural rotavirus infection and intussusception.

Methods: We performed ultrasound measurements, in infants with confirmed rotavirus infection and in healthy control subjects, of the ileum wall thickness and mesenteric lymph nodes, at enrollment and 1 month later.

Surveillance of childhood influenza virus infection: what is the best diagnostic method to use for archival samples?

Despite the clinical importance of influenza virus in pediatric respiratory infections, the optimal set of diagnostic tests to use when conducting studies using archival samples is not clear. In this study, we compared diagnostic tests for influenza virus in 75 children younger than 5 years of age who presented with symptomatic respiratory infection during one of four influenza seasons, had negative viral cultures for other respiratory pathogens, and had both an archival nasal aspirate obtained at the time of illness and serology spanning that influenza season. For all eligible children, we compared the results of viral culture performed at the time of collection with serology and PCR of archival nasal aspirates.

Superiority of reverse-transcription polymerase chain reaction to conventional viral culture in the diagnosis of acute respiratory tract infections in children.

We compared the rates of detection of respiratory viruses by reverse-transcription polymerase chain reaction (RT-PCR) and by conventional viral culture in 668 combined nasal and throat samples from a prospective, multicenter, population-based study of acute respiratory tract infections among hospitalized children aged <5 years. RT-PCR increased the yield of viral identification by 2-fold, compared with that of culture alone. The increased sensitivity of viral detection by RT-PCR will yield better estimates of the population burden of viral respiratory infections.

Risk of vaccinia transfer to the hands of vaccinated persons after smallpox immunization.

Transmission of vaccinia virus after smallpox vaccination is a concern. We conducted a prospective examination of the protection afforded by vaccination-site bandages in recently vaccinated individuals. After smallpox vaccination, inoculation sites were covered with 2 occlusive dressings.

Differences in antibiotic prescribing patterns for children younger than five years in the three major outpatient settings.

Objectives: To perform a comprehensive analysis of the use of antibiotics in three major sites for outpatient care: private office-based clinics, emergency departments (ED), and hospital-based clinics.

Study Design: Data from the National Ambulatory Medical Care Survey (NAMCS) and National Hospital Ambulatory Medical Care Survey (NHAMCS) were used to determine visit rates and antibiotic prescribing patterns for the three major outpatient care settings from 1994 to 2000 for children <5 years of age.

Results: Antibiotic prescription rates declined from 1405 to 1088 per 1000 children over the study years (P=.

Immune responses to influenza immunization in children receiving maintenance chemotherapy for acute lymphoblastic leukemia.

Purpose: To compare the immune responses to influenza vaccine in children with acute lymphoblastic leukemia (ALL) receiving maintenance chemotherapy with those in healthy children.

Methods: Hemagglutinin-inhibition (HAI) antibody titers were determined before and after influenza vaccination in children with ALL and healthy controls. Immune responses were measured as geometric mean titers (GMT) and 4-fold rises in HAI titers.

Human metapneumovirus and lower respiratory tract disease in otherwise healthy infants and children.

Background: We sought to determine the role of human metapneumovirus in lower respiratory tract illness in previously healthy infants and children.

Methods: We tested nasal-wash specimens, obtained over a 25-year period from otherwise healthy children presenting with acute respiratory tract illness, for human metapneumovirus.

Results: A viral cause other than human metapneumovirus was determined for 279 of 687 visits for acute lower respiratory tract illness (41 percent) by 463 children in a population of 2009 infants and children prospectively seen from 1976 to 2001.