Transmission of varicella zoster virus from individuals with herpes zoster or varicella in school and day care settings.

BACKGROUND: Because the varicella incidence has declined following varicella vaccine licensure, herpes zoster (HZ) cases may play a larger role in varicella zoster virus (VZV) transmission. We investigated how HZ and varicella cases contribute to the varicella incidence in schools and day care centers. METHODS: Surveillance data collected in Philadelphia during September 2003-June 2010 were analyzed. A varicella case was considered to be sporadic if it was reported from a school or day care facility >6 weeks after or ≥10 days before other reports of VZV transmission. A varicella case was considered to be secondary if it occurred 10-21 days after report of a case of HZ or sporadic varicella. Analysis compared VZV transmission from individuals with HZ or sporadic varicella, stratified by varicella vaccination status and disease severity. RESULTS: Of 290 HZ cases reported, 27 (9%) resulted in 84 secondary varicella cases. Of 1358 sporadic varicella cases reported, 205 (15%) resulted in 564 secondary varicella cases. Approximately half of the HZ and sporadic varicella cases resulted in single secondary cases. The proportion of individuals who had secondary cases with mild disease was similar for those exposed to HZ and those exposed to varicella (70% and 72%, respectively). VZV transmission was highest from unvaccinated individuals with sporadic varicella (P < .01). CONCLUSIONS: VZV transmission from individuals with HZ contributes to varicella morbidity. More research is needed to understand risk factors and guide recommendations for preventing VZV transmission from individuals with HZ.

Evaluation of laboratory methods for diagnosis of varicella.

BACKGROUND: The incidence of varicella disease is declining as a result of vaccination, making clinical diagnosis more challenging, particularly for vaccine-modified cases. We conducted a comprehensive evaluation of laboratory tests and specimen types to assess diagnostic performance and determine what role testing can play after skin lesions have resolved. METHODS: We enrolled patients with suspected varicella disease in 2 communities. Enrollees were visited at the time of rash onset and 2 weeks later. Multiple skin lesion, oral, urine, and blood or serum specimens were requested at each visit and tested for varicella zoster virus (VZV) immunoglobulin (Ig) G, IgM, and IgA antibody by enzyme-linked immunoassay; for VZV antigen by direct fluorescent antibody; and/or for VZV DNA by polymerase chain reaction (PCR). Clinical certainty of the diagnosis of varicella disease was scored. PCR results from first-visit vesicles or scab specimens served as the gold standard in assessing test performance. RESULTS: Of 93 enrollees, 53 were confirmed to have varicella disease. Among 20 unmodified cases, PCR testing was 95%-100% sensitive for macular and/or papular lesions and for oral specimens collected at the first visit; most specimens from the second visit yielded negative results. Among 27 vaccine-modified cases, macular and/or papular lesions collected at the first visit were also 100% sensitive; yields from other specimens were poorer, and few specimens from the second visit tested positive. Clinical diagnosis was 100% and 85% sensitive for diagnosing unmodified and vaccine-modified varicella cases, respectively. CONCLUSIONS: PCR testing of skin lesion specimens remains convenient and accurate for diagnosing varicella disease in vaccinated and unvaccinated persons. PCR of oral specimens can sometimes aid in diagnosis of varicella disease, even after rash resolves.

Identifying infants at increased risk for late initiation of immunizations: maternal and provider characteristics.

OBJECTIVE: We identified maternal, provider, and community predictors among infants for late initiation of immunizations. METHODS: We performed a retrospective cohort study of infants born between January 1, 2002, and December 31, 2004, in Philadelphia, Pennsylvania. Primary outcomes were age in days at first office-based immunization and status as a late starter (i.e., initiating office-based immunizations after 90 days of age). Candidate predictors included sociodemographic and prenatal characteristics, immunization provider practice type and size, and neighborhood factors. We performed hierarchical logistic regression and Cox regression models to identify independent predictors for being a late starter and prolonged time to first immunization. RESULTS: Of the 65,519 infants from this birth cohort in Philadelphia's immunization registry, 54,429 (88.1%) were included in analysis and 12.6% of these were late starters. Infants whose mothers were younger, received less than five prenatal visits, had less than a high school education, had more than two children, and who smoked cigarettes prenatally were significantly more likely to be late starters. Receiving care at hospital/university-based or public health clinics was also significantly associated with likelihood of being a late starter. Neither distance between infant's residence and practice nor neighborhood socioeconomic indicators was independently associated with the outcomes. Common risk factor profiles based on practice type and four maternal characteristics were found to reliably identify infant risk. CONCLUSIONS: Maternal receipt of fewer prenatal care visits, younger maternal age, higher birth order, and receiving care at public health clinics were the strongest predictors of being a late starter and time to first immunization. Risk factor profiles based on information already collected at birth can be used to identify higher-risk infants. Early intervention and potentially partnering with prenatal care providers may be key strategies for preventing underimmunization.

Experiences and needs of bereaved carers during palliative and end-of-life care for people with chronic obstructive pulmonary disease.

AIM: This study explored the experiences of palliative care that bereaved carers had while providing care to a dying loved one with chronic obstructive pulmonary disease (COPD). METHOD: Semi-structured interviews were undertaken with nine carers who had lost a loved one in the preceding 6 to 24 months. These interviews explored levels of satisfaction with disease management, symptom management, and end-of-life care. With permission, interviews were tape recorded, transcribed, and subjected to content analysis. FINDINGS: Three themes emerged from the data: the impact of the caring experience, the lack of support services, and end-of-life and bereavement support. Carers experienced carer burden, lack of access to support services, a need for palliative care, and bereavement support. CONCLUSION: The findings provide a first insight into the experiences of carers of patients with advanced COPD. Bereaved carers of patients who had suffered advanced COPD reported that they had received inadequate support and had a range of unmet palliative care needs. Special attention should be paid to educating and supporting carers during their caring and bereavement periods to ensure that their quality of life is maintained or enhanced.

Case Analysis of Factors Contributing to Patient Falls.

Falls are a constant risk for patients in acute-care hospitals, which can lead to serious consequences. The purpose of this study was to examine hospital fall case studies and to learn the contributing factors for patient falls. This was achieved by conducting a secondary analysis of 11 fall case studies obtained from two previous studies. The fall cases used the Senior Falls Investigative Methodology (SFIM) approach, which provided detailed analysis of the circumstances surrounding the falls. A total of 549 contributing factors were identified in the 11 case studies, where major categories were classified according to the four different layers of defenses using Reason's Swiss Cheese Model of Accident Causation (organizational factors, supervision, preconditions, and unsafe acts). Hospital policies, reduced supervision, disease processes, the environment, and patients transferring without assistance dominated the reasons for increased risk. Additional strategies were recommended for all layers of defense to reduce patient falls.

Performance of an algorithm for assessing smallpox risk among patients with rashes that may be confused with smallpox.

After the 2001 anthrax bioterror attacks, the Centers for Disease Control and Prevention developed an algorithm to evaluate patients rapidly for suspected smallpox. A prospective, multicenter study examined the performance of this algorithm in assessing patients with an acute, generalized vesicular or pustular rash (AGVPR) admitted to emergency departments and inpatient units of 12 acute-care hospitals in 6 states. Of 26,747 patients (3.5% of all admissions) with rashlike conditions screened, 89 (1.2 patients per 10,000 admissions) had an AGVPR. Physicians or study staff classified none of 73 enrolled patients as being at high risk for having smallpox; 72 (99%) were classified as being at low risk, and 1 was classified as being at moderate risk. The discharge diagnosis for 55 (75%) of these 73 participants was varicella illness. Use of the algorithm did not result in misclassification of AGVPR as high risk for smallpox. The algorithm is a highly specific tool for clinical evaluation of suspected smallpox disease.

Effect of accessibility of influenza vaccination on the rate of childcare staff vaccination.

We assessed the impact of free on-site influenza vaccination on childcare staff vaccination prevalence using 2 before-and-after studies. Vaccination was offered during the 2003-2004 and 2006-2007 influenza seasons. Staff vaccination prevalence was higher in each intervention season compared to the prior, nonintervention season. No baseline characteristics were associated with receipt of vaccination.

Active carers: living with chronic obstructive pulmonary disease.

It has long been recognised that the majority of care provided in chronic illness comes not from health and social care professionals, but from family and friends. One such illness is chronic obstructive pulmonary disease (COPD), a leading cause of morbidity and mortality in the developed world.To explore the specific care needs of informal caregivers of patients with advanced COPD, interviews were conducted with seven active family caregivers. Interviews were taped, transcribed and content analysed to obtain the caregivers' needs. Results confirm that family caregivers provide direct care with little support and assistance. Participants reported restricted activities of daily living and some emotional distress. There were knowledge deficiencies among caregivers relating to the COPD illness trajectory and little awareness of the potential of palliative care. Family caregivers need social and professional support while caring for a patient at home. This would help to ensure that their physical and emotional health does not suffer. There is a need to devise interventions to ensure family caregivers are supported.

Neurologic complications in children hospitalized with influenza: characteristics, incidence, and risk factors.

OBJECTIVE: To determine the characteristics, incidence, and risk factors for influenza-related neurologic complications (INC). STUDY DESIGN: A retrospective cohort study of INC in children hospitalized with laboratory-confirmed influenza infection (LCI) from June 2000 to May 2004 was conducted. Systematic chart review was performed to identify clinical characteristics and outcomes. A neighborhood cohort was constructed to estimate the incidence of INC. Logistic regression was used to identify independent risk factors for INC. RESULTS: Of 842 patients with LCI, 72 patients had an INC: influenza-related encephalopathy (8), post-infectious influenza encephalopathy (2), seizures (56), and other (6). Febrile seizures were the most common type of seizures (27). No patient died from an INC. In our neighborhood cohort, the incidence of INC was 4 cases per 100,000 person-years. An age of 6 to 23 months (odds ratio [OR], 4.2; 95% CI, 1.4-12.5) or 2 to 4 years (OR, 6.3; 95% CI, 2.1-19.1) and an underlying neurologic or neuromuscular disease (OR, 5.6; 95% CI, 3.2-9.6) were independent risk factors for the development of INC. CONCLUSION: Seizures are the most common neurologic complication experienced by children hospitalized with influenza. In the United States, encephalopathy is uncommon. Young children and patients with neurologic or neuromuscular disease are at increased risk for INC.

Routine laboratory testing data for surveillance of rotavirus hospitalizations to evaluate the impact of vaccination.

OBJECTIVE: The recent implementation of a rotavirus vaccination program in the United States makes it imperative to assess the impact of immunization on the incidence of severe rotavirus disease leading to hospitalization. Active surveillance for laboratory-confirmed rotavirus hospitalizations is the ideal approach for surveillance, but requires substantial resources to implement. We examined laboratory and hospital discharge data for 2 tertiary care pediatric hospitals to assess the utility of routine laboratory testing data for surveillance of rotavirus gastroenteritis and to estimate rotavirus disease burden. DESIGN: We obtained all discharge records of hospitalizations for acute gastroenteritis among children <5 years of age at Children's Mercy Hospital (CMH), Kansas City, from July 2000 to June 2005 and at Children's Hospital of Philadelphia (CHOP) from July 2004 to June 2006. We linked these discharge records to laboratory results of rotavirus testing to evaluate epidemiologic differences in children who were tested and not tested for rotavirus and to estimate overall rotavirus burden by extrapolating clinical testing results to the untested group. RESULTS: At CMH, of the 3702 children with acute gastroenteritis, 69% (n = 2552) were discharged during the winter (January through May) months, when rotavirus is most common. Similarly, at CHOP, 62% (n = 779) of the 1261 gastroenteritis discharges occurred during the winter months. During these months, 47% (n = 1197 of 2552) of the discharges at CMH and 56% (n = 438 of 779) of the discharges at CHOP were tested for rotavirus and of those tested, 71% (n = 853 of 1197) and 55% (n = 242 of 438) were positive, respectively. At both hospitals, children with and without rotavirus testing had similar gender and race/ethnicity, but the rate of testing differed by age at CHOP and by month of admission at CMH. After adjusting for these differences, we estimate that 56%-70% of winter and 34%-48% of year-round gastroenteritis in children <5 years can be attributable to rotavirus. Overall, 3%-5% of all hospitalizations in children <5 years of age were caused by rotavirus. CONCLUSIONS: Sentinel hospitals where a large proportion of children hospitalized for gastroenteritis are routinely tested for rotavirus could provide a useful and cost-efficient platform to complement ongoing active surveillance efforts to evaluate the impact of rotavirus vaccination. The data reaffirm the substantial burden of rotavirus hospitalizations in US children and the potential health benefits of vaccination.

Hepatitis A outbreak activity in the United States: responding to a vaccine-preventable disease.

BACKGROUND: The occurrence of hepatitis A in the United States is heterogeneous because of disease cycles with substantial variation in incidence among states and involvement of numerous behavioral risk factors. In spite of the Advisory Committee on Immunization Practices' (ACIP) 1999 recommendation for routine hepatitis A immunization in states with high rates of disease and the fact that disease rates are at a historic low, outbreaks continue to occur. METHODS: We reviewed outbreaks of hepatitis A in the United States occurring from 1994 through 2004. We searched PubMed, ProMed, Google, and the CDC Foodborne Disease Outbreak and Epi-X Internet sites to ascertain the number and type of hepatitis A outbreaks. The CDC's MMWR publication and the Hepatitis Control Report were also searched. RESULTS: A total of 256 hepatitis A outbreaks were identified from 1994 through 2004. The mean number of outbreaks was 23 per year (median 25). The number of outbreaks in states with traditionally low/intermediate endemic rates of hepatitis A remained relatively constant during the study period. Outbreaks declined significantly (P = 0.01) in states with previously high rates of disease--most of which have implemented hepatitis A vaccination programs. CONCLUSIONS: Outbreaks of hepatitis A continue to occur in the United States despite the licensure of two safe and effective vaccines in 1995 and the apparent decline in the number of outbreaks in states with previously high rates of hepatitis A. The recent ACIP recommendation for universal hepatitis A vaccination at age 1 year in all states will contribute to a further reduction in hepatitis A outbreaks.

Validity of self-reported varicella disease history in pregnant women attending prenatal clinics.

OBJECTIVE: The purpose of this study was to assess the validity of self-reported history for varicella disease relative to serological evidence of varicella immunity in pregnant women attending antenatal care at clinics located in two diverse geographical locations in the U.S. (Antelope Valley, California, and Philadelphia) with high varicella vaccination coverage. METHODS: Pregnant women attending prenatal care appointments who needed blood drawn as part of their routine care were eligible to participate. Self-reported varicella disease history was obtained via questionnaire. Varicella serostatus was determined using a whole-cell enzyme-linked immunosorbent assay to test for varicella zoster virus-specific immunoglobulin G (VZV IgG) antibodies. RESULTS: Of the 309 study participants from Antelope Valley and the 528 participants from Philadelphia who self-reported having had chickenpox disease, 308 (99.7%; 95% confidence interval [CI]: 98.2, 100) and 517 (97.9%; 95% CI: 96.3, 99.0), respectively, had serological evidence of immunity to varicella. Only 6.8% (95% CI: 3.9, 11.0) and 17.4% (95% CI: 13.1, 22.5) of women who self-reported having a negative or uncertain varicella disease history in Antelope Valley and Philadelphia, respectively, were seronegative for varicella antibodies. CONCLUSION: Despite the dramatic changes in the epidemiology of varicella that have occurred since 1995 due to the introduction and subsequent widespread use of the varicella vaccine, self-reported history of varicella continues to be a strong predictor of VZV IgG antibodies in pregnant women. Negative or uncertain history remains poorly predictive of negative serostatus.

Risk Factors Associated With Bordetella pertussis Among Infants ≤4 Months of Age in the Pre-Tdap Era: United States, 2002-2005.

BACKGROUND: In the United States, infants have the highest reported pertussis incidence and death rates. Improved understanding of infant risk factors is needed to optimize prevention strategies. METHODS: We prospectively enrolled infants ≤4 months of age with incident-confirmed pertussis from 4 sites during 2002-2005 (preceding pertussis antigen-containing vaccination recommendations for adolescents/adults); each case-patient was age and site matched with 2 control subjects. Caregivers completed structured interviews. Infants and their contacts ≥11 years of age were offered serologic testing for IgG; being seropositive was defined as ≥94 antipertussis toxin IgG enzyme-linked immunosorbent assay units per milliliter. RESULTS: Enrolled subjects (115 case-patients; 230 control subjects) had 4396 contacts during incubation periods; 83 (72%) case-patients had ≥1 contact with prolonged (≥5 days) new cough in primary or secondary households. In multivariable analysis, the odds for pertussis were higher for infants with primary/secondary household contacts who had a prolonged new cough, compared with infants who did not. These contacts included mother [adjusted matched odds ratio (aMOR), 43.8; 95% confidence interval (CI), 6.45-298.0] and ≥1 nonmother contact (aMOR, 20.1; 95% CI, 6.48-62.7). Infants receiving breast milk with 0-1 formula feedings daily had decreased pertussis odds (aMOR, 0.27; 95% CI, 0.08-0.89), compared with those receiving more formula. Of 41 tested case-patients, 37 (90%) were seropositive. CONCLUSIONS: Pertussis in infants was associated with prolonged new cough (≥5 days) in infants' household contacts. Findings suggest that breastfeeding protects against pertussis and warrants recommendation with pertussis prevention strategies, which currently include pertussis vaccination of pregnant mothers and infants' close contacts.

Varicella-zoster vaccine in the USA: success for control of disease severity, but what next?

In the period from 1990 to 1994, before the introduction of a varicella vaccine to the USA, approximately 100 deaths in otherwise healthy individuals, children and adolescents under 20 years of age, were attributable to varicella complications. The administration of a single-dose vaccine has now been widespread in the USA for nearly 10 years; however, since the effectiveness of a single dose in children under 13 years of age in an outbreak situation is approximately 80%, consideration of a second booster dose is in progress although not yet recommended. Licensure of a measles-mumps-rubella-varicella vaccine may hasten the recommendation.

Assessment of screening, treatment, and prevention of perinatal infections in the Philadelphia birth cohort.

Certain population groups are at risk for inadequate prenatal care and transmission of perinatal infections. Philadelphia's birth cohort comprises largely at-risk groups and its infant mortality rate is among the nation's highest. This study identifies factors associated with infectious disease screening, treatment, and prevention in Philadelphia. Delivery charts for a probability sample of 550 patients were reviewed. Demographic factors associated with prenatal and delivery care were identified through Pearson chi-square, analysis of variance, and stepwise logistic regression analysis. Nonstandard and incomplete documentation complicated abstraction. Some prenatal care was noted in 95% of the records and screening varied by disease. Factors independently associated with care include maternal race, insurance status, and maternal age. Screening for infections with well-established recommendations (hepatitis B virus, rubella, syphilis) occurred more often than for group B streptococcus, HIV, hepatitis C virus, and varicella. Adoption of standard reporting forms and processes could improve practice and aid in quality improvement efforts and patient communication.

Neurological and neuromuscular disease as a risk factor for respiratory failure in children hospitalized with influenza infection.

CONTEXT: The Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for children with certain chronic medical conditions to prevent serious complications of influenza infection. Little is known about the relative contribution of each of these chronic medical conditions to the development of serious influenza-associated complications. OBJECTIVE: To identify chronic medical conditions that are associated with respiratory failure in children hospitalized with community-acquired laboratory-confirmed influenza. DESIGN, SETTING, AND PATIENTS: A retrospective cohort study of patients aged 21 years or younger hospitalized at The Children's Hospital of Philadelphia with community-acquired laboratory-confirmed influenza during 4 consecutive influenza seasons (June 2000 through May 2004). We examined 9 ACIP-designated high-risk chronic medical conditions and 3 additional chronic medical conditions (neurological and neuromuscular disease [NNMD], gastroesophageal reflux disease [GERD], and history of prematurity) that in recent studies have been associated with influenza hospitalization and severe influenza-related complications. MAIN OUTCOME MEASURES: Rate and odds ratio (OR) of respiratory failure, defined as need for mechanical ventilation. RESULTS: Of 745 children hospitalized with community-acquired laboratory-confirmed influenza, 322 (43%) had 1 or more ACIP-designated high-risk chronic medical conditions. Neurological and neuromuscular disease, GERD, and history of prematurity were present in 12%, 14%, and 3%, of children, respectively. Thirty-two children (4.3%) developed respiratory failure. In multivariate logistic regression analyses, conditions associated with respiratory failure included NNMD (OR, 6.0; 95% confidence interval [CI], 2.7-13.5), chronic pulmonary disease other than asthma (OR, 4.8; 95% CI, 1.5-15.1), and cardiac disease (OR, 4.0; 95% CI, 1.6-10.2). The predicted probabilities of respiratory failure derived from the multivariate model were 12% (95% CI, 7%-20%), 9% (95% CI, 3%-23%), and 8% (95% CI, 4%-18%) for children with NNMD, chronic pulmonary disease, and cardiac disease, respectively. CONCLUSIONS: These results support the ACIP's recent decision to add NNMD to the list of conditions for which annual influenza vaccine is recommended in children. Neurologists and primary care pediatricians should be alerted to the increased risk of respiratory failure and the importance of influenza vaccination in children with NNMD.

Chickenpox or smallpox: the use of the febrile prodrome as a distinguishing characteristic.

BACKGROUND: The ability to differentiate chickenpox from smallpox is important for early recognition of bioterrorism events and prevention of false alarms. The febrile prodrome is a clinical feature used to differentiate these conditions. However, the prevalence of prodromal manifestations in chickenpox has not been well established. METHODS: We evaluated prodrome characteristics of all chickenpox cases identified through an active varicella surveillance program over a 21-month period. The frequencies of various prodromal manifestations among vaccinated and unvaccinated case patients were assessed, and the impact of other demographic features on these manifestations was evaluated. Data were analyzed to determine what proportion met the smallpox febrile prodrome criteria as elaborated in the Centers for Disease Control and Prevention algorithm for evaluating patients suspected of having smallpox. Finally, we compared our data with historical data on smallpox prodromes. RESULTS: Data on prodrome characteristics were available for 932 chickenpox cases. Prodromal fever was present in 37% of unvaccinated chickenpox case patients and in 25% of vaccinated case patients. Among unvaccinated case patients, adults were 70% more likely than children to have fever in the prodrome period. We found that prodromes are less common and less severe in chickenpox than in smallpox. Nevertheless, 7%-17% of unvaccinated chickenpox case patients meet the smallpox febrile prodrome criteria. CONCLUSIONS: Febrile prodromes occur in a significant proportion of patients with chickenpox, particularly among unvaccinated case patients and adults. Therefore, the febrile prodrome alone is not a sufficient marker of smallpox risk. All major and minor smallpox criteria should be considered together in assessing the likelihood of smallpox.

Ten year follow-up of healthy children who received one or two injections of varicella vaccine.

BACKGROUND: The rate of varicella and persistence of varicella antibody after a one dose vs. a two dose regimen of varicella virus vaccine live Oka/Merck (VARIVAX; Merck & Co., Inc., West Point, PA) in approximately 2000 children were compared during a 9- to 10-year follow-up period. METHODS: Children 12 months to 12 years of age with a negative history of varicella were randomized in late 1991 to early 1993 to receive either one or two injections of varicella vaccine given 3 months apart. Subjects were actively followed for varicella, any varicella-like illness or zoster and any exposures to varicella or zoster on a yearly basis for 10 years after vaccination. Persistence of varicella antibody was measured yearly for 9 years. RESULTS: Most cases of varicella reported in recipients of one or two injections of vaccine were mild. The risk of developing varicella >42 days postvaccination during the 10-year observation period was 3.3-fold lower (P < 0.001) in children who received two injections than in those who received one injection (2.2% vs. 7.3%, respectively). The estimated vaccine efficacy for the 10-year observation period was 94.4% for one injection and 98.3% for two injections (P < 0.001). Measurable serum antibody persisted for 9 years in all subjects. CONCLUSIONS: Administration of either one or two injections of varicella vaccine to healthy children results in long term protection against most varicella disease. The two dose regimen was significantly more effective than a single injection.

Safety, immunogenicity and efficacy in healthy infants of G1 and G2 human reassortant rotavirus vaccine in a new stabilizer/buffer liquid formulation.

BACKGROUND: A refrigerator-stable rotavirus (RV) vaccine that withstands gastric acid is anticipated to permit more widespread use of RV vaccine. OBJECTIVE: We investigated for the first time in infants an oral, liquid formulation of G1 and G2 human bovine reassortant rotavirus vaccine (HRRV) with a new stabilizer/buffer (S/B) containing sucrose, sodium phosphate and sodium citrate. METHODS: During 1997 through 1998, 731 healthy infants approximately 2 to 4 months of age were enrolled at 19 US sites to receive 3 HRRV or placebo doses approximately 6 to 8 weeks apart in a partially double blinded study. Infants were randomized to: (1) HRRV with no S/B but with prefeeding; (2) HRRV plus 1 of 3 different concentrations/volumes of S/B; or (3) placebo. RESULTS: No serious vaccine-related adverse experiences or intussusception cases were reported. No statistically significant differences were observed between vaccine and placebo recipients for fever (> or =38.1 degrees C) 0 to 7 days after any dose, irritability, vomiting or diarrhea incidence 0 to 42 days after any dose. Vaccine virus shedding among vaccine recipients was uncommon. Among S/B vaccine groups, proportions of infants with a > or =3-fold titer rise from baseline to Postdose 3 for G1 serum-neutralizing antibody (SNA), G2 SNA, WC3 SNA, serum anti-RV IgA, serum anti-RV IgG and stool anti-RV IgA were generally similar to those of the prefed non-S/B group. CONCLUSIONS: HRRV with a new S/B was generally well-tolerated; immunogenicity was generally similar to the prefed non-S/B group. No intussusception cases were reported, but the small sample size precluded a definitive conclusion. A large international clinical study is under way to address safety and efficacy of an S/B formulation of a pentavalent version of HRRV.

A cluster of primary varicella cases among healthcare workers with false-positive varicella zoster virus titers.

BACKGROUND: Five cases of primary varicella zoster virus (VZV) we re diagnosed among hospital healthcare workers (HCWs). All had complied with a pre-employment VZV screening program and had been considered immune. OBJECTIVES: To summarize the investigation of VZV among un-immunized HCWs and to provide recommendations for avoiding false-positive serologic tests. DESIGN: Risk of transmission of VZV to susceptible HCWs is minimized through serologic screening. Varicella vaccine is recommended for susceptible HCWs. A commercially available latex bead agglutination assay (LA) is widely used because it is rapid and easy to perform. LA was compared with the whole-cell varicella ELISA standardized in the Centers for Disease Control and Prevention (CDC) National Herpes Laboratory. SETTING/POPULATION: Large inner-city, tertiary-employee population. RESULTS: In a year, 5 HCWs presented with laboratory-confirmed primary varicella infection. Four had VZV exposures 2 weeks prior to presentation. All had documented positive VZV titers by LA performed at hire. None were offered VZV vaccination. The original LAs were judged false-positives. INTERVENTION/FOLLOW-UP INVESTIGATION: Fifty-three consecutive VZV LA samples from the hospital laboratory were retested at the CDC. Forty-four samples concurred. Of the remaining 9, 4 were positive by hospital LA but negative by CDC IgG ELISA. Four were equivocal by hospital LA but negative by CDC IgG ELISA and LA. One was positive by hospital LA but negative by LA and equivocal by ELISA at the CDC. CONCLUSION: LA may be prone to false-positive results and inappropriate for screening hospital HCWs.