Recombinant MVA-prime elicits neutralizing antibody responses by inducing antigen-specific B cells in the germinal center.

The RV144 HIV-1 vaccine trial has been the only clinical trial to date that has shown any degree of efficacy and associated with the presence of vaccine-elicited HIV-1 envelope-specific binding antibody and CD4+ T-cell responses. This trial also showed that a vector-prime protein boost combined vaccine strategy was better than when used alone. Here we have studied three different priming vectors-plasmid DNA, recombinant MVA, and recombinant VSV, all encoding clade C transmitted/founder Env 1086 C gp140, for priming three groups of six non-human primates each, followed by a protein boost with adjuvanted 1086 C gp120 protein. Our data showed that MVA-priming favors the development of higher antibody binding titers and neutralizing activity compared with other vectors. Analyses of the draining lymph nodes revealed that MVA-prime induced increased germinal center reactivity characterized by higher frequencies of germinal center (PNAhi) B cells, higher frequencies of antigen-specific B-cell responses as well as an increased frequency of the highly differentiated (ICOShiCD150lo) Tfh-cell subset.

Use of antimicrobial agents in United States neonatal and pediatric intensive care patients.

OBJECTIVE: Antimicrobial use contributes to the development of emergence and dissemination of antimicrobial-resistant bacteria among intensive care unit (ICU) patients. There are few published data on antimicrobial use in neonatal (NICU) and pediatric ICU (PICU) patients. METHODS: Personnel at 31 Pediatric Prevention Network hospitals participated in point prevalence surveys on August 4, 1999 (summer) and February 8, 2000 (winter). Data collected for all NICU and PICU inpatients included demographics, antimicrobials and indications for use and therapeutic interventions. RESULTS: Data were reported for 2647 patients in 29 NICUs (827 patients in summer; 753 in winter) and 35 PICUs (512 patients in summer; 555 in winter). PICU patients were more likely than NICU patients to be receiving antimicrobials on the survey date [758 of 1070 (70.8%) versus 684 of 1582 (43.2%), P < 0.0001]. NICU patients were receiving a higher median number of antimicrobials (2 versus 1, P < 0.0001). The most common agents among NICU patients were gentamicin, ampicillin and vancomycin; the most common agents among PICU patients were cefazolin, vancomycin and cefotaxime. Use of aminoglycosides, aminopenicillins and topical antibacterials was significantly more common in NICU patients; first, second and third generation cephalosporins, extended spectrum penicillins, sulfonamides, fluoroquinolones, antianaerobic agents, systemic antifungals and systemic antivirals were more common in PICU patients. CONCLUSIONS: This is the first U.S. national multicenter description of antimicrobial use in NICUs and PICUs and demonstrates the high prevalence of antimicrobial use among these patients. Assessment strategies targeting antimicrobial use in pediatrics are needed.

Improving influenza immunization rates among healthcare workers caring for high-risk pediatric patients.

OBJECTIVE: To assess influenza vaccination rates of healthcare workers (HCWs) in neonatal intensive care units (NICUs), pediatric intensive care units (PICUs), and oncology units in Pediatric Prevention Network (PPN) hospitals. PARTICIPANTS: Infection control practitioners and HCWs in NICUs, PICUs, and oncology units. METHODS: In November 2000, posters, electronic copies of a slide presentation, and an influenza fact sheet were distributed to 32 of 76 PPN hospitals. In January 2001, a survey was distributed to PPN hospital participants to obtain information about the immunization campaigns. On February 7, 2001, a survey of influenza immunization was conducted among HCWs in NICU, PICU, and oncology units at participating hospitals. RESULTS: Infection control practitioners from 19 (25%) of the 76 PPN hospitals completed the surveys. The median influenza immunization rate was 43% (range, 12% to 63%), with 7 hospitals exceeding 50%. HCWs (n = 1123) at 15 PPN hospitals completed a survey; 53% of HCWs reported receiving influenza immunization. Immunization rates varied by work site: 52% in NICUs and PICUs compared with 60% in oncology units. Mobile carts and PPN educational fact cards were associated with higher rates among these subpopulations (P < .001) (361 [63%] of 575 vs 236 [44%] of 541 for mobile carts; 378 [60%] of 633 vs 219 [45%] of 483 for fact cards). CONCLUSION: Despite delayed distribution of influenza vaccine during the 2000-2001 season, immunization rates at 7 hospitals and among HCWs in high-risk units exceeded the National Association of Children's Hospitals and Related Institutions goal of 50%.

Health effects in community residents near a uranium plant at Fernald, Ohio, USA.

OBJECTIVES: Health outcomes in persons who lived in the area surrounding a U.S. Department of Energy (DOE) uranium processing plant near Fernald, Ohio were evaluated using data of Fernald Medical Monitoring Program (FMMP) participants. METHODS: Residential history information was used to identify participants who lived in close proximity to the plant (less than 2 miles), in the direction of groundwater runoff (south of the plant), or used a well or cistern as a drinking water source. Standardized prevalence ratios (SPRs) for certain disease endpoints were calculated using the U.S. National Health Interview Survey(NHIS) and the National Health and Nutrition Examination Survey (NHANES) data files for comparison rates. RESULTS: Findings suggest that prior living within the Fernald exposure domain is related to increased prevalence of urinary system disease. Statistically significant elevations of bladder disease (standardized prevalence ratio or SPR = 1.32) and kidney disease (SPR = 2.15), including sub-categories, kidney stones (SPR = 3.98) and chronic nephritis (SPR = 2.03) were noted, as well as increased rates for hematuria and urethral stricture. In regression analyses with adjustment forage and sex, serum creatinine levels were increased in those who had lived close to the plant. Increased white blood cell count and hemoglobin levels, and decreased mean corpuscular volume were also found in those living less than 2 miles from the plant. Those who used a well or cistern for drinking water were found to have increased urinary microalbumin, red blood cell count and hematocrit. CONCLUSIONS: These preliminary findings will provide the basis for future hypothesis testing incorporating important determinants of exposure not included in this study, such as duration and calendar year of exposure, location relevant to prevailing wind direction, and age at exposure.

Behavioral Health Homes: an opportunity to address healthcare inequities in people with serious mental illness.

People with serious mental illness (SMI) face striking reductions in lifespan versus the general population, in part due to the inadequacy of healthcare systems in meeting the substantial physical health needs of this group. Integrated care, the strategic combination and coordination of behavioral health and primary care services, has been proposed as a potential healthcare service delivery solution to address these care gaps. Inspired by the primary care Patient-Centered Medical Home concept, Behavioral Health Homes bring primary care services into the community mental health center in various ways. In this paper the authors review the literature describing Behavioral Health Home interventions and highlight an integration project that provides co-located and coordinated primary care and wellness services in a community mental health center. Such approaches hold great promise for improving the health and healthcare of people with SMI.

Establishment and maintenance of a PBMC repository for functional cellular studies in support of clinical vaccine trials.

A large repository of cryopreserved peripheral blood mononuclear cells (PBMCs) samples was created to provide laboratories testing the specimens from human immunodeficiency virus-1 (HIV-1) vaccine clinical trials the material for assay development, optimization, and validation. One hundred thirty-one PBMC samples were collected using leukapheresis procedure between 2007 and 2013 by the Comprehensive T cell Vaccine Immune Monitoring Consortium core repository. The donors included 83 human immunodeficiency virus-1 (HIV-1) seronegative and 32 HIV-1 seropositive subjects. The samples were extensively characterized for the ability of T cell subsets to respond to recall viral antigens including cytomegalovirus, Epstein-Barr virus, influenza virus, and HIV-1 using Interferon-gamma (IFN-γ) enzyme linked immunospot (ELISpot) and IFN-γ/interleukin 2 (IL-2) intracellular cytokine staining (ICS) assays. A subset of samples was evaluated over time to determine the integrity of the cryopreserved samples in relation to recovery, viability, and functionality. The principal results of our study demonstrate that viable and functional cells were consistently recovered from the cryopreserved samples. Therefore, we determined that this repository of large size cryopreserved cellular samples constitutes a unique resource for laboratories that are involved in optimization and validation of assays to evaluate T, B, and NK cellular functions in the context of clinical trials.

Adenovirus-5-vectored P. falciparum vaccine expressing CSP and AMA1. Part B: safety, immunogenicity and protective efficacy of the CSP component.

BACKGROUND: A protective malaria vaccine will likely need to elicit both cell-mediated and antibody responses. As adenovirus vaccine vectors induce both these responses in humans, a Phase 1/2a clinical trial was conducted to evaluate the efficacy of an adenovirus serotype 5-vectored malaria vaccine against sporozoite challenge. METHODOLOGY/PRINCIPAL FINDINGS: NMRC-MV-Ad-PfC is an adenovirus vector encoding the Plasmodium falciparum 3D7 circumsporozoite protein (CSP). It is one component of a two-component vaccine NMRC-M3V-Ad-PfCA consisting of one adenovector encoding CSP and one encoding apical membrane antigen-1 (AMA1) that was evaluated for safety and immunogenicity in an earlier study (see companion paper, Sedegah et al). Fourteen Ad5 seropositive or negative adults received two doses of NMRC-MV-Ad-PfC sixteen weeks apart, at 1 x 1010 particle units per dose. The vaccine was safe and well tolerated. All volunteers developed positive ELISpot responses by 28 days after the first immunization (geometric mean 272 spot forming cells/million[sfc/m]) that declined during the following 16 weeks and increased after the second dose to levels that in most cases were less than the initial peak (geometric mean 119 sfc/m). CD8+ predominated over CD4+ responses, as in the first clinical trial. Antibody responses were poor and like ELISpot responses increased after the second immunization but did not exceed the initial peak. Pre-existing neutralizing antibodies (NAb) to Ad5 did not affect the immunogenicity of the first dose, but the fold increase in NAb induced by the first dose was significantly associated with poorer antibody responses after the second dose, while ELISpot responses remained unaffected. When challenged by the bite of P. falciparum-infected mosquitoes, two of 11 volunteers showed a delay in the time to patency compared to infectivity controls, but no volunteers were sterilely protected. SIGNIFICANCE: The NMRC-MV-Ad-PfC vaccine expressing CSP was safe and well tolerated given as two doses, but did not provide sterile protection. TRIAL REGISTRATION: ClinicalTrials.gov NCT00392015.

Equivalence of ELISpot assays demonstrated between major HIV network laboratories.

BACKGROUND: The Comprehensive T Cell Vaccine Immune Monitoring Consortium (CTC-VIMC) was created to provide standardized immunogenicity monitoring services for HIV vaccine trials. The ex vivo interferon-gamma (IFN-γ) ELISpot is used extensively as a primary immunogenicity assay to assess T cell-based vaccine candidates in trials for infectious diseases and cancer. Two independent, GCLP-accredited central laboratories of CTC-VIMC routinely use their own standard operating procedures (SOPs) for ELISpot within two major networks of HIV vaccine trials. Studies are imperatively needed to assess the comparability of ELISpot measurements across laboratories to benefit optimal advancement of vaccine candidates. METHODS: We describe an equivalence study of the two independently qualified IFN-g ELISpot SOPs. The study design, data collection and subsequent analysis were managed by independent statisticians to avoid subjectivity. The equivalence of both response rates and positivity calls to a given stimulus was assessed based on pre-specified acceptance criteria derived from a separate pilot study. FINDINGS: Detection of positive responses was found to be equivalent between both laboratories. The 95% C.I. on the difference in response rates, for CMV (-1.5%, 1.5%) and CEF (-0.4%, 7.8%) responses, were both contained in the pre-specified equivalence margin of interval [-15%, 15%]. The lower bound of the 95% C.I. on the proportion of concordant positivity calls for CMV (97.2%) and CEF (89.5%) were both greater than the pre-specified margin of 70%. A third CTC-VIMC central laboratory already using one of the two SOPs also showed comparability when tested in a smaller sub-study. INTERPRETATION: The described study procedure provides a prototypical example for the comparison of bioanalytical methods in HIV vaccine and other disease fields. This study also provides valuable and unprecedented information for future vaccine candidate evaluations on the comparison and pooling of ELISpot results generated by the CTC-VIMC central core laboratories.

Evaluation and treatment of neonates with suspected late-onset sepsis: a survey of neonatologists' practices.

OBJECTIVE: To ascertain current diagnostic and treatment practices for suspected late-onset sepsis in infants in neonatal intensive care units (NICUs) and identify areas that may benefit from clinical practice guidelines. METHODS: During June 2000, we conducted a multicenter survey of neonatologists and infection control professionals regarding practices related to late-onset sepsis in NICUs at children's hospitals participating in the Pediatric Prevention Network. RESULTS: Personnel at 35 hospitals with NICUs completed surveys; 34 were infection control professionals, and 278 were neonatology clinicians, primarily attending neonatologists or neonatology fellows. At these facilities, coagulase-negative staphylococci (CoNS) were the most frequent blood culture isolate from infants with late-onset sepsis accounting for 54% of bloodstream infections. When late-onset sepsis was suspected, 83% of clinicians drew only 1 blood culture when no central venous catheter was present or when a central vascular was present with no blood return. Thirty-two percent obtained 1 or more C-reactive protein concentration determinations. Sixty percent of clinicians prescribed a vancomycin-containing regimen for a 900 g, 3-week-old infant with suspected late-onset sepsis. The presence of a central venous catheter or shock increased empiric vancomycin use. The presence of methicillin-resistant Staphylococcus aureus in the NICU did not increase vancomycin use, but a vancomycin restriction policy decreased empiric vancomycin use. Clinicians at an individual NICU tended to have similar empiric antibiotic-prescribing practices: in 29 (83%) of 35 centers > or =75% of respondents had similar practice with regard to prescribing a vancomycin-containing regimen for empiric therapy. Forty-seven percent to 85% completed a full course of antimicrobials when a single blood culture was obtained and grew CoNS, but a significantly lower percentage of respondents (22%-47%) completed a full course when 1 of 2 blood cultures obtained grew CoNS. Eleven percent of respondents removed an umbilical catheter at the time of suspected sepsis, but fewer than 5% removed a nonumbilical central venous catheter for suspected sepsis. Most (> or =61%) retained a nonumbilical catheter despite documentation of CoNS bacteremia. CONCLUSIONS: Neonatologists varied in management of suspected late-onset sepsis, particularly that caused by CoNS. Procedures to prevent CoNS-positive blood cultures and to differentiate CoNS contaminants from pathogens are needed. For safely decreasing vancomycin use in NICUs, clinical practice guidelines should be developed, implemented, and evaluated. The guidelines should include optimal skin antisepsis and catheter disinfection before obtaining blood for culture, obtaining 2 blood cultures and using adjunctive tests and information to help differentiate contaminants from pathogens, and restriction on empiric vancomycin use.

Vancomycin use in hospitalized pediatric patients.

OBJECTIVES: To assess vancomycin utilization at children's hospitals, to determine risk factors for vancomycin use and length of therapy, and to facilitate adapting recommendations to optimize vancomycin prescribing practices in pediatric patients. METHODS: Two surveys were conducted at Pediatric Prevention Network hospitals. The first (Survey I) evaluated vancomycin control programs. The second (Survey II) prospectively reviewed individual patient records. Each hospital was asked to complete questionnaires on 25 consecutive patients or all patients for whom vancomycin was prescribed during a 1-month period. RESULTS: In Survey I, 55 of 65 (85%) hospitals reported their vancomycin control policies. Three quarters had specific policies in place to restrict vancomycin use. One half had at least 3 vancomycin restriction measures. In Survey II, personnel at 22 hospitals reviewed 416 vancomycin courses, with 2 to 25 (median = 12) patients tracked per hospital. Eighty-two percent of the vancomycin prescribed was for treatment of neonatal sepsis, fever/neutropenia, fever of unknown origin, positive blood culture, pneumonia, or meningitis. In an additional 6% (26/416), vancomycin was prescribed for patients with beta-lactam allergies and in 13% (56/416) for prophylaxis. Median duration of prophylaxis was 2 days (range: 1-15 days). Almost half (196, 47%) of the patients who received vancomycin were in intensive care units; 27% of the vancomycin courses were initiated by neonatologists and 19% by hematologists/oncologists. The predominant risk factor at the time of vancomycin initiation was the presence of vascular catheters (322, 77%); other host factors included cancer chemotherapy (55, 13%), transplant (30, 7%), shock (24, 6%), other immunosuppressant therapy (17, 4%), or hyposplenic state (2, <1%). Other clinical considerations were severity of illness (96, 23%), uncertainty about diagnosis (51, 12%), patient not responding to current antibiotic therapy (40, 10%), or implant infection (13, 3%). When vancomycin was initiated, blood cultures were positive in 85 patients (20%); cultures from other sites were positive in 45 (11%), and Gram stains of body fluids were positive in 37 (9%). In 29 (7%) patients, organisms sensitive only to vancomycin were isolated before vancomycin initiation. Reasons for discontinuing vancomycin included: therapeutic course completed (125, 30%), negative cultures (106, 25%), alternative antibiotics initiated (75, 18%), illness resolved (14, 3%), or patient expired (13, 3%). Final results of blood culture isolates resistant to beta-lactam antibiotics included 48 coagulase-negative staphylococcus, 5 Staphylococcus aureus, and 10 other species. CONCLUSIONS: At children's hospitals, vancomycin is initiated for therapy in patients who have vascular catheters and compromised host factors. Only 7% had laboratory-confirmed beta-lactam-resistant organisms isolated at the time vancomycin was prescribed. Efforts to modify empiric vancomycin use in children's hospitals should be targeted at intensivists, neonatologists, and hematologists. Initiatives to decrease length of therapy by decreasing the number of surgical prophylaxis doses and days of therapy before laboratory results may decrease vancomycin exposure.

A national point-prevalence survey of pediatric intensive care unit-acquired infections in the United States.

OBJECTIVE: To determine the prevalence of intensive care unit-acquired infections, a major cause of morbidity in pediatric intensive care unit (PICU) patients. METHODS: Pediatric Prevention Network hospitals (n = 31) participated in a point-prevalence survey on August 4, 1999. Data collected for all PICU inpatients included demographics, infections, therapeutic interventions, and outcomes. RESULTS: There were 512 patients in 35 PICUs. The median age was 2.2 years (range, <1 day-35.4 years). Seventy-five PICU-acquired infections occurred among 61 (11.9%) patients. The most frequently reported sites were bloodstream (31 [41.3%]), lower respiratory tract (17 [22.7%]), urinary tract (10 [13.3%]), or skin/soft tissue (6 [8.0%]). The most frequent pathogens were coagulase-negative staphylococci (in 16 [21.3%] infections), Candida spp. (13 [17.3%]), enterococci (10 [13.3%]), Staphylococcus aureus (9 [12.0%]), or Pseudomonas aeruginosa (8 [10.7%]). Age-adjusted risk factors for infection included central intravenous catheters (relative risk [RR], 4.1; 95% confidence intervals [CI], 2.4-7.1), arterial catheters (RR, 2.4; 95% CI, 1.5-3.9), total parenteral nutrition (RR, 5.5; 95% CI, 3.6-8.5), or mechanical ventilation (RR, 3.9; 95% CI, 2.2-6.8). Infection was associated with higher age-adjusted risk of death within 4 weeks of the survey (RR, 3.4; 95% CI, 1.7-6.5). CONCLUSIONS: This national multicenter study documented the high prevalence of PICU-acquired infections. Preventing these infections should be a national priority.