Formal instruction and continuing education engagement as factors improving small animal general practitioners discussing nutrition with clients.

OBJECTIVE: Evaluate whether general practitioners' formal small animal (canine and feline) nutrition instruction in veterinary school and the amount and type of continuing education engagement affect perceived self-reported confidence and frequency in discussing nutrition with clients. SAMPLE: 403 small animal veterinarians who responded to an online survey distributed through the American Animal Hospital Association. PROCEDURES: Veterinarians were surveyed regarding perceived amount of formal instruction received in veterinary school, interest, time committed to self-education, and confidence in both self and staff knowledge in small animal nutrition. RESULTS: Of those veterinarians who responded to the survey, 57.1% (201/352) reported they received "none" or "very little" formal instruction in small animal nutrition, while 151 of 352 answered "some" or "a significant amount." Veterinarians with more formal instruction and veterinarians who reported spending more time in self-education had increased confidence in their own nutritional knowledge (P < .01) and that of their staff (P < .01). CLINICAL RELEVANCE: Veterinarians with self-reported significant formal instruction and veterinarians with higher continuing education engagement were more confident in their knowledge and their staff's knowledge regarding therapeutic and nontherapeutic small animal nutrition. Therefore, it is important for the profession to address veterinary nutrition education gaps in order to increase the veterinary healthcare team's engagement in nutritional discussions with their clients for both healthy and sick pets.

Small animal general practitioners discuss nutrition infrequently despite assertion of indication, citing barriers.

OBJECTIVE: To determine what perceived factors prevent small animal general practitioners from discussing pet nutrition with clients during healthy and sick pet appointments. SAMPLE: 403 veterinarians in small animal general practice. PROCEDURES: An online survey was used to gather veterinarians' opinions on perceived barriers, knowledge levels, and confidence regarding pet nutrition discussions. RESULTS: Reported barriers to discussing nutrition during healthy pet appointments included client resistance to changing brand (149/359), time constraints (146/359), misinformation online (138/359), and difficulty keeping up with products (132/359). Reported barriers to discussing nutrition during sick pet appointments included client cost concerns (101/349), pet not accepting new food (99/349), and time constraints (83/349). Veterinarians reported discussing nutrition less during healthy pet appointments, compared to sick pet appointments, and were significantly less confident with their knowledge regarding nontherapeutic food, compared to therapeutic food. Veterinarians also reported that they perceived conversations about therapeutic foods to be more positive than conversations about nontherapeutic foods, and veterinarians with more years in practice more commonly reported that there was nothing that would dissuade them from discussing nutrition. Veterinarians who reported barriers to discussing nutrition described a need for resources and reliable information for health-care teams and clients. CLINICAL RELEVANCE: Results demonstrated a substantial gap between veterinarians' assertion that nutrition conversations are indicated and the frequency with which they discuss nutrition during appointments. Veterinarians reported that they felt their nutrition conversations were frequently positive; therefore, it is important to overcome barriers to engage with clients about pet nutrition.

Comparison of air kerma rate between the S7500 and S7600 xoft axxent sources.

PURPOSE: The purpose of this work was to evaluate differences in air-kerma rate of the older, S7500 water-cooled Xoft Axxent source and newer, S7600 Galden-cooled source. METHODS AND MATERIALS: The Attix Free Air Chamber (FAC) at the UWMRRC was used to measure the air-kerma rate at 50 cm for six S7600 Xoft Axxent sources. The average measured air-kerma of the S7600 sources was compared with the measured average air-kerma rate from five S7500 sources. The air-kerma rates of the S7500 sources were measured in a Standard Imaging HDR 1000+ well chamber. The FAC measurements were used to determine a well chamber calibration coefficient for the S7600 source. The S7500 calibration coefficients were incorrectly applied to the S7600 sources to indicate the magnitude of error that can occur if the incorrect calibration coefficient is used. RESULTS: A 10.3% difference was observed between the average air-kerma rates of the two sources although a 17% difference was observed between their calibration coefficients. The application of the S7500 calibration coefficient to the S7600 sources resulted in measured air-kerma rates that were 20% greater than the true value. CONCLUSIONS: This work indicates the need for a new air-kerma rate standard for the S7600 sources, and the results presented in this work are indicative of values that would be obtained at National Institute of Standards and Technology.

Metagenomic sequencing generates the whole genomes of porcine rotavirus A, C, and H from the United States.

The genus Rotavirus comprises eight species, designated A to H, and two recently identified tentative species I in dogs and J in bats. Species Rotavirus A, B, C and H (RVA, RVB, RVC and RVH) have been detected in humans and animals. While human and animal RVA are well characterized and defined, complete porcine genome sequences in the GenBank are limited compared to human strains. Here, we used a metagenomic approach to sequence the 11 segments of RVA, RVC and RVH strains from piglets in the United States (US) and explore the evolutionary relations of these RV species. Metagenomics identified Astroviridae, Picornaviridae, Caliciviridae, Coronoviridae in samples MN9.65 and OK5.68 while Picobirnaviridae and Arteriviridae were only identified in sample OK5.68. Whole genome sequencing and phylogenetic analyses identified multiple genotypes with the RVA of strain MN9.65 and OK5.68, with the genome constellation of G5/G9-P[7]/P[13]-I5/I5- R1/R1-C1-M1-A8-N1-T7-E1/E1-H1 and G5/G9-P[6]/P[7]-I5-R1/R1-C1-M1-A8-N1-T1/T7-E1/E1-H1, respectively. The RVA strains had a complex evolutionary relationship with other mammalian strains. The RVC strain OK5.68 had a genome constellation of G9-P[6]-I1-R1-C5-M6-A5-N1-T1-E1-H1, and shared an evolutionary relationship with porcine strains from the US. The RVH strains MN9.65 and OK5.68 had the genome constellation of G5-P1-I1-R1-C1-M1-A5-N1-T1-E4-H1 and G5-P1-I1-R1-C1-M1-A5-N1-T1-E1-H1, indicating multiple RVH genome constellations are circulating in the US. These findings allow us to understand the complexity of the enteric virome, develop improved screening methods for RVC and RVH strains, facilitate expanded rotavirus surveillance in pigs, and increase our understanding of the origin and evolution of rotavirus species.

Antenatal blood transfusion in South Africa: indications and practice in a high-HIV-prevalence setting.

BACKGROUND: Globally, data on antenatal blood transfusion practices are scarce. We sought to characterize the epidemiology of antenatal transfusion in South Africa. STUDY DESIGN AND METHODS: A cross-sectional study was conducted of women who were transfused during pregnancy (>48 hr before anticipated delivery) at two hospitals in Durban and Soweto in 2014 to 2015. Medical record data on demographics, obstetric history, anemia, HIV status, and indications for blood transfusion were abstracted. RESULTS: The records on a total of 560 transfused pregnant women were evaluated; mean age was 28 years, 98% were of black African ethnicity, and 28% were HIV positive. At time of transfusion, one-half were in the first trimester. Hemorrhage was noted in 76% of women, most of which was associated with abortion (67%) or ectopic pregnancy (27%). Most women were transfused with red blood cells (RBCs; median, 2 units); 14% of women were transfused with plasma and 2% with platelets. Median pre- and posttransfusion hemoglobin levels were 6.9 g/dL and 9.2 g/dL, respectively; the latter differed by hospital (8.7 g/dL vs. 9.5 g/dL; p < 0.01). Hemorrhage was associated with missing HIV status, lower gestational age, and transfusion of 3 or more RBC units (all p < 0.01). In contrast, diagnoses of anemia (Soweto only) were associated with HIV infection, later gestational age, and lower (<3 units) RBC dose (all p < 0.01). CONCLUSION: Abortion and ectopic pregnancy with associated hemorrhage were the leading indications for antenatal transfusion and were concentrated in early gestation. By contrast, anemia was associated with HIV infection and transfusion in the third trimester.

Deformable abdominal phantom for the validation of real-time image guidance and deformable dose accumulation.

PURPOSE: End-to-end testing with quality assurance (QA) phantoms for deformable dose accumulation and real-time image-guided radiotherapy (IGRT) has recently been recommended by American Association of Physicists in Medicine (AAPM) Task Groups 132 and 76. The goal of this work was to develop a deformable abdominal phantom containing a deformable three-dimensional dosimeter that could provide robust testing of these systems. METHODS: The deformable abdominal phantom was fabricated from polyvinyl chloride plastisol and phantom motion was simulated with a programmable motion stage and plunger. A deformable normoxic polyacrylamide gel (nPAG) dosimeter was incorporated into the phantom apparatus to represent a liver tumor. Dosimeter data were acquired using magnetic resonance imaging (MRI). Static measurements were compared to planned dose distributions. Static and dynamic deformations were used to simulate inter- and intrafractional motion in the phantom and measurements were compared to baseline measurements. RESULTS: The statically irradiated dosimeters matched the planned dose distribution with an average γ pass rates of 97.0 ± 0.5% and 97.5 ± 0.2% for 3%/5 mm and 5%/5 mm criteria, respectively. Static deformations caused measured dose distribution shifts toward the phantom plunger. During the dynamic deformation experiment, the dosimeter that utilized beam gating showed an improvement in the γ pass rate compared to the dosimeter that did not. CONCLUSIONS: A deformable abdominal phantom apparatus which incorporates a deformable nPAG dosimeter was developed to test real-time IGRT systems and deformable dose accumulation algorithms. This apparatus was used to benchmark simple static irradiations in which it was found that measurements match well to the planned distributions. Deformable dose accumulation could be tested by directly measuring the shifts and blurring of the target dose due to interfractional organ deformation and motion. Dosimetric improvements were achieved from the motion management during intrafractional motion.

Risk factors for peripartum blood transfusion in South Africa: a case-control study.

BACKGROUND: Obstetric hemorrhage (OH) and access to peripartum blood transfusion remains a global health challenge. The rates of peripartum transfusion in South Africa exceed those in high-income countries despite comparable rates of OH. We sought to evaluate factors associated with peripartum transfusion. STUDY DESIGN AND METHODS: A case-control study was conducted at four large South African hospitals. Transfused peripartum women (cases) and nontransfused controls were stratum matched 1:2 by hospital and delivery date. Data on obstetric, transfusion, and human immunodeficiency virus (HIV) history were abstracted from medical records. Blood was obtained for laboratory evaluation. We calculated unadjusted and adjusted odds ratios (ORs) for transfusion using logistic regression. RESULTS: A total of 1200 transfused cases and 2434 controls were evaluated. Antepartum hemorrhage (OR, 197.95; 95% confidence interval [CI], 104.27-375.78), hemorrhage with vaginal delivery (OR, 136.46; 95% CI, 75.87-245.18), prenatal anemia (OR, 22.76; 95% CI, 12.34-41.93 for prenatal hemoglobin level < 7 g/dL), and failed access to prenatal care (OR, 6.71; 95% CI, 4.32-10.42) were the major risk factors for transfusion. Platelet (PLT) count (ORs, 4.10, 2.66, and 1.77 for ≤50 × 109 , 51 × 109 -100 × 109 , and 101 × 109 -150 × 109 cells/L, respectively), HIV infection (OR, 1.29; 95% CI, 1.02-1.62), and admitting hospital (twofold variation) were also associated with transfusion. Mode of delivery, race, age category, gravidity, parity, gestational age, and birthweight were not independently associated with transfusion. CONCLUSION: Major risk factors of peripartum transfusion in South Africa, namely, prenatal anemia and access to prenatal care, may be amenable to intervention. HIV infection and moderately low PLT count are novel risk factors that merit further investigation.

Development of a new enzyme immunoassay for improved detection of rotavirus in fecal specimens of vaccinated infants.

BACKGROUND: Group A rotavirus is the most common cause of acute diarrhea in young children worldwide. A simple and rapid enzyme immunoassay (EIA) has been commonly used to detect rotavirus infection and evaluate rotavirus vaccines. Currently licensed commercial EIA kits have low sensitivity. A more sensitive detection of rotavirus can improve rotavirus diagnostics and vaccine efficacy studies. OBJECTIVE: A biotin-avidin based sandwich EIA was developed and compared with commercial EIA kits for improved detection of viral shedding in fecal samples from infants who received human rotavirus vaccine Rotarix in Mexico. STUDY DESIGN: A monoclonal antibody (mAb: 1D4) specific to human rotavirus group antigen VP6 was prepared and used to develop a biotin-avidin based sandwich EIA. This EIA was employed to test 128 fecal samples from vaccinated infants, in comparison with two commercial EIA kits using RT-PCR as a reference. RESULTS: A new biotin-avidin based sandwich EIA showed specific reaction to group A rotaviruses, but not to other enteric viruses. This new EIA had a detection rate of 36.7% for rotavirus antigen shedding in fecal specimens, which was two times higher (16.4%, 18.0%) than those from two commercial EIA kits. CONCLUSION: The new EIA had specificity and higher sensitivity than commercial kits. This new EIA has the potential to detect rotavirus at lower concentration in clinical specimens and thus should be further evaluated as a more sensitive kit for use in diagnostics and vaccine efficacy and effectiveness studies.

Rotavirus antigen, cytokine, and neutralising antibody profiles in sera of children with and without HIV infection in Blantyre, Malawi.

BACKGROUND: Rotavirus and HIV infection are major causes of death among children in sub-Saharan Africa. A previous study reported no association between concomitant HIV infection and rotavirus disease severity among hospitalised children in Malawi. This study examined rotavirus antigenaemia and broader immune responses among HIV-infected and uninfected children. METHODS: Stored (-80°C), paired sera from acute and convalescent phases of Malawian children less than 5 years old, hospitalised for acute gastroenteritis in the primary study, collected from July 1997 to June 1999, were utilised. Among children older than 15 months, HIV infection was defined as the presence of HIV antibody in the blood, when confirmed by at least 2 established methods. For those younger than 15 months, nested polymerase chain reaction (PCR) amplification of proviral DNA was used for verification. All were followed for up to 4 weeks after hospital discharge. Rotavirus antigen levels in sera were measured with Premier™ Rotaclone® rotavirus enzyme immunoassay (EIA) kit. Acute-phase sera were examined for 17 cytokines, using Luminex fluorescent bead human cytokine immunoassay kit. Rotavirus-specific IgA and neutralising activity were determined by EIA and microneutralisation (MN) assay, respectively. Human strains and bovine-human reassortants were propagated in MA104 cells with serum-free Iscove's Modified Dulbecco's Medium (IMDM). Differences in results, from specimens with and without HIV infection, were analysed for statistical significance using the chi-square test. RESULTS: We detected rotavirus antigen in 30% of the HIV-infected and 21% HIV-uninfected, in the acute-phase sera. HIV-infected children developed slightly prolonged rotavirus antigenaemia compared to HIV-uninfected children. CONCLUSIONS: Rotavirus-specific IgA seroconversion rates and neutralising titres were similar in HIV-infected and HIV-uninfected children, thus, HIV infection had no major effect on immune responses to rotavirus infection.

Investigation of a Rotavirus Gastroenteritis Outbreak among Immunosuppressed Patients in a Hospital Setting.

Objective: Rotavirus (RV) is the most common cause of severe dehydrating diarrhoea in healthy infants and young children. The aims of this study were to investigate a RV outbreak in the pediatric hematology and oncology ward and to examine possible associations between immune status and RV infection. Patients and methods: Twenty-eight children (19 boys and 9 girls) who were hospitalized for treatment of hematological malignancy and solid organ tumor during the RV outbreak were enrolled in this study. Fourteen of the 28 patients developed RV gastroenteritis (GE) during the observation period. RV antigen and RV IgG and IgA were measured by enzyme-linked immunosorbent assays. RV G and P types were determined by reverse transcriptase-polymerase chain reaction. Results: Mean duration of RVGE in 14 patients was 13.9 days and mean severity score was 7.4. Two RV strains (G3P [8] and G2P [4]) were mainly circulating in the ward, which might result in the formation of a reassortant G2P [8] strain and mixed infection with G2+3P [8] in the immunocompromised patients. RV antigenemia was detected in 22 of the 28 patients (78.6%). RV-specific IgG titers in acute-phase sera of RVGE group were significantly lower than those in non-RVGE group (P=0.001). Mean age of the patients was significantly lower in RVGE group (5.5 ± 4.6 years) than non RVGE group (10.6 ± 4.5 years) (P=0.015). Conclusion: Our data demonstrate that host factors including age, underlying diseases, and immune status may be associated with the susceptibility of RV infection in immunocompromised patients at the time of the nosocomial infection.

Genomic Sequence of the First Porcine Rotavirus Group H Strain in the United States.

The genomic sequence of a rotavirus group H was identified in the intestine of a diarrheal pig in the United States, designated RVH/Pig-wt/USA/MN9.65/2008/GxP[x].

Rotavirus G and P types in children with acute diarrhea in Cairo, Egypt, 2011-2012.

BACKGROUND: The WHO estimated the annual rotavirus-related mortality among children below 5 years old in Egypt in 2004 to be 30 deaths per 100 000, or out of an estimated 2616 deaths, 3.9% were because of rotavirus infection. The aim of this article was to study the epidemiology and circulating genotypes of rotaviruses in Cairo from 2011 to 2012. MATERIALS AND METHODS: A total of 197 stool samples were collected from 130 inpatient children at the Cairo University Children Hospital and 67 outpatient children at the Al-Saff Children Clinic. The collected stool samples were then screened for rotavirus using enzyme immunoassay, followed by a screening for G-type and P-type using RT-PCR, and confirmation by sequence analysis. RESULTS: Rotavirus was detected in 39.1% (77/197) of the children, with a higher rate in inpatients (43.9%, 57/130) than in outpatients (29.9%, 20/67). There was an increase of rotavirus infection in the winter season. The majority of rotavirus cases (85.7%) occurred during the first year of life. The predominant genotypes identified during this study were G3P[8] (37.7%) and G1P[8] (19.5%), but uncommon genotypes G1P[6] (3.9%), G9P[6] (1.3%), G8P[14] (1.3%), and G12P[6] (2.6%) were also detected. CONCLUSION AND RECOMMENDATIONS: The change in genotype distribution, compared with previous studies, along with the high burden of rotavirus-associated diarrhea among Egyptian children below 2 years old, emphasizes the importance of continuing strain surveillance and the need of developing and introducing rotavirus vaccine in Egypt.

The impact of human immunodeficiency virus infection on obstetric hemorrhage and blood transfusion in South Africa.

BACKGROUND: Globally, as in South Africa, obstetric hemorrhage (OH) remains a leading cause of maternal mortality and morbidity. Although blood transfusion is critical to OH management, the incidence and predictors of transfusion as well as their relation to human immunodeficiency virus (HIV) infection are poorly described. STUDY DESIGN AND METHODS: A cross-sectional study was conducted of all peripartum patients at four major hospitals in South Africa (April to July 2012). Comprehensive clinical data were collected on patients who sustained OH and/or were transfused. Logistic regression was used to model risk factors for OH and transfusion. RESULTS: A total of 15,725 peripartum women were evaluated, of whom 3969 (25.2%) were HIV positive. Overall, 387 (2.5%) women sustained OH and 438 (2.8%) received transfusions, including 213 (1.4%) women with both OH and transfusion. There was no significant difference in OH incidence between HIV-positive (2.8%) and HIV-negative (2.3%) patients (adjusted odds ratio [OR], 0.95; 95% confidence interval [CI], 0.72-1.25). In contrast, the incidence of blood transfusion was significantly higher in HIV-positive (3.7%) than in HIV-negative (2.4%) patients (adjusted OR, 1.52; 95% CI, 1.14-2.03). Other risk factors for transfusion included OH, low prenatal hemoglobin, the treating hospital, lack of prenatal care, and gestational age of not more than 34 weeks. CONCLUSION: In the South African obstetric setting, the incidence of peripartum blood transfusion is significantly higher than in the United States and other high-income countries while OH incidence is similar. While OH and prenatal anemia are major predictors of transfusion, HIV infection is a common and independent contributing factor.

Pharmacokinetics of efavirenz and treatment of HIV-1 among pregnant women with and without tuberculosis coinfection.

BACKGROUND: Pregnancy and tuberculosis treatment or prophylaxis can affect efavirenz pharmacokinetics, maternal human immunodeficiency virus type 1 (HIV-1) treatment outcomes, and mother-to-child transmission (MTCT) risk. METHODS: We evaluated a prospective cohort of pregnant, HIV-infected women with and without tuberculosis in Soweto, South Africa. Pharmacokinetic sampling was performed at gestation week 37 and during the postpartum period. Efavirenz trough concentrations (Cmin) were predicted using population pharmacokinetic models. HIV-viral load was measured at delivery for mothers and at 6 weeks of age for infants. RESULTS: Ninety-seven women participated; 44 had tuberculosis. Median efavirenz Cmin during pregnancy was 1.35 µg/mL (interquartile range [IQR], 0.90-2.07 µg/mL; 27% had an efavirenz Cmin of < 1 µg/mL), compared with a median postpartum value of 2.00 µg/mL (IQR, 1.40-3.59 µg/mL; 13% had an efavirenz Cmin of < 1 µg/mL). A total of 72% of pregnant women with extensive CYP2B6 genotypes had an efavirenz Cmin of <1 µg/mL. Rifampin did not reduce the efavirenz Cmin. Isoniazid (for prophylaxis or treatment), though, reduced the rate of efavirenz clearance. At delivery, median durations of ART were 13 weeks (IQR, 9-18 weeks) and 21 weeks (IQR, 13-64 weeks) for women with and those without tuberculosis, respectively; 55% and 83%, respectively, had a viral load of <20 copies/mL (P = .021). There was 1 case of MTCT. CONCLUSIONS: Pregnancy increased the risk of low efavirenz concentrations, but MTCT was rare. A detectable HIV-viral load at delivery was more common among pregnant women with tuberculosis, in whom ART was generally initiated later.

Genetic analysis of G12P[8] rotaviruses detected in the largest U.S. G12 genotype outbreak on record.

In 2006-07, 77 cases of gastroenteritis in Rochester, NY, USA were associated with rotavirus genotype G12P[8]. Sequence analysis identified a high degree of genetic relatedness among the VP7 and VP4 genes of the Rochester G12P[8] strains and between these strains and currently circulating human G12P[8] strains. Out of 77 samples, two and seven unique nucleotide sequences were identified for VP7 and VP4 genes, respectively. Rochester strain VP7 genes were found to occupy the G12-III lineage and VP4 genes clustered within the P[8]-3 lineage. Six strains contained non-synonymous nucleotide substitutions that produced amino acid changes at 6 sites in the VP8(∗) region of the VP4 gene. Two sites (amino acids 242 and 246) were located in or near a described trypsin cleavage site. Selection analyses identified one positively selected VP7 site (107) and strong purifying selection at 58 sites within the VP7 gene as well as 2 of the 6 variant sites (79 and 218) in VP4.

Immunological effects of the TGFß-blocking antibody GC1008 in malignant pleural mesothelioma patients.

We evaluated a neutralizing anti-TGFß antibody (GC1008) in cancer patients with malignant pleura mesothelioma (MPM). The goal of this study was to assess immunoregulatory effects in relation to clinical safety and clinical response. Patients with progressive MPM and 1-2 prior systemic therapies received GC1008 at 3mg/kg IV over 90 min every 21 d as part of an open-label, two-center Phase II trial. Following TGFß blockade therapy, clinical safety and patient survival were monitored along with the effects of anti-TGFß antibodies on serum biomarkers and peripheral blood mononuclear cells (PBMC). Although designed as a larger trial, only 13 patients were enrolled when the manufacturer discontinued further development of the antibody for oncology indications. All participants tolerated therapy. Although partial or complete radiographic responses were not observed, three patients showed stable disease at 3 mo. GC1008 had no effect in the expression of NK, CD4+, or CD8+ T cell activating and inhibitory markers, other than a decrease in the expression of 2B4 and DNAM-1 on NK cells. However, serum from 5 patients showed new or enhanced levels of antibodies against MPM tumor lysates as measured by immunoblotting. Patients who produced anti-tumor antibodies had increased median overall survival (OS) (15 vs 7.5 mo, p < 0.03) compared with those who did not. To our knowledge, these data represent the first immune analysis of TGFß- blockade in human cancer patients.

A review of the use of blood and blood products in HIV-infected patients.

Despite numerous publications on the appropriate use of blood and blood products, few specifically consider the role of transfusion in the management of HIV. This review is a synthesis of conditions encountered in the management of HIV-infected patients where the transfusion of blood or blood products may be indicated. A consistent message emerging from the review is that the principles of transfusion medicine do not differ between HIV-negative and -positive patients. The aim of the review is to provide clinicians with a practical and succinct overview of the haematological abnormalities and clinical circumstances most commonly encountered in the HIV setting, while focusing on the rational and appropriate use of blood and blood products for HIV patients. Important ethical considerations in dealing with both the collection and transfusion blood and blood products in the HIV era have also been addressed.

Detection of fecal shedding of rotavirus vaccine in infants following their first dose of pentavalent rotavirus vaccine.

Studies on rotavirus vaccine shedding and its potential transmission within households including immunocompromised individuals are needed to better define the potential risks and benefits of vaccination. We examined fecal shedding of pentavalent rotavirus vaccine (RV5) for 9 days following the first dose of vaccine in infants between 6 and 12 weeks of age. Rotavirus antigen was detected by enzyme immunoassay (EIA), and vaccine-type rotavirus was identified by nucleotide sequencing based on genetic relatedness to the RV5 VP6 gene. Stool from 22 (21.4%) of 103 children contained rotavirus antigen-positive specimens on ≥ 1 post-vaccination days. Rotavirus antigen was detected as early as post-vaccination day 3 and as late as day 9, with peak numbers of shedding on post-vaccination days 6 through 8. Vaccine-type rotavirus was detected in all 50 antigen-positive specimens and 8 of 8 antigen-negative specimens. Nine (75%) of 12 EIA-positive and 1 EIA-negative samples tested culture-positive for vaccine-type rotavirus. Fecal shedding of rotavirus vaccine virus after the first dose of RV5 occurred over a wide range of post-vaccination days not previously studied. These findings will help better define the potential for horizontal transmission of vaccine virus among immunocompromised household contacts of vaccinated infants for future studies.

United States rotavirus strain surveillance from 2005 to 2008: genotype prevalence before and after vaccine introduction.

BACKGROUND: A live, attenuated rotavirus vaccine, RotaTeq®, was approved in 2006 for immunization of infants in the United States. To monitor the distribution of rotavirus genotypes before and after vaccine introduction, the Centers for Disease Control and Prevention conducted strain surveillance with the National Rotavirus Strain Surveillance System. METHODS: Over 3 rotavirus seasons, 2005-2006, 2006-2007, and 2007-2008, National Rotavirus Strain Surveillance System laboratories collected rotavirus-positive stool specimens and submitted them to the Centers for Disease Control and Prevention. Rotavirus strains were G- and P-genotyped by multiplex reverse transcription-polymerase chain reaction or nucleotide sequencing. RESULTS: During 2005-2006 and 2006-2007 seasons, G1 was the dominant G-type but in the 2007-2008 season, G3 replaced G1 as the most frequently detected strain. Four genotypes, G1P[8], G2P[4], G3P[8], and G9P[8] were detected in every season. Uncommon strains observed during the study period were G2P[8], G1P[6], G2P[6], G4P[6], G1P[4], G3P[9], G12P [6], and G12P[8]. The mean age of rotavirus cases in the 2007-2008 season increased significantly in patients less than 3 years old compared with the 2 previous seasons. CONCLUSIONS: : The increased overall prevalence of G3P [8] strains in 2007-2008, the first rotavirus season with reasonable rotavirus vaccine coverage, was consistent with Australian reports of G3 dominance following RotaTeq introduction. However, these strain changes in both countries have occurred in the context of large declines in severe rotavirus disease and we cannot rule out that they are simply the result of naturally occurring changes in rotavirus strain prevalence. These findings underscore the need for careful monitoring of strains to assess possible vaccine pressure-induced changes and vaccine effectiveness against various rotavirus genotypes.

Detection of rotavirus antigenemia in routinely obtained serum specimens to augment surveillance and vaccine effectiveness evaluations.

BACKGROUND: : Antigenemia is common among children with rotavirus disease. Because obtaining stool specimens is cumbersome, we evaluated whether detection of antigenemia in sera obtained during routine clinical practice could augment rotavirus surveillance to assess the effect of vaccination. METHODS: : We determined the sensitivity, specificity, and positive and negative predictive values of serum/plasma rotavirus antigen detection using fecal antigen positivity as the gold standard. Fecal specimens obtained by active surveillance and residual serum/plasma specimens obtained during routine clinical testing from children 15 days to 23 months of age presenting with acute gastroenteritis (AGE) to a children's hospital in Houston were tested for rotavirus using a commercially available enzyme immunoassay. Using case-control methods, we compared vaccine effectiveness (VE) using cases identified through serum/plasma testing versus stool testing. RESULTS: : Of the 205 AGE patients with fecal specimens, 71 (35%) had a serum/plasma sample available. Among these 71 children, antigenemia was detected in 22 of 29 with rotavirus-positive fecal specimens (sensitivity = 75%; 95% confidence interval [CI] = 60%-91%) versus 2 of 42 children with rotavirus-negative fecal specimens (specificity = 95%; 95% CI = 89%-100%). The positive and negative predictive values of rotavirus antigenemia were 92% (95% CI = 81%-100%) and 85% (95% CI = 75%-95%), respectively. Thirty-four of 195 children with AGE without fecal specimens had serum/plasma available; 10 (29%) had rotavirus antigenemia. Three-dose VE using cases identified through serum/plasma testing was similar (VE = 84%; 95% CI = 25%-96%) to that using cases identified though fecal testing (VE = 85%; 95% CI = 55%-95%). CONCLUSIONS: : Detection of antigenemia in routinely collected serum/plasma could augment identification of rotavirus disease for postlicensure evaluation of impact and effectiveness of rotavirus vaccination.