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1.
Transfusion ; 60(3): 479-487, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31909499

RESUMO

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.


Assuntos
Anemia/terapia , Transfusão de Sangue/métodos , Hemorragia/terapia , Adulto , Estudos Transversais , Feminino , Idade Gestacional , Infecções por HIV , Humanos , Gravidez , Prevalência , África do Sul , Reação Transfusional
2.
J Appl Clin Med Phys ; 20(8): 122-133, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31355997

RESUMO

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.


Assuntos
Abdome/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Radiometria/instrumentação , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Simulação por Computador , Humanos , Neoplasias/radioterapia , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Tomografia Computadorizada por Raios X/métodos
3.
Transfusion ; 58(9): 2149-2156, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29989178

RESUMO

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.


Assuntos
Transfusão de Sangue/estatística & dados numéricos , Hemorragia Pós-Parto/terapia , Adolescente , Adulto , Anemia/epidemiologia , Peso ao Nascer , Estudos de Casos e Controles , Cesárea , Feminino , Idade Gestacional , Infecções por HIV/epidemiologia , Acessibilidade aos Serviços de Saúde , Humanos , Recém-Nascido , Razão de Chances , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Hemorragia Pós-Parto/epidemiologia , Gravidez , Complicações Hematológicas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Cuidado Pré-Natal , Fatores de Risco , África do Sul/epidemiologia , Adulto Jovem
4.
J Infect Dis ; 211(2): 197-205, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25081933

RESUMO

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.


Assuntos
Fármacos Anti-HIV/farmacocinética , Benzoxazinas/farmacocinética , Infecções por HIV/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adolescente , Adulto , Alcinos , Fármacos Anti-HIV/administração & dosagem , Benzoxazinas/administração & dosagem , Estudos de Coortes , Coinfecção/tratamento farmacológico , Coinfecção/virologia , Ciclopropanos , Feminino , Infecções por HIV/complicações , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Humanos , Plasma/química , Plasma/virologia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Estudos Prospectivos , África do Sul , Tuberculose/complicações , Carga Viral , Adulto Jovem
5.
Transfusion ; 55(7): 1675-84, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25773233

RESUMO

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.


Assuntos
Transfusão de Sangue , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/terapia , Adolescente , Adulto , Estudos Transversais , Feminino , Infecções por HIV/sangue , Humanos , Incidência , Hemorragia Pós-Parto/sangue , Hemorragia Pós-Parto/virologia , Gravidez , Fatores de Risco , África do Sul/epidemiologia
6.
J Am Vet Med Assoc ; 261(7): 1028-1036, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913393

RESUMO

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.


Assuntos
Doenças do Gato , Doenças do Cão , Clínicos Gerais , Médicos Veterinários , Animais , Gatos , Cães , Humanos , Inquéritos e Questionários , Educação Continuada
7.
South Afr J HIV Med ; 13(2): 87-104, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28479876

RESUMO

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.

8.
Brachytherapy ; 21(3): 354-361, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35123888

RESUMO

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.


Assuntos
Braquiterapia , Radioisótopos de Irídio , Braquiterapia/métodos , Calibragem , Humanos , Radiometria/métodos
9.
J Am Vet Med Assoc ; 260(13): 1704-1710, 2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35905150

RESUMO

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.


Assuntos
Clínicos Gerais , Médicos Veterinários , Animais , Humanos , Comunicação , Inquéritos e Questionários , Equipe de Assistência ao Paciente
10.
J Infect Dis ; 200 Suppl 1: S99-S105, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19817622

RESUMO

BACKGROUND: Rotavirus vaccine was recommended for routine use among US infants in 2006. To provide prevaccine data, we conducted strain surveillance for 9 consecutive seasons during 1996-2005. METHODS: Using reverse-transcriptase polymerase chain reaction genotyping and nucleotide sequencing, we determined P/G genotypes of >3100 rotavirus strains collected in up to 12 cities each year from different US regions. RESULTS: The most prevalent strain globally, P[8] G1, was the most prevalent each year in the United States (overall, 78.5% of strains; range, 60.0%-93.9%), and 9.2% of the samples were P[4] G2, 3.6% were P[8] G9, 1.7% were P[8] G3, and 0.8% were P[8] G4. Genotype P[6] G9, which emerged in 1995, was detected continuously for several seasons (from 1996-1997 to 2000-2001, 0.2%-5.4%) but was not identified in the subsequent 4 seasons. Single or a few detections of rare genotypes (eg, P[6] G12, P[9] G6, and P[9] G3) were observed during several rotavirus seasons at frequencies of 0.5%-1.7% and, overall, comprised 0.6% of all the samples from the entire surveillance period. Several globally common strains in addition to G1, especially G2 and G9, circulated at high prevalence (33%-62%) in some cities during certain years. CONCLUSIONS: Almost 85% of strains during 1996-2005 had either a G or P antigen that is present in both RotaTeq (Merck) and Rotarix (GlaxoSmithKline). Monitoring of strains after introduction of rotavirus vaccines is important.


Assuntos
Vacinas contra Rotavirus/imunologia , Rotavirus/classificação , Rotavirus/isolamento & purificação , Pré-Escolar , Genótipo , Humanos , Lactente , Fatores de Tempo , Estados Unidos
11.
PLoS One ; 15(12): e0244498, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33373390

RESUMO

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.


Assuntos
Genoma Viral/genética , Infecções por Rotavirus/veterinária , Rotavirus/genética , Sus scrofa/virologia , Doenças dos Suínos/virologia , Animais , Evolução Molecular , Metagenômica , Filogenia , Rotavirus/isolamento & purificação , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/virologia , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/prevenção & controle , Estados Unidos , Viroma/genética , Sequenciamento Completo do Genoma
12.
Emerg Infect Dis ; 15(1): 83-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19116059

RESUMO

We report characterization of a genotype G5P[7] human rotavirus (HRV) from a child in Cameroon who had diarrhea. Sequencing of all 11 gene segments showed similarities to > or =5 genes each from porcine and human rotaviruses. This G5P[7] strain exemplifies the importance of heterologous animal rotaviruses in generating HRV genetic diversity through reassortment.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Animais , Camarões/epidemiologia , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Vírus Reordenados/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Análise de Sequência de DNA , Suínos/virologia , Proteínas não Estruturais Virais/genética , Proteínas Estruturais Virais/genética
13.
Arch Virol ; 154(11): 1823-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19763776

RESUMO

The Pan-American Health Organization established a rotavirus pre-vaccination disease burden and strain surveillance network in Latin America and the Caribbean in 2004. During strain surveillance in Ecuador in 2005-2006, a rare rotavirus genotype, G11P[6], was detected among common strains. Sequencing and phylogenetic analysis of this strain identified a novel lineage of the G11 VP7 gene, most closely related to A253 (91.8% nt identity), a porcine rotavirus strain identified in Venezuela. Most genes of this strain clustered with porcine, human-porcine or bovine-porcine reassortant strains; only VP6 and perhaps NSP2 genes were more closely related to cognate genes of human rotaviruses. Thus, this strain was likely generated by gene reassortment between porcine and human parental strains. Our study provides further evidence that animal rotaviruses play an important role in genetic and antigenic diversity of rotaviruses pathogenic for humans.


Assuntos
Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Animais , Equador/epidemiologia , Feminino , Regulação Viral da Expressão Gênica/fisiologia , Humanos , Lactente , Filogenia , Vigilância da População , Infecções por Rotavirus/epidemiologia , Suínos , Proteínas Virais/genética , Proteínas Virais/metabolismo
14.
JAMA ; 301(21): 2243-51, 2009 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-19491186

RESUMO

CONTEXT: Pentavalent rotavirus vaccine (RV5), a live, oral attenuated vaccine, prevented 98% of severe rotavirus diarrhea in a trial conducted mainly in Finland and the United States. Nicaragua introduced RV5 in 2006, providing the first opportunity to assess the association between vaccination and rotavirus disease in a developing country. OBJECTIVE: To assess the association between RV5 vaccination and subsequent rotavirus diarrhea requiring overnight admission or intravenous hydration. DESIGN, SETTING, AND PARTICIPANTS: Case-control evaluation in 4 hospitals in Nicaragua from June 2007 to June 2008. Cases were children age-eligible to receive RV5 who were admitted or required intravenous hydration for laboratory-confirmed rotavirus diarrhea. For each case (n = 285), 1 to 3 neighborhood (n = 840) and hospital (n = 690) controls were selected. MAIN OUTCOME MEASURES: Primary outcome was the association of RV5 and rotavirus diarrhea requiring overnight admission or intravenous hydration in the emergency department. Secondary analysis further classified disease as severe and very severe. We computed the matched odds ratio of vaccination in cases vs controls. Vaccine effectiveness was estimated using the formula 1 - matched odds ratio x 100%. RESULTS: Of the 285 rotavirus cases, 265 (93%) required hospitalization; 251 (88%) received intravenous hydration. A single rotavirus strain (G2P[4]) was identified in 88% of the cases. Among cases and controls, respectively, 18% and 12% were unvaccinated, 12% and 15% received 1 dose of RV5, 15% and 17% received 2 doses, and 55% and 57% received 3 doses. Vaccination with 3 doses was associated with a lower risk of rotavirus diarrhea requiring overnight admission or intravenous hydration (odds ratio [OR], 0.54; 95% confidence interval [CI], 0.36-0.82). Of the 285 rotavirus cases, 191 (67%) were severe and 54 (19%) were very severe. A progressively lower risk of severe (OR, 0.42; 95% CI, 0.26-0.70) and very severe rotavirus diarrhea (OR, 0.23; 95% CI, 0.08-0.61) was observed after RV5 vaccination. Thus, effectiveness of 3 doses of RV5 against rotavirus disease requiring admission or treatment with intravenous hydration was 46% (95% CI, 18%-64%); against severe rotavirus diarrhea, 58% (95% CI, 30%-74%); and against very severe rotavirus diarrhea, 77% (95% CI, 39%-92%). CONCLUSION: Vaccination with RV5 was associated with a lower risk of severe rotavirus diarrhea in children younger than 2 years in Nicaragua but to a lesser extent than that seen in clinical trials in industrialized countries.


Assuntos
Países em Desenvolvimento , Diarreia Infantil/virologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Diarreia Infantil/epidemiologia , Diarreia Infantil/prevenção & controle , Feminino , Hidratação , Hospitalização , Humanos , Programas de Imunização , Esquemas de Imunização , Lactente , Modelos Logísticos , Masculino , Nicarágua , Infecções por Rotavirus/epidemiologia , Vacinação , Vacinas Atenuadas/administração & dosagem
15.
J Clin Microbiol ; 46(5): 1842-3, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18353936

RESUMO

Rates of detection of rotavirus were compared by diagnostic assay and specimen type. For bulk stools, rates of detection by reverse transcriptase PCR (RT-PCR) and enzyme immunoassay (EIA) were similar, but 18% of healthy controls tested positive by RT-PCR. Testing of bulk stools by EIA appears to be optimum for rotavirus surveillance.


Assuntos
Programas de Rastreamento/métodos , Infecções por Rotavirus/diagnóstico , Rotavirus/isolamento & purificação , Virologia/métodos , Pré-Escolar , Fezes/virologia , Humanos , Técnicas Imunoenzimáticas/métodos , Lactente , Recém-Nascido , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
16.
J Med Virol ; 80(8): 1489-96, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18551614

RESUMO

A sensitive and specific real-time RT-PCR assay to detect rotavirus in stool samples was optimized and validated using a wide range of rotavirus genotypes. The target of the original TaqMan(R) assay is an 87 bp fragment of the highly conserved non-structural protein 3 (NSP3) gene. Here we modified the original assay by introducing degeneracy into the forward primer to account for sequence variation between rotavirus genotypes, added four nucleotides at the 3' end of the reverse primer to reduce its stability, and modified the probe label. Amplification and detection conditions were optimized using purified dsRNA from two cultivated strains. The limit of detection of the modified assay was calculated to be approximately 44 genome copies per reaction. To validate the reactivity of the assay, 103 archived RNAs that had been extracted from stools and genotyped during routine U.S. surveillance were tested. Samples were selected to represent both rare and common genotypes that have been detected in U.S. children. Nine genotypes known to be circulating in the United States were detected by the real-time assay demonstrating broad reactivity. In addition, other enteric viruses were not detected demonstrating that the assay is specific for rotavirus and does not cross-react with other viruses potentially present in stool samples. This real-time assay is an important addition to the arsenal of molecular tools available to quickly identify rotavirus in stool samples during routine surveillance.


Assuntos
Diarreia/virologia , Fezes/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Infecções por Rotavirus/virologia , Rotavirus/isolamento & purificação , Primers do DNA , Genótipo , Humanos , RNA Viral/análise , RNA Viral/isolamento & purificação , Rotavirus/classificação , Rotavirus/genética , Sensibilidade e Especificidade , Proteínas não Estruturais Virais/genética
17.
J Clin Virol ; 99-100: 44-49, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29306770

RESUMO

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.


Assuntos
Fezes/virologia , Técnicas Imunoenzimáticas , Infecções por Rotavirus/diagnóstico , Vacinas contra Rotavirus/administração & dosagem , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Proteínas do Capsídeo/imunologia , Humanos , Técnicas Imunoenzimáticas/normas , Lactente , México , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Malawi Med J ; 29(1): 24-28, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28567192

RESUMO

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.


Assuntos
Anticorpos Neutralizantes/sangue , Citocinas/sangue , Gastroenterite/virologia , Infecções por HIV/complicações , Reação em Cadeia da Polimerase/métodos , Infecções por Rotavirus/diagnóstico , Rotavirus/imunologia , Viremia/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Bovinos , Feminino , Gastroenterite/diagnóstico , Humanos , Lactente , Recém-Nascido , Malaui , Masculino , Rotavirus/isolamento & purificação , Infecções por Rotavirus/sangue , Infecções por Rotavirus/fisiopatologia
19.
J Immunol Tech Infect Dis ; 6(1)2017 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35923213

RESUMO

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.

20.
Genome Announc ; 4(2)2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26966223

RESUMO

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].

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