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1.
Front Microbiol ; 15: 1374568, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618485

RESUMO

CrAssphages are human gut bacteriophages with potential use as an indicator of human fecal contamination in water and other environmental systems. We determined the prevalence and abundance of crAssphages in water, food, and fecal samples and compared these estimates with the prevalence of norovirus. Samples were tested using two crAssphage-specific qPCR assays (CPQ056 and TN201-203) and for norovirus using TaqMan realtime RT-PCR. CrAssphage was detected in 40% of human fecal specimens, 61% of irrigation water samples, 58.5% of stream water samples, and 68.5% of fresh leafy greens samples. Interestingly, across all sample categories, crAssphage concentrations were 2-3 log10 higher than norovirus concentrations. The correlation of detection of crAssphage and norovirus was significant for the irrigation water samples (r = 0.74, p = 7.4e-06). Sequences obtained from crAssphage positive samples from human fecal and stream water samples phylogenetically clustered with genotype I crAssphages, whereas sequences derived from irrigation water samples clustered differently from other genotypes. Our data show that crAssphages were prevalent in norovirus-positive water samples and in fresh leafy green samples, there was a strong correlation between the presence of crAssphage and norovirus. CrAssphage genomic copies were consistently higher than norovirus copies in all sample types. Overall, our findings suggest that crAssphages could be used as reliable indicators to monitor fecal-borne virus contamination within the food safety chain.

2.
J Anim Sci Technol ; 65(4): 748-758, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37970510

RESUMO

This study was conducted to investigate the change in activity and mounting behavior in Hanwoo (Korean Native Cattle) during the peri-estrus period and its application to estrus detection. A total of 20 Hanwoo cows were fitted with a neck-collar accelerometer device, which measured the location and acceleration of cow movements and recorded the number of instances of mounting behavior by the altitude data. The data were analyzed in three periods (24-, 6-, and 2-h periods). Blood samples were collected for 5 days after the prostaglandin F2α (PGF2α) injection, and the concentrations of estradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone were determined by enzyme-linked immunosorbent assays. Activity and mounting behavior recorded over 2-h periods significantly increased as estrus approached and were more efficient at detecting estrus than over 24- and 6-h periods (p < 0.05). Endocrine patterns did not differ with the variation of individual cows during the peri-estrus period (p > 0.05). Activity was selected as the best predictor through stepwise discriminant analysis. However, activity alone is not enough to detect estrus. We suggest that a combination of activity and mounting behavior may improve estrus detection efficiency in Hanwoo. Further research is necessary to validate the findings on a larger sample size.

3.
Animals (Basel) ; 13(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570216

RESUMO

Chronic stress in the dairy cattle industry has negative impacts on animal health, productivity, and welfare. It has been confirmed that cortisol transfers to milk and resists the high temperature during milk processing. This study evaluated the relationship between the milk cortisol concentration (MCC) in commercial milk products and the temperature-humidity index (THI) at the time of milk production. Eleven commercially produced pasteurized and sterilized milk products, purchased in Chuncheon, Korea, with production dates ranging from July to October 2021 were analyzed. The MCC was extracted using diethyl ether and analyzed using an enzyme immunoassay. The average THI values based on microclimate data provided by the Korea Meteorological Administration were 77 ± 0.8, 75 ± 1.4, 69 ± 1.4, and 58 ± 1.8, in July, August, September, and October, respectively. The average MCC levels were 211.9 ± 95.1, 173.5 ± 63.8, 109.6 ± 53.2, and 106.7 ± 33.7 pg/mL in July, August, September, and October, respectively. The MCC in July was higher than in August, September, and October (p < 0.05), while it was lower in September and October than in August (p < 0.05). Significant variations in the MCC were observed in commercial milk products across the four production months (p < 0.05), except for two milk products. Overall, monitoring the cortisol residue in commercial dairy milk products can be an alternative indicator of stress in dairy cattle of farms.

4.
J Anim Sci Technol ; 65(2): 459-472, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37093900

RESUMO

Korea is currently developing country-specific emission factors to support the 2050 zero-carbon campaign. Dairy cattle represent one of the largest livestock industries in Korea, and the industry is estimated to continue increasing because of an increase in milk demand. However, country-specific emission factors for dairy cattle are currently only available for calculating methane (CH4) emissions from enteric fermentation. Two experiments were conducted to evaluate CH4 and nitrous oxide (N2O) fluxes from sawdust-bedded barn in dairy cow and steer, as well as dairy cattle manure composting lots. The greenhouse gas (GHG) fluxes were quantified using the open-chamber method and gas chromatography. CH4 fluxes from steer, dairy cow, and manure compost were 27.88 ± 5.84, 36.12 ± 10.85, and 259.44 ± 61.78 µg/head/s, respectively. N2O fluxes from steer, dairy cow, and manure compost were 14.04 ± 1.27, 4.11 ± 1.57, and 3.97 ± 1.08 µg/head/s, respectively. The result of this study can be used to construct country-specific data for GHG emissions from manure management. Thus, the application of mitigation strategies can be prioritized based on the GHG profile and targeted source.

5.
PLoS One ; 17(10): e0274946, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36215247

RESUMO

While risk of fomite transmission of SARS-CoV-2 is considered low, there is limited environmental data within households. This January-April 2021 investigation describes frequency and types of surfaces positive for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction (RT-PCR) among residences with ≥1 SARS-CoV-2 infection, and associations of household characteristics with surface RT-PCR and viable virus positivity. Of 1232 samples from 124 households, 27.8% (n = 342) were RT-PCR positive with nightstands (44.1%) and pillows (40.9%) most frequently positive. SARS-CoV-2 lineage, documented household transmission, greater number of infected persons, shorter interval between illness onset and sampling, total household symptoms, proportion of infected persons ≤12 years old, and persons exhibiting upper respiratory symptoms or diarrhea were associated with more positive surfaces. Viable virus was isolated from 0.2% (n = 3 samples from one household) of all samples. This investigation suggests that while SARS-CoV-2 on surfaces is common, fomite transmission risk in households is low.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Teste para COVID-19 , Criança , Colorado , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética
6.
J Anim Sci Technol ; 64(4): 770-781, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35969695

RESUMO

Meteorological disasters caused by climate change like heat, cold waves, and unusually long rainy seasons affect the milk productivity of cows. Studies have been conducted on how milk productivity and milk compositions change due to heat stress (HS). However, the estimation of losses in milk production due to HS and hereby environmental impacts of greenhouse gas (GHG) emissions are yet to be evaluated in Korean dairy farms. Dairy milk production and milk compositions data from March to October 2018, provided by the Korea Dairy Committee (KDC), were used to compare regional milk production with the temperature-humidity index (THI). Raw data for the daily temperature and relative humidity in 2018 were obtained from the Korea Meteorological Administration (KMA). This data was used to calculate the THI and the difference between the maximum and minimum temperature changing rate, as the average daily temperature range, to show the extent to which the temperature gap can affect milk productivity. The amount of milk was calculated based on the price of 926 won/kg from KDC. The results showed that the average milk production rate was the highest within the THI range 60-73 in three regions in May: Chulwon (northern region), Hwasung (central region), and Gunwi (southern region). The average milk production decreased by 4.96 ± 1.48% in northern region, 7.12 ± 2.36% in central region, and 7.94 ± 2.57% in southern region from June to August, which had a THI range of 73 or more, when compared to May. Based on the results, the level of THI should be maintained like May. If so, the farmers can earn a profit of 9,128,730 won/farm in northern region, 9,967,880 won/farm in central region, and 12,245,300 won/farm in southern region. Additionally, the average number of cows raised can be reduced by 2.41 ± 0.35 heads/farm, thereby reducing GHG emissions by 29.61 ± 4.36 kg CO2eq/day on average. Overall, the conclusion suggests that maintaining environmental conditions in the summer that are similar to those in May is necessary. This knowledge can be used for basic research to persuade farmers to change farm facilities to increase the economic benefits and improve animal welfare.

7.
J Appl Microbiol ; 132(6): 4289-4299, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35279925

RESUMO

AIMS: To determine the efficacy of a panel of nine EPA-registered disinfectants against two human norovirus (HuNoV) surrogates (feline calicivirus [FCV] and Tulane virus [TuV]) and Clostridioides difficile endospores. METHODS AND RESULTS: Nine EPA-registered products, five of which contained H2 O2 as active ingredient, were tested against infectious FCV, TuV and C. difficile endospores using two ASTM methods, a suspension and carrier test. Efficacy claims against FCV were confirmed for 8 of 9 products. The most efficacious product containing H2 O2 as ingredient achieved a >5.1 log reduction of FCV and >3.1 log reduction of TuV after 5 min, and >6.0 log reduction of C. difficile endospores after 10 min. Of the five products containing H2 O2 , no strong correlation (R2  = 0.25, p = 0.03) was observed between disinfection efficacy and H2 O2 concentration. Addition of 0.025% ferrous sulphate to 1% H2 O2 solution improved efficacy against FCV, TuV and C. difficile. CONCLUSION: Disinfectants containing H2 O2 are the most efficacious disinfection products against FCV, TuV and C. difficile endospores. Product formulation, rather than the concentration of H2 O2 in a product, impacts the efficacy of a disinfection product. SIGNIFICANCE AND IMPACT OF STUDY: H2 O2 -based disinfectants are efficacious against surrogate viruses for HuNoV and C. difficile endospores.


Assuntos
Calicivirus Felino , Clostridioides difficile , Desinfetantes , Norovirus , Animais , Gatos , Clostridioides , Desinfetantes/farmacologia , Humanos , Esporos Bacterianos
8.
Am J Infect Control ; 50(3): 289-294, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35184878

RESUMO

BACKGROUND: Norovirus and C. difficile are associated with diarrheal illnesses and deaths in long-term care (LTC) facilities and can be transmitted by contaminated environmental surfaces. Hygienic monitoring tools such as adenosine triphosphate (ATP) bioluminescence and indicators of fecal contamination can help to identify LTC facility surfaces with cleaning deficiencies. METHODS: High-touch surfaces in 11 LTC facilities were swabbed and tested for contamination by norovirus, a fecal indicator virus, crAssphage, and ATP which detects organic debris. High levels of contamination were defined as log ATP relative light unit values or crAssphage log genomic copy values in the 75th percentile of values obtained from each facility. RESULTS: Over 90% of surfaces tested positive for crAssphage or gave failing ATP scores. Norovirus contamination was not detected. Handrails, equipment controls, and patient beds were 4 times more likely than other surfaces or locations to have high levels of crAssphage. Patient bed handrails and tables and chairs in patient lounges had high levels of both ATP and crAssphage. CONCLUSIONS: Surfaces with high levels of ATP and crAssphage were identified. Quantifying levels of contamination longitudinally and before and after cleaning might enhance infection prevention and control procedures for reducing diarrheal illnesses in LTC facilities.


Assuntos
Clostridioides difficile , Norovirus , Trifosfato de Adenosina/análise , Monitoramento Ambiental , Humanos , Assistência de Longa Duração , Casas de Saúde
9.
Artigo em Inglês | MEDLINE | ID: mdl-34360477

RESUMO

SARS-CoV-2 transmission from contaminated surfaces, or fomites, has been a concern during the COVID-19 pandemic. Households have been important sites of transmission throughout the COVID-19 pandemic, but there is limited information on SARS-CoV-2 contamination of surfaces in these settings. We describe environmental detection of SARS-CoV-2 in households of persons with COVID-19 to better characterize the potential risks of fomite transmission. Ten households with ≥1 person with laboratory-confirmed COVID-19 and with ≥2 members total were enrolled in Utah, U.S.A. Nasopharyngeal and anterior nasal swabs were collected from members and tested for the presence of SARS-CoV-2 by RT-PCR. Fifteen surfaces were sampled in each household and tested for presence and viability of SARS-CoV-2. SARS-CoV-2 RNA was detected in 23 (15%) of 150 environmental swab samples, most frequently on nightstands (4/6; 67%), pillows (4/23; 17%), and light switches (3/21; 14%). Viable SARS-CoV-2 was cultured from one sample. All households with SARS-CoV-2-positive surfaces had ≥1 person who first tested positive for SARS-CoV-2 ≤ 6 days prior to environmental sampling. SARS-CoV-2 surface contamination occurred early in the course of infection when respiratory transmission is most likely, notably on surfaces in close, prolonged contact with persons with COVID-19. While fomite transmission might be possible, risk is low.


Assuntos
COVID-19 , SARS-CoV-2 , Fômites , Humanos , Pandemias , RNA Viral
10.
Emerg Infect Dis ; 26(8): 1731-1739, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32511090

RESUMO

CrAssphage is a recently discovered human gut-associated bacteriophage. To validate the potential use of crAssphage for detecting human fecal contamination on environmental surfaces and hands, we tested stool samples (n = 60), hand samples (n = 30), and environmental swab samples (n = 201) from 17 norovirus outbreaks for crAssphage by real-time PCR. In addition, we tested stool samples from healthy persons (n = 173), respiratory samples (n = 113), and animal fecal specimens (n = 68) and further sequenced positive samples. Overall, we detected crAssphage in 71.4% of outbreak stool samples, 48%-68.5% of stool samples from healthy persons, 56.2% of environmental swabs, and 60% of hand rinse samples, but not in human respiratory samples or animal fecal samples. CrAssphage sequences could be grouped into 2 major genetic clusters. Our data suggest that crAssphage could be used to detect human fecal contamination on environmental surfaces and hands.


Assuntos
Bacteriófagos , Infecções por Caliciviridae , Norovirus , Animais , Infecções por Caliciviridae/epidemiologia , Surtos de Doenças , Fezes , Humanos , Reação em Cadeia da Polimerase em Tempo Real
11.
J Anim Sci Technol ; 62(1): 64-73, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32082600

RESUMO

Producing animal products from farm to table emits massive amounts of greenhouse gases (GHGs). Modified meal plans, mainly including vegetables and grains, have been recommended to reduce GHG emissions. However, these meal plans have not been developed with regard to the micronutrient content, but rather with regard to the energy requirements of grains and vegetables, which could result in a nutritional imbalance. For this reason, we investigated a common Korean suggested meal plan (SMP) from the National Institute of Agricultural Sciences, in which nutritional conditions were considered, and evaluated its GHG emissions using the Life Cycle Assessment Inventory Database and nutritional values. The SMP, which included meat, was based on the Korean Nutrition Society for adult men age 19 to 29, and was changed to a vegan meal plan (VMP). Animal-based protein sources were substituted for meat alternatives, such as beans and tofu, for which carbon footprint data was available. To compare the nutritional differences, the 9th Korean Food Composition Tables I and II were consulted. To calculate GHG emissions, the carbon footprint data of the food was converted to a CO2 equivalent (CO2e) using a procedure from the Foundation of Agriculture Technology Commercialization and Transfer. It was found that GHG emissions per calorie were 18% lower for the VMP when compared to the SMP. However, if GHG emissions per total amino acids were evaluated, the VMP GHG emissions per total amino acids were 0.12 g CO2e/mg, while the corresponding value for the SMP was 0.06 g CO2e/mg. The Korean daily meat intake reported by the Korea Agricultural Statistics Service was 37.1% lower than in the SMP, but when converted to a protein intake the figure was 17.0% lower. It was found that each SMP resulted in more GHG emissions than the VMP, but when considered as GHG emissions per total amino acids, the opposite pattern was apparent. There is a need to conduct more detailed studies of the variation in GHG emissions with different meal plans, using the daily meat intake per person.

12.
JBJS Case Connect ; 9(4): e0512, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31834019

RESUMO

CASE: A 10-year-old boy presented with chronic ulnohumeral subluxation 6 months after an open reduction of a Milch type II lateral condyle fracture subluxation performed at another hospital. The patient had persistent elbow pain and limited range of motion (ROM) between 20° and 50°. After the open reduction for chronic ulnohumeral subluxation and corrective osteotomy for articular surface reconstruction, he had an uneventful recovery with improved ROM of the affected elbow and no pain. CONCLUSIONS: Intra-articular corrective osteotomy for articular surface reconstruction may be feasible to improve mobility and relieve pain in pediatric patients with lateral condylar malunion and elbow subluxation.


Assuntos
Articulação do Cotovelo/cirurgia , Luxações Articulares/diagnóstico por imagem , Osteotomia/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Criança , Articulação do Cotovelo/diagnóstico por imagem , Humanos , Fraturas do Úmero/cirurgia , Luxações Articulares/cirurgia , Masculino , Redução Aberta , Complicações Pós-Operatórias/cirurgia , Tomografia Computadorizada por Raios X
13.
Arch Orthop Trauma Surg ; 139(1): 141-145, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30470906

RESUMO

PURPOSE: An articular depressed fragment at the base of the middle phalanx can be an obstacle to congruent reduction and stable fixation. This study assessed the outcomes of a transosseous reduction technique combined with locking plate fixation for the treatment of articular depressed middle phalangeal base fracture. METHODS: Between 2015 and 2017, seven patients (eight fingers) with intraarticular comminuted middle phalangeal base fracture were included in this study. Mean follow-up was 19 months (range 12-30 months). All patients showed depression of the articular fragment on sagittal computed tomography (CT) scan and were treated with a transosseous reduction technique and dorsal locking plate fixation. Radiographic evaluation was performed to ensure restoration of a concentric articular surface postoperatively. Total active range of motion (TAM) of the finger, grip strength, and the quick Disabilities of the Arm, Shoulder and Hand (quick DASH) score were evaluated at the last follow-up. Complications were also assessed. RESULTS: All fractures obtained bony union with a concentric joint. There was no significant loss of reduction during the follow-up period. The mean active proximal interphalangeal (PIP) joint and distal interphalangeal joint motion arcs at follow-up were 89° and 61°, respectively. Mean TAM of the affected finger and mean grip strength were 94% (range 80-100%) and 94% (range 86-100%) of the contralateral side, respectively. Mean quick DASH score was 2.3 (range 0-9.1). All patients returned to work. No surgery-related complications occurred. CONCLUSIONS: This technique provides satisfactory restoration of articular congruence and enables the early joint mobilization of articular depression-type fractures of the base of the middle phalanx. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, level IV.


Assuntos
Placas Ósseas , Traumatismos dos Dedos/cirurgia , Fixação Interna de Fraturas , Fraturas Cominutivas/cirurgia , Estudos de Coortes , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos
14.
Infect Control Hosp Epidemiol ; 39(2): 219-221, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29331156

RESUMO

We examined norovirus contamination on hands of ill patients during 12 norovirus outbreaks in 12 long-term care facilities (LTCFs). The higher frequency and norovirus titers on hands of residents compared to hands of heathcare workers highlights the importance of adhering to appropriate hand hygiene practices during norovirus outbreaks in LTCFs. Infect Control Hosp Epidemiol 2018;39:219-221.


Assuntos
Infecções por Caliciviridae/transmissão , Infecção Hospitalar/transmissão , Infecção Hospitalar/virologia , Mãos/virologia , Norovirus/isolamento & purificação , Surtos de Doenças , Fezes/virologia , Higiene das Mãos , Humanos , Assistência de Longa Duração , Oregon , Reação em Cadeia da Polimerase , Carga Viral
15.
Genome Announc ; 5(11)2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-28302791

RESUMO

The complete coding sequences of three melon necrotic spot viruses (MNSVs) were obtained from viral metagenomics of stool samples from patients with acute gastroenteritis. These genomes were most similar to Spanish strains sequenced in 2003 and a novel MNSV watermelon strain in 2014.

16.
J Vis Exp ; (120)2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28287539

RESUMO

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the person-to-person route or indirectly through environmental surfaces or food, contaminated fomites and inanimate surfaces are important vehicles for the spread of the virus during norovirus outbreaks. We developed and evaluated a protocol using macrofoam swabs for the detection and typing of human noroviruses from hard surfaces. Compared with fiber-tipped swabs or antistatic wipes, macrofoam swabs allow virus recovery (range 1.2-33.6%) from toilet seat surfaces of up to 700 cm2. The protocol includes steps for the extraction of the virus from the swabs and further concentration of the viral RNA using spin columns. In total, 127 (58.5%) of 217 swab samples that had been collected from surfaces in cruise ships and long-term care facilities where norovirus gastroenteritis had been reported tested positive for GII norovirus by RT-qPCR. Of these 29 (22.8%) could be successfully genotyped. In conclusion, detection of norovirus on environmental surfaces using the protocol we developed may assist in determining the level of environmental contamination during outbreaks as well as detection of virus when clinical samples are not available; it may also facilitate monitoring of effectiveness of remediation strategies.


Assuntos
Infecções por Caliciviridae/diagnóstico , Gastroenterite/diagnóstico , Mucosa Intestinal/virologia , Norovirus/genética , RNA Viral/análise , Manejo de Espécimes/métodos , Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Genótipo , Humanos , Mucosa Intestinal/patologia , Norovirus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real
17.
PLoS One ; 11(6): e0157787, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27337036

RESUMO

Alcohol-based hand sanitizers are widely used to disinfect hands to prevent the spread of pathogens including noroviruses. Alcohols inactivate norovirus by destruction of the viral capsid, resulting in the leakage of viral RNA (virolysis). Since conflicting results have been reported on the susceptibility of human noroviruses against alcohols, we exposed a panel of 30 human norovirus strains (14 GI and 16 GII strains) to different concentrations (50%, 70%, 90%) of ethanol and isopropanol and tested the viral RNA titer by RT-qPCR. Viral RNA titers of 10 (71.4%), 14 (100%), 3 (21.4%) and 7 (50%) of the 14 GI strains were reduced by > 1 log10 RNA copies/ml after exposure to 70% and 90% ethanol, and 70% and 90% isopropanol, respectively. RNA titers of 6 of the 7 non-GII 4 strains remained unaffected after alcohol exposure. Compared to GII strains, GI strains were more susceptible to ethanol than to isopropanol. At 90%, both alcohols reduced RNA titers of 8 of the 9 GII.4 strains by ≥ 1 log10 RNA copies/ml. After exposure to 70% ethanol, RNA titers of GII.4 Den Haag and Sydney strains decreased by ≥ 1.9 log10, whereas RNA reductions for GII.4 New Orleans strains were < 0.5 log10. To explain these differences, we sequenced the complete capsid gene of the 9 GII.4 strains and identified 17 amino acid substitutions in the P2 region among the 3 GII.4 variant viruses. When comparing with an additional set of 200 GII.4 VP1 sequences, only S310 and P396 were present in all GII.4 New Orleans viruses but not in the ethanol-sensitive GII.4 Sydney and GII.4 Den Haag viruses Our data demonstrate that alcohol susceptibility patterns between different norovirus genotypes vary widely and that virolysis data for a single strain or genotype are not representative for all noroviruses.


Assuntos
Álcoois/administração & dosagem , Higienizadores de Mão/administração & dosagem , Norovirus/efeitos dos fármacos , 2-Propanol/administração & dosagem , Sequência de Aminoácidos , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Norovirus/classificação , Norovirus/genética , Fases de Leitura Aberta , Conformação Proteica , Domínios Proteicos , RNA Viral , Análise de Sequência de DNA
18.
Appl Environ Microbiol ; 81(17): 5987-92, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26116675

RESUMO

Inanimate surfaces are regarded as key vehicles for the spread of human norovirus during outbreaks. ISO method 15216 involves the use of cotton swabs for environmental sampling from food surfaces and fomites for the detection of norovirus genogroup I (GI) and GII. We evaluated the effects of the virus drying time (1, 8, 24, or 48 h), swab material (cotton, polyester, rayon, macrofoam, or an antistatic wipe), surface (stainless steel or a toilet seat), and area of the swabbed surface (25.8 cm(2) to 645.0 cm(2)) on the recovery of human norovirus. Macrofoam swabs produced the highest rate of recovery of norovirus from surfaces as large as 645 cm(2). The rates of recovery ranged from 2.2 to 36.0% for virus seeded on stainless-steel coupons (645.0 cm(2)) to 1.2 to 33.6% for toilet seat surfaces (700 cm(2)), with detection limits of 3.5 log10 and 4.0 log10 RNA copies. We used macrofoam swabs to collect environmental samples from several case cabins and common areas of a cruise ship where passengers had reported viral gastroenteritis symptoms. Seventeen (18.5%) of 92 samples tested positive for norovirus GII, and 4 samples could be sequenced and had identical GII.1 sequences. The viral loads of the swab samples from the cabins of the sick passengers ranged from 80 to 31,217 RNA copies, compared with 16 to 113 RNA copies for swab samples from public spaces. In conclusion, our swab protocol for norovirus may be a useful tool for outbreak investigations when no clinical samples are available to confirm the etiology.


Assuntos
Fômites/virologia , Norovirus/isolamento & purificação , Virologia/métodos , Infecções por Caliciviridae/virologia , Contaminação de Equipamentos , Humanos , Norovirus/classificação , Norovirus/genética , RNA Viral/genética , Aço Inoxidável/análise , Virologia/instrumentação
19.
Gut Microbes ; 6(2): 93-100, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25901890

RESUMO

Previous studies have shown bismuth subsalicylate (BSS) has antimicrobial properties, but few studies have addressed the mechanism of action. Furthermore, following BSS ingestion other bismuth salts form throughout the gastrointestinal tract including bismuth oxychloride (BiOCl) that also act upon enteric pathogens. To further understand the antimicrobial activity of bismuth in infectious diarrhea, the antimicrobial effect of BSS and BiOCl on Clostridium difficile, Salmonella, Shigella, Shiga toxin-producing Escherichia coli strains and norovirus (NoV) were measured. Bacterial enteric pathogens in pure culture or in human fecal material were exposed to 35mg/ml BSS or BiOCl with or without a vehicle suspension. BSS and BiOCl treated samples were quantified and visualized by transmission electron microscopy. To measure the effect on NoV, reduction of infectious murine NoV (MNV), a surrogate for human NoV, and Norwalk virus RNA levels were measured by viral plaque assay and RT-qPCR, respectively. BSS and BiOCl reduced bacterial growth by 3-9 logs in all strains with majority resulting in populations of <10 cfu/ml within 24 h. Similar results were found when fecal material was included. Microscopy images detected bismuth on bacterial membranes and within the bacterial organisms at 30 min post-treatment. At 8.8mg/ml BSS and BiOCl reduced infectivity of MNV significantly by 2.7 and 2.0 log after 24 h of exposure. In addition, both BSS and BiOCl slightly reduced the level of Norwalk replicon-bearing cells suggesting that bismuth may inhibit NoV in vivo. Collectively, our results confirm and build on existing data that BSS has antimicrobial properties against a wide-range of diarrhea-causing pathogens.


Assuntos
Anti-Infecciosos/farmacologia , Bismuto/farmacologia , Clostridioides difficile/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Norovirus/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Salicilatos/farmacologia , Animais , Carga Bacteriana , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral , Ensaio de Placa Viral
20.
J Photochem Photobiol B ; 140: 315-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25222145

RESUMO

We evaluated the virucidal efficacy of light-activated fluorinated TiO2 surface coatings on human norovirus and several surrogates (bacteriophage MS2, feline calcivirus (FCV), and murine norovirus (MNV)). Inactivation of viruses on surfaces exposed to a common fluorescent lamp was monitored and the effects of UVA intensity, temperature, and fluoride content were assessed. Destruction of RNA and capsid oxidation were evaluated for human norovirus inocula on the F-TiO2 surfaces, while contact with the F-TiO2 surface and exposure to residual UVA radiation of 10 µW cm(-2) for 60 min resulted in infectivity reductions for the norovirus surrogates of 2-3 log10. Infectivity reductions on pristine TiO2 surfaces in identical conditions were over 2 orders of magnitude lower. Under realistic room lighting conditions, MS2 infectivity declined below the lower detection limit after 12h. Reductions in RNA were generally low, with the exception of GII.4, while capsid protein oxidation likely played a larger role in infectivity loss. Inactivation of norovirus surrogates occurred significantly faster on F-TiO2 compared to pristine TiO2 surfaces. The material demonstrated antiviral action against human norovirus surrogates and was shown to effectively inhibit MS2 when exposed to residual UVA present in fluorescent room lighting conditions in a laboratory setting.


Assuntos
Halogenação , Luz , Norovirus/efeitos dos fármacos , Norovirus/efeitos da radiação , Titânio/química , Titânio/farmacologia , Inativação de Vírus/efeitos dos fármacos , Inativação de Vírus/efeitos da radiação , Animais , Antivirais/química , Antivirais/farmacologia , Gatos , Humanos , Cinética , Camundongos , Norovirus/fisiologia , Propriedades de Superfície
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