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Hepatitis viruses and emerging viruses. FOODBORNE PATHOGENS 2009. [PMCID: PMC7152215 DOI: 10.1533/9781845696337.3.891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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52
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Patnayak DP, Prasad AM, Malik YS, Ramakrishnan MA, Goyal SM. Efficacy of disinfectants and hand sanitizers against avian respiratory viruses. Avian Dis 2008; 52:199-202. [PMID: 18646446 DOI: 10.1637/8097-082807-reg.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Disinfectants play a major role in the control of animal diseases by decontaminating the farm environment. We evaluated the virucidal efficacy of nine commonly used disinfectants on a nonporous surface contaminated experimentally with avian metapneumovirus (aMPV), avian influenza virus, or Newcastle disease virus (NDV). Phenolic compounds and glutaraldehyde were found to be the most effective against all three viruses. Quaternary ammonium compounds were effective against aMPV but not against the other two viruses. In addition, efficacy of commercially available hand sanitizers was evaluated on human fingers contaminated with aMPV and NDV. All three hand sanitizers tested were found to be effective against both viruses within 1 min of application on fingers.
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Affiliation(s)
- Devi P Patnayak
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota. 1333 Gortner Avenue, St. Paul, MN 55108, USA.
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53
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Jacobs JA, Van Ranst M. Biometric fingerprinting for visa application: device and procedure are risk factors for infection transmission. J Travel Med 2008; 15:335-43. [PMID: 19006507 PMCID: PMC7109948 DOI: 10.1111/j.1708-8305.2008.00232.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Biometric fingerprint identity verification is currently introduced in visa application and entry screening at border control. The system implies physical contact between the skin and the surface of the fingerprint-capturing and reading devices. AIM To assess the risk of infection transmission through fingerprinting. METHODS The medical literature was reviewed for the potential of microorganisms to be carried on the skin of hands in the community, to be transferred from hands to inanimate surfaces, to survive on surfaces, and to be transferred in doses exceeding the infectious dose. The fingerprinting procedures as currently applied were reviewed. RESULTS Factors that favor transfer of microorganisms are large skin-surface contact between flat fingers (2 x 20 cm(2)) and fingerprint-capturing device, nonporous contact surface, large overlap of contact surface and short turnaround time between successive applicants, high contact pressure, and difficulties to disinfect devices. Transmission risk exists for enteric viruses (rotavirus, norovirus, and hepatitis A virus), respiratory viruses (respiratory syncytial virus, rhinovirus, influenza virus, etc.), and enteropathogenic bacteria with low infectious doses (Shigella dysenteriae, Enterohemorrhagic Escherichia coli, etc.). Using Monte Carlo risk analysis on US data, transmission of human rotavirus is estimated at 191 [95% credible intervals (CI) 0-289] per million fingerprint-capturing procedures. Application of 70% isopropyl hand rub and 85% ethanol hand gel reduces the risk to 77 (95% CI 0-118) and 0.3 (95% CI 0-0.3) transmissions per million procedures, respectively. CONCLUSIONS The fingerprinting procedure as currently used is associated with a risk of infection transmission. Simple hygienic measures can considerably reduce this transmission risk.
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Affiliation(s)
- Jan A Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine, Central Laboratory of Clinical Biology, Antwerp, Belgium.
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Bacteriophage P22 and Staphylococcus aureus attenuation on nonporous fomites as determined by plate assay and quantitative PCR. Appl Environ Microbiol 2008; 74:5838-40. [PMID: 18621868 DOI: 10.1128/aem.00352-08] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Decay rates of bacteriophage P22 and Staphylococcus aureus on six types of common household inanimate surfaces were evaluated based on cultivation and quantitative PCR. A much higher level of inactivation was observed using the plate assay, suggesting that detection of the pathogen genome in samples from fomites does not necessarily imply a health risk to humans.
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55
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Boone SA, Gerba CP. Significance of fomites in the spread of respiratory and enteric viral disease. Appl Environ Microbiol 2007; 73:1687-96. [PMID: 17220247 PMCID: PMC1828811 DOI: 10.1128/aem.02051-06] [Citation(s) in RCA: 400] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Stephanie A Boone
- University of Arizona, 1117 East Lowell Street Building 90, Room 415, Tucson, AZ 85721, USA.
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56
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Tiwari A, Patnayak DP, Chander Y, Parsad M, Goyal SM. Survival of two avian respiratory viruses on porous and nonporous surfaces. Avian Dis 2006; 50:284-7. [PMID: 16863083 DOI: 10.1637/7453-101205r.1] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The transmission of pathogens from infected to susceptible hosts may occur through contaminated fomites and inanimate objects. This type of transmission depends on the ability of the pathogens to survive in the environment. In this report, we describe the survivability of two avian respiratory viruses, e.g., avian metapneumovirus and avian influenza virus on 12 different porous and nonporous surfaces. The viruses survived on some of the surfaces for up to 6 days postcontamination but not after 9 days. Both viruses survived longer on nonporous surfaces than on porous ones. One of the reasons for poor survival on porous surfaces could be inefficient elution of virus from these surfaces. These results should be helpful in determining how long the premises should be left vacant after an outbreak of these viruses has occurred in poultry houses.
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Affiliation(s)
- A Tiwari
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA
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57
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Kramer A, Schwebke I, Kampf G. How long do nosocomial pathogens persist on inanimate surfaces? A systematic review. BMC Infect Dis 2006; 6:130. [PMID: 16914034 PMCID: PMC1564025 DOI: 10.1186/1471-2334-6-130] [Citation(s) in RCA: 1383] [Impact Index Per Article: 76.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Accepted: 08/16/2006] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Inanimate surfaces have often been described as the source for outbreaks of nosocomial infections. The aim of this review is to summarize data on the persistence of different nosocomial pathogens on inanimate surfaces. METHODS The literature was systematically reviewed in MedLine without language restrictions. In addition, cited articles in a report were assessed and standard textbooks on the topic were reviewed. All reports with experimental evidence on the duration of persistence of a nosocomial pathogen on any type of surface were included. RESULTS Most gram-positive bacteria, such as Enterococcus spp. (including VRE), Staphylococcus aureus (including MRSA), or Streptococcus pyogenes, survive for months on dry surfaces. Many gram-negative species, such as Acinetobacter spp., Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, Serratia marcescens, or Shigella spp., can also survive for months. A few others, such as Bordetella pertussis, Haemophilus influenzae, Proteus vulgaris, or Vibrio cholerae, however, persist only for days. Mycobacteria, including Mycobacterium tuberculosis, and spore-forming bacteria, including Clostridium difficile, can also survive for months on surfaces. Candida albicans as the most important nosocomial fungal pathogen can survive up to 4 months on surfaces. Persistence of other yeasts, such as Torulopsis glabrata, was described to be similar (5 months) or shorter (Candida parapsilosis, 14 days). Most viruses from the respiratory tract, such as corona, coxsackie, influenza, SARS or rhino virus, can persist on surfaces for a few days. Viruses from the gastrointestinal tract, such as astrovirus, HAV, polio- or rota virus, persist for approximately 2 months. Blood-borne viruses, such as HBV or HIV, can persist for more than one week. Herpes viruses, such as CMV or HSV type 1 and 2, have been shown to persist from only a few hours up to 7 days. CONCLUSION The most common nosocomial pathogens may well survive or persist on surfaces for months and can thereby be a continuous source of transmission if no regular preventive surface disinfection is performed.
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Affiliation(s)
- Axel Kramer
- Institut für Hygiene und Umweltmedizin, Ernst-Moritz-Arndt Universität, Greifswald, Germany
| | | | - Günter Kampf
- Institut für Hygiene und Umweltmedizin, Ernst-Moritz-Arndt Universität, Greifswald, Germany
- Bode Chemie GmbH & Co. KG, Scientific Affairs, Hamburg, Germany
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Mocé-Llivina L, Papageorgiou GT, Jofre J. A membrane-based quantitative carrier test to assess the virucidal activity of disinfectants and persistence of viruses on porous fomites. J Virol Methods 2006; 135:49-55. [PMID: 16563525 DOI: 10.1016/j.jviromet.2006.01.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2005] [Revised: 01/29/2006] [Accepted: 01/31/2006] [Indexed: 11/30/2022]
Abstract
A membrane-based quantitative carrier test method to assess the virucidal activity of disinfectants and the persistence of viruses on fomites under different environmental conditions is described. The method is based on the inactivation of the virus adsorbed to cellulose ester membranes followed by the direct enumeration of the viruses surviving the treatment without the need of an elution step. The method was suitable for four different human enteroviruses tested. Experiments comparing the infectivity loss of human enteroviruses in suspension or adsorbed to the filters after treatment with chlorine and glutaraldehyde showed that the human enteroviruses tested suffered significantly greater log10 reductions when suspended than when adsorbed. Significant differences in the effect of the disinfectants on the various human enteroviruses tested were also observed. Moreover, the procedure allowed determining the inactivation of viruses on fomites under different environmental conditions. Low temperatures and high relative humidities favored the survival of human enteroviruses. Also, viruses adsorbed to the membranes retained their infectivity frozen at -70 degrees C for more than 1 year, thus providing the possibility of preparing very simple reference materials for testing virucidal activities of antiseptics and disinfectants.
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Affiliation(s)
- Laura Mocé-Llivina
- Department of Microbiology, School of Biology, University of Barcelona, Avda. Diagonal 645, E-08028 Barcelona, Spain.
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Pazdiora P, Jelínková H, Svecová M, Táborská J. First experience with diagnosing astroviral infections in children hospitalized in Pilsen (Czechia). Folia Microbiol (Praha) 2006; 51:129-32. [PMID: 16821722 DOI: 10.1007/bf02932167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Between the years 2000-2002 astroviral infection was confirmed in 0.8 % of 2606 children admitted for a diarrheal disease to the University Hospital in Pilsen (Czechia). Astrovirus infections most frequently occurred in the age group between 49-60 months, and 77.3 % of the infections occurred in winter. When the incidence was calculated for these most susceptible age groups, the positive rates were 2.4 % (between 49-60 months) and 1.2 % (between 7-12 months) respectively. On average the hospitalization lasted for 5 d, the diarrhea 3.7 d, vomiting 1.1 d, and 40.9 % of infected children had a raised temperature. In 7 out of 872 stool samples (0.8 %), astrovirus antigen has appeared in the course of the monitored period, i.e. nosocomial astrovirus infection was recorded. In view of the rarity of detecting astroviral infections it is probably not effective to include the diagnosis of these infections in the routine panel when examining the children admitted for gastrointestinal infections. The diagnosis of these infections should, however, be performed within the framework of epidemic incidence and in nosocomial infections.
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Affiliation(s)
- P Pazdiora
- Institute of Epidemiology, Medical Faculty, Charles University, 305 99 Pilsen, Czechia.
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60
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Hegedüs M, Kovács G, Módos K, Rontó G, Lammer H, Panitz C, Fekete A. Exposure of phage T7 to simulated space environment: The effect of vacuum and UV-C radiation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2006; 82:94-104. [PMID: 16271480 DOI: 10.1016/j.jphotobiol.2005.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Revised: 08/09/2005] [Accepted: 09/08/2005] [Indexed: 11/15/2022]
Abstract
The experiment "Phage and Uracil Response" (PUR) will be accommodated in the EXPOSE facility of the International Space Station (ISS). Its objective is to examine and quantify the effect of specific space conditions on bacteriophage T7 and isolated T7 DNA thin films. In order to define the environmental and technical requirements of the EXPOSE, the samples were subjected to the Experiment Verification Test (EVT). During EVT the samples were exposed to selected space conditions: high vacuum (10(-4) to 10(-6) Pa) and UV-C radiation (254 nm) alone and in combination. Characteristic changes in the absorption spectrum, in the electrophoretic pattern of DNA/phage and the decrease of the amount of PCR products have been detected indicating the damage of isolated and intraphage T7 DNA. Intraphage DNA is more sensitive to simulated space parameters than isolated T7 DNA in thin layers as well. We obtained substantial evidence that DNA lesions accumulate throughout exposure, and the amount of damage depends on the thickness of the layers. According to our preliminary results, the damages by exposure to conditions of dehydration and UV irradiation are larger than the sum of vacuum alone, or radiation alone case, suggesting a synergistic action of space vacuum and UV radiation with DNA being the critical target.
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Affiliation(s)
- Márton Hegedüs
- Institute of Biophysics and Radiation Biology, Semmelweis University, Puskin u. 9, H-1088 Budapest, Hungary
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Reynolds KA, Watt PM, Boone SA, Gerba CP. Occurrence of bacteria and biochemical markers on public surfaces. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2005; 15:225-34. [PMID: 16134485 DOI: 10.1080/09603120500115298] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
From 1999-2003, the hygiene of 1061 environmental surfaces from shopping, daycare, and office environments, personal items, and miscellaneous activities (i.e., gymnasiums, airports, movie theaters, restaurants, etc.), in four US cities, was monitored. Samples were analyzed for fecal and total coliform bacteria, protein, and biochemical markers. Biochemical markers, i.e., hemoglobin (blood marker), amylase (mucus, saliva, sweat, and urine marker), and urea (urine and sweat marker) were detected on 3% (26/801); 15% (120/801), and 6% (48/801) of the surfaces, respectively. Protein (general hygiene marker) levels > or = 200 microg/10 cm2 were present on 26% (200/801) of the surfaces tested. Surfaces from children's playground equipment and daycare centers were the most frequently contaminated (biochemical markers on 36%; 15/42 and 46%; 25/54, respectively). Surfaces from the shopping, miscellaneous activities, and office environments were positive for biochemical markers with a frequency of 21% (69/333), 21% (66/308), and 11% (12/105), respectively). Sixty samples were analyzed for biochemical markers and bacteria. Total and fecal coliforms were detected on 20% (12/60) and 7% (4/ 60) of the surfaces, respectively. Half and one-third of the sites positive for biochemical markers were also positive for total and fecal coliforms, respectively. Artificial contamination of public surfaces with an invisible fluorescent tracer showed that contamination from outside surfaces was transferred to 86% (30/ 35) of exposed individual's hands and 82% (29/35) tracked the tracer to their home or personal belongings hours later. Results provide information on the relative hygiene of commonly encountered public surfaces and aid in the identification of priority environments where contaminant occurrence and risk of exposure may be greatest. Children's playground equipment is identified as a priority surface for additional research on the occurrence of and potential exposure to infectious disease causing agents.
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Affiliation(s)
- Kelly A Reynolds
- The University of Arizona, Department of Soil, Water and Environmental Science, Environmental Research Laboratory, 2601 E. Airport Drive, Tucson, AZ 85706, USA.
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63
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Guix S, Caballero S, Bosch A, Pintó RM. Human astrovirus C-terminal nsP1a protein is involved in RNA replication. Virology 2005; 333:124-31. [PMID: 15708598 DOI: 10.1016/j.virol.2004.12.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2004] [Revised: 10/07/2004] [Accepted: 12/20/2004] [Indexed: 11/23/2022]
Abstract
Human astrovirus nonstructural C-terminal nsP1a protein, which contains a hypervariable region (HVR) and colocalizes with the endoplasmic reticulum and viral RNA, has been suggested to be involved in the RNA replication process. Four viruses differing only in their C-terminal nsP1a protein, corresponding to HVR-derived genotypes IV, V, VI, and XII, were all able to replicate in CaCo-2 cells but displayed differences in their RNA replication and growth properties. Two overall patterns of replication were observed: types IV and V on one side, and types VI and XII on the other. The main detected differences were on the levels of antigenomic and subgenomic RNAs, being the latter significantly higher in types IV and V. Accordingly, quantification of viral RNA load in feces from children with gastroenteritis showed that HVR-derived genotypes IV and V occur in significantly higher numbers. In consequence, it may be concluded that the variability of the C-terminal nsP1a gene affects the virus replication phenotype.
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Affiliation(s)
- Susana Guix
- Department of Microbiology, Enteric Virus Laboratory, University of Barcelona, Diagonal 645, 08028 Barcelona, Spain
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Rzezutka A, Cook N. Survival of human enteric viruses in the environment and food. FEMS Microbiol Rev 2004; 28:441-53. [PMID: 15374660 DOI: 10.1016/j.femsre.2004.02.001] [Citation(s) in RCA: 197] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2003] [Revised: 12/09/2003] [Accepted: 02/15/2004] [Indexed: 10/26/2022] Open
Abstract
Human enteric pathogenic viruses can enter the environment through discharge of waste materials from infected persons, and be transmitted back to susceptible persons to continue the cycle of disease. Contamination of food with viruses may also promote disease outbreaks. A number of studies have investigated the survival characteristics of several enteric viruses in various environments and foodstuffs, to help explain the transmissibility of these pathogens. This review deals with published work on enteric virus survival on fomites, and in waters, soil, and foods; the results of these studies have illustrated the robust survival of viruses in these environments. Much information is lacking, however, especially for foodstuffs and soils, and no detailed information is available concerning the survival of noroviruses, the most significant foodborne type.
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Affiliation(s)
- Artur Rzezutka
- DEFRA Central Science Laboratory, Sand Hutton, York YO41 1LZ, UK
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65
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Kampf G, Kramer A. Epidemiologic background of hand hygiene and evaluation of the most important agents for scrubs and rubs. Clin Microbiol Rev 2004; 17:863-93, table of contents. [PMID: 15489352 PMCID: PMC523567 DOI: 10.1128/cmr.17.4.863-893.2004] [Citation(s) in RCA: 416] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The etiology of nosocomial infections, the frequency of contaminated hands with the different nosocomial pathogens, and the role of health care workers' hands during outbreaks suggest that a hand hygiene preparation should at least have activity against bacteria, yeasts, and coated viruses. The importance of efficacy in choosing the right hand hygiene product is reflected in the new Centers for Disease Control and Prevention guideline on hand hygiene (J. M. Boyce and D. Pittet, Morb. Mortal. Wkly. Rep. 51:1-45, 2002). The best antimicrobial efficacy can be achieved with ethanol (60 to 85%), isopropanol (60 to 80%), and n-propanol (60 to 80%). The activity is broad and immediate. Ethanol at high concentrations (e.g., 95%) is the most effective treatment against naked viruses, whereas n-propanol seems to be more effective against the resident bacterial flora. The combination of alcohols may have a synergistic effect. The antimicrobial efficacy of chlorhexidine (2 to 4%) and triclosan (1 to 2%) is both lower and slower. Additionally, both agents have a risk of bacterial resistance, which is higher for chlorhexidine than triclosan. Their activity is often supported by the mechanical removal of pathogens during hand washing. Taking the antimicrobial efficacy and the mechanical removal together, they are still less effective than the alcohols. Plain soap and water has the lowest efficacy of all. In the new Centers for Disease Control and Prevention guideline, promotion of alcohol-based hand rubs containing various emollients instead of irritating soaps and detergents is one strategy to reduce skin damage, dryness, and irritation. Irritant contact dermatitis is highest with preparations containing 4% chlorhexidine gluconate, less frequent with nonantimicrobial soaps and preparations containing lower concentrations of chlorhexidine gluconate, and lowest with well-formulated alcohol-based hand rubs containing emollients and other skin conditioners. Too few published data from comparative trials are available to reliably rank triclosan. Personnel should be reminded that it is neither necessary nor recommended to routinely wash hands after each application of an alcohol-based hand rub. Long-lasting improvement of compliance with hand hygiene protocols can be successful if an effective and accessible alcohol-based hand rub with a proven dermal tolerance and an excellent user acceptability is supplied, accompanied by education of health care workers and promotion of the use of the product.
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Affiliation(s)
- Günter Kampf
- Bode Chemie GmbH & Co., Scientific Affairs, Melanchthonstrasse 27, 22525 Hamburg, Germany.
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Guix S, Bosch A, Ribes E, Dora Martínez L, Pintó RM. Apoptosis in astrovirus-infected CaCo-2 cells. Virology 2004; 319:249-61. [PMID: 14980485 PMCID: PMC7127648 DOI: 10.1016/j.virol.2003.10.036] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2003] [Revised: 10/20/2003] [Accepted: 10/23/2003] [Indexed: 02/08/2023]
Abstract
Cell death processes during human astrovirus replication in CaCo-2 cells and their underlying mechanisms were investigated. Morphological and biochemical alterations typical of apoptosis were analyzed in infected cells using a combination of techniques, including DAPI staining, the sub-G0/G1 technique and the TUNEL assay. The onset of apoptosis was directly proportional to the virus multiplicity of infection. Transient expression experiments showed a direct link between astrovirus ORF1a encoded proteins and apoptosis induction. A computer analysis of the astrovirus genome revealed the presence of a death domain in the nonstructural protein p38 of unknown function, encoded in ORF1a. Apoptosis inhibition experiments suggested the involvement of caspase 8 in the apoptotic response, and led to a reduction in the infectivity of the virus progeny released to the supernatant. We conclude that apoptotic death of host cells seems necessary for efficient human astrovirus replication and particle maturation.
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Affiliation(s)
- Susana Guix
- Enteric Virus Group, Department of Microbiology, University of Barcelona, Spain
| | - Albert Bosch
- Enteric Virus Group, Department of Microbiology, University of Barcelona, Spain
- Corresponding author. Department of Microbiology, School of Biology, University of Barcelona, Avda Diagonal 645, 08028 Barcelona, Spain. Fax: +34-93-4034629.
| | - Enric Ribes
- Enteric Virus Group, Department of Cell Biology, University of Barcelona, Spain
| | - L. Dora Martínez
- Enteric Virus Group, Department of Microbiology, University of Barcelona, Spain
| | - Rosa M. Pintó
- Enteric Virus Group, Department of Microbiology, University of Barcelona, Spain
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67
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Grimm AC, Cashdollar JL, Williams FP, Fout GS. Development of an astrovirus RT–PCR detection assay for use with conventional, real-time, and integrated cell culture/RT–PCR. Can J Microbiol 2004; 50:269-78. [PMID: 15213751 DOI: 10.1139/w04-012] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Astrovirus is a common cause of gastroenteritis in humans that has been determined to be responsible for outbreaks of illness in several countries. Since astrovirus can be waterborne, it is important to be able to identify this virus in environmental water. We have developed and optimized a reverse transcription – polymerase chain reaction (RT–PCR) method that was able to amplify all eight astrovirus serotypes in a single reaction. In addition, a positive control construct was designed so that any inhibitors of this astrovirus assay could be detected. The assay was adapted for use in a real-time PCR assay and the sensitivity of these two methods was compared. The real-time assay was then combined with CaCo2 cell culture to produce an integrated cell culture/RT–PCR (ICC/RT–PCR) assay that was able to detect low levels of astrovirus after an incubation of 7 days or less. Also, the sensitivity of the ICC/RT–PCR assay was compared with RT–PCR alone. The methods were used to detect astrovirus in acute phase illness stool samples as well as in a water sample spiked with astrovirus.Key words: astrovirus, RT–PCR, real-time PCR, ICC/RT–PCR, environmental water.
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Affiliation(s)
- Ann C Grimm
- Biohazard Assessment Research Branch, national Exposure Research laboratory, US Environmental Protection Agency, Cincinnati, OH 45268, USA.
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68
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Ottosson J, Stenström TA. Growth and reduction of microorganisms in sediments collected from a greywater treatment system. Lett Appl Microbiol 2003; 36:168-72. [PMID: 12581377 DOI: 10.1046/j.1472-765x.2003.01286.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To study the effects of competitive microbiota, temperature and nutrient availability on Salmonella, Enterococcus, Campylobacter spores of sulphite reducing anaerobes and bacteriophages MS2 and phiX174 in sediments from a greywater treatment system. METHODS AND RESULTS Standard culture methods were used. Bacteria died off rapidly under normal conditions (20 degrees C, competitive microbiota) but remained stable or grew in the other conditions studied. When the sediments became nutrient depleted after 2 weeks, a log-linear die-off was observed for Salmonella, which was higher at 20 degrees C than at 4 degrees C. Bacteriophage decay was shown to be log-linear from day 0, with T90 values ranging from 9 (phiX174, 20 degrees C) to 55 days (phiX174, 4 degrees C). The MS2 phage had a significantly higher decay rate in tyndallized sediments (T90 = 17 days) than in original sediments (T90 = 47 days) (P < 0.001), with temperature not shown to affect the decay rate. Spores of sulphite-reducing anaerobes were not significantly reduced during the study period (35 days). Campylobacter died-off rapidly or entered a viable but non-culturable state and subsequently results were not provided. CONCLUSIONS Competition was the most important factor to suppress pathogenic bacterial growth in an eutrophic environment. When nutrient depleted conditions prevailed, temperature was more important and log-linear decay of microorganisms could be observed. SIGNIFICANCE AND IMPACT OF THE STUDY These findings suggest that the normally occurring microbiota will suppress pathogenic bacterial growth in nutrient rich sediments. With lower nutrient status, temperature is the more important factor in reducing pathogens.
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Affiliation(s)
- J Ottosson
- Water and Environmental Microbiology, SMI, Swedish Institute for Infectious Disease Control, Solna, Sweden.
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Sattar SA, Springthorpe VS, Tetro J, Vashon R, Keswick B. Hygienic hand antiseptics: should they not have activity and label claims against viruses? Am J Infect Control 2002; 30:355-72. [PMID: 12360145 PMCID: PMC7172183 DOI: 10.1067/mic.2002.124532] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Enteric and respiratory viruses are among the most frequent causes of human infections, and hands play an important role in the spread of these and many other viral diseases. Regular and proper hand hygiene by caregivers and food handlers in particular is essential to decontaminate hands and potentially interrupt such spread. What would be considered a proper decontamination of hands? Handwashing with regular soap and water is often considered sufficient, but what of hygienic handwash and handrub antiseptic products? Are they more effective? The evidence suggests that some clearly are. Activity against bacteria may not reflect the ability of hygienic hand antiseptics to deal with viruses, especially those that are nonenveloped. In spite of the acknowledged importance of hands as vehicles for viruses, there is a lack of suitable regulatory mechanism for handwash or handrub products to make claims of efficacy against viruses. This is in contrast with the ability of general-purpose disinfectants to make antiviral claims, although transmission of viruses from surfaces other than those of reusable medical devices may play only a minor role in virus transmission. This review discusses the (1). recent information on the relative importance of viruses as human pathogens, particularly those causing enteric and respiratory infections; (2). the survival of relevant viruses on human hands in comparison with common gram-negative and gram-positive bacteria; (3). the potential of hands to transfer or receive such contamination on casual contact; (4). role of hands in the spread of viruses; (5). the potential of hygienic measures to eliminate viruses from contaminated hands; (6). relative merits of available protocols to assess the activity of hygienic hand antiseptics against viruses; and (7). factors considered crucial in any tests to assess the activity of hygienic hand antiseptics against viruses. In addition, this review proposes surrogate viruses in such testing and discusses issues for additional consideration by researchers, manufacturers, end-users, and regulators.
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Affiliation(s)
- Syed A Sattar
- Centre for Research on Environmental Microbiology, Faculty of Medicine, University of Ottawa, and the Procter & Gamble Co, Cincinnati and Mason, Ohio, USA
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