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Characteristics of selected active substances used in disinfectants and their virucidal activity against ASFV
2019
Juszkiewicz, Małgorzata | Walczak, Marek | Woźniakowski, Grzegorz
African swine fever (ASF), caused by African swine fever virus (ASFV), is currently one of the most important and serious diseases of pigs, mainly due to the enormous sanitary and socio-economic consequences. It leads to serious economic losses, not only because of the near 100% mortality rate, but also through the prohibitions of pork exports it triggers. Currently neither vaccines nor safe and effective chemotherapeutic agents are available against ASFV. The disease is controlled by culling infected pigs and maintaining high biosecurity standards, which principally relies on disinfection. Some countries have approved and/or authorised a list of biocides effective against this virus. This article is focused on the characteristics of chemical substances present in the most popular disinfectants of potential use against ASFV. Despite some of them being approved and tested, it seems necessary to perform tests directly on ASFV to ensure maximum effectiveness of the disinfectants in preventing the spread of ASF in the future.
اظهر المزيد [+] اقل [-]Comparison of the bacteriostatic effects of quaternary ammonium compounds and their combinations on a dairy farm environment and the microbial contamination of dairy products
2021
Chen, Nannan | Liu, Shanshan | Liu, Yu | Bai, Tongtong | Jia, Lihua | Wang, Li | Yue, Shan | Wu, Chenhua | Huang, Wenjing | Gao, Li | Fu, Jinlei | Liu, Siyu | Zhao, Tong | Li, Juan | Zhang, Yuntao | Zhu, Zhanbo
Disinfection is key for controlling microbial contamination and ensuring the safe production of milk and dairy products. In this study, we developed a new disinfection method using quaternary ammonium surfactant N-dodecyl-2-(pyridin-1-yl) acetamide chloride as the main component to form a bactericidal complex with either chlorhexidine acetate or glutaraldehyde, and we evaluated the bactericidal effects, safety, and clinical application value of the compound disinfectants. An in vivo acute oral toxicity assay in mice showed an LD50 > 5000 mg/kg body weight without abnormality in pathological tissue sections. Comparison with commercially available products also showed that they have outstanding bactericidal effects. Clinical trials proved that the compound disinfectants have excellent bactericidal effects on the air and ground of the dairy farm and on the skin of cattle, especially in a dairy farm environment. Our findings confirm that the new compound disinfectants have excellent bactericidal performance and are safe to use as disinfectants to prevent mastitis and contamination of the cattle farm environment.
اظهر المزيد [+] اقل [-]Investigation of the effects of an ultraviolet germicidal irradiation system on concentrations of aerosolized surrogates for common veterinary pathogens
2020
Pearce-Walker, Jennifer I. | Troup, Daniel J. | Streeter, Rebecca Ives | Ikner, Luisa A. | Rose, Joan B. | Kennedy, Melissa A. | Verhougstraete, Marc P.
OBJECTIVE To determine whether exposure to UV germicidal irradiation (UVGI) reduces concentrations of viable aerosolized microorganisms (attenuated strains of common veterinary pathogens) in a simulated heating, ventilation, and air conditioning (HVAC) system. SAMPLE 42 air samples seeded with bacteriophage MS2 or attenuated strains of Bordetella bronchiseptica, feline calicivirus, feline herpesvirus-1, canine parvovirus, or canine distemper virus (6/microorganism) or with no microorganisms added (6). PROCEDURES A simulated HVAC unit was built that included a nebulizer to aerosolize microorganisms suspended in phosphate-buffered water, a fan to produce airflow, 2 UVGI bulb systems, and an impinger for air sampling. Ten-minute trials (3 with UVGI, 3 without UVGI, and 1 negative control) were conducted for each microorganism. Impingers collected microorganisms into phosphate-buffered water for subsequent quantification with culture-based assays. Results for samples yielding no target microorganisms were recorded as the assay's lower limit of detection. Statistical analysis was not performed. RESULTS The UVGI treatment resulted in subjectively lower concentrations of viable MS2, B bronchiseptica, and canine distemper virus (arithmetic mean ± SD log10 microorganism reduction, 2.57 ± 0.47, ≥ 3.45 ± 0.24, and ≥ 1.50 ± 0.25, respectively) collected from air. Feline herpesvirus-1 was detected in only 1 sample without and no samples with UVGI treatment. Feline calicivirus and canine parvovirus were not detectable in any collected samples. CONCLUSIONS AND CLINICAL RELEVANCE Results for some surrogates of veterinary pathogens suggested a potential benefit to supplementing manual disinfection practices with UVGI-based air cleaning systems in animal care environments. Further research is needed to investigate the utility of UVGI in operating HVAC systems.
اظهر المزيد [+] اقل [-]Bacterial biofilms: their importance in animal health and public health | Les biofilms bactériens : leur importance en santé animale et en santé publique
2014
Tremblay, Yannick D.N. | Hathroubi, Skander | Jacques, Mario
Bacterial biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that is attached to a surface. Biofilms protect and allow bacteria to survive and thrive in hostile environments. Bacteria within biofilms can withstand host immune responses, and are much less susceptible to antibiotics and disinfectants when compared to their planktonic counterparts. The ability to form biofilms is now considered an attribute of many microorganisms. Diseases associated with biofilms require novel methods for their prevention, diagnosis and treatment; this is largely due to the properties of biofilms. Furthermore, the presence of biofilms on surfaces found at farms, slaughterhouses or food processing plants will have an impact on the efficacy of disinfection protocols. Surprisingly, biofilm formation by bacterial pathogens of veterinary or zoonotic importance has received relatively little attention. The objective of this brief Review article is to bring awareness about the importance of biofilms to animal health stakeholders.
اظهر المزيد [+] اقل [-]Effectiveness of a steam cleaning unit for disinfection in a veterinary hospital
2014
Wood, Cheryl L. | Tanner, Benjamin D. | Higgins, Laura A. | Dennis, Jeffrey S. | Luempert, Louis G lll
Objective—To evaluate whether the application of steam to a variety of surface types in a veterinary hospital would effectively reduce the number of bacteria. Sample—5 surface types.Procedures—Steam was applied as a surface treatment for disinfection to 18 test sites of 5 surface types in a veterinary hospital. A pretreatment sample was obtained by collection of a swab specimen from the left side of each defined test surface. Steam disinfection was performed on the right side of each test surface, and a posttreatment sample was then collected in the same manner from the treated (right) side of each test surface. Total bacteria for pretreatment and posttreatment samples were quantified by heterotrophic plate counts and for Staphylococcus aureus, Pseudomonas spp, and total coliforms by counts on selective media. Results—Significant reductions were observed in heterotrophic plate counts after steam application to dog runs and dog kennel floors. A significant reduction in counts of Pseudomonas spp was observed after steam application to tub sinks. Bacterial counts were reduced, but not significantly, on most other test surfaces that had adequate pretreatment counts for quantification. Conclusions and Clinical Relevance—Development of health-care–associated infections is of increasing concern in human and veterinary medicine. The application of steam significantly reduced bacterial numbers on a variety of surfaces within a veterinary facility. Steam disinfection may prove to be an alternative or adjunct to chemical disinfection within veterinary practices.
اظهر المزيد [+] اقل [-]Influence of temperature and organic load on chemical disinfection of Geobacillus steareothermophilus spores, a surrogate for Bacillus anthracis
2013
Guan, Jiewen | Chan, Maria | Brooks, Brian W. | Rohonczy, Liz
This study evaluated the influence of temperature and organic load on the effectiveness of domestic bleach (DB), Surface Decontamination Foam (SDF), and Virkon in inactivating Geobacillus stearothermophilus spores, which are a surrogate for Bacillus anthracis spores. The spores were suspended in light or heavy organic preparations and the suspension was applied to stainless steel carrier disks. The dried spore inoculum was covered with the disinfectants and the disks were then incubated at various temperatures. At −20°C, the 3 disinfectants caused less than a 2.0 log10 reduction of spores in both organic preparations during a 24-h test period. At 4°C, the DB caused a 4.4 log10 reduction of spores in light organic preparations within 2 h, which was about 3 log10 higher than what was achieved with SDF or Virkon. In heavy organic preparations, after 24 h at 4°C the SDF had reduced the spore count by 4.5 log10, which was about 2 log10 higher than for DB or Virkon. In general, the disinfectants were most effective at 23°C but a 24-h contact time was required for SDF and Virkon to reduce spore counts in both organic preparations by at least 5.5 log10. Comparable disinfecting activity with DB only occurred with the light organic load. In summary, at temperatures as low as 4°C, DB was the most effective disinfectant, inactivating spores within 2 h on surfaces with a light organic candload, whereas SDF produced the greatest reduction of spores within 24 h on surfaces with a heavy organic load.
اظهر المزيد [+] اقل [-]Evaluation of Practiced Biosecurity Measures in Selected Broiler Farms across Kabul Province, Afghanistan
2023
Assadullah Samadi | Naqibshah Zadran
Biosecurity is an important tool to exclude potential pathogens from the poultry farms and to maintain the health, welfare and productivity of the stocks. Therefore, a cross-sectional study was designed to evaluate the biosecurity measures practiced in 50 selected broiler farms in four districts of Kabul province of Afghanistan. Data were collected by structured interview using a pre-designed questionnaire. This study revealed that all of the studied farms practiced the biosecurity measures from medium to the high levels, but these levels were not statistically significant based on the study districts and farms size (p>0.05). Disinfection of the farms at the end of each production cycle (100%) along with the disinfection of boots (86%) and vehicle (76%) and routine vaccines administrations (98%) were the most common practiced internal biosecurity measures, while inappropriate farm location, insufficient pest control and improper dead bird disposal were the main non-practiced external biosecurity measures in the surveyed farms. Hence, it is highly recommended to the animal health and production authorities to develop and implement specific biosecurity guidelines to the national level using regional and international manuals.
اظهر المزيد [+] اقل [-]Enhanced inactivation of avian influenza virus at −20°C by disinfectants supplemented with calcium chloride or other antifreeze agents
2015
Guan, Jiewen | Chan, Maria | Brooks, Brian W. | Rohonczy, Elizabeth
Avian influenza outbreaks have occurred during winter months, and effective disinfection of poultry premises at freezing temperatures is needed. The commercial disinfectants Virkon and Accel, supplemented with an antifreeze agent [propylene glycol (PG), methanol (MeOH), or calcium chloride (CaCl2)], were evaluated for their effectiveness in killing avian influenza virus (AIV) at −20°C or 21°C. An AIV suspension was applied to stainless steel disks, air-dried, and covered with a disinfectant or antifreeze agent for 5 to 30 min. Virkon (2%) and Accel (6.25%) with 30% PG, 20% MeOH, or 20% CaCl2 inactivated 6 log10 AIV within 5 min at −20°C and 21°C. At these temperatures PG and MeOH alone did not kill AIV, but the 20% CaCl2 solution alone inactivated 5 log10 AIV within 10 min. The results suggested that CaCl2 is potentially useful to enhance the effectiveness of disinfection of poultry facilities after outbreaks of AIV infection in warm and cold seasons.
اظهر المزيد [+] اقل [-]Inactivation of SARS coronavirus by means of povidone-iodine, physical conditions, and chemical reagents
2004
Kariwa, H. (Hokkaido Univ., Sapporo (Japan)) | Fujii, N. | Takashima, I.
The efficacy of several povidone-iodine (PVP-I) products, a number of other chemical agents, and various physical conditions were evaluated for their ability to inactivate the severe acute respiratory syndrome coronavirus (SARS-CoV). Treatment of SARS-CoV with PVP-I products for 2 min reduced the virus infectivity from 1.17 x 10**6 TCID sub(50)/ml to below the detectable level. The efficacy of 70% ethanol was equivalent to that of PVP-I products. Fixation of SARS-CoV-infected Vero E6 cells with a fixative including formalin, glutaraldehyde, methanol, and acetone for 5 min or longer eliminated all infectivity. Heating the virus at 56 deg C for 5 min dramatically reduced the infectivity of the virus from 2.6 x 10**7 to 40 TCID sub(50)/ml, whereas heating the virus for 60 min or longer eliminated all infectivity. Irradiation with ultraviolet light at 134MicroW/square cm for 15 min reduced the infectivity from 3.8 x 10**7 to 180 TCID sub(50)/ml; however, prolonged irradiation (60 min) failed to eliminate the remaining virus, leaving 18.8 TCID sub(50)/ml. We believe that these findings will be useful for the implementation of infection contiol measures against SARS, and for the establishment of effective guidelines for the prevention of SARS outbreaks.
اظهر المزيد [+] اقل [-]Mixed viral infections in village chickens
2015
Leow, B. L. | Norazura B. | Mohd Jihan R. | Mohd Khairil A. | Basirah M. A. | Ong, G. H. | Faizul Fikri M. Y. | Ramlan M. | Maizatul Z. | Muhammad Redzwan S.
A mixed viral infection of Newcastle Disease (ND), Marek’s Disease (MD) and Avian Leukosis (AL) was reported in village chickens. Analysis of the deduced amino acid sequences of the F protein cleavage site of ND virus showed that the isolate was virulent with sequence KRRKR for the C-terminus of the F2 protein and phenylanine (F) at residue 117, the N-terminus of the F1 protein. Basic Local Alignment Search Tool (BLAST) analysis showed the isolate was ND which was 96% similar identity with Indonesia Sukorejo genotype VII, MD 99% similar identity with China very virulent strain and ALV 100% similar identity with Taiwan ALV strain. Due to the free ranging type of management, causes of the diseases in the poultry were uncertain as many factors can contribute to the disease occurrence. However, good hygiene practices can help to improve the farm’s sanitary. Basic biosecurity system can be applied although the success may be limited. Vaccination is another alternative that can be considered to prevent the diseases with the help from certain parties.
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