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Hu Z, Tian X, Lai R, Ji C, Li X. Airborne transmission of common swine viruses. Porcine Health Manag 2023; 9:50. [PMID: 37908005 PMCID: PMC10619269 DOI: 10.1186/s40813-023-00346-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/25/2023] [Indexed: 11/02/2023] Open
Abstract
The transmission of viral aerosols poses a vulnerable aspect in the biosecurity measures aimed at preventing and controlling swine virus in pig production. Consequently, comprehending and mitigating the spread of aerosols holds paramount significance for the overall well-being of pig populations. This paper offers a comprehensive review of transmission characteristics, influential factors and preventive strategies of common swine viral aerosols. Firstly, certain viruses such as foot-and-mouth disease virus (FMDV), porcine reproductive and respiratory syndrome virus (PRRSV), influenza A viruses (IAV), porcine epidemic diarrhea virus (PEDV) and pseudorabies virus (PRV) have the potential to be transmitted over long distances (exceeding 150 m) through aerosols, thereby posing a substantial risk primarily to inter-farm transmission. Additionally, other viruses like classical swine fever virus (CSFV) and African swine fever virus (ASFV) can be transmitted over short distances (ranging from 0 to 150 m) through aerosols, posing a threat primarily to intra-farm transmission. Secondly, various significant factors, including aerosol particle sizes, viral strains, the host sensitivity to viruses, weather conditions, geographical conditions, as well as environmental conditions, exert a considerable influence on the transmission of viral aerosols. Researches on these factors serve as a foundation for the development of strategies to combat viral aerosol transmission in pig farms. Finally, we propose several preventive and control strategies that can be implemented in pig farms, primarily encompassing the implementation of early warning models, viral aerosol detection, and air pretreatment. This comprehensive review aims to provide a valuable reference for the formulation of efficient measures targeted at mitigating the transmission of viral aerosols among swine populations.
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Affiliation(s)
- Zhiqiang Hu
- Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology, Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd, Xiajin Economic Development Zone, Qingwo Venture Park, Dezhou, 253200, Shandong Province, People's Republic of China
- Shandong New Hope Liuhe Co., Ltd, No. 592-26 Jiushui East Road Laoshan District, Qingdao, 266100, Shandong, People's Republic of China
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd (NHLH Academy of Swine Research), 6596 Dongfanghong East Road, Yuanqiao Town, Dezhou, 253000, Shandong, People's Republic of China
- China Agriculture Research System-Yangling Comprehensive Test Station, Intersection of Changqing Road and Park Road 1, Yangling District, Xianyang, People's Republic of China
| | - Xiaogang Tian
- Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology, Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd, Xiajin Economic Development Zone, Qingwo Venture Park, Dezhou, 253200, Shandong Province, People's Republic of China
- Shandong New Hope Liuhe Co., Ltd, No. 592-26 Jiushui East Road Laoshan District, Qingdao, 266100, Shandong, People's Republic of China
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd (NHLH Academy of Swine Research), 6596 Dongfanghong East Road, Yuanqiao Town, Dezhou, 253000, Shandong, People's Republic of China
| | - Ranran Lai
- Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology, Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd, Xiajin Economic Development Zone, Qingwo Venture Park, Dezhou, 253200, Shandong Province, People's Republic of China
- Shandong New Hope Liuhe Co., Ltd, No. 592-26 Jiushui East Road Laoshan District, Qingdao, 266100, Shandong, People's Republic of China
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd (NHLH Academy of Swine Research), 6596 Dongfanghong East Road, Yuanqiao Town, Dezhou, 253000, Shandong, People's Republic of China
| | - Chongxing Ji
- Key Laboratory of Feed and Livestock and Poultry Products Quality and Safety Control, Ministry of Agriculture and Rural Affairs, New Hope Liuhe Co., Ltd, 316 Jinshi Road, Chengdu, 610100, Sichuan, People's Republic of China
- Shandong New Hope Liuhe Co., Ltd, No. 592-26 Jiushui East Road Laoshan District, Qingdao, 266100, Shandong, People's Republic of China
| | - Xiaowen Li
- Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology, Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd, Xiajin Economic Development Zone, Qingwo Venture Park, Dezhou, 253200, Shandong Province, People's Republic of China.
- Key Laboratory of Feed and Livestock and Poultry Products Quality and Safety Control, Ministry of Agriculture and Rural Affairs, New Hope Liuhe Co., Ltd, 316 Jinshi Road, Chengdu, 610100, Sichuan, People's Republic of China.
- Shandong New Hope Liuhe Co., Ltd, No. 592-26 Jiushui East Road Laoshan District, Qingdao, 266100, Shandong, People's Republic of China.
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd (NHLH Academy of Swine Research), 6596 Dongfanghong East Road, Yuanqiao Town, Dezhou, 253000, Shandong, People's Republic of China.
- China Agriculture Research System-Yangling Comprehensive Test Station, Intersection of Changqing Road and Park Road 1, Yangling District, Xianyang, People's Republic of China.
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Tan L, Zhou Y, Qiu Y, Lei L, Wang C, Zhu P, Duan D, Lei H, Yang L, Wang N, Yang Y, Yao J, Wang W, Wang A. Pseudorabies in pig industry of China: Epidemiology in pigs and practitioner awareness. Front Vet Sci 2022; 9:973450. [PMID: 36213396 PMCID: PMC9536195 DOI: 10.3389/fvets.2022.973450] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Pseudorabies virus (PRV) is widely prevalent in China, which can transmit from pigs to other mammals. Moreover, a PRV variant isolated from an acute human encephalitis case was documented recently. It is imperative to investigate PRV epidemiology in pigs, the knowledge regarding pseudorabies (PR) and self-protection behaviors upon working among relevant practitioners including pig farmers, pig cutters, and pork salesman. In the present study, 18,812 pig serum samples and 1,634 tissue samples were collected from Hunan Province during the period of 2020 to 2021 for detecting the presence of PRV gE-special antibody and nucleic acids, respectively. Meanwhile, we conducted a questionnaire survey about PR among these practitioners in China. The results showed that nearly 9% (1,840/20,192) pigs from 161 collected sites (20.17%, 161/797) were seropositive for PRV-gE antibody. Though only 2.33% tissue samples were positive for PRV nucleic acids, all the representative PRV strains were variant. It was learned that most practitioners were frequently injured when working, the injured sites mainly included hand and foot. Among the three transmission routes of PRV, the aerosol transmission route was often overlooked. Moreover, the workers lacked self-protection awareness and were poor conscious about PRV and its potential threat to humans. All the results demonstrate that PRV remains widely spread in pig populations, while the potential threats of PRV in pig industry receive less attention, suggesting that targeted educational programs to these people should be performed.
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Affiliation(s)
- Lei Tan
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Yujun Zhou
- Hunan Sino-science Gene Technology Co., Ltd, Changsha, China
| | - Yixing Qiu
- TCM and Ethnomedicine Innovation and Development International Laboratory, Academician Atta-ur-Rahman Belt and Road Traditional Medicine Research Center, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, China
| | - Lei Lei
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Cheng Wang
- Xiangxi Prefecture Animal Husbandry and Aquatic Products Affairs Center, Xiangxi, China
| | - Pei Zhu
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
| | - Deyong Duan
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Hongyu Lei
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Lincheng Yang
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Naidong Wang
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Yi Yang
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
| | - Jun Yao
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
- *Correspondence: Jun Yao
| | - Wei Wang
- TCM and Ethnomedicine Innovation and Development International Laboratory, Academician Atta-ur-Rahman Belt and Road Traditional Medicine Research Center, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, China
- Wei Wang
| | - Aibing Wang
- Lab of Animal Disease Prevention and Control and Animal Model, Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, China
- PCB Biotechnology LLC, Rockville, MD, United States
- Aibing Wang
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Van Leuken J, Swart A, Havelaar A, Van Pul A, Van der Hoek W, Heederik D. Atmospheric dispersion modelling of bioaerosols that are pathogenic to humans and livestock - A review to inform risk assessment studies. MICROBIAL RISK ANALYSIS 2016; 1:19-39. [PMID: 32289056 PMCID: PMC7104230 DOI: 10.1016/j.mran.2015.07.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 06/25/2015] [Accepted: 07/17/2015] [Indexed: 05/21/2023]
Abstract
In this review we discuss studies that applied atmospheric dispersion models (ADM) to bioaerosols that are pathogenic to humans and livestock in the context of risk assessment studies. Traditionally, ADMs have been developed to describe the atmospheric transport of chemical pollutants, radioactive matter, dust, and particulate matter. However, they have also enabled researchers to simulate bioaerosol dispersion. To inform risk assessment, the aims of this review were fourfold, namely (1) to describe the most important physical processes related to ADMs and pathogen transport, (2) to discuss studies that focused on the application of ADMs to pathogenic bioaerosols, (3) to discuss emission and inactivation rate parameterisations, and (4) to discuss methods for conversion of concentrations to infection probabilities (concerning quantitative microbial risk assessment). The studies included human, livestock, and industrial sources. Important factors for dispersion included wind speed, atmospheric stability, topographic effects, and deposition. Inactivation was mainly governed by humidity, temperature, and ultraviolet radiation. A majority of the reviewed studies, however, lacked quantitative analyses and application of full quantitative microbial risk assessments (QMRA). Qualitative conclusions based on geographical dispersion maps and threshold doses were encountered frequently. Thus, to improve risk assessment for future outbreaks and releases, we recommended determining well-quantified emission and inactivation rates and applying dosimetry and dose-response models to estimate infection probabilities in the population at risk.
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Affiliation(s)
- J.P.G. Van Leuken
- Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
- Corresponding author: Centre for Infectious Disease Control, National Institute for Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, The Netherlands. Tel.: +31 30 274 2003.
| | - A.N. Swart
- Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - A.H. Havelaar
- Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
- Emerging Pathogens Institute and Animal Sciences Department, University of Florida, Gainesville, FL, United States of America
| | - A. Van Pul
- Environment & Safety (M&V), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - W. Van der Hoek
- Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - D. Heederik
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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Corzo CA, Culhane M, Dee S, Morrison RB, Torremorell M. Airborne detection and quantification of swine influenza a virus in air samples collected inside, outside and downwind from swine barns. PLoS One 2013; 8:e71444. [PMID: 23951164 PMCID: PMC3738518 DOI: 10.1371/journal.pone.0071444] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 07/03/2013] [Indexed: 11/19/2022] Open
Abstract
Airborne transmission of influenza A virus (IAV) in swine is speculated to be an important route of virus dissemination, but data are scarce. This study attempted to detect and quantify airborne IAV by virus isolation and RRT-PCR in air samples collected under field conditions. This was accomplished by collecting air samples from four acutely infected pig farms and locating air samplers inside the barns, at the external exhaust fans and downwind from the farms at distances up to 2.1 km. IAV was detected in air samples collected in 3 out of 4 farms included in the study. Isolation of IAV was possible from air samples collected inside the barn at two of the farms and in one farm from the exhausted air. Between 13% and 100% of samples collected inside the barns tested RRT-PCR positive with an average viral load of 3.20E+05 IAV RNA copies/m³ of air. Percentage of exhaust positive air samples also ranged between 13% and 100% with an average viral load of 1.79E+04 RNA copies/m³ of air. Influenza virus RNA was detected in air samples collected between 1.5 and 2.1 Km away from the farms with viral levels significantly lower at 4.65E+03 RNA copies/m³. H1N1, H1N2 and H3N2 subtypes were detected in the air samples and the hemagglutinin gene sequences identified in the swine samples matched those in aerosols providing evidence that the viruses detected in the aerosols originated from the pigs in the farms under study. Overall our results indicate that pigs can be a source of IAV infectious aerosols and that these aerosols can be exhausted from pig barns and be transported downwind. The results from this study provide evidence of the risk of aerosol transmission in pigs under field conditions.
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Affiliation(s)
- Cesar A. Corzo
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Marie Culhane
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, Saint Paul, Minnesota, United States of America
- University of Minnesota Veterinary Diagnostic Laboratory, Saint Paul, Minnesota, United States of America
| | - Scott Dee
- Pipestone Veterinary Clinic, Pipestone, Minnesota, United States of America
| | - Robert B. Morrison
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Montserrat Torremorell
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, Saint Paul, Minnesota, United States of America
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Quantification of airborne African swine fever virus after experimental infection. Vet Microbiol 2013; 165:243-51. [PMID: 23608475 DOI: 10.1016/j.vetmic.2013.03.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 02/21/2013] [Accepted: 03/01/2013] [Indexed: 10/27/2022]
Abstract
Knowledge on African Swine Fever (ASF) transmission routes can be useful when designing control measures against the spread of ASF virus (ASFV). Few studies have focused on the airborne transmission route, and until now no data has been available on quantities of ASF virus (ASFV) in the air. Our aim was to validate an air sampling technique for ASF virus (ASFV) that could be used to detect and quantify virus excreted in the air after experimental infection of pigs. In an animal experiment with the Brazil'78, the Malta'78 and Netherlands'86 isolates, air samples were collected at several time points. For validation of the air sampling technique, ASFV was aerosolised in an isolator, and air samples were obtained using the MD8 air scan device, which was shown to be suitable to detect ASFV. The half-life of ASFV in the air was on average 19 min when analysed by PCR, and on average 14 min when analysed by virus titration. In rooms with infected pigs, viral DNA with titres up to 10(3.2) median tissue culture infective dose equivalents (TCID50eq.)/m(3) could be detected in air samples from day 4 post-inoculation (dpi 4) until the end of the experiments, at dpi 70. In conclusion, this study shows that pigs infected with ASFV will excrete virus in the air, particularly during acute disease. This study provides the first available parameters to model airborne transmission of ASFV.
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Otake S, Dee S, Corzo C, Oliveira S, Deen J. Long-distance airborne transport of infectious PRRSV and Mycoplasma hyopneumoniae from a swine population infected with multiple viral variants. Vet Microbiol 2010; 145:198-208. [PMID: 20418029 DOI: 10.1016/j.vetmic.2010.03.028] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 03/20/2010] [Accepted: 03/24/2010] [Indexed: 11/17/2022]
Abstract
Airborne transport of porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M hyo) has been reported out to 4.7 km. This study attempted to determine whether this event could occur over longer distances and across multiple viral variants. To accomplish this goal, a mixed infection of 3 PRRSV variants (1-8-4, 1-18-2 and 1-26-2) and M hyo 232 was established in a source population of growing pigs. Over 21-day period, air samples were collected from the source population and at designated distances from the herd. Samples were tested for PRRSV RNA and M hyo DNA by PCR and if positive, further characterized. In exhaust air from the source population, PRRSV and M hyo were detected in 21 of 21 and 8 of 21 air samples, respectively. Five of 114 (4.4%) long-distance air samples were positive for PRRSV and 6 of 114 (5.2%) were positive for M hyo. The 5 PRRSV-positive samples were collected at 2.3, 4.6, 6.6 and 9.1 km from the herd. All contained infectious virus and were >99.2% homologous to PRRSV 1-8-4. No evidence of PRRSV 1-18-2 or 1-26-2 was detected in long-distance samples. All 6 M hyo-positive samples were 99.9% homologous to M hyo 232 and 3 samples (collected at 3.5, 6.8 and 9.2km from the herd) were infectious. These results indicate that airborne transport of PRRSV 1-8-4 and M hyo 232 occurs over longer distances than previously reported and that both pathogens remained infectious.
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Affiliation(s)
- Satoshi Otake
- Swine Disease Eradication Center, University of Minnesota, College of Veterinary Medicine, 1988 Fitch Avenue, St. Paul, MN 55108, USA
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Dee S, Otake S, Oliveira S, Deen J. Evidence of long distance airborne transport of porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae. Vet Res 2009; 40:39. [PMID: 19379664 PMCID: PMC2701181 DOI: 10.1051/vetres/2009022] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Accepted: 04/17/2009] [Indexed: 11/17/2022] Open
Abstract
The ability of porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae to be transported over long distances via the airborne route was evaluated. A source population of 300 grow-finish pigs was experimentally inoculated with PRRSV MN-184 and M. hyopneumoniae 232 and over a 50-day period, air samples were collected at designated distances from the source herd using a liquid cyclonic collector. Samples were tested for the presence of PRRSV RNA and M. hyopneumoniae DNA by PCR and if positive, further characterized. Of the 306 samples collected, 4 (1.3%) were positive for PRRSV RNA and 6 (1.9%) were positive for M. hyopneumoniae DNA. The PRRSV-positive samples were recovered 4.7 km to the northwest (NW) of the source population. Four of the M. hyopneumoniae-positive samples were obtained at the NW sampling point; 2 samples at approximately 2.3 km and the other 2 samples approximately 4.7 km from the source population. Of the remaining 2 samples, one sample was obtained at the southeast sampling point and the other at the southwest sampling point, with both locations being approximately 4.7 km from the source. The four PRRSV-positive samples contained infectious virus and were ≥ 98.8% homologous to the MN-184 isolate used to inoculate the source population. All 6 of the M. hyopneumoniae-positive samples were 99.9% homologous to M. hyopneumoniae 232. These results support the hypothesis that long distance airborne transport of these important swine pathogens can occur.
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Affiliation(s)
- Scott Dee
- Swine Disease Eradication Center, University of Minnesota College of Veterinary Medicine, St. Paul, MN 55108, USA.
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Griffin DW. Atmospheric movement of microorganisms in clouds of desert dust and implications for human health. Clin Microbiol Rev 2007; 20:459-77, table of contents. [PMID: 17630335 PMCID: PMC1932751 DOI: 10.1128/cmr.00039-06] [Citation(s) in RCA: 333] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Billions of tons of desert dust move through the atmosphere each year. The primary source regions, which include the Sahara and Sahel regions of North Africa and the Gobi and Takla Makan regions of Asia, are capable of dispersing significant quantities of desert dust across the traditionally viewed oceanic barriers. While a considerable amount of research by scientists has addressed atmospheric pathways and aerosol chemistry, very few studies to determine the numbers and types of microorganisms transported within these desert dust clouds and the roles that they may play in human health have been conducted. This review is a summary of the current state of knowledge of desert dust microbiology and the health impact that desert dust and its microbial constituents may have in downwind environments both close to and far from their sources.
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Affiliation(s)
- Dale W Griffin
- U.S. Geological Survey, St. Petersburg, Florida 33701, USA.
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Callan RJ, Van Metre DC. Viral diseases of the ruminant nervous system. Vet Clin North Am Food Anim Pract 2004; 20:327-62, vii. [PMID: 15203229 DOI: 10.1016/j.cvfa.2004.02.001] [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: 12/25/2022] Open
Abstract
This article presents the etiology, epidemiology, clinical features,and diagnosis of the primary viral neurologic diseases observed in ruminants. In general, these viral neurologic diseases are uncommon but often fatal. Rabies virus is perhaps the most important cause of encephalitis in cattle because of the public health implications. Other viral encephalitis diseases in ruminants include bovine herpesvirus encephalomyelitis, pseudorabies, malignant catarrhal fever, ovine and caprine lentiviral encephalitis, West Nile virus encephalitis, Borna disease, paramyxoviral sporadic bovine encephalomyelitis,and ovine encephalomyelitis (louping-ill).
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Affiliation(s)
- Robert J Callan
- Department of Clinical Sciences, Colorado State University, 300 West Drake Road, Fort Collins, CO 80523, USA.
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van Nes A. Mathematical modelling of pseudorabies virus (syn. Aujeszky's disease virus) outbreaks aids eradication programmes: a review. Vet Q 2001; 23:21-6. [PMID: 11205997 DOI: 10.1080/01652176.2001.9695070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
Abstract
Pseudorabies virus will be eradicated from the Netherlands if a typical infectious pig (Rind) infects, on average, less than one other pig. In this review, we used a stochastic SIR model to estimate Rind using data from the field and from experiments. Rind in sow herds was estimated to be significantly less than 1 and in rearing and finishing pigs Rind was higher than 1. However, if Rind is higher than 1, PRV can still be eradicated if one infectious herd infects less than one other herd during the period that the herd is infectious(Rherd <1). Some future developments in Dutch pig husbandry (e.g. group-housing of sows) and possible risks after halting vaccination are also quantitatively evaluated.
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Affiliation(s)
- A van Nes
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
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Abstract
Airborne transmission is of significance for a number of infectious diseases in pigs. The general principles of the airborne pathway, including aerosol production, decay and inhalation, are reviewed. Practical issues regarding aerosol sampling and sample analysis are also discussed. Details of the aerobiology of porcine diseases, including foot-and-mouth disease, Aujesky's disease, and respiratory diseases, are explained. Some additional, potentially airborne diseases are discussed in terms of the evidence for their aerosol transmission. In order to prevent airborne diseases in pigs, dust reduction, air filtration, air disinfection, vaccination and the establishment of disease-free regions could be considered.
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Affiliation(s)
- K D Stärk
- EpiCentre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
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Abstract
This article reviews the rationale for using marker vaccines and companion diagnostic tests in the eradication of pseudorabies virus (PRV). Recent advances in vaccinology and epidemiology indicate that, despite the inability to induce complete immunity, vaccination is a useful tool in the battle against PRV. This review focuses on the effectiveness of vaccination under field conditions and on herd, management and regional factors that are associated with PRV introduction or transmission.
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Affiliation(s)
- A Stegeman
- Dept. of Pathobiology and Epidemiology, Institute for Animal Science and Health (ID-DLO), Lelystad, The Netherlands
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