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Author |
Sinclair, M.; Buhrmann, G.; Gummow, B. |
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Title |
An epidemiological investigation of the African horsesickness outbreak in the Western Cape Province of South Africa in 2004 and its relevance to the current equine export protocol |
Type |
Journal Article |
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Year |
2006 |
Publication |
Journal of the South African Veterinary Association |
Abbreviated Journal |
J S Afr Vet Assoc |
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Volume |
77 |
Issue |
4 |
Pages |
191-196 |
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Keywords |
African Horse Sickness/diagnosis/*epidemiology; African horse sickness virus/*isolation & purification; Animals; Ceratopogonidae/virology; Diagnosis, Differential; Disease Outbreaks/*veterinary; Female; Horses; Insect Vectors/virology; Male; Prevalence; Retrospective Studies; Sentinel Surveillance; South Africa/epidemiology; Viral Vaccines/administration & dosage |
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Abstract |
African Horsesickness (AHS) is a controlled disease in South Africa. The country is divided into an infected area and a control area. An outbreak of AHS in the control area can result in a ban of exports for at least 2 years. A retrospective epidemiological study was carried out on data collected during the 2004 AHS outbreak in the surveillance zone of the AHS control area in the Western Cape Province. The objective of this study was to describe the 2004 outbreak and compare it with the 1999 AHS outbreak in the same area. As part of the investigation, a questionnaire survey was conducted in the 30 km radius surrounding the index case. Spatial, temporal and population patterns for the outbreak are described. The investigation found that the outbreak occurred before any significant rainfall and that the main AHS vector (Culicoides imicola) was present in abundance during the outbreak. Furthermore, 63% of cases occurred at temperatures < or = 15 degrees C, the Eerste River Valley was a high risk area, only 17% of owners used vector protection as a control measure and 70% of horses in the outbreak area were protected by means of vaccination at the start of the outbreak. The study revealed that the current AHS control measures do not function optimally because of the high percentage of vaccinated horses in the surveillance zone, which results in insufficient sentinel animals and the consequent failure of the early warning system. Alternative options for control that allow continued export are discussed in the paper. |
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State Veterinarian Epidemiology, Elsenburg, South Africa. marnas@elsenburg.com |
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1019-9128 |
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Notes |
PMID:17458343 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2354 |
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Author |
Venter, G.J.; Koekemoer, J.J.O.; Paweska, J.T. |
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Title |
Investigations on outbreaks of African horse sickness in the surveillance zone in South Africa |
Type |
Journal Article |
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Year |
2006 |
Publication |
Revue Scientifique et Technique (International Office of Epizootics) |
Abbreviated Journal |
Rev Sci Tech |
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Volume |
25 |
Issue |
3 |
Pages |
1097-1109 |
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Keywords |
African Horse Sickness/*epidemiology; African horse sickness virus/genetics/*isolation & purification; Animals; Ceratopogonidae/*virology; Disease Outbreaks/*veterinary; Horses; Insect Vectors/*virology; Prevalence; Sentinel Surveillance/veterinary; South Africa/epidemiology |
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Abstract |
Confirmed outbreaks of African horse sickness (AHS) occurred in the surveillance zone of the Western Cape in 1999 and 2004, both of which led to a two-year suspension on the export of horses. Light trap surveys in the outbreak areas showed that known vector competent Culicoides species, notably C. imicola, were abundant and present in numbers equal to those in the traditional AHS endemic areas. Isolations of AHS virus serotypes 1 and 7, equine encephalosis virus, and bluetongue virus from field-collected C. imicola in the surveillance zone demonstrated that this species was highly competent and could transmit viruses belonging to different serogroups of the Orbivirus genus. Molecular identification of recovered virus isolates indicated that at least two incursions of AHS into the surveillance zone had taken place in 2004. The designation of an AHS-free zone in the Western Cape remains controversial since it can be easily compromised, as evidenced by the two recent outbreaks. In light of the results reported in the present study, the policy of maintaining a large population of unvaccinated horses in the surveillance zone should be reconsidered, as it leaves them vulnerable to infection with AHS virus, which is the most pathogenic of all equine viruses. |
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Address |
Agricultural Research Council-Onderstepoort Veterinary Institute, Private Bag X5, Onderstepoort, 0110 South Africa |
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ISSN |
0253-1933 |
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Notes |
PMID:17361773 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2355 |
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Author |
Sanchez-Vizcaino, J.M. |
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Title |
Control and eradication of African horse sickness with vaccine |
Type |
Journal Article |
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Year |
2004 |
Publication |
Developments in Biologicals |
Abbreviated Journal |
Dev Biol (Basel) |
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Volume |
119 |
Issue |
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Pages |
255-258 |
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Keywords |
African Horse Sickness/epidemiology/*prevention & control; African horse sickness virus/immunology; Animals; Disease Outbreaks/veterinary; Equidae/*virology; Horses; Insect Control; Insect Vectors/virology; Spain/epidemiology; Viral Vaccines/*administration & dosage |
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Abstract |
African horse sickness (AHS) is an infectious but no-contagious viral disease of equidae with high mortality in horses. The disease is caused by an arthropod-borne double-stranded RNA virus within the genus Orbivirus of the family Reoviridae transmitted by at least two species of Culicoides. Nine different serotypes have been described. The nine serotypes of AHS have been described in eastern and southern Africa. Only AHS serotypes 9 and 4 have been found in West Africa from where they occasionally spread into countries surrounding the Mediterranean. Examples of outbreaks that have occurred outside Africa are: in the Middle East (1959-1963), in Spain (serotype 9, 1966, serotype 4, 1987-1990), and in Portugal (serotype 4, 1989) and Morocco (serotype 4, 1989-1991). Laboratory diagnosis of AHS is essential. Although the clinical signs and lesions are characteristic, they can be confused with those of other diseases. Several techniques have been adapted for the detection of RNA segments, antibodies and antigen. Two types of vaccines have been described for AHS virus. Attenuated live vaccines (monovalent and polyvalent) for use in horses, mules and donkeys, are currently available, as well as a monovalent, serotype 4, inactivated vaccine, produced commercially but no longer available. New vaccines, including a subunit vaccine, have been evaluated experimentally. In this paper a review of the last AHS outbreaks in Spain, occurring during 1987-1990, and affecting the central and south part of the country, is presented. The role that vaccination played for the control and eradication of the disease, as well as other aspects such as climatological conditions, number of vectors and horse management, are also presented and evaluated. |
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Address |
Facultad de Veterinaria, Universidad Complutense, Madrid, Spain. jmvizcaino@vet.ucm.es |
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ISSN |
1424-6074 |
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Notes |
PMID:15742636 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2357 |
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Author |
Ward, M.P.; Ramsay, B.H.; Gallo, K. |
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Title |
Rural cases of equine West Nile virus encephalomyelitis and the normalized difference vegetation index |
Type |
Journal Article |
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Year |
2005 |
Publication |
Vector Borne and Zoonotic Diseases (Larchmont, N.Y.) |
Abbreviated Journal |
Vector Borne Zoonotic Dis |
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Volume |
5 |
Issue |
2 |
Pages |
181-188 |
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Keywords |
Animals; Biomass; Cluster Analysis; Disease Outbreaks/veterinary; Ecology; *Geographic Information Systems; Horse Diseases/*epidemiology; Horses; Indiana/epidemiology; Plants; Population Surveillance; Rural Health; Seasons; Topography, Medical/*methods; West Nile Fever/epidemiology/*veterinary |
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Abstract |
Data from an outbreak (August to October, 2002) of West Nile virus (WNV) encephalomyelitis in a population of horses located in northern Indiana was scanned for clusters in time and space. One significant (p = 0.04) cluster of case premises was detected, occurring between September 4 and 10 in the south-west part of the study area (85.70 degrees N, 45.50 degrees W). It included 10 case premises (3.67 case premises expected) within a radius of 2264 m. Image data were acquired by the Advanced Very High Resolution Radiometer (AVHRR) sensor onboard a National Oceanic and Atmospheric Administration polar-orbiting satellite. The Normalized Difference Vegetation Index (NDVI) was calculated from visible and near-infrared data of daily observations, which were composited to produce a weekly-1km(2) resolution raster image product. During the epidemic, a significant (p < 0.01) decrease (0.025 per week) in estimated NDVI was observed at all case and control premise sites. The median estimated NDVI (0.659) for case premises within the cluster identified was significantly (p < 0.01) greater than the median estimated NDVI for other case (0.571) and control (0.596) premises during the same period. The difference in median estimated NDVI for case premises within this cluster, compared to cases not included in this cluster, was greatest (5.3% and 5.1%, respectively) at 1 and 5 weeks preceding occurrence of the cluster. The NDVI may be useful for identifying foci of WNV transmission. |
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Address |
Department of Veterinary Pathobiology, Purdue University School of Veterinary Medicine, West Lafayette, Indiana, USA. mward@cvm.tamu.edu |
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English |
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ISSN |
1530-3667 |
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Notes |
PMID:16011435 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2627 |
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Author |
Munoz-Sanz, A. |
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Title |
[Christopher Columbus flu. A hypothesis for an ecological catastrophe] |
Type |
Journal Article |
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Year |
2006 |
Publication |
Enfermedades Infecciosas y Microbiologia Clinica |
Abbreviated Journal |
Enferm Infecc Microbiol Clin |
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Volume |
24 |
Issue |
5 |
Pages |
326-334 |
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Keywords |
Animals; Atlantic Islands; Birds; Chickens; Disease Outbreaks/*history; Disease Reservoirs; Disease Susceptibility; Ecology; Europe/ethnology; History, 15th Century; Horses; Humans; Indians, South American; Influenza A virus/classification/genetics/pathogenicity; Influenza in Birds/epidemiology/history/transmission/virology; Influenza, Human/epidemiology/*history/mortality/transmission; Models, Biological; Orthomyxoviridae Infections/epidemiology/history/veterinary/virology; Poultry Diseases/epidemiology/history/transmission/virology; Reassortant Viruses/genetics/pathogenicity; Species Specificity; Sus scrofa; Swine Diseases/history/transmission/virology; Terminology; West Indies/epidemiology |
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Abstract |
When Christopher Columbus and his men embarked on the second Colombian expedition to the New World (1493), the crew suffered from fever, respiratory symptoms and malaise. It is generally accepted that the disease was influenza. Pigs, horses and hens acquired in Gomera (Canary Islands) traveled in the same ship. The pigs may well have been the origin of the flu and the intermediary hosts for genetic recombination of other viral subtypes. The Caribbean archipelago had a large population of birds, the natural reservoir of the avian influenza virus. In this ecological scenario there was a concurrence of several biological elements that had never before coexisted in the New World: pigs, horses, the influenza virus and humans. We propose that birds are likely to have played an important role in the epidemiology of the flu occurring on the second Colombian trip, which caused a fatal demographic catastrophe, with an estimated mortality of 90% among the natives. |
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Address |
Unidad de Patologia Infecciosa, Hospital Universitario Infanta Cristina, Servicio Extremeno de Salud, Universidad de Extremadura, Badajoz, Espana. infectio@unex.es |
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Spanish |
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Original Title |
La gripe de Cristobal Colon. Hipotesis sobre una catastrofe ecologica |
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ISSN |
0213-005X |
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Notes |
PMID:16762260 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2624 |
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Author |
Dargatz, D.A.; Traub-Dargatz, J.L. |
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Title |
Multidrug-resistant Salmonella and nosocomial infections |
Type |
Journal Article |
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Year |
2004 |
Publication |
The Veterinary Clinics of North America. Equine Practice |
Abbreviated Journal |
Vet Clin North Am Equine Pract |
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Volume |
20 |
Issue |
3 |
Pages |
587-600 |
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Keywords |
Animals; Anti-Bacterial Agents/*pharmacology; Cross Infection/prevention & control/*veterinary; Disease Outbreaks/prevention & control/veterinary; Drug Resistance, Bacterial; *Drug Resistance, Multiple, Bacterial; Horse Diseases/*drug therapy/transmission; Horses; Infection Control/methods; Microbial Sensitivity Tests/veterinary; Salmonella/*drug effects; Salmonella Infections, Animal/*drug therapy/transmission |
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Abstract |
Nosocomial infections are a serious threat to optimum patient care. In addition, nosocomial infections can have far-reaching consequences for the hospital personnel and the financial aspects of the hospital. Nosocomial infections with Salmonella spp have been described among hospitalized equine populations more frequently than any other agent. Salmonella spp associated with hospitalized equids often possess more antimicrobial resistance determinants than do Salmonella spp isolated from healthy horses in the general population. There is little evidence to suggest that resistant salmonellae are more virulent than nonresistant forms. MDR forms of Salmonella complicate the selection of appropriate antimicrobials when they are indicated, however. Furthermore, the use of some antimicrobials may apply selection pressure toward enhanced ability of MDR Salmonella to colonize equine patients. Further research should help to elucidate the risky uses of antimicrobials in the hospital setting and define the role of disinfectants and treatments such as NSAIDs in the ecology of MDR forms of nosocomial infections, including Salmonella. In the meantime, thoughtful selection of when and how to use antimicrobials in equine patients, together with deliberate selection of which antimicrobials to use based on monitoring data and other factors, such as safety and spectrum, is advised. |
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Address |
Animal and Plant Health Inspection Service, Veterinary Services, Centers for Epidemiology and Animal Health, United States Department of Agriculture, 2150 Centre Avenue, Building MS 2E7, Fort Collins, CO 80521, USA. david.a.dargatz@aphis.usda.gov |
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English |
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ISSN |
0749-0739 |
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Notes |
PMID:15519820 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2632 |
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Author |
Dauphin, G.; Zientara, S.; Zeller, H.; Murgue, B. |
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Title |
West Nile: worldwide current situation in animals and humans |
Type |
Journal Article |
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Year |
2004 |
Publication |
Comparative Immunology, Microbiology and Infectious Diseases |
Abbreviated Journal |
Comp Immunol Microbiol Infect Dis |
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Volume |
27 |
Issue |
5 |
Pages |
343-355 |
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Keywords |
Americas/epidemiology; Animals; Birds/virology; Culex/*virology; *Disease Outbreaks; Disease Reservoirs; Europe/epidemiology; Horses/virology; Humans; Insect Vectors/*virology; Middle East/epidemiology; West Nile Fever/*epidemiology/*veterinary/virology; West Nile virus/*growth & development |
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Abstract |
West Nile (WN) virus is a mosquito-borne flavivirus that is native to Africa, Europe, and Western Asia. It mainly circulates among birds, but can infect many species of mammals, as well as amphibians and reptiles. Epidemics can occur in rural as well as urban areas. Transmission of WN virus, sometimes involving significant mortality in humans and horses, has been documented at erratic intervals in many countries, but never in the New World until it appeared in New York City in 1999. During the next four summers it spread with incredible speed to large portions of 46 US states, and to Canada, Mexico, Central America and the Caribbean. In many respects, WN virus is an outstanding example of a zoonotic pathogen that has leaped geographical barriers and can cause severe disease in human and equine. In Europe, in the past two decades there have been a number of significant outbreaks in several countries. However, very little is known of the ecology and natural history of WN virus transmission in Europe and most WN outbreaks in humans and animals remain unpredictable and difficult to control. |
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Address |
AFSSA Alfort, UMR1161 (INRA-AFSSA-ENVA), 22 rue Pierre Curie, BP 63, 94703 Maisons-Alfort Cedex, France |
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English |
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ISSN |
0147-9571 |
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Notes |
PMID:15225984 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2635 |
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Author |
Endy, T.P.; Nisalak, A. |
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Title |
Japanese encephalitis virus: ecology and epidemiology |
Type |
Journal Article |
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Year |
2002 |
Publication |
Current Topics in Microbiology and Immunology |
Abbreviated Journal |
Curr Top Microbiol Immunol |
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Volume |
267 |
Issue |
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Pages |
11-48 |
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Keywords |
Animals; Birds/virology; Climate; Culicidae/virology; Disease Outbreaks/history; Ecosystem; Encephalitis Virus, Japanese/*pathogenicity; Encephalitis, Japanese/*epidemiology/*etiology/history/transmission; History, 20th Century; Horses/virology; Humans; Insect Vectors; Japan/epidemiology; Risk Factors; Swine/virology; Thailand/epidemiology; Viral Vaccines/pharmacology |
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Address |
Department of Virology, United States Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), 315/6 Rajvithi Road, Bangkok 10400, Thailand |
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English |
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ISSN |
0070-217X |
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Notes |
PMID:12082986 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2643 |
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Author |
Marfin, A.A.; Petersen, L.R.; Eidson, M.; Miller, J.; Hadler, J.; Farello, C.; Werner, B.; Campbell, G.L.; Layton, M.; Smith, P.; Bresnitz, E.; Cartter, M.; Scaletta, J.; Obiri, G.; Bunning, M.; Craven, R.C.; Roehrig, J.T.; Julian, K.G.; Hinten, S.R.; Gubler, D.J. |
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Title |
Widespread West Nile virus activity, eastern United States, 2000 |
Type |
Journal Article |
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Year |
2001 |
Publication |
Emerging Infectious Diseases |
Abbreviated Journal |
Emerg Infect Dis |
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Volume |
7 |
Issue |
4 |
Pages |
730-735 |
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Keywords |
Animals; Bird Diseases/epidemiology/virology; Culicidae/virology; *Disease Outbreaks; Ecology; Horse Diseases/epidemiology/virology; Horses; Humans; Population Surveillance; Songbirds/virology; United States/epidemiology; West Nile Fever/*epidemiology/veterinary/virology; *West Nile virus |
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Abstract |
In 1999, the U.S. West Nile (WN) virus epidemic was preceded by widespread reports of avian deaths. In 2000, ArboNET, a cooperative WN virus surveillance system, was implemented to monitor the sentinel epizootic that precedes human infection. This report summarizes 2000 surveillance data, documents widespread virus activity in 2000, and demonstrates the utility of monitoring virus activity in animals to identify human risk for infection. |
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Address |
Division of Vector-Borne Infections Diseases, Centers for Disease Control and Prevention, P.O. Box 2087, Fort Collins, CO 80522, USA. aam@cdc.gov |
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Corporate Author |
ArboNET Cooperative Surveillance Group |
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English |
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Abbreviated Series Title |
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ISSN |
1080-6040 |
ISBN |
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Notes |
PMID:11585539 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2646 |
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Author |
Cilnis, M.J.; Kang, W.; Weaver, S.C. |
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Title |
Genetic conservation of Highlands J viruses |
Type |
Journal Article |
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Year |
1996 |
Publication |
Virology |
Abbreviated Journal |
Virology |
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Volume |
218 |
Issue |
2 |
Pages |
343-351 |
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Keywords |
Alphavirus/*genetics; Alphavirus Infections/transmission/veterinary/virology; Amino Acid Sequence; Animals; Base Sequence; Conserved Sequence; Disease Outbreaks; Encephalitis, Viral/veterinary/virology; *Evolution, Molecular; Horses; Molecular Sequence Data; Phylogeny; RNA, Viral/genetics; Sequence Alignment; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Turkeys; Variation (Genetics)/*genetics |
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Abstract |
We studied molecular evolution of the mosquito-borne alphavirus Highlands J (HJ) virus by sequencing PCR products generated from 19 strains isolated between 1952 and 1994. Sequences of 1200 nucleotides including portions of the E1 gene and the 3' untranslated region revealed a relatively slow evolutionary rate estimated at 0.9-1.6 x 10(-4) substitutions per nucleotide per year. Phylogenetic trees indicated that all HJ viruses descended from a common ancestor and suggested the presence of one dominant lineage in North America. However, two or more minor lineages probably circulated simultaneously for periods of years to a few decades. Strains isolated from a horse suffering encephalitis, and implicated in a recent turkey outbreak, were not phylogenetically distinct from strains isolated in other locations during the same time periods. Our findings are remarkably similar to those we obtained previously for another North American alphavirus, eastern equine encephalomyelitis virus, with which Highlands J shares primary mosquito and avian hosts, geographical distribution, and ecology. These results support the hypotheses that the duration of the transmission season affects arboviral evolutionary rates and vertebrate host mobility influences genetic diversity. |
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Department of Biology, University of California, San Diego, La Jolla 92093-0116, USA |
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English |
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0042-6822 |
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PMID:8610461 |
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Equine Behaviour @ team @ |
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2657 |
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