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1.
Genetic typing of recent classical swine fever virus isolates from Croatia   总被引:1,自引:0,他引:1  
During a period of 5 years (1997-2001) several outbreaks of classical swine fever (CSF) were recorded in Croatia. For genetic typing, fragments of 150 nucleotides within the 5'-non-translated region (5'-NTR) and 190 nucleotides within the E2 glycoprotein coding gene of nine field isolates that were derived from domestic pigs and wild boars were used. For better epizootiological understanding, isolates from other European countries were included in the study. The results show that the isolates belong to subgroups 2.1 and 2.3 of CSF virus. Isolates from subgroup 2.1 were collected from domestic pigs during sporadic outbreaks in June 1997 and are genetically closely related. A genomic similarity between these isolates and CSF virus isolates from pigs in other European countries from the same year could also be confirmed. In contrast, the isolate from October 1997 was found to be a member of subgroup 2.3, and is closely related to European CSF virus isolates from outbreaks in the last decade in Western and Central European countries. These results show that two different sources of CSF virus caused outbreaks in Croatia during the same year. Furthermore, a close relationship was found between an isolate from a domestic pig in 1999 and isolates of subgroup 2.3 that originated from Croatian wild boars.  相似文献   

2.
Reported here are the results of antigenic and genetic characterization of equine influenza strains causing local outbreaks reported in Morocco, respectively, in 1997 and 2004. The antigenic and genetic characterizations of the equine influenza virus H3N8 are reported here. The highest similarity between the HA1 nucleotide sequences of A/equine/Nador/1/1997 and those of A/equine/Rome/5/1991 and A/equine/Italy/1199/1992 demonstrate that A/equine/Nador/1/1997 belongs to the European lineage. On the other hand, A/equine/Essaouira/2/2004 and A/equine/Essaouira/3/2004 were classified in the predivergent lineage. The present work emphasizes the importance of a national influenza survey program, which requires a collaborative laboratory network to promote the collection and characterization (antigenic and genetic) of equine influenza viruses in real time.  相似文献   

3.
During the last decade several outbreaks of classical swine fever (CSF) occurred in Germany in domestic pigs and in wild boar, respectively. Two major epidemics which also affected other EU Member States were recorded. To support epidemiological investigations genetic typing was applied and virus isolates originating from different outbreaks in Germany were assigned to groups and virus types. Two genomic regions were selected for the phylogenetic analysis, namely 150 nucleotides from the 5' non-translated region (5'-NTR) and 190 nucleotides from the E2 glycoprotein gene. All German CSF virus isolates of the nineties (Group 2) were distinct from former reference strains (Group 1). Within Group 2 both genomic regions allowed to distinguish three subgroups, namely 2.1, 2.2 and 2.3. Within subgroup 2.3 five virus types could be discriminated using the 5'-NTR sequences. These are 2.3*Uelzen and 2.3*Spreda, mainly with isolates from Lower Saxony, as well as 2.3*Rostock, 2.3*Güstrow and 2.3*Spante, mainly with isolates from Eastern Germany. Analysis of the E2 gene fragment allowed a better discrimination between single isolates, but only two virus types could be defined: 2.3*MV/BB, comprising the isolates from Eastern Germany, and 2.3*NI, with the isolates from Lower Saxony. Genetic typing allowed to discriminate between isolates involved in different CSF epidemics, and was useful for tracing the origin and spread of CSF viruses. Due to the close relationship between German CSF virus isolates, epidemiological data are a prerequisite for the interpretation of the results obtained by genetic typing. In addition, at least both genomic regions suggested here should be analysed to determine the identity of a new isolate.  相似文献   

4.
Liu H  Wang Z  Wang Y  Sun C  Zheng D  Wu Y 《Avian diseases》2008,52(1):150-155
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5.
Antigenic and genetic analyses of viruses from the 11 outbreaks of Newcastle disease in Great Britain, 12 of the outbreaks in Northern Ireland and the single outbreak in the Republic of Ireland which occurred in 1997, indicated that they were all essentially similar. In addition, the viruses from the British Isles were very similar to viruses isolated from three outbreaks in pheasants in Denmark between August and November 1996, from a goosander in Finland in September 1996, from an outbreak in chickens in Norway in February 1997, and from an outbreak in chickens in Sweden in November 1997. Viruses from outbreaks in other countries during 1995 to 1997 could be distinguished antigenically and/or genetically from the 1996 to 1997 Scandinavian/British Isles isolates, as could viruses responsible for two separate outbreaks in caged birds in quarantine premises in Great Britain in March 1997. Minor nucleotide differences in the 413-base region of the fusion gene and the 187-base region of the haemagglutinin-neuraminidase gene sequenced in this study allowed the 1996 to 1997 Scandinavian/British Isles isolates to be divided into groups. These groups broadly corresponded to the clusters of disease outbreaks, but suggested that the discrete outbreak in Scotland was probably the result of virus spread from Northern Ireland. Overall, the antigenic and genetic analyses of these viruses were consistent with the theory that the virus was introduced into the British Isles by migratory birds moving from north-east Europe. However, it was not possible to rule out other sources, such as the movement of pheasants from Denmark.  相似文献   

6.
Genetic variability of encephalomyocarditis virus (EMCV) isolates   总被引:4,自引:0,他引:4  
In order to evaluate the variability of encephalomyocarditis virus (EMCV), field isolates originating from different European regions and inducing different clinical pictures in pigs have been molecularly characterised. The regions targeted were the poly(C) tract, a part of the 5'-UTR (360 nucleotides), the Leader gene (201 nucleotides), the complete capsid coding region (2502 nucleotides), the 2A gene (403 nucleotides), the end of the 3D polymerase gene (305 nucleotides) and the 3'-UTR (123 nucleotides). Analyses have also been performed on a virulent field isolate, which had been subjected to serial passages in vivo and in vitro resulting, in the case of the in vitro passaged virus, in attenuation, as demonstrated by animal experiments. The present study shows that different clinical pictures, such as acute fatal myocarditis or reproductive failure, may not only be caused by EMCV isolates which are genetically diverse but also by the same isolate. Thus no correlation could be demonstrated between genotype and clinical disease. However, the European isolate which showed the highest genetic divergence also gave rise to a more complex clinical picture. Despite EMCV having been isolated from cases of acute fatal myocarditis in pigs in certain areas of the world for many years, clinical disease, including a variety of clinical pictures and pathogenicity, has only been recognised in Europe since 1986 and thus it can be considered an emerging disease in this region. These findings, associated with the reported phenotype changes of the virus under environmental changes (passages), along with its wide distribution among vertebrate species (including higher primates), shows the validity of considering EMCV as a potential pathogen for recipients in xenotransplantation.  相似文献   

7.
Molecular epidemiology of classical swine fever in Italy   总被引:5,自引:0,他引:5  
To gain an insight into the molecular epidemiology of classical swine fever (CSF) in Italy, virus isolates originating from outbreaks that occurred between 1985 and 2000 in wild boar or in domestic pigs in mainland Italy and in Sardinia were analysed by genetic typing. For this, a fragment (190 nucleotides) of the E2 glycoprotein gene was sequenced and phylogenetic analyses were performed, including older Italian isolates and isolates from recent outbreaks in Europe for comparison. The results show that in mainland Italy, several independent epidemiological events occurred in the last decade. In the north of the country, viruses of genotype 2.2 have persisted in wild boar, causing sporadic outbreaks in domestic pigs. In contrast, viruses of subgroups 2.1 and 2.3 appeared only intermittently in different regions of the mainland. In 1997, classical swine fever virus (CSFV) isolates belonging to the subgroup 2.1 and genetically and epidemiologically related to the Dutch isolate in Venhorst, affected domestic pigs exclusively. The isolates of subgroup 2.3, derived from wild boar as well as from domestic pigs were closely related to isolates from Germany and Poland. In Sardinia, CSF is an endemic in wild boar and affects domestic pigs also. Genetic typing showed that viruses of subgroups 1.1 and 2.3 have been present, the last ones being unrelated to the mainland viruses of the same subgroup. Due to the large quantities of pig and wild boar meat imported in some parts of Italy, it cannot be established if these viruses were always present in either the mainland or Sardinia, or if they represent recent introductions.  相似文献   

8.
Sixteen classical swine fever virus (CSFV) field isolates from outbreaks of classical swine fever from the period between February 1997 and March 1998 in the Netherlands were sequence analysed. Parts of the 5' noncoding region (5'NCR) and the E1/E2 gene were sequenced after RT-PCR. The obtained sequences were compared with isolates of recent outbreaks in Europe and those of former outbreaks in the Netherlands. Sequence alignment of the 5'NCR region (321 bp) revealed that the isolates of the Dutch outbreak of 1997-1998 were closely linked to an isolate of the CSF outbreak that started in Paderborn, Germany in 1996. A relatively large fragment of the E1/E2 gene of 850 bp, including the antigenic region of E2, which is one of the most variable regions of the CSFV genome, was sequenced to determine whether this region can be used for epidemiology within an epizootic. Epidemiological tracing of transmission of virus was followed, starting from the first isolate and a line of five generations of viruses was analysed. Besides this, new isolates which could not be epidemiologically linked to preceding ones were also characterised. Differences between the isolates of the Dutch outbreak were minor both for the linked as well as for the non-linked isolates, indicating that all isolates have a common origin. Furthermore, our data show for the first time the genetic stability of CSFV even in the highly variable antigenic region of the E2 gene during a major epidemic lasting more than 1 year.  相似文献   

9.
A selection of 43 bovine viral diarrhoea viruses isolated from mainly persistently infected cattle on 23 Slovenian farms between 1997 and 2001 were characterised genetically. Viral RNA was extracted from infected cell cultures, reverse transcribed and amplified by PCR with primers targeting the 5'-UTR and the N(pro) gene, followed by direct sequencing of purified PCR products obtained for both genomic regions. The N(pro) sequences provided the best genetic resolution, and gave also higher statistical support for phylogenetic classification of the viruses. Thirty-eight of the Slovenian isolates were of genetic subtypes 1d and 1f, four were 1b, and one subtype 1g. No BVDV type 2 viruses were found. This genetic prevalence matched those previously reported for neighbouring countries, as opposed to findings reported for more distant European countries, e.g. France, Spain and the UK. From eight cattle herds several virus isolates were analysed; with one exception all isolates from each herd were of the same genetic group. Extended sequencing of the N(pro) and part of the C gene of virus isolates with identical 5'-UTR sequences allowed differentiation between isolates obtained at different times from one herd.  相似文献   

10.
OBJECTIVE: To identify cytocidal viruses and Pasteurella spp that could be isolated from cattle involved in 2 natural outbreaks of shipping fever. ANIMALS: 105 and 120 castrated male 4- to 8-month-old feedlot cattle involved in 1997 and 1998 outbreaks, respectively. PROCEDURES: Nasal swab specimens and blood samples were collected, and cattle were vaccinated on arrival at an order-buyer barn from 4 local auction houses. Four days later, they were transported to a feedlot, and additional nasal swab specimens and blood samples were collected. Nasal swab specimens were submitted for virus isolation and bacterial culture; blood samples were submitted for measurement of respiratory bovine coronavirus (RBCV) hemagglutinin inhibition titers. RESULTS: 93 of 105 cattle and 106 of 120 cattle developed signs of respiratory tract disease during 1997 and 1998, respectively, and RBCV was isolated from 81 and 89 sick cattle, respectively, while at the order-buyer's barn or the day after arrival at the feedlot. During the 1997 outbreak, bovine herpesvirus 1 was isolated from 2 cattle at the order-buyer's barn and from 5 cattle 7 and 14 days after arrival at the feedlot, and parainfluenza virus 3 was isolated from 4 cattle 14 days after arrival at the feedlot. During the 1998 outbreak, bovine herpesvirus 1 was isolated from 2 cattle at the order-buyer's barn and on arrival at the feedlot and from 5 cattle 7 and 14 days after arrival at the feedlot, and parainfluenza virus 3 was isolated from 1 animal the day of, and from 18 cattle 7 and 14 days after, arrival at the feedlot. Pasteurella spp was cultured from 4 and 6 cattle at the order-buyer's barn and from 92 and 72 cattle on arrival at the feedlot during the 1997 and 1998 outbreaks, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that RBCV may play a causative role in outbreaks of shipping fever in cattle. More than 80% of the sick cattle shed RBCV at the beginning of 2 outbreaks when the Pasteurella spp infection rate was low.  相似文献   

11.
Over the last years, several outbreaks of virulent systemic feline calicivirus (VS-FCV) infection have been described in the USA and several European countries. The paper describes two outbreaks of VS-FCV infection in cats in Germany. Data concerning clinical, laboratory, and histopathological features ofVS-FCV infection were collected from two outbreaks affecting 55 and 4 cats, respectively. Presence of feline calicivirus was confirmed by PCR followed by sequencing of the PCR-products. Clinical signs were variable, including severe upper respiratory tract infection, dyspnoea, oral and footpad ulceration, facial oedema, enteritis, pneumonia, bleeding disorder, high fever, and icterus. Both outbreaks were characterized by a high mortality rate.The present report describes the first documented outbreaks of VS-FCV infection in cats in Germany. Clinical and histopathological features are comparable to outbreaks described in the USA and Europe. However, phylogenetic analysis of the virus genome suggests that virus strains involved in these outbreaks were different from each other and from virulent strains isolated before, confirming the known genetic variability of FCV.  相似文献   

12.
The classical swine fever (CSF) epidemic in the Netherlands in 1997-1998 lasted 14 months, during which 429 infected and 1300 at risk herds were culled, at an estimated economical cost of 2 billion US dollars. Despite the overwhelming scale of the epizootic, the CSF virus (CSFV) strain causing the outbreak has remained largely uncharacterized. The Dutch epizootic is epidemiologically linked to a small CSF outbreak in 1997, in Paderborn in Germany. E2 and partial 5' NTR sequencing has shown that the index Paderborn isolate, and several Dutch isolates taken during the 1997-1998 epizootic, are virtually identical, confirming that the Paderborn isolate triggered the Dutch outbreak, and furthermore showing that this single isolate was stable throughout the whole Dutch outbreak (the above reviewed in [C. Terpstra, A. J. de Smit, Veterinary Microbiol. 77 (2000) 3-15]). We determined the nucleotide sequence of the 5' NTR (by 5' RACE) and the complete open reading frame of the Paderborn isolate (GenBank AY072924). Our sequence was identical to previously published partial 5'NTR and E2 sequences for the index Paderborn 1997 and Dutch 1997 (Venhorst) isolates, confirming the identity of the virus we sequenced. Phylogenetic analysis based on the complete open reading frame showed that Paderborn is genetically very different from common European laboratory reference strains. Neutralization studies showed that Paderborn is also antigenically very different from common laboratory strains such as Alfort 187. Paderborn is the only recent European CSFV field isolate for which a complete sequence is available, and given Paderborns genetic and antigenic uniqueness, the Paderborn sequence may have practical use for diagnostic and vaccine antigen development.  相似文献   

13.
Like other influenza A viruses, equine influenza virus undergoes antigenic drift. It is therefore essential that surveillance is carried out to ensure that recommended strains for inclusion in vaccines are kept up to date. Here we report antigenic and genetic characterisation carried out on equine influenza virus strains isolated in North America and Europe over a 2-year period from 2008 to 2009. Nasopharyngeal swabs were taken from equines showing acute clinical signs and submitted to diagnostic laboratories for testing and virus isolation in eggs. The sequence of the HA1 portion of the viral haemagglutinin was determined for each strain. Where possible, sequence was determined directly from swab material as well as from virus isolated in eggs. In Europe, 20 viruses were isolated from 15 sporadic outbreaks and 5 viruses were isolated from North America. All of the European and North American viruses were characterised as members of the Florida sublineage, with similarity to A/eq/Lincolnshire/1/07 (clade 1) or A/eq/Richmond/1/07 (clade 2). Antigenic characterisation by haemagglutination inhibition assay indicated that the two clades could be readily distinguished and there were also at least seven amino acid differences between them. The selection of vaccine strains for 2010 by the expert surveillance panel have taken these differences into account and it is now recommended that representatives of both Florida clade 1 and clade 2 are included in vaccines.  相似文献   

14.
The objective of this paper is to describe the severe epidemic of classical swine fever (CSF) in The Netherlands in 1997–1998 under a policy of non-vaccination, intensive surveillance, pre-emptive slaughter and stamping out in an area which has one of the highest pig and herd densities in Europe.

The primary outbreak was detected on 4 February 1997 on a mixed sow and finishing pig herd. A total of 429 outbreaks was observed during the epidemic, and approximately 700 000 pigs from these herds were slaughtered. Among these outbreaks were two artificial insemination centres, which resulted in a CSF-suspect declaration of 1680 pig herds (mainly located in the southern part of The Netherlands). The time between introduction of CSF virus (CSFV) into the country and diagnosis of CSF in the primary outbreak was estimated to be approximately 6 weeks. It is presumed that CSFV was spread from The Netherlands to Italy and Spain via shipment of infected piglets in the beginning of February 1997, before the establishment of a total stand-still of transportation. In June 1997, CSFV is presumed to be introduced into Belgium from The Netherlands.

Pre-emptive slaughter of herds that had been in contact with infected herds or were located in close vicinity of infected herds, was carried out around the first two outbreaks. However, this policy was not further exercised till mid-April 1997, when pre-emptive slaughter became a standard operational procedure for the rest of the epidemic. In total, 1286 pig herds were pre-emptively slaughtered. (approximately 1.1 million pigs). A total of 44 outbreaks (10%) was detected via pre-emptive slaughter.

When there were clinical signs, the observed symptoms in infected herds were mainly atypical: fever, apathy, ataxia or a combination of these signs. In 322 out of 429 outbreaks (75%), detection was bases on clinical signs observed: 32% was detected by the farmer, 25% by the veterinary practitioner, 10% of the outbreaks by tracing teams and 8% by screening teams of the veterinary authorities. In 76% of the outbreaks detected by clinical signs, the farmer reported to have seen clinical symptoms for less than 1 week before diagnosis, in 22% for 1–4 weeks before diagnosis, and in 4 herds (1%) the farmer reported to have seen clinical symptoms for more than 4 weeks before diagnosis.

Transportation lorries played a major role in the transmission of CSFV before the primary outbreak was diagnosed. It is estimated that approximately 39 herds were already infected before the first measures of the eradication campaign came into force.

After the first measures to stop the spread of CSFV had been implemented, the distribution of the most likely routes of transmission markedly changed. In most outbreaks, a neighbourhood infection was indicated.

Basically, there were two reasons for this catastrophe. Firstly, there was the extent of the period between introduction of the virus in the region and detection of the first outbreak. As a result, CSFV had opportunities to spread from one herd to another during this period. Secondly, the measures initially taken did not prove sufficient in the swine- and herd-dense region involved.  相似文献   


15.
In Germany, eleven outbreaks of CSF in domestic pig holdings were reported in 2002. They occurred exclusively in regions where CSF virus circulated in the wild boar population. In ten cases the phylogenetic analysis revealed that the isolates from domestic pigs and wild boar had identical sequences in the 5' non-translated region (5'NTR). However, in one case a subtype was isolated which was slightly different from the virus subtype found in the wild boar population of that region. This case is decribed in detail. The epidemiological significance of different diagnostic methods is discussed, in particular the genetic typing of CSF virus isolates.  相似文献   

16.
In 1992, the porcine reproductive and respiratory syndrome virus (PRRSV) of European type (PRRSV-EU) was introduced in Denmark. By 1996, the virus had spread to approximately 25% of the Danish herds. In January 1996, a modified-live vaccine based on the American type of the virus (PRRSV-US) was used in replacement boars for Danish artificial insemination (AI) centres and from July 1996, the vaccine was used in PRRSV-EU infected herds for prevention of disease. Soon after vaccine introduction, PRRSV non-infected herds experienced outbreaks of disease due to infection with PRRSV-US. In this study, we investigated the risk factors (biosecurity level, animals, exposure from PRRSV-US-infected neighbour herds, semen, herd size, pig density and herd density) for infection with PRRSV-US in a cohort of 1071 sow herds; we used a nested case-control study. The retrospective observation period lasted from June 1996 (when they all were non-infected) to October 1997. Seventy-three non-vaccinated, closed sow herds became infected with the vaccine strain during this period. Each case herd was matched with two control herds from the cohort (controls had not been infected at the time of infection in the case herds). The data were analysed using a Cox-regression model. The hazard of infection increased significantly with exposure from PRRSV-US-infected neighbouring herds, purchase of animals from herds incubating PRRSV-US infection, increasing herd size and purchase of semen from boars at PRRSV-US-infected AI centres. The results are consistent with the modified-live vaccine strain spread to other herds by trade with animals and semen and by neighbour (area) transmission. We suggest that virus spread by aerosols was a frequent mode of transmission.  相似文献   

17.
Reported here are the results of antigenic and genetic characterisation of equine influenza strains causing local outbreaks reported to the Equine Diagnostic Centre in Berlin, Germany. In 2000, equine influenza virus was detected in a nasal swab from a non-vaccinated horse using a rapid diagnostic kit, but was not successfully isolated. Partial direct sequencing of the haemagglutinin (HA1) gene, indicated that the virus was a European lineage H3N8 subtype strain representative of strains isolated in several European countries during 2000. In 2002, two equine influenza viruses were isolated from nasal swabs both taken from unvaccinated horses with acute respiratory symptoms housed at the same stables. Antigenic characterisation using a panel of ferret antisera suggested that these isolates also belonged to the European lineage of H3N8 viruses. Analysis of deduced HA1 amino acid sequences confirmed that the HA1 of both isolates were identical and belonged to the European lineage. However, from phylogenetic analysis, both strains appeared to be more closely related to viruses isolated between 1989 and 1995 than to viruses isolated more recently in Europe. These results suggested that viruses with fewer changes than those on the main evolutionary lineage may continue to circulate. The importance of expanding current equine influenza surveillance efforts is emphasised.  相似文献   

18.
Yang CY  Shieh HK  Lin YL  Chang PC 《Avian diseases》1999,43(1):125-130
Three major outbreaks of Newcastle disease (ND) occurred in Taiwan in the last three decades (in 1969, 1984, and 1995). Newcastle disease viruses (NDVs) isolated in the three outbreaks, together with those isolated in 1998, were sequenced between nucleotides 47 and 435 of the fusion gene. A phylogenetic tree based on sequences obtained showed that the NDV isolated in 1969 was similar to the genotype III viruses. In contrast, all isolates in 1984 and seven of the eight isolates in 1995, together with all isolates in 1998, fell into the genotype VII. These results suggest that the 1969 outbreak of ND in Taiwan was caused by the genotype III virus, whereas the 1984 and 1995 outbreaks were caused by the genotype VII viruses. To date, the genotype VII viruses have caused many outbreaks in east Asia and western Europe. We suspect that these outbreaks have constituted the fourth panzootic of ND, which is distinct from the third panzootic caused by the "pigeon PMV-1 viruses." NDV isolated in Taiwan in 1984 was the earliest isolation of the genotype VII virus.  相似文献   

19.
Porcine circovirus type 2 (PCV2) from the Circoviridae family has recently been associated with two serious diseases of swine, post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). During 2002, several outbreaks of clinical disease in pigs with weights ranging from 10 to 70 kg occurred on four farms in different locations in Croatia. The signs were consistent with PMWS and PDNS. Apart from progressive weight loss, pneumonia and/or diarrhoea, multifocal erythematous skin lesions and dermal necrosis were also observed. The PCR results obtained from PCV2 specific oligonucleotide primers confirmed a PCV2 infection. In addition, archive samples that were classical swine fever virus positive and derived from domestic pigs during an outbreak in 1997 were included in this study and one out of the three isolates was found to be positive for PCV2. For a better epizootiological understanding, genetic typing of representative isolates was carried out and compared with available isolates reported in the GenBank databases.  相似文献   

20.
Foot and mouth disease (FMD) outbreaks in the northern part of Iraq have been reported. The outbreaks in 1998/1999 were due to type O virus and the disease was associated with significant mortalities especially in young calves and lambs. Furthermore, 10 FMD-like incidents in cattle were reported in 2002 in the three northern governorates. However, these cases were not associated with mortalities and the disease remained localized in the primary foci. Type A virus was isolated from the tested samples, which appears to belong to a genetic lineage within the Iran-96 topotype. A peste des petits ruminants (PPR) outbreak was reported on 27 July, 1998 in Faida, a border town between Ninevah and Dohuk governorates in Iraq. The disease was also reported from four villages: Azadi, Kherpe Sufla, Beibinava and Kendala Sur in northern Iraq. Outbreaks of PPR were also reported in the Aqre region of Dohuk and in Erbil and Sulaimania governorates. Although this disease had been suspected in the central and northern governorates for several years, and was known to be present in neighbouring countries, this was the first official report of PPR in the country and caused great concern. Two human cases of avian influenza (AI) were recorded in the Sulaimania Governorate in January 2006 and the virus was identified as H5N1 by the WHO collaborating laboratory in the United Kingdom. Based on clinical symptoms a number of cases were recorded in February, 2006 in Misan in South Iraq. However, further tests revealed that all these cases were not due to AI.  相似文献   

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