The origins and relationships of Newcastle disease virus (NDV) vaccine strains Hertfordshire OI) ... more The origins and relationships of Newcastle disease virus (NDV) vaccine strains Hertfordshire OI) andMukteswar, and the virulent Herts'33 were studied using partial sequence analysis of the fusion protein gene.The mesogenic strain H was obtained by egg passages of a field virus isolated in England in 1933 (later knownas Herts'33). Different lines of the strain Herts'33, however, divided into two distinct groups: genotype IV, and ahitherto undescribed lineage, which comprised the Weybridge line (Herts'33/56). Vaccine strain H and the twoclusters comprising viruses designated Herts'33 displayed 6.5 to 6.8% and 15.6 to 16.3% mutational distances,respectively, which precluded parent-offspring relationships with either of them. In contrast, the different linesof the vaccine strain Mukteswar, which was reportedly derived from an Indian field isolate in the mid-1940s,showed 98.9 to 100% sequence similarity to strain H. It is therefore probable that the two vaccines were derivedfrom the same virus stock.
Forty-five velogenic Newcastle disease virus strains isolated in Germany between 1939 and 1995 we... more Forty-five velogenic Newcastle disease virus strains isolated in Germany between 1939 and 1995 were analysed by restriction enzyme digestion and sequencing to shed light on the relationships of past epizootics. Viruses derived from the period prior to 1970 belonged to a clade (IVea) of genotype IV comprising the earliest isolates from Europe, and could be isolated until the late seventies from poultry. Essex'70-like viruses, the prototype of genotype V, were already present at the beginning of the 1970-74 epizootic and in sporadic cases thereafter, indicating that these Newcastle disease outbreaks started in Western Europe. A genotype VI (subtype VIc)isolate was obtained in the early 1980s from a single outbreak in poultry. Outbreaks between 1993-95 were again part of a Western European epizootic caused by a genotype VIIa virus that was prevalent in the Far East.
34 strains of Newcastle disease virus (NDV) isolated during epizootics in the Republic of South ... more 34 strains of Newcastle disease virus (NDV) isolated during epizootics in the Republic of South Africa and in Mozambique between 1990 and 1995, and in Bulgaria and Turkey in 1995–1997 were identified by restriction enzyme and partial sequence analysis of the fusion (F) protein gene. The majority of isolates in southern Africa and those from Bulgaria and Turkey were placed into a novel group which has been termed VIIb. Group VIIb is part of a larger genetic cluster (VII) that also includes NDV strains from the Far East and some western European countries (VIIa). The genetic distance of 7–8, 5% between genotype VIIa and VIIb viruses excludes the existence of a direct epidemiological link between recent southern African epizootics and outbreaks in either western Europe in the 1990’s or those of the Far East. Another hitherto unrecorded genotype (VIII) was also found in South Africa with descendants of putative ancestral members isolated in the 1960’s. The genetic distance of recent group VIII strains from the major epizootic genotype (VIIb) is over 11%, therefore outbreaks caused by them were epidemiologically unrelated. Genotype VIII viruses must have been maintained in South Africa by endemic infections during the past decades while group VIIb appears to be introduced more recently.
A 75% region of the F gene (between nucleotides 334 and 1682) of Newcastle disease virus (NDV) RN... more A 75% region of the F gene (between nucleotides 334 and 1682) of Newcastle disease virus (NDV) RNA was amplified by reverse transcription-polymerase chain reaction (RT-PCR). PCR products were cleaved by three restriction endonucleases and the positions of thirty cleavage sites were mapped in more than 200 NDV strains. Restriction site analysis established six major groups of NDV isolates and unique fingerprints of vaccine strains. Group I comprised lentogenic strains isolated mainly from waterfowl with some from chickens. “Old” (prior to 1960s) North American isolates of varying virulence including lentogenic and mesogenic vaccine strains belonged to group II. Group III included two early isolates from the Far East. Early European strains (Herts 33 and Italien) of the first panzootic (starting in the late 1920s) and their descendants with some modifications were placed into group IV. NDV strains isolated during the second panzootic of chickens (starting in the early 1960s) were classified into two groups. Group V included strains originating in imported psittacines and in epizootics of chickens at the early 1970s. Group VI comprised strains from the Middle East in the late 1960s and later isolates from Asia and Europe. Pigeon paramyxovirus-1 strains that were responsible for the third panzootic formed a distinct subgroup in group VI. Our grouping of NDV strains has confirmed group differences established by monoclonal antibodies. It is concluded that restriction site analysis of F gene PCR amplicons is a relatively fast, simple and reliable method for the differentiation and identification of NDV strains.
Journal of Veterinary Medicine Series B-infectious Diseases and Veterinary Public Health, 2003
Twelve vaccine batches prepared from avirulent vaccine strains of Newcastle disease virus produce... more Twelve vaccine batches prepared from avirulent vaccine strains of Newcastle disease virus produced by seven manufacturers were identified by analysis of the matrix (M) protein gene with restriction enzymes MboI and HinfI. The analyses have revealed the presence of the strain indicated by the manufacturers (namely B-1, LaSota or Ulster 2C), except in one case when the vaccine contained strain V4 Queensland instead of VGGA as indicated. In addition, several batches of both monovalent and combined vaccines containing strain LaSota of the same company consistently disclosed contamination with strain B-1. The mixed nature of the preparations was verified not only by the dual patterns of restriction fragments but also by separating the two components and identifying them individually. Restriction analysis of the M gene, by allowing positive identification of each of the lentogenic vaccine strains, should provide an improvement in controlling vaccine batches by revealing homologous contaminants or exchange of the vaccine strain.
During a 95-day study period in 1995 in Denmark, 18 ostriches in a flock of 77 ostriches and four... more During a 95-day study period in 1995 in Denmark, 18 ostriches in a flock of 77 ostriches and four emus held in quarantine died. Clinical and pathological observations did not indicate the presence of transmissible infectious disease in the flock. Management failures and indoor housing were believed to have contributed significantly to the number of deaths. Samples from 17 of the dead ostriches were examined virologically. Three isolates of avian paramyxovirus serotype 1 (APMV-1) were obtained from intestines and intestinal contents of dead ostriches submitted for laboratory investigations. In ICPI tests in day-old chicks values for the three APMV-1 isolates were in the range 1.63-1.69. Characterization by means of mouse monoclonal antibodies and by restriction site analysis revealed that the three isolates were indistinguishable and similar to APMV-1 viruses present in a simultaneous epizootic of Newcastle disease in back yard poultry in Denmark. Blood samples were taken from all live birds in the flock after 25 and 95 days of quarantine and all were negative for antibodies to APMV-1 in haemagglutination inhibition tests. All samples taken after 95 days of quarantine were also negative for antibodies to APMV-1 in serum neutralization tests performed in chicken embryo cells. Blood samples taken after 95 days of quarantine were tested in a commercial ELISA for antibodies to APMV-1. In this test 35% of the samples were positive, 35% were border line and 30% were negative.
Newcastle disease virus (NDV) strains, isolated from outbreaks during epizootics between 1992 an... more Newcastle disease virus (NDV) strains, isolated from outbreaks during epizootics between 1992 and 1996 in Western European countries, were compared by restriction enzyme cleavage site mapping of the fusion (F) protein gene between nucleotides 334 and 1682 and by sequence analysis between nucleotides 47 and 435. Both methods revealed that NDV strains responsible for these epizootics belong to two distinct genotypes. Strains derived from sporadic cases in Denmark, Sweden, Switzerland and Austria were classified into genotype VI [6], the same group which caused outbreaks in the Middle East and Greece in the late 1960’s and in Hungary in the early 1980’s. In contrast, viruses that caused epizootics in Germany, Belgium, The Netherlands, Spain and Italy could be classified into a novel genotype (provisionally termed VII), hitherto undetected in Europe. It is possible that the genotype VII viruses originated in the Far East because they showed a high genetic similarity (97%) to NDV strains isolated from Indonesia in the late 1980’s.
The origins and relationships of Newcastle disease virus (NDV) vaccine strains Hertfordshire OI) ... more The origins and relationships of Newcastle disease virus (NDV) vaccine strains Hertfordshire OI) andMukteswar, and the virulent Herts'33 were studied using partial sequence analysis of the fusion protein gene.The mesogenic strain H was obtained by egg passages of a field virus isolated in England in 1933 (later knownas Herts'33). Different lines of the strain Herts'33, however, divided into two distinct groups: genotype IV, and ahitherto undescribed lineage, which comprised the Weybridge line (Herts'33/56). Vaccine strain H and the twoclusters comprising viruses designated Herts'33 displayed 6.5 to 6.8% and 15.6 to 16.3% mutational distances,respectively, which precluded parent-offspring relationships with either of them. In contrast, the different linesof the vaccine strain Mukteswar, which was reportedly derived from an Indian field isolate in the mid-1940s,showed 98.9 to 100% sequence similarity to strain H. It is therefore probable that the two vaccines were derivedfrom the same virus stock.
Forty-five velogenic Newcastle disease virus strains isolated in Germany between 1939 and 1995 we... more Forty-five velogenic Newcastle disease virus strains isolated in Germany between 1939 and 1995 were analysed by restriction enzyme digestion and sequencing to shed light on the relationships of past epizootics. Viruses derived from the period prior to 1970 belonged to a clade (IVea) of genotype IV comprising the earliest isolates from Europe, and could be isolated until the late seventies from poultry. Essex'70-like viruses, the prototype of genotype V, were already present at the beginning of the 1970-74 epizootic and in sporadic cases thereafter, indicating that these Newcastle disease outbreaks started in Western Europe. A genotype VI (subtype VIc)isolate was obtained in the early 1980s from a single outbreak in poultry. Outbreaks between 1993-95 were again part of a Western European epizootic caused by a genotype VIIa virus that was prevalent in the Far East.
34 strains of Newcastle disease virus (NDV) isolated during epizootics in the Republic of South ... more 34 strains of Newcastle disease virus (NDV) isolated during epizootics in the Republic of South Africa and in Mozambique between 1990 and 1995, and in Bulgaria and Turkey in 1995–1997 were identified by restriction enzyme and partial sequence analysis of the fusion (F) protein gene. The majority of isolates in southern Africa and those from Bulgaria and Turkey were placed into a novel group which has been termed VIIb. Group VIIb is part of a larger genetic cluster (VII) that also includes NDV strains from the Far East and some western European countries (VIIa). The genetic distance of 7–8, 5% between genotype VIIa and VIIb viruses excludes the existence of a direct epidemiological link between recent southern African epizootics and outbreaks in either western Europe in the 1990’s or those of the Far East. Another hitherto unrecorded genotype (VIII) was also found in South Africa with descendants of putative ancestral members isolated in the 1960’s. The genetic distance of recent group VIII strains from the major epizootic genotype (VIIb) is over 11%, therefore outbreaks caused by them were epidemiologically unrelated. Genotype VIII viruses must have been maintained in South Africa by endemic infections during the past decades while group VIIb appears to be introduced more recently.
A 75% region of the F gene (between nucleotides 334 and 1682) of Newcastle disease virus (NDV) RN... more A 75% region of the F gene (between nucleotides 334 and 1682) of Newcastle disease virus (NDV) RNA was amplified by reverse transcription-polymerase chain reaction (RT-PCR). PCR products were cleaved by three restriction endonucleases and the positions of thirty cleavage sites were mapped in more than 200 NDV strains. Restriction site analysis established six major groups of NDV isolates and unique fingerprints of vaccine strains. Group I comprised lentogenic strains isolated mainly from waterfowl with some from chickens. “Old” (prior to 1960s) North American isolates of varying virulence including lentogenic and mesogenic vaccine strains belonged to group II. Group III included two early isolates from the Far East. Early European strains (Herts 33 and Italien) of the first panzootic (starting in the late 1920s) and their descendants with some modifications were placed into group IV. NDV strains isolated during the second panzootic of chickens (starting in the early 1960s) were classified into two groups. Group V included strains originating in imported psittacines and in epizootics of chickens at the early 1970s. Group VI comprised strains from the Middle East in the late 1960s and later isolates from Asia and Europe. Pigeon paramyxovirus-1 strains that were responsible for the third panzootic formed a distinct subgroup in group VI. Our grouping of NDV strains has confirmed group differences established by monoclonal antibodies. It is concluded that restriction site analysis of F gene PCR amplicons is a relatively fast, simple and reliable method for the differentiation and identification of NDV strains.
Journal of Veterinary Medicine Series B-infectious Diseases and Veterinary Public Health, 2003
Twelve vaccine batches prepared from avirulent vaccine strains of Newcastle disease virus produce... more Twelve vaccine batches prepared from avirulent vaccine strains of Newcastle disease virus produced by seven manufacturers were identified by analysis of the matrix (M) protein gene with restriction enzymes MboI and HinfI. The analyses have revealed the presence of the strain indicated by the manufacturers (namely B-1, LaSota or Ulster 2C), except in one case when the vaccine contained strain V4 Queensland instead of VGGA as indicated. In addition, several batches of both monovalent and combined vaccines containing strain LaSota of the same company consistently disclosed contamination with strain B-1. The mixed nature of the preparations was verified not only by the dual patterns of restriction fragments but also by separating the two components and identifying them individually. Restriction analysis of the M gene, by allowing positive identification of each of the lentogenic vaccine strains, should provide an improvement in controlling vaccine batches by revealing homologous contaminants or exchange of the vaccine strain.
During a 95-day study period in 1995 in Denmark, 18 ostriches in a flock of 77 ostriches and four... more During a 95-day study period in 1995 in Denmark, 18 ostriches in a flock of 77 ostriches and four emus held in quarantine died. Clinical and pathological observations did not indicate the presence of transmissible infectious disease in the flock. Management failures and indoor housing were believed to have contributed significantly to the number of deaths. Samples from 17 of the dead ostriches were examined virologically. Three isolates of avian paramyxovirus serotype 1 (APMV-1) were obtained from intestines and intestinal contents of dead ostriches submitted for laboratory investigations. In ICPI tests in day-old chicks values for the three APMV-1 isolates were in the range 1.63-1.69. Characterization by means of mouse monoclonal antibodies and by restriction site analysis revealed that the three isolates were indistinguishable and similar to APMV-1 viruses present in a simultaneous epizootic of Newcastle disease in back yard poultry in Denmark. Blood samples were taken from all live birds in the flock after 25 and 95 days of quarantine and all were negative for antibodies to APMV-1 in haemagglutination inhibition tests. All samples taken after 95 days of quarantine were also negative for antibodies to APMV-1 in serum neutralization tests performed in chicken embryo cells. Blood samples taken after 95 days of quarantine were tested in a commercial ELISA for antibodies to APMV-1. In this test 35% of the samples were positive, 35% were border line and 30% were negative.
Newcastle disease virus (NDV) strains, isolated from outbreaks during epizootics between 1992 an... more Newcastle disease virus (NDV) strains, isolated from outbreaks during epizootics between 1992 and 1996 in Western European countries, were compared by restriction enzyme cleavage site mapping of the fusion (F) protein gene between nucleotides 334 and 1682 and by sequence analysis between nucleotides 47 and 435. Both methods revealed that NDV strains responsible for these epizootics belong to two distinct genotypes. Strains derived from sporadic cases in Denmark, Sweden, Switzerland and Austria were classified into genotype VI [6], the same group which caused outbreaks in the Middle East and Greece in the late 1960’s and in Hungary in the early 1980’s. In contrast, viruses that caused epizootics in Germany, Belgium, The Netherlands, Spain and Italy could be classified into a novel genotype (provisionally termed VII), hitherto undetected in Europe. It is possible that the genotype VII viruses originated in the Far East because they showed a high genetic similarity (97%) to NDV strains isolated from Indonesia in the late 1980’s.
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Papers by Béla Lomniczi
held in quarantine died. Clinical and pathological observations did not indicate the presence of transmissible
infectious disease in the flock. Management failures and indoor housing were believed to have
contributed significantly to the number of deaths. Samples from 17 of the dead ostriches were examined
virologically. Three isolates of avian paramyxovirus serotype 1 (APMV-1) were obtained from intestines
and intestinal contents of dead ostriches submitted for laboratory investigations. In ICPI tests in day-old
chicks values for the three APMV-1 isolates were in the range 1.63-1.69. Characterization by means of
mouse monoclonal antibodies and by restriction site analysis revealed that the three isolates were
indistinguishable and similar to APMV-1 viruses present in a simultaneous epizootic of Newcastle disease
in back yard poultry in Denmark. Blood samples were taken from all live birds in the flock after 25 and
95 days of quarantine and all were negative for antibodies to APMV-1 in haemagglutination inhibition
tests. All samples taken after 95 days of quarantine were also negative for antibodies to APMV-1 in serum
neutralization tests performed in chicken embryo cells. Blood samples taken after 95 days of quarantine
were tested in a commercial ELISA for antibodies to APMV-1. In this test 35% of the samples were
positive, 35% were border line and 30% were negative.
held in quarantine died. Clinical and pathological observations did not indicate the presence of transmissible
infectious disease in the flock. Management failures and indoor housing were believed to have
contributed significantly to the number of deaths. Samples from 17 of the dead ostriches were examined
virologically. Three isolates of avian paramyxovirus serotype 1 (APMV-1) were obtained from intestines
and intestinal contents of dead ostriches submitted for laboratory investigations. In ICPI tests in day-old
chicks values for the three APMV-1 isolates were in the range 1.63-1.69. Characterization by means of
mouse monoclonal antibodies and by restriction site analysis revealed that the three isolates were
indistinguishable and similar to APMV-1 viruses present in a simultaneous epizootic of Newcastle disease
in back yard poultry in Denmark. Blood samples were taken from all live birds in the flock after 25 and
95 days of quarantine and all were negative for antibodies to APMV-1 in haemagglutination inhibition
tests. All samples taken after 95 days of quarantine were also negative for antibodies to APMV-1 in serum
neutralization tests performed in chicken embryo cells. Blood samples taken after 95 days of quarantine
were tested in a commercial ELISA for antibodies to APMV-1. In this test 35% of the samples were
positive, 35% were border line and 30% were negative.