ABSTRACT
From domestic birds 13 strains of avian paramyxoviruses, serotype 1, and 14 strains of serotype 2 were isolated. Avian paramyxoviruses, serotype 2, differ antigenically and biologically from each other and from the prototype variant chicken/Yucaipa/California/56. The virus was also detected experimentally in birds having contact with the infected specimens. Examinations of avian blood sera revealed wide dissemination of viruses related to the chicken/Yucaipa/56 strain in domestic bird breeding farms (43.6% to 50.0% of positive birds). The detected variability of the antigenic structure of the isolates attests to the potential emergence of a pathogenic variant.
Subject(s)
Paramyxoviridae/isolation & purification , Animals , Antibodies, Viral/blood , Antigens, Viral/blood , Chickens/microbiology , Hemagglutinins, Viral/blood , Kazakhstan , Paramyxoviridae/immunology , Paramyxoviridae/pathogenicity , Poultry Diseases/immunology , Poultry Diseases/microbiology , Respirovirus Infections/immunology , Respirovirus Infections/microbiology , Respirovirus Infections/veterinary , Time Factors , Turkeys/microbiologyABSTRACT
The problems of virus carrier state in influenza are connected with two aspects of the disease: the duration of virus antigen persistence in convalescents and changes of influenza virus properties in the course of persistence. In the present study, natural influenza infection in chickens caused by influenza A/chicken/USSR/336/74 virus (Hav6H3--N2) was used to determine the duration of virus antigen persistence (up to 60 days) and the entire period of virus isolation from the survivers (up to 30 days). Administration of hydrocortisone on the 50th day of convalescence permitted to obtain from the chickens several influenza A virus isolates antigenically unrelated to the epizootic strain either in hemagglutinin or in neuraminidase. Cultivation of isolate No. 42 (Hav7Neq1) in the presence of the homologous serum yielded strain 42' which was neutralized by the serum to Hav6H3--N2 virus. The isolates differed from the epizootic virus by their biological properties: the eluting activity, pathogenesis and morphology. The above facts of antigenic variability are considered in the light of the antigenic heterogeneity of the natural virus population and the possibility of virus activation by the provoking effect of extreme conditions on the carriers of latent infection.
Subject(s)
Carrier State/veterinary , Chickens , Orthomyxoviridae Infections/veterinary , Poultry Diseases/microbiology , Animals , Antigens, Viral/isolation & purification , Carrier State/microbiology , Influenza A virus/immunology , Influenza A virus/pathogenicity , Orthomyxoviridae Infections/microbiologyABSTRACT
Data on isolation of chicken influenza virus strains in this country during epizootics in 1970--1975 are presented, and the antigenic characteristics of the isolates are described. All the strains had a mixed hemagglutinin type (GP6-H3N2) and neuraminidase H2. Neuraminidase of the strains had more marked antigenic relationship with H2 human influenza A/Singapore/57 (H2N2) virus than H2 of other human influenza virus strains. The size of KM of neuraminidase is similar in all chicken influenza virus strains their antigenic formula is suggested [A(GP6-H3N2)].
Subject(s)
Antigens, Viral , Orthomyxoviridae/immunology , Animals , Chickens/microbiology , Disease Outbreaks/veterinary , Epitopes , Hemagglutinins, Viral , Neuraminidase/immunology , Orthomyxoviridae Infections/microbiology , Orthomyxoviridae Infections/veterinary , Poultry Diseases/microbiology , USSRABSTRACT
The nucleated cells of the bone marrow of mouse, rat, guinea pig, chick, cattle and humans proved to be capable of producing interferon in vitro following induction with the Newcastle disease virus. The production of interferon by these cells was characterized by high stability. The bone marrow interferon was not inferior in its activity to the corresponding interferon prepared with the blood leukocytes or splenic cells.
Subject(s)
Bone Marrow Cells , Bone Marrow/immunology , Interferons/biosynthesis , Newcastle disease virus/growth & development , Animals , Cattle , Chickens , Guinea Pigs , Humans , In Vitro Techniques , Mice , Mice, Inbred CBA , RatsSubject(s)
Horse Diseases/microbiology , Influenza, Human/veterinary , Orthomyxoviridae/isolation & purification , Poultry Diseases/microbiology , Animals , Antibodies, Anti-Idiotypic/analysis , Antigens, Viral/analysis , Chickens , Ducks , Horses , Humans , Influenza, Human/immunology , Influenza, Human/microbiology , Orthomyxoviridae/immunology , USSRABSTRACT
Four viruses isolated from poultry in the USSR and Poland were identified as influenza A strains. One strain was closely related to fowl plague virus, the second showed an antigenic relationship to A/chicken/Scotland/59 (Hav5N1), and two others were antigenically related to A/duck/Ukraine/1/63 (Hav7Neq2) and A/duck/England/56 (Hav3Nav1). Antibodies to different strains of influenzavirus were detected in sera collected from poultry and from wild birds in the northern area of the USSR. More of the sera collected from migratory sea birds in the autumn gave HI reactions than did those collected in the spring. HI reactions were of higher titre when recent locally isolated viruses were used than with reference strains of influenzavirus. Sera collected in the autumn of 1969 from wild sea birds (mostly herring gulls, ducks, arctic loons, and long-tailed ducks) frequently showed HI activity not only with avian influenzavirus but also with A/equine/Miami/1/63 (Heq2 Neq2) and A/Hong Kong/1/68 (H3N2). The significance of these findings is discussed.
