| interfering activity of virulent and attenuated influenza virus strains. | the interfering activity of influenza virus variants a/hong kong/1/68 (h3n202), a/victoria/35/72(h3n2-3), b/14/55 and b/ussr/69 differing in the level of their reactogenicity for adults and children was studied. an inverse relationship was established between reactogenicity of the strains and their interfering activity in the resistant chick embryo cell (cec) cultures. virulent strains did not interfere with vesicular stomatitis virus. vaccine strains used for commercial live influenza vaccine s ... | 1976 | 9798 |
| effect of influenza virus on the immune responsiveness of animals. | infection of mice with a/hong kong/1/68 (h3n2) and a/pr8/34 (h0n1) influenza virus strains resulted in a significant inhibition of the formation of antibody-producing cells in response to administration of sheep erythrocytes and a reduced capacity of spleen cells to induce "graft-versus-host" reaction. the immunosuppression caused by influenza infection was observed for a long period of time post infection (3--6 months). the extent of inhibition of antibody production depended on the dose of vir ... | 1977 | 17278 |
| antigenic glycopolypeptides ha1 and ha2 of influenza virus haemagglutinin. i. gel filtration in 6 m guanidine hydrochloride. | highly purified glycopolypeptides ha1 and ha2 were separated from bromelain-released haemagglutinin of influenza virus a/dunedin/4/73 (h3n2) by gel filtration in 6 m guanidine hydrochloride under reducing conditions. the purity of both glycopolypeptides was proved by extensive studies. despite the lack of c-terminal end, the isolated ha2 glycopolypeptide displayed some hydrophobic properties. | 1978 | 30262 |
| influence of experimental influenza infection of the eye on the course of herpetic keratitis in rabbits. | influenza virus monoinfection and combined influenza and herpes simplex virus (hsv) infection of the eye was studied in rabbits. influenza a/hong kong/1/68 (h3n2) virus caused a clinically overt disease of the eye only after inoculation into the eye chamber. the combined influenza and hsv infection of the eye induced severe iridocyclitis. the combined infection of the eye with influenza virus and hsv had a more severe course than hsv monoinfection. the occurence of influenza antibody in the lacr ... | 1978 | 35945 |
| antigenic glycopolypeptides ha1 and ha2 of influenza virus haemagglutinin. iii. reactivity with human convalescent sera. | the immune reactivity to both haemagglutinin glycopolypeptides ha1 and ha2 [prepared from bromelain-released haemagglutinin of influenza virus a/dunedin/4/73 (h3n2)], was demonstrated by both gel double immundiffusion and radioimmunoassay in human convalescent sera obtained after natural infection during influenza epidemics in 1974/75 and 1976/77. in gel double immunodiffusion, the precipitin line(s) corresponding to glycopolypeptide ha1 were always more distinct than precipin line(s) correspond ... | 1979 | 35954 |
| heterotypic interference between influenza viruses a/aichi/2/68 and b/massachusetts/1/71. | virus particles produced by mdck cells mixedly infected with 3 pfu/cell each of a/aichi/2/68 (h3n2) (aichi) and b/massachusetts/1/71 (mass) influenza viruses exclusively possessed haemagglutinin (ha) of mass, although approximately one-fifth of the mixed yield had coding potential for aichi serotype. synthesis of major viral proteins of aichi was markedly suppressed by co-infecting mass. by increasing the multiplicity of co-infecting aichi to 30 pfu/cell, interference became reciprocal. aichi in ... | 1979 | 41442 |
| antigenic variation of neuraminidase of human type a influenza (h3n2) viruses isolated in berlin (west). | after the emergence of the a/hong kong/1/68 (h3n2) strain of influenza virus antigenic variation of the hemagglutinin and neuraminidase antigens have been demonstrated leading to the identification of the variants a/england/42/72,a/port chalmers/1/73 and a/scotland/840/74. this study describes antigenic changes of neuraminidases in influenza viruses isolated since 1968 in berlin (west). a collection of 13 isolates of human type a influenza was studied in neuraminidase inhibition tests. the resul ... | 1975 | 56831 |
| swine influenza virus and the recycling of influenza-a viruses in man. | sera collected in 1967 and 1972 from people in the 0-100 age-group showed haemagglutination-inhibition (h.i.) antibody to swine virus a/iowa/15/30 (hsw1n1) in greatest number and with highest titre in people born before 1918. a slight decrease was observed from 1967 to 1972 in the number of sera with antibody to swine virus and in the height of the titres. the recently isolated a/new jersey/10/76 (hsw1n1) virus showed a result comparable to that of the swine/1930 virus in sera of 1972. on the an ... | 1976 | 59252 |
| [antigenic characteristics of chicken influenza viruses]. | 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 vir ... | 1976 | 62456 |
| a competitive-inhibition radioimmunoassay for influenza virus envelope antigens. | a double-antibody competitive-inhibition radioimmunoassay for influenza virus envelope antigens is described. a viral antigen preparation from influenza a virus recombinant mrc11 [antigenically identical to a/port chalmers/1/73 (h3n2)] consisting of haemagglutinin and neuraminidase was labelled with radioiodine. rabbit antisera were allowed to react with the labelled antigen and the resultant antigen-antibody complexes were precipitated with the appropriate antiglobulin. the competitive-inhibiti ... | 1976 | 65118 |
| return of epidemic a1 (h1n1) influenza virus. | limited outbreaks of influenza were reported in the far east of the u.s.s.r. early in november, 1977, and a week or two later in cities in siberia and the european parts of the u.s.s.r. the majority of influenza-virus isolates belonged to the h1n1 subtype of influenza-a virus, though strains of the current h3n2 subtype were also isolated. a moderate epidemic of h1n1 influenza spread throughout the country in the middle of december. mainly children over 5 years and young adults were infected. | 1978 | 75334 |
| [electrophoretic mobility of polypeptides in different strains on human influenza a and b viruses]. | the method of electrophoresis in a single polyacrylamide gel plate was used for comparative study on virion polypeptides mobility in human influenza a and b virus strains. molecular masses of individual polypeptides and their portion in the virion were determined. no variations in the migration speed of nucleoprotein (np) and membrane protein (mp) were found in strains belonging to the same genus, but there were differences in the migration speed of these proteins in the genus a and genus b. sig ... | 1978 | 80885 |
| antigenic drift in type a influenza virus: sequence differences in the hemagglutinin of hong kong (h3n2) variants selected with monoclonal hybridoma antibodies. | | 1979 | 90425 |
| [comparative study of virus adsorption properties of streptococci with reference to influenza a (h3n2) virus]. | | 1978 | 79975 |
| influenza surveillance. | the main objectives of influenza surveillance are: to measure the impact of the disease by collection and analysis of epidemiological information on morbidity and mortality, and to anticipate future epidemics and pandemics by the collection and analysis of influenza viruses. the world health organization's influenza programme is based on the collaboration of 98 national influenza centres in 70 countries and the 2 who collaborating centres in atlanta and london.epidemiological information may be ... | 1978 | 78771 |
| [antigenic specificity of influenza type a virus hemagglutinin by the method of radioimmunological quantitative analysis]. | the use of a test system o fa highly purified, antigenically homogeneus hemagglutinin of influenza a/mrc-11 virus and monospecific antiserum permitted to evaluate the potentials of competitive radioimmunoassay in model experiments investigating the antigenic characteristics and content of influenza a (h3n2) virus hemagglutinin. the method proved to be sufficiently specific to differentiate influenza virus strains by antigenic determinants of hemagglutinin, as well as highly sensitive, detecting ... | 1978 | 78586 |
| [reversion in the natural variability of influenza a virus]. | in mid-november, 1977, local outbreaks of acute respiratory diseases (ard) in institutionalized communities began to be recorded in a number of geographical zones of the ussr, and by the end of the month a general increase in the incidence was observed in some areas of the country. the epidemic outbreaks extended gradually and were characterized by moderate development involving mainly young subjects. the strains causing the epidemic had no antigenic relationship with reference a (h3n2) virus an ... | 1978 | 78585 |
| [isolation of strains of the hong kong complex (h3n2) influenza virus from nyctalus noctula bats in kazakhstan]. | four antigenically related hemagglutinating agents were isolated from pools of lungs and tracheas of nyctalus noctula bats in chick embryos. identification of the isolates by the hemagglutination inhibition, neuraminidase activity inhibition and double immunodiffusion methods revealed close antigenic relationships with a/port chalmers/73 virus. | 1979 | 158260 |
| specificity studies on cytotoxic thymus-derived lymphocytes reactive with influenza virus-infected cells: evidence for dual recognition of h-2 and viral hemagglutinin antigens. | cytotoxic thymus-derived (t) lymphocytes were readily detected in spleens of mice inoculated intranasally with mouse-adapted a/port chalmers (h3n2), a/england (h3n2), a/pr/8 (h0n1), and b/hong kong influenza viruses. t-cell-mediated lysis of h-2 compatible target cells infected with the strain of virus used to immunize the mice was considerably higher than lysis of either syngeneic cells infected with a different strain of influenza virus or allogeneic cells infected with the immunizing strain o ... | 1977 | 70788 |
| results of virological and serological studies of three influenza a hong-kong epidemics in leningrad. | an analysis of morbidity of the population in the course of 3 influenza a/hong-kong epidemics showed a pronounced decrease in influenza affection of adult population in the last epidemic in 1971--1972. comparative studies of the diagnostic value of cfr and hit demonstrated identical sensitivity of cfr as a method of influenza diagnostics in both the epidemic and interepidemic periods. hit was suitable for the detection of influenza only in the epidemic period. in the interepidemic period, the pe ... | 1976 | 61243 |
| serological evidence and isolation of a virus closely related to the human a/hong kong/68 (h3n2) strain in swine populations in czechoslovakia in 1969-1972. | | 1976 | 60851 |
| geographical distribution of swine (hsw1n1) and hong kong (h3n2) influenza virus variants in pigs in southeast asia. | influenza viruses of the hsw1n1 and h3n2 subtypes were isolated in hong kong from pigs originating from hong kong, people's republic of china (prc), singapore, and taiwan. the h3n2 isolates were from pigs from hong kong and prc, whereas the hsw1n1 isolates were from pigs from hong kong, prc, singapore and taiwan. the hemagglutinins of the h3n2 isolates were similar to those of the earlier a/hong kong/1/68 and a/port chalmers/1/73 variants from man. the hsw1n1 isolates were similar to the human a ... | 1979 | 218894 |
| comparison of different tissue cultures for isolation and quantitation of influenza and parainfluenza viruses. | rhesus and cynomolgus monkey kidney tissue cultures and two continuous lines, madin-darby canine kidney (mdck) and llc-mk2, were compared in titrations and isolations of influenza and parainfluenza viruses. tube cultures were inoculated with laboratory virus strains or stored patient specimens and observed for hemadsorption. trypsin was added to the medium of the continuous lines to increase sensitivity. all four tissue cultures gave similar titers of influenza a/ussr (h1n1), a/texas (h3n2), and ... | 1979 | 227920 |
| influenza virus subunit vaccines. ii. immunogenicity and original antigenic sin in humans. | subunit vaccines containing hemagglutinin, neuraminidase, and nucleocapsids of a/port chalmers/1/73 (h3n2) influenza virus were prepared after treatment of purified virus with ammonium deoxycholate. the immunogenicity of these subunits and the response to the common and specific antigenic determinants on the hemagglutinin subunits were studied in man. the subunits were as immunogenic in man as intact inactivated influenza virus vaccine at an equivalent concentration. booster doses of antigen did ... | 1976 | 59787 |
| wrl 105 strain (h3n2) live attenuated influenza vaccine: acceptability, reactivity, and antibody response in normal, bronchitic, and geriatric volunteers. | the acceptability, reactivity, and antibody responses of recombinant wrl 105 strain, live, attenuated influenza virus vaccine administered intranasally were studied in seventeen normal adults, and in seventeen bronchitic and twenty-one geriatric volunteers. the effect on peak flow and 1-second forced expiratory volume (f.e.v.1) on the 3rd, 5th, and 7th days after vaccination was measured in the bronchitic and normal groups. seroconversion occurred in 80% to tht homologous virus, in 40.6% to a/vi ... | 1976 | 58306 |
| [isolation of surface antigens of influenza virus a/hong kong 1/68 (h3n2) by density gradient fractionation with a new carboxypolypeptidase (author's transl)]. | isolation of pure neuraminidase and hemagglutinin from influenza virus a/hong kong 1/68 (h3n2) can be achieved using the coupled action of a new carboxypolypeptidase from streptomyces fradiae and sodium dodecyl sulfate (sds). biochemical, physical and physico-chemical studies showed that the two molecules are in pure form and of glycoproteic nature. | 1975 | 238492 |
| polymorphism of human blood groups and incidence of influenza a/hong kong (h3n2). | during three epidemics of influenza a/hong kong (h3n2) and experimentally in vaccines, the relation between influenza infection and abo, rh and mn blood groups was studied. examinations of 2760 patients with laboratory-confirmed diagnosis of influenza and 749 persons vaccinated with live influenza vaccine showed that individuals of blood groups o and b were susceptible to influenza 1.67 and 1.20 times more, respectively, than individuals of blood group a. the difference in incidence was most man ... | 1975 | 241245 |
| the laboratory surveillance of influenza epidemics in the united kingdom 1968-1976. | the extensive laboratory investigations of respiratory disease in the u.k. over many years have demonstrated the frequency with which influenza viruses, both a and b, are found each winter. only rarely are none isolated. these findings correlate well with other indicators of influenza such as increases in sickness benefit claims and in deaths attributed to influenza and pneumonia. however, outside these demonstrable peaks of incidence influenza viruses have been found to circulate over considera ... | 1977 | 267671 |
| diversity of the antibody response to the different antigenic determinants on the hemagglutinin subunits of influenza viruses. | sera from rabbits hyperimmunized with hemagglutinin (ha) subunits isolated from the a/port chalmers/73 (h3n2)strain of influenza virus showed great differences in their cross-reactions with different strains of influenza virus. in hemagglutination-inhibition tests, some sera reacted to about the same titer with a/port chalmers/73 and a/hong kong/68 viruses, suggesting that these two strains were very closely related. other sera, which reacted to high titer with a/port chalmers/73 virus, had only ... | 1976 | 55438 |
| the relative potencies of anti-influenza compounds. | the relative potencies of some standard anti-influenza compounds have been examined in vitro by plaque reduction in calf kidney cells, and in vivo by reduction in virus titers of the lungs of infected mice. strains belonging to the four subtypes h0n1, h1n1, h2n2, and h3n2 were employed to compare the activity of amantadine hydrochloride and ribavirin. in vitro for all strains except a/nws/oo(h0n1) amantadine hydrochloride was 3-4 times more active than ribavirin. in vivo with sensitive strains a ... | 1977 | 280137 |
| [age profile of the antihemagglutinins and antineuraminidase antibodies in type a influenza (author's transl)]. | antineuraminidase and antihemagglutinating antibody studies were carried out in parallel in sera from subjects born in bulgaria in 1968-1972, 1956-1960, 1946-1950, 1925-1935 and 1917-1920. it was found that the amount of both antineuraminidase and antihemagglutinating antibody in sera from normal subjects could vary depending upon the year of birth and the strain used for the test. the antibody spectrum was most narrow in children under 4 and wider in subjects born before 1925. serograms of the ... | 1975 | 54996 |
| recombinant wrl 105 strain live attenuated influenza vaccine. immunogenicity, reactivity, and transmissibility. | the immunogenicity, reactivity, and transmissibility of recombinant wrl 105 (h3n2) (a/okuda/57xa/finland/4/74) strain live attenuated influenza virus vaccine were studied in adult male volunteers in a residential community in rural england. thirteen volunteers received a single dose of 10(7.0) e.i.d.50 recombinant wrl 105 vaccine administered as nose drops, and twelve volunteers received placebo. nine (82%) of eleven volunteers with initial antibody titres of less than or equal to 1/96 showed a ... | 1975 | 51958 |
| annual examination of influenza virus infection among pigs in miyagi prefecture, japan: the appearance of hsw1n1 virus. | annual dissemination of swine and hong kong influenza viruses among hogs in miyagi prefecture, japan, was examined by virus recovery and serological tests. the serological examination revealed that two distinct influenza a viruses, h3n2 and hsw1n1, had caused dual epidemic in pigs since mid-1977. some individual sera contained antibodies against both strains. although positive sera against hong kong or swine influenza viruses appeared in the serosurvey throughout the year, the positive ratios in ... | 1979 | 41437 |
| live tissue culture influenza vaccine for oral administration. i. specific immune response to monovaccine a (h3n2) in volunteers. | oral immunization of volunteers with a live tissue culture influenza a (h3n2) vaccine induced an increase in virus neutralizing (vn), haemagglutination inhibiting (hi) and neuraminidase inhibiting (ni) antibody. the dynamics of antibody and igm and igg immunoglobulin formation in the blood depended to a great extent on their prevaccination levels. the highest per cent of seroconversions was observed after the 3rd vaccination: a 4-fold or greater rise of vn antibody was found in 80% (titre increa ... | 1979 | 35960 |
| etiology and antimicrobial therapy of acute maxillary sinusitis. | eighty-one adults with symptoms of acute sinusitis were studied by direct needle puncture and aspiration of the maxillary sinus (105 sinuses). fifty-nine bacterial strains were isolated in titers of greater than or equal to 10(4) colony-forming units/ml; streptococcus pneumoniae and haemophilus influenzae accounted for 64% of the isolates. other bacteria recovered included anaerobes (12%), neisseria species (8.5%). streptococcus pyogenes (3%), alpha-hemolytic streptococcus (3%), non-group a beta ... | 1979 | 35571 |
| radioimmunoassay of influenza a virus haemagglutinin. i. preparation and properties of radioactive 125i-labelled bromelain-released haemagglutinin. | haemagglutinin released from influenza a virus recombinant mrc11 antigenically identical to the strain a/port chalmers/1/73 (h3n2) by bromelain treatment and purified by rate zonal centrifugation (further on b-ha) was examined for eventual contamination by neuraminidase. according to specific enzymatic activities corresponding to mrc11 virus and b-ha alone respectively, b-ha contained less than 0.1% of enzymatically active neuraminidase orginally present in the virus. gel double diffusion tests, ... | 1978 | 25002 |
| [immune structure of the population of moscow to the strains of the influenza viruses a(h3n2), a(h1n1) and b circulating in 1977]. | examinations for the presence of antihemagglutinins to influenza a(h3n2), a(h1n1) and b virus strains in the sera from people of different ages collected in april-may and october-november, 1977, showed that influenza a(h1n1) virus began to circulate in the human population of moscow before the onset of an overt epidemic, in the period between june and october, 1977. this conclusion has been drawn on the basis of the absence of antihemagglutinins to a(h1n1) virus in the sera from subjects of 16-2 ... | 1979 | 311977 |
| autoantibodies in sera of rabbits immunized with influenza virus. | rabbits immunized with purified influenza a (h3n2) virus within 4 weeks developed autoantibodies of sma type (smooth muscle antibodies). in some of them also abba (antibodies against brush border of proximal renal tubuli) and ana (anti-nuclear antibodies) were detected. this autoimmune response was found to be unrelated to either the virus dose or the adjuvant used for immunization. autoantibodies were not parallel in titre with influenza antibody. | 1977 | 23669 |
| influenza virus antigens in human leukocytes after oral administration of live tissue culture influenza a monovaccine. | influenza a virus antigens were detected in leukocytes by immunofluorescence. after intravenous inoculation of the a/moscow/16/65 (h2n2) vaccine strain to chickens, cytoplasmic antigens of the virus were observed in mononuclear leukocytes from 24 to 72 hours post inoculation (p.i.). the course of antigen detectability was similar after two repeated inoculations of the virus. after oral vaccination of human volunteers with a live tissue culture influenza a monovaccine from the x-47 (h3n2) recombi ... | 1977 | 22233 |
| isolation of anti-haemagglutinin antibodies with an influenza a virus immunoadsorbent. | the x-31 strain of influenza a (h3n2) virus has been covalently bound to cnbr activated agarose for the separation of anti-haemagglutinin antibodies. the virus immunoadsorbent was used repeatedly under high ionic strength alkali buffer and acid conditions without altering appreciably its antibody binding capacity. sequential elution of bound anti-haemagglutinin antibodies with increasing concentrations of sodium iodide has enabled the physical separation of antibody populations with low and high ... | 1976 | 13126 |
| laboratory and clinical evaluation of new live influenza virus vaccines. need for minimum requirements. | recently, new methods for the selection of candidate live influenza vaccine viruses have become available. they are based on the characterization of the genetic material of these viruses and have been shown to correlate with attenuation for man. adequately attenuated viruses have been obtained from various h3n2 strains using standard methods of attenuation for each strain. these vaccine strains met the criteria for live attenuated influenza virus vaccines: they were attenuated, non-transmissibl ... | 1977 | 342307 |
| levels of immunoglobulins and antibodies to haemaglutinin and neuraminidase of influenza virus in nasal secretions after natural infection. | nasal washings (nw) from 16 influenza patients in the course of an epidemic in november and december, 1974 were examined for the presence of influenza virus, immunoglobulins (ig) and titres of haemagglutination inhibiting (hi) and neuraminidase inhibiting (ni) antibodies. influenza virus identical with a/port chalmers/1/73 (h3n2), increased levels of iga and occasionally igg, and specific antibodies were detected in the nw. the dynamics of hi and ni antibody formation did not differ substantiall ... | 1976 | 5867 |
| the specificity of the anti-haemagglutinin antibody response induced in man by inactivated influenza vaccines and by natural infection. | the anti-haemagglutinin antibody response in adult human volunteers to inactivated whole virus or tween ether split influenza a/victoria/75 (h3n2) and a/scotland/74 (h3n2) virus vaccines was investigated using antibody absorption and single-radial-haemolysis (srh) techniques. the concentrations of haemagglutinin (ha), nucleoprotein (np) and matrix (m) antigens measured by single radial diffusion (srd) and rocket immunoelectrophoresis were similar for both the whole virus and split vaccines. whol ... | 1979 | 105040 |
| swine influenza a at fort dix, new jersey (january-february 1976). iv. summary and speculation. | influenza a/new jersey/76 virus was detected at fort dix from january 19 through february 9, 1976 and infected at least 230 military personnel. thirteen hospital admissions for acute respiratory disease were associated with influenza a/new jersey infection, and additional members of index training companies may have been hospitalized with influenza a/new jersey. this virus was likely introduced into the reception center by an incoming trainee. although our studies could not eliminate the possibi ... | 1977 | 342615 |
| antibodies to the strain-specific and cross-reactive determinants of the haemagglutinin of influenza h3n2 viruses. 1. preparation of antibodies and in vitro studies. | the serological analysis of antibodies to the haemagglutinin (ha) of influenza a viruses of the hong kong (h3n2) subtype is described, using haemagglutination-inhibition, immuno-double-diffusion and single-radial-diffusion techniques. by cross-absorption of antisera to purified ha antigens, different populations of antibody molecules were obtained, which are designated strain-specific and cross-reactive and characterized in terms of their antigenic specificities for ha antigens of the homologous ... | 1979 | 93399 |
| efficacy of purified influenza subunit vaccines and relation to the major antigenic determinants on the hemagglutinin molecule. | inactivated whole-virus vaccine of influenza a/scotland/74 (h3n2) virus containing 700 or 1,400 chick cell-agglutinating (cca) units, a purified subunit vaccine of equivalent dosage, or placebo were studied in 186 adult volunteers. placebo was least reactogenic, 1,400-cca unit whole-virus vaccine was most reactogenic, and others were intermediate. vaccines were equally antigenic, and delineation of antibody specificities revealed antibody cross-reacting with a/hong kong/68 (h3n2) virus in all se ... | 1979 | 92511 |
| preparation of projection-less particles from influenza virus and their messenger activities in prokaryotic and eukaryotic systems. | a fraction of projection-less particles was prepared from influenza a/dunedin/4/73 and a/victoria/3/75 (x-47) (h3n2) by detergent treatment and extraction into ether at 0 degrees c. the activity of this material in stimulating protein synthesis in vitro was studied and compared with that of isolated virion rna using a) an rna-dependent e. coli system, and b) a wheat germ system. in the bacterial system the purified rna had the highest template activity, while in the eukaryotic system the disrupt ... | 1978 | 343752 |
| serological evidence of continuing infection of swine in great britain with an influenza a virus (h3n2). | serum samples collected from swine and cattle in great britain at various times between july 1971 and july 1977 were examined by haemagglutination-inhibition or single radial haemolysis methods for evidence of infection with influenza a (h3n2) viruses. a small proportion of swine sera collected in each year reacted in the tests but there was no evidence of infection in cattle. the significance of the findings is discussed, with particular reference to the seasonal fluctuations in the prevalence ... | 1978 | 349075 |
| co-circulation of two influenza a (h3n2) antigenic variants detected by virus surveillance in individual communities. | from march through june 1977 a total of 31 influenza a (h3n2) viruses were isolated from students with respiratory disease who were seen at the student health service on the berkeley campus of the university of california, and 32 influenza a (h3n2) viruses were isolated from persons who participated in a city-wide febrile respiratory disease surveillance program in seattle. the antigenic specificity of the hemagglutinin was determined for each isolate by hemagglutination inhibition testing with ... | 1978 | 83107 |
| investigations on strain-specific and common antigen antihemagglutinin antibodies oriented to the influenza virus h3n2 strains a/hong kong/1/68 and a/port chalmers/1/73. | antisera raised by vaccination of chickens with the h3n2 influenza virus strains a/hong kong/1/68 and a/port/chalmers/1/73 were found to contain common antigen antibody (caa), combining with both viruses, and strain-specific antibody (ssa), combining with homologous virus only. the reaction of caa with homologous and heterologous viruses and of ssa with homologous virus was investigated by means of equilibrium filtration. caa was found to be antibody of higher quality than was ssa. the virus str ... | 1978 | 81808 |
| detection of antigenic variation in influenza virus neuraminidase by the essen-nit and the who standard procedure. | a new rapid modified micro-neuraminidase-inhibition test (essen-nit) has recently been described. this test was originally devised to facilitate large-scale screening for serum antibodies to influenza virus neuraminidase. it was shown that this test yielded results comparable to those obtained with the who standard procedure. our report presents data on the comparison between the who method and the essen-nit with respect to their capability in detecting antigenic differences in neuraminidase of ... | 1978 | 364282 |
| rapid subtyping of influenza a virus isolates by membrane fluorescence. | during the winter of 1977-1978 three influenza a virus serotypes (a/vic/3/75, a/texas/1/77 [both h3n2], and a/ussr/90/77 [h1n1]) circulated in denver, offering us the opportunity to apply fluorescent antibody techniques to the specific identification of these viruses. surface antigens of infected, unfixed primary monkey kidney cells were stained in suspension by an indirect immunofluorescence technique with anti-h3n2 and anti-h1n1 antisera. in tests of cells infected with known viruses, the memb ... | 1979 | 372228 |
| [use of peroxidase and fitc labeled antibodies for express-diagnosis of influenza]. | the evaluation of influenza antigen detection was done in comparative experiments on the same material during an epidemic of influenza due to a2/victoria (h3n2) influenza virus. cells of the nasal mucosa from 65 patients were tested at the same intervals by two methods showing no difference in the principle of the reaction: peroxidase-labeled (ip) and fitc-labeled (if) antibody. by the latter method influenza could be diagnosed in 36% of cases, by ip in 38%, by the combination of the two in 56%. ... | 1978 | 373251 |
| the measurement of haemagglutinin and matrix protein present on the surface of influenza virus infected p815 mastocytoma cells. | a thermodynamic approach has been used to measure the amount of haemagglutinin and matrix protein expressed at the surface of p815 cells infected for periods between 4.5 and 11 h with either wsn (h0n1) or jap (h2n2) strains of type a influenza virus. this involved measuring the interaction of different concentrations of labelled (fab)2 preparations of specific antibody with normal and infected cells. assuming that one molecule of (fab)2 bound to one molecule of antigen, values for the number of ... | 1979 | 107273 |
| results of virological and serological studies of three influenza a hong-kong epidemics in leningrad. | an analysis of morbidity of the population in the course of 3 influenza a/hong-kong epidemics showed a pronounced decrease in influenza affection of adult population in the last epidemic in 1971--1972. comparative studies of the diagnostic value of cfr and hit demonstrated identical sensitivity of cfr as a method of influenza diagnostics in both the epidemic and interepidemic periods. hit was suitable for the detection of influenza only in the epidemic period. in the interepidemic period, the pe ... | 1976 | 135027 |
| host antigen as the sulphated moiety of influenza virus haemagglutinin. | inorganic sulphate (35s) was incorporated into the haemagglutinin molecule of a/memphis/1/71 (h3n2) influenza virus when a keratosulphate-like host antigen was also incorporated into the glycoproteins of virus grown in the chorioallantoic membrane of the embryonated hen's egg. little or no 35s-sulphate was incorporated when this hose antigen was not present in the glycoproteins of virus grown in chick embryo kidney cells or in the chorioallantoic membrane of embryonated duck eggs. the presence o ... | 1978 | 152802 |
| failure of attenuated temperature-sensitive influenza a (h3n2) virus to induce heterologous interference in humans to parainfluenza type 1 virus. | the present investigation was undertaken to determine if a candidate live vaccine virus, influenza a/hong kong/68-ts-1 [e] (h3n2), induced heterologous interference against an interferon-sensitive, wild-type, parainfluenza type 1 challenge virus. the parainfluenza virus was administered 7 days after hong kong/68-ts-1 [e] virus infection. the clinical response, daily quantitative virus shedding, interferon production, and serum and nasal wash antibody responses were determined in an experimental ... | 1975 | 166929 |
| rhinovirus and influenza type a infections as precipitants of asthma. | specimens from 49 persons, 3 to 60 years of age, who were prone to attacks of apparently infectious asthma were cultured for viruses and bacteria during episodes of symptomatic respiratory infection from september 1972 to june 1973. seventy-one of 128 episodes (55 per cent) of symptomatic respiratory infection occurred with asthma. shedding of respiratory pathogens was associated with 43 of the 128 episodes, and 19 of the 43 etiologically defined episodes occurred with wheezing. seven of 15 rhin ... | 1976 | 174464 |
| sero-epidemiological survey on human and swine influenza a. situation at the onset of summer 1976. | a serological survey was performed to detect the presence of hi antibodies against the swine-like a/new jersey/76 (hsw1 n1) and the human a/victoria 3/75 (h3n2) virus strains in the sera of 700 subjects of different age, and of 244 swine. hi antibodies against a/new jersey/76 strain were not detected in 308 subjects younger than 31 years. they turned out to be present in 8% of the subjects from 31 to 43 years, always at low titre, and at a different titre, in 50% of the subjects from 44 to 58 ye ... | 1976 | 189788 |
| [preliminary note on the circulation of some human respiratory viruses by wild birds]. | with a view to detecting infections and carriage of human respiratory viruses in wild birds, 349 serum samples collected from 21 bird species -- sedentary ones and birds with large or limited migration areas -- were investigated. the following antigens were used: influenza virus a/hong kong 1/68 (h3n2)), a2 england 42/73 (h3n2), a2 victoria 3/75 (h3n2), a/new jersey 8/76 (hswn1), b/hong kong 5/72; parainfluenza virus type i sendai and type ii, coronavirus oc/43. an elevated incidence of antibodi ... | 1978 | 228619 |
| the effect of species and organ-specific features of tissue systems on the reactogenic and immunogenic properties of influenza virus. | the dynamics of changes in the reactogenic and immunogenic properties of influenza a/hong kong/1/68 (h3n2) virus in the course of serial passages in white mice, chick embryos, chick, cow and pig embryo kidney tissue cultures and in rat, guinea pig, chick embryo, cow embryo and pig embryo trachea organ cultures was studied. the rate of virus attenuation was found to depend not only on the species origin of tissue systems but also on their organ specificity. in rapid, 24-hour passages in chick emb ... | 1975 | 235196 |
| protective efficacy of rit 4025, a live attenuated influenza vaccine strain, and evaluation of heterotypic immunity to influenza a viruses in ferrets. | ferrets immunized with an h3n2 recombinant of a/pr/8/34 and a/scotland/840/74 (rit 4025 vaccine strain) were almost completely protected against a challenge with the homologous strain a/scotland/840/74. the protection was lower but highly significant when the challenge was performed with the heterologous a/victoria/3/75 wild strain. the protection afforded by the vaccine strain was measured by three indicators: absence of temperature rise, absence or reduction of virus shedding and absence or re ... | 1977 | 269196 |
| evolution of human influenza a viruses in nature: recombination contributes to genetic variation of h1n1 strains. | in june of 1977, a new influenza a pandemic was started by strains of the h1n1 serotype. oligonucleotide fingerprint analysis of the rna from viruses isolated during the early stage of this pandemic demonstrated that genetic variation among these 1977 strains could be attributed to sequential mutation [young, j.f., desselberger, u. & palese, p. (1979) cell, 18, 73-83]. examination of more recent strains revealed that the h1n1 variants that were isolated in the winter of 1978-1979 differed consid ... | 1979 | 293742 |
| [sorption activity of cations exchange resins of home production relative to influenza a[h3n2] virus port-chalmers strain]. | | 1979 | 459957 |
| chronic pulmonary complications of early influenza virus infection in children. | in 3 male patients, chronic pulmonary sequelae followed influenza virus infection at 5, 24, and 42 months of age. varying degrees of interstitial fibrosis, bronchial and bronchiolar erosions and metaplasia, obliterative bronchiolitis, and interstitial chronic inflammatory infiltrates were found on lung biopsy. influenza a/hong kong/68 (h3n2) virus was isolated from the lung tissue of one patient 8 weeks after the onset of illness. this is the longest persistence of infectious virus in lung tissu ... | 1977 | 303485 |
| distinct recognition of influenza virus hemagglutinin and h-2 antigens by cytotoxic thymus derived lymphocytes. | cytotoxic thymus derived (t) lymphocytes were readily detected in balb/c and c3h mice during infection with influenza a (h0n1, h3n2, heq1neq1) and b viruses. t cell mediated lysis was specific for h-2 compatible target cells infected with the same strain of virus used to immunize the mice. the viral specificity was found to be related to the hemagglutinin antigen by the use of parent strains (h3n2 and heqneq) and their recombinant viruses which included the antigenic hybrids for hemagglutinin an ... | 1977 | 304819 |
| comparative studies of wild-type and cold-mutant (temperature-sensitive) influenza viruses: nonrandom reassortment of genes during preparation of live virus vaccine candidates by recombination at 25 degrees between recent h3n2 and h1n1 epidemic strains and cold-adapted a/an arbor/6/60. | | 1979 | 473592 |
| investigation of recombinants of human influenza and fowl plague viruses. | recombinants of human influenza type a viruses, a/krasnodar/101/1959 (h2n2) or a/habarovsk/15/1976 (h3n2), and fowl plague virus (fpv), strain weybridge (hav1neq1) were obtained. the genome of the recombinant obtained by recombination of influenza a/habarovsk/15/1976 virus and fpv contained the genes 4 (ha) and 6 (na) derived from the influenza a/habarovsk virus and all the other genes [1, 2, 3, 5 (np), 7 (m), 8 (ns)] from fpv. the genome of the recombinant of a/krasnodar/101/1959 virus and fpv ... | 1979 | 479841 |
| [sorbtion of influenza virus a/port chalmers/1/73 (h3n2) on soviet-produced anionites]. | | 1979 | 481270 |
| [protective action of remantadine during an influenza outbreak caused by virus a (h1n1) in december 1977]. | the protective effect of remantadin during an influenza outbreak in december 1977 caused by a (h1n1) virus was studied. a prophylactic administration of remantadin decreased influenza and ard incidence by 1.5-fold. a more significant decrease of the incidence (2.5-fold) was observed among the subjects given a combination of remantadin and influenza vaccine (h3n2) a few days before the outbreak, which was apparently due to the interferon-inducing capacity of the vaccine. | 1979 | 483772 |
| [seroepidemiological considerations on the influenza a in umbria (1978) (author's transl)]. | the authors studied the seroepidemiology of influenza virus a/victoria/3/75 (h3n2) and a/urss/90/77 (h1n1) in umbria, in 1978. the percentage of seroprotection against the subtype h3n2 results low and in such do not inhibit the diffusion of this subtype during the next winter season. the study of seroepidemiology of subtype h1n1 demonstrated that this subtype circulated in umbria in the winter 1977-78 and that the conditions exist for its circulation. | 1979 | 485586 |
| the analysis of the monoclonal immune response to influenza virus. iii. the relationship between stimulation of virus-primed precursor b cells by heterologous viruses and reactivity of secreted antibodies. | individual splenic precursor b cells from balb/c mice primed with influenza virus pr8[a/pr/8/34 (h0n1)] were stimulated in vitro in the splenic fragment culture system by homologous or various heterologous influenza viruses. the specificity of the stimulated precursor cells was determined by analysis of the antibodies secreted by the ensuing plasma cell clone in a radioimmunoassay (ria). viruses of the h2n2 and h3n2 subtypes were unable to stimulate hemagglutinin (ha)- or neuraminidase (na)-comm ... | 1978 | 305935 |
| cellular changes in lungs of mice infected with influenza virus: characterization of the cytotoxic responses. | transpleural lavage of lungs from uninfected c3h mice yielded an average of 300,000 leukocytes per mouse. this number increased eightfold within 6 days after intranasal inoculation with virulent influenza a/hong kong/68 (h3n2) virus. macrophages and lymphocytes in approximately equal numbers comprised 90% or more of the leukocytes both before and during infection. b, t, and null lymphocytes comprised, respectively, 9, 21, and 18% of the leukocytes before infection and 7, 26, and 5% by day 6. in ... | 1978 | 310424 |
| [influenza virus a/anas acute/maritime territory/730/76(h3n2) isolated from wild ducks in the maritime territory]. | a strain a/anas acuta/primorie/730/76 was isolated in the autumn of 1976 from wild pintails in the primorskiy kray, ussr, and found by the h1 and neuraminidase activity inhibition test to be antigenically related to the reference a/hong kong/1/68 strain. the cft showed the a/anas acuta/primorie/730/76 strain to contain in its hemagglutinin 3 antigenic determinants: two common with the a/hong kong/1/68 strain and one the strain-specific, lacking in the human influenza viruses of the h3n2 antigeni ... | 1979 | 506200 |
| influenza in china in 1977: recurrence of influenzavirus a subtype h1n1. | preliminary results from epidemiological and laboratory studies on the new h1n1 influenza virus show that the 7-20 years age group suffered the highest morbidity; some adults over 20 years of age were also affected. the influenza epidemic caused by the h1n1 virus was characterized by slow spread, unevenness of attack rates, and the occurrence of many mild cases and inapparent infections. at least up to the end of 1977 there was concurrent persistence and spread of both h1n1 and h3n2 viruses. the ... | 1978 | 310732 |
| small-scale trial of live-attenuated influenza vaccine (a/hong kong/68). | seventy-one men who were given live-attenuated a/hong kong/68 (h3n2) influenza vaccine during november 1973, and 34 men given placebo were examined for changes in antibody level. overall, 12 of the 71 men (17%) given the vaccine showed a fourfold rise in haemagglutination-inhibition (hi) antibody titre after 14 days. no such rises were seen in the 34 men given placebo. however, 10 of the men showing a fourfold rise were from 19 who had no detectable hi antibody to this virus before vaccination, ... | 1977 | 322827 |
| evaluation of the single radial hemolysis test for measuring hemagglutinin- and neuraminidase-specific antibodies to h3n2 influenza strains and antibodies to influenza b. | antibodies to the h3 hemagglutinin of influenza a virus could be specifically measured by single radial hemolysis (srh) when test antigens were recombinant viruses containing the relevant h3 hemagglutinin antigen and irrelevant neq1 neuraminidase of a/equine/prague/1/56 virus. antibodies to influenza b virus could also be measured by the srh technique. antibody rises to influenza a or b virus measured by srh agreed with results of hemagglutination inhibition (hi) tests for about 80% of the sera ... | 1977 | 323281 |
| an attenuated influenza virus vaccine: protection against homologous and heterologous strains of virus. | an effective influenza vaccine should be capable of providing protection against both the homologous virus strain and heterologous strains representing antigenic "drift". two attenuated vaccines were evaluated, an a/hong kong/8/68 (h3n2) and an a/england/42/72 (h3n2) strain. volunteers were immunized intranasally with either placebo or vaccine in a "double-blind" fashion in two doses, 2 weeks apart. eighty-four subjects were challenged 30-100 days after the second dose with either the homologous ... | 1977 | 342305 |
| reactogenicity and immunogenicity of parenteral monovalent influenza a/victoria/3/75 (h3n2) virus vaccine in healthy adults. | monovalent influenza a/victoria/3/75 whole-virus vaccines prepared by merck sharp and dohme (west point, pa.) and merrell-national laboratories (cincinnati, ohio) and split-virus vaccines prepared by parke, davis and company (detroit, mich.) and wyeth laboratories (philadelphia, pa.) containing 200, 400, and 800 chick cell-agglutinating units per dose were compared with a placebo in double-blind trials in which 208 adults participated. titers of hemagglutination-inhibiting antibody of greater th ... | 1977 | 342622 |
| differentiation of the haemagglutinin genes of variant influenza viruses by rna-rna hybridization. | the genetic compositions of four antigenic variants of a/memphis/1/71 (h3n2) influenza virus, which were selected by growth in the presence of monoclonal antibodies against the haemagglutinin, were compared. the results indicate that the mutant haemagglutinin genes can be differentiated by polyacrylamide gel electrophoresis of the double stranded rna hybrids formed between virion rna and transcripts isolated from infected cells. | 1979 | 521805 |
| [influenza virus neuraminidase and its role in anti-influenzal immunity]. | the direct relationship between immunogenicity of h3n2 formolvaccine and neuraminidase activity was established. a single intranasal immunization of mice with the vaccine having a titer of hemagglutinin 1:20,000-1:40,000 in 0.5 ml with active neuraminidase increased the resistance of the animals to the challenge with mouse-adapted influenza a/ussr/053/74 (h3n2) virus almost 5-fold. a vaccine with the same hemagglutinin titer but with neuraminidase inactivated by physico-chemical factors or block ... | 1979 | 524858 |
| [etiological study of the fatal cases in the period of the influenza a epidemic of 1977-1978]. | the etiology of the disease, the age structure of fatalities, the time of death were studied in 34 fatal cases in the period of influenza a (h1n1) epidemic in december 1977-february 1978 and in 33 fatal cases during influenza a/victoria/3/75 (h3n2) epidemic in january-march, 1975 (data from some autopsy offices of kiev). the results of the investigation of the etiology by immunofluorescence and the histological methods were mostly similar. the polyetiological structure of the diseases in the inf ... | 1979 | 524859 |
| responses of elderly and chronically ill subjects to bivalent influenza a/new jersey/8/76 (hsw1n1)-a/victoria/3/75 (h3n2) vaccines. | antibody responses and side effects to bivalent influenza a virus vaccines from three different manufacturers, containing 200 or 400 chick cell-agglutinating (cca) units each of a/new jersey/8/76 (hsw1n1) and a/victoria/3/75 (h3n2) antigens, were evaluated in 234 ambulatory elderly and chronically ill volunteers in a placebo-controlled, doubld-blind study. systemic reactions did not occur significantly more often among recipients of vaccine than among volunteers who received placebo. local react ... | 1977 | 342625 |
| reinfection with influenza a (h3n2) virus in young children and their families. | the frequency and consequences of reinfection with influenza a virus were studied by longitudinal observation of families for a three-year period in which two epidemics of influenza a (h3n2) occurred. seven children followed from birth were reinfected 10-25 months after their first infection. two children were reinfected by the same h3n2 virus while the others were reinfected with a closely related variant. at least five of these reinfections were accompanied by respiratory illness. reinfection ... | 1979 | 541521 |
| airway hyperreactivity and peripheral airway dysfunction in influenza a infection. | we studied 39 consecutive college students with documented nonpneumonitic influenza a/victoria/3/75/h3n2 infection to examine alterations in pulmonary mechanics and airway reactivity to cholinergic challenge, and to assess the effect of the antiviral agent amantadine on these changes. thirty-six of the 39 subjects (92 per cent) demonstrated diminished forced flow rates and decreased density-dependent forced flow rates while breathing a helium-o2 mixture as compared to an air mixture. on initial ... | 1978 | 358877 |
| detection of cells producing surface antigen-specific antibody to influenza viruses. | b cells producing antibodies to influenza virus antigens were detected and quantitated by a hemolytic plaque assay. responses of mice after primary infection and immunization with influenza viruses were measured and compared with responses after secondary immunization. the b-cell responses were specific and differentiated between a and b influenza viruses and between different subtypes of a influenza viruses. responses to closely related influenza a virus strains of the h3n2 subtype cross-reacte ... | 1978 | 363742 |
| [serologic survey of human type a influenza virus infection following 10-year periods of prevalence of h3n2 strains]. | distribution of h.i.a. against a/new jersey/8/76 (hsw1n1), a/pr/8/34 (h0n1), a/fm/1/47 (h1n1), a/japan/305/57 (h2n2) influenza virus strains was determined in 553 serum samples, previously tested for a/hong kong/1/68 virus, collected in the late summer of 1977 in milan and bari. for all variants, distinctive antibody patterns were obtained which reflect periods of prevalence of these viruses in man. so, the peak of positivity and the higher h.i.a. levels were found for a/new jersey/8/76 strain i ... | 1979 | 552822 |
| rapid diagnosis of influenza a infection by direct immunofluorescence of nasopharyngeal aspirates in adults. | the efficacy for direct immunofluorescence of a commercial conjugate for influenza a virus prepared against whole a/udorn (h3ns) virus was studied. the conjugate was specific for influenza a virus, but its sensitivity varied depending upon the strain of influenza a tested. nasopharyngeal aspirates collected from 25 patients during an outbreak of influenza were examined for viral antigen with the conjugates and inoculated onto monkey kidney (mk) cells for virus isolation. fifteen patients had iso ... | 1979 | 387816 |
| human lymphocyte cytotoxicity against target cells infected with influenza a viruses of both recent and old strains. | in vitro measurement of lymphocyte cytotoxicity (lc) reflects one aspect of human cell-mediated immunity against influenza. we studied peripheral blood lc against target cells infected with 1 of 3 strains of influenza a virus; these represent both recent and old strains. positive lc responses were obtained in 94 % of subjects. responses were significantly greater against the older strains, a/new jersey/76 (hsw1n1) and a/pr/8/34 (h0n1), than against a/england/42/72 (h3n2). lc reactivity occurred ... | 1979 | 391110 |
| comparison of sevral wild-type influenza viruses in the ferret tracheal organ culture system. | several strains of wild-type influenza a virus were studied in the ferret tracheal organ culture system. ciliary activity and viral replication were measured. ciliary activity was reduced more rapidly by a/hong kong/45/68 (h3n2) (a/hk) and a/victoria/3/75 (h3n2) (a/vic) than by a/new jersey/8/76 (hsw1n1) (a/nj), a/scotland/840/74(3hn2) (a/scot), or a/ussr/90/77 (h1n1) (a/ussr). a/hk, a/vic, and a/scot produced titers of virus higher than a/ussr or a/nj during the first three days after infection ... | 1979 | 399387 |
| the use of transportable single-radial-diffusion immunoplates in seroepidemiological studies of influenza in the gambia. the occurrence and persistence of antibody to influenza a/hong kong/68 (h3n2) virus in selected inhabitants of two rural villages. | seroepidemiological studies of influenza in the gambia were made using transportable single-radial-diffusion immunoplates containing a/hong kong/68 (h3n2) virus as antigen. the frequency and durability of antibody so detected in selected residents of two gambian villages (manduar and kafuta) are described. transportable immunoplates were found to be an effective method for the serological surveillance of influenza and to be applicable in studies in remote areas where laboratory facilities may no ... | 1977 | 408021 |
| relevance of the immunoprecipitation assay to human immunogenicity of influenza vaccines. | influenza vaccines representing each of the four u.s. manufacturers' output for the 1975-76 respiratory season were characterized clinically and assayed by immunoprecipitation. all vaccines contained 350 cca units/dose each of the a/port chalmers/1/73 (h3n2) and a/scotland/840/74 (h3n2) viruses plus 550 cca units/dose of b/hk/5/72 virus. two of the vaccines were whole virus while the other two were subunit products; one made by extraction with ethyl ether, the second by detergent treatment. the ... | 1977 | 414949 |
| antibody response to monovalent a/new jersey/8/76 influenza vaccine in pregnant women. | the decision to implement a mass immunization program with a/new jersey/8/76 (hsw1n1) influenza vaccine provided a unique opportunity to evaluate immunological responses during pregnancy. fifty-nine pregnant and 27 nonpregnant women participated in this study. influenza virus hemagglutination-inhhibition antibody titers were determined to a/new jersey/8/76 (hsw1n1), a/japan/305/57 (h2n2), and a/hong kong/8/68 (h3n2) before and after a single dose of monovalent (200 chick cell agglutination units ... | 1979 | 583151 |
| temperature-sensitive mutants of influenza a virus: evaluation of the a/victoria/75-ts-1a2 temperature-sensitive recombinant virus in seronegative adult volunteers. | an influenza a virus recombinant bearing the surface antigens of the a/victoria/3/75 (h3n2) strain and the two ts genes of the a/udorn/72-ts-1a2 virus was evaluated for attenuation, antigenicity, and protective effect in 42 doubly seronegative adult volunteers (i.e., individuals who lacked detectable serum antibodies for the hemagglutinin and neuraminidase antigens). this recombinant, which had a 37 degrees c shutoff temperature for plaque formation and ts mutations on the genes thought to code ... | 1979 | 422239 |
| cold-adapted variants of influenza a virus: evaluation in adult seronegative volunteers of a/scotland/840/74 and a/victoria/3/75 cold-adapted recombinants derived from the cold-adapted a/ann arbor/6/60 strain. | influenza a/scotland/74 (h3n2) and a/victoria/75 (h3n2) cold-adapted (ca) recombinant viruses, prepared by mating the a/ann arbor/6/60 (h2n2) ca donor virus and influenza a wild-type virus, were evaluated in adult seronegative volunteers (serum hemagglutination-inhibiting antibody titer, </=1:8) for level of attenuation, antigenicity, and genetic stability of the temperature-sensitive and ca phenotypes. at 10(7.0) to 10(7.5) 50% tissue culture infective doses the a/scotland/74 and a/victoria/75 ... | 1979 | 422240 |
| epidemiology of influenza in lower saxony during the period 1968-1978 with particular emphasis on subtypes a(h3n2) and a(h1n1) in winter 1977-78. | the influenza surveillance in lower saxony is based mainly on laboratory investigations, and especially those which involve the isolation of influenza viruses throughout the year. these investigations have provided information on the circulation of influenza viruses and of the antigenic drift during the hong kong period which resulted in many different variants. since the advent of the hong kong virus subtype, a high excess mortality was observed only in the winter of 1969-70. in most of the oth ... | 1979 | 440200 |
| influenza a and b virus infection in infants and young children during the years 1957-1976. | influenza a virus activity was demonstrated in infants and young children from metropolitan washington, dc during each of 19 successive august-july respiratory disease years, and during 17 of these years at least 2% of hospitalized respiratory disease patients yielded an influenza a or b virus and/or showed an influenza a or b serum complement-fixing (cf) antibody response. between october 1957 and july 1976, 14.3% of 860 croup patients and 5.3% of a total of 5655 hospitalized respiratory patien ... | 1979 | 443244 |
| epidemic mechanisms of type a influenza. | the antigenic varieties of influenza a virus isolated from 1968 to 1976 in a surveillance of a small, rather remote population were similar to those from england and wales as a whole, despite frequent antigenic changes during the period. household studies in the first two h3n2 influenza a epidemics found low attack rates within households, a high proportion (70%) of affected households with only one case of influenza, similar distributions of affected households in the two epidemics by the numbe ... | 1979 | 458138 |
| [analysis of the nature of virus-associated dna in the influenza virus]. | dna sequences comprising about 5% of virus rna were found to be present in nucleoids of influenza virus grown in chick embryos. dna was found in two influenza virus strains under study belonging to different antigenic groups: honi and h3n2. no dna was demonstrated in nucleoids of a paramyxovirus, newcastle disease virus, grown under analogous conditions. the virus-associated dna belongs to unique sequences of cell dna. | 1979 | 462924 |
| influenza viruses from avian and porcine sources and their possible role in the origin of human pandemic strains. | studies on influenza viruses from feral ducks trapped in canada in august 1976, gave a 26% isolation rate from cloacal samples of juvenile birds. several different influenza a viruses were isolated, some of which possessed novel hemagglutinin and/or neuraminidase antigens. influenza a viruses isolated from the rectum of feral ducks replicate in the upper respiratory tract and also in the intestinal tract of feral and domestic ducks. representative human influenza viruses of the h0n1, h3n2 and hs ... | 1977 | 604130 |