Biophysical and immunological studies on the differential effect of guanidine hydrochloride on type A and type B influenza viruses

SUMMARYGuanidine hydrochloride selectively inactivated both the biological activity and the immunogenicity of the haemagglutinin of influenza A/X-7 (H0N2). The residual neuraminidase was fully active biologically and immunologically. The reverse was observed with influenza B/ROB; with this virus the haemagglutinin was resistant, and was immunogenic; while the neuraminidase was selectively inactivated, and was not immunogenic.

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Distribution of influenza viruses in Northern Greece during 1972–1983

Journal of Hygiene ◽

10.1017/s0022172400064780 ◽

1984 ◽

Vol 93 (2) ◽

pp. 263-267 ◽

Cited By ~ 4

Author(s):

V. Kyriazopoulou-Dalaina

Keyword(s):

Time Scale ◽

Influenza A ◽

World Wide ◽

Type A ◽

Influenza Viruses ◽

Influenza B ◽

Type B ◽

Influenza A Viruses ◽

Northern Greece

SummaryObservations on the circulation of influenza viruses in Northern Greece during the winters of 1972/3 to 1982/3 are presented.Influenza A viruses were detected every winter with the exception of those of 1973/4 and 1981/2, when neither type A nor type B was isolated. The strains of type A isolated during the study period were similar to those circulating world-wide over the same time scale.Influenza B viruses were isolated only during the winters of 1972/3 and 1979/80; influenza A viruses were also circulating in the community at those times. The B strains detected were similar to those recorded world-wide during the period of study.

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Age and secular distributions of virus-proven influenza patients in successive epidemics 1961–1976 in Cirencester: Epidemiological significance discussed

Journal of Hygiene ◽

10.1017/s0022172400064548 ◽

1984 ◽

Vol 92 (3) ◽

pp. 303-336 ◽

Cited By ~ 10

Author(s):

R. E. Hope-Simpson

Keyword(s):

Influenza A ◽

Age Distribution ◽

Type A ◽

Incidence Rates ◽

Influenza Viruses ◽

High Rate ◽

Type B ◽

Practice Population ◽

Laboratory Surveillance ◽

Age Patterns

SummaryA general practice population of around 3900, under continuous clinical and laboratory surveillance, experienced 20 outbreaks of influenza between March 1960 and March 1976. Four epidemics were caused by subtype H2N2 type A viruses, seven by subtype H3N2 type A viruses and nine outbreaks by type B viruses. The age of every person proved virologically to have influenza is related to the age structure of the community and to the phase of the epidemic in which the virus-positive specimens were collected. Children 0–15 years old suffered a higher incidence rate than adults 16–90±. Pre-school children 0–4 suffered the highest rate of infection by viruses of both influenza A subtypes, whereas older schoolchildren 10–15 suffered the highest rate of type B infections. Despite these high incidence rates neither pre-school nor schoolchildren appear to have been the major disseminators of any of these influenza viruses in the community.Adults of all ages suffered a high rate of infection even into extreme old age, and the indiscriminate age distribution among adults was sustained in the successive epidemics. Such age-patterns are not those caused by a highly infectious immunizing virus surviving by means of direct transmissions from the sick, whose prompt development of the disease continues endless chains of transmissions. An alternative epidemic mechanism – whereby the virus does not spread from the sick but becomes latent in them, reactivating seasonally so that they later infect their companions – would produce age patterns similar to those recorded here for influenza patients. The suggested mechanism is illustrated by a simple conceptual model and the influenzal age patterns are discussed in relation to the recycling of influenza A subtypes.

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Safety, Immunogenicity, and Protective Efficacy of a Chimeric A/B Live Attenuated Influenza Vaccine in a Mouse Model

Microorganisms ◽

10.3390/microorganisms9020259 ◽

2021 ◽

Vol 9 (2) ◽

pp. 259

Author(s):

Ekaterina Stepanova ◽

Elena Krutikova ◽

Pei-Fong Wong ◽

Victoria Matyushenko ◽

Ekaterina Bazhenova ◽

...

Keyword(s):

T Cell ◽

Influenza Vaccine ◽

Influenza A ◽

Type A ◽

Influenza Viruses ◽

Effector Memory ◽

Influenza B Virus ◽

Influenza B ◽

Live Attenuated Influenza Vaccine ◽

B Virus

Influenza A and B viruses cause significant morbidity and mortality worldwide. Current influenza vaccines are composed of three or four strains: A/H1N1, A/H3N2, and B (Victoria and Yamagata lineages). It is of great interest if immunization against both type A and B influenza viruses can be combined in a single vaccine strain, thus reducing the cost of vaccine production and the possibility of strain interference within the multicomponent vaccine. In the current study, we developed an experimental live cold-adapted influenza intertype reassortant (influenza A and B) vaccine on the live attenuated influenza vaccine (LAIV) A/Leningrad/134/17/57 backbone. Hemagglutinin (HA) and neuraminidase (NA) functional domains were inherited from the influenza B/Brisbane/60/2008 strain, whereas their packaging signals were substituted with appropriate fragments of influenza A virus genes. The recombinant A/B virus efficiently replicated in eggs and Madin–Darby Canine Kidney (MDCK) cells under optimal conditions, temperature-sensitive phenotype was maintained, and its antigenic properties matched the influenza B parental virus. The chimeric vaccine was attenuated in mice: after intranasal immunization, viral replication was seen only in nasal turbinates but not in the lungs. Immunological studies demonstrated the induction of IgG antibody responses against the influenza A and B virus, whereas hemagglutination inhibition (HAI) and neutralizing antibodies were detected only against the influenza B virus, resulting in significant protection of immunized animals against influenza B virus challenge. IFNγ-secreting CD8 effector memory T cells (CD44+CD62L−) were detected in mouse splenocytes after stimulation with the specific influenza A peptide (NP366); however, the T-cell response was not sufficient to protect animals against infection with a high-dose mouse-adapted A/California/07/2009 (H1N1pdm09) virus, most probably due to the mismatch of key T-cell epitopes of the H1N1 virus and the LAIV backbone. Overall, generation of the chimeric A/B LAIV virus on a licensed LAIV backbone demonstrated prospects for the development of safe and efficacious vaccine candidates that afford combined protection against both type A and type B influenza viruses; however, further optimization of the T-cell epitope content within the LAIV backbone may be required.

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Chimeric Influenza A Viruses with a Functional Influenza B Virus Neuraminidase or Hemagglutinin

Journal of Virology ◽

10.1128/jvi.77.17.9116-9123.2003 ◽

2003 ◽

Vol 77 (17) ◽

pp. 9116-9123 ◽

Cited By ~ 27

Author(s):

Astrid Flandorfer ◽

Adolfo García-Sastre ◽

Christopher F. Basler ◽

Peter Palese

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Mdck Cells ◽

Cytoplasmic Tail ◽

Type A ◽

Influenza B Virus ◽

Influenza B ◽

Type B ◽

Wild Type ◽

B Virus

ABSTRACT Reassortment of influenza A and B viruses has never been observed in vivo or in vitro. Using reverse genetics techniques, we generated recombinant influenza A/WSN/33 (WSN) viruses carrying the neuraminidase (NA) of influenza B virus. Chimeric viruses expressing the full-length influenza B/Yamagata/16/88 virus NA grew to titers similar to that of wild-type influenza WSN virus. Recombinant viruses in which the cytoplasmic tail or the cytoplasmic tail and the transmembrane domain of the type B NA were replaced with those of the type A NA were impaired in tissue culture. This finding correlates with reduced NA content in virions. We also generated a recombinant influenza A virus expressing a chimeric hemagglutinin (HA) protein in which the ectodomain is derived from type B/Yamagata/16/88 virus HA, whereas both the cytoplasmic and the transmembrane domains are derived from type A/WSN virus HA. This A/B chimeric HA virus did not grow efficiently in MDCK cells. However, after serial passage we obtained a virus population that grew to titers as high as wild-type influenza A virus in MDCK cells. One amino acid change in position 545 (H545Y) was found to be responsible for the enhanced growth characteristics of the passaged virus. Taken together, we show here that the absence of reassortment between influenza viruses belonging to different A and B types is not due to spike glycoprotein incompatibility at the level of the full-length NA or of the HA ectodomain.

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Generation of Influenza A Viruses with Chimeric (Type A/B) Hemagglutinins

Journal of Virology ◽

10.1128/jvi.77.14.8031-8038.2003 ◽

2003 ◽

Vol 77 (14) ◽

pp. 8031-8038 ◽

Cited By ~ 21

Author(s):

Taisuke Horimoto ◽

Ayato Takada ◽

Kiyoko Iwatsuki-Horimoto ◽

Masato Hatta ◽

Hideo Goto ◽

...

Keyword(s):

Protein Interactions ◽

Influenza A ◽

Reverse Genetics ◽

Lethal Dose ◽

Type A ◽

Influenza Viruses ◽

Type B ◽

Wild Type ◽

Influenza A Viruses ◽

Contributing Factors

ABSTRACT To gain insight into the intertypic incompatibility between type A and B influenza viruses, we focused on the hemagglutinin (HA) gene, systematically studying the compatibility of chimeric (type A/B) HAs with a type A genetic background. An attempt to generate a reassortant containing an intact type B HA segment in a type A virus background by reverse genetics was unsuccessful despite transcription of the type B HA segment by the type A polymerase complex. Although a type A virus with a chimeric HA segment comprising the entire coding sequence of the type B HA flanked by the noncoding sequence of the type A HA was viable, it replicated only marginally. Other chimeric viruses contained type A/B HAs possessing the type A noncoding region together with either the signal peptide or transmembrane/cytoplasmic region of type A virus or both, with the remaining regions derived from the type B HA. Each of these viruses grew to median tissue culture infectious doses of more than 105 per ml, but those with more type A HA regions replicated better, suggesting protein-protein interactions or increased HA segment incorporation into virions as contributing factors in the efficient growth of this series of viruses. All of these chimeric (A/B) HA viruses were attenuated in mice compared with wild-type A or B viruses. All animals intranasally immunized with a chimeric virus survived upon challenge with a lethal dose of wild-type type B virus. These results suggest a framework for the design of a novel live vaccine virus.

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Increasing Hemagglutination Inhibition Antibodies against Two Lineages of Type B Influenza Virus in 2017-2018 Winter Season in Beijing, China

10.21203/rs.3.rs-120270/v1 ◽

2020 ◽

Author(s):

Yao Yao ◽

Lingling CHEN ◽

Dong ZHU ◽

Runqing LI ◽

Zhipeng ZHAO ◽

...

Keyword(s):

Influenza Virus ◽

Influenza A ◽

Geometric Mean ◽

Winter Season ◽

Underlying Mechanism ◽

Influenza Viruses ◽

Influenza B ◽

Type B ◽

Influenza Activity ◽

Medical Burden

Abstract Influenza virus circulates every year with lower activity than that of influenza A virus in China. During 2017 to 2018 winter season, a sharp surge of influenza activity dominated by type B/Yamagata lineage virus caused unprecedented medical burden in Beijing. The research aimed to understand the underlying mechanism for this circulation and be prepared for epidemics in the future. Sera samples collected from the patients in 2016-2017 and 2017-2018 flu seasons were tested for profiling hemagglutinin inhibition (HI) antibodies against both prevailing Victoria and Yamagata lineages of type B influenza viruses. It showed that the seroprevalence against both lineages of the virus in 2017-2018 winter was higher than that in 2016-2017, while no difference of the seroprevalence was observed between the two viruses. Meanwhile, significant elevated geometric mean titer (GMT) against both lineages of influenza B viruses was found in the specimens collected during 2017-2018 flu season than that from 2016-2017, suggesting the viruses might undergo antigenic changes. These results also suggested that lower GMT against both type B variants in 2016-2017 might serve as an immunological niche for the dominating of B/Yamagata virus in China during 2017-2018 winter season. Our findings have implication that there was a significantly elevation of HI antibodies to influenza viruses B in 2017-2018, compared in 2016-2017. On the other hand, the low level of HI antibodies to both B/Y and B/V in 2016-2017 could contribute to the severe B/Y epidemic in 2017-2018 to some extent.

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IDENTIFICATION OF INFLUENZA VIRUSES IN HUMAN AND POULTRY IN THE AREA OF LARANGAN WET MARKET SIDOARJO-EAST JAVA, INDONESIA

Indonesian Journal of Tropical and Infectious Disease ◽

10.20473/ijtid.v4i4.230 ◽

2013 ◽

Vol 4 (4) ◽

pp. 30

Author(s):

Edith Frederika ◽

Aldise Mareta ◽

Djoko Poetranto ◽

Laksmi Wulandari ◽

Retno Asih Setyoningrum ◽

...

Keyword(s):

Influenza Virus ◽

Virus Type ◽

Influenza A ◽

Type A ◽

Influenza Viruses ◽

Nasopharyngeal Swab ◽

Type B ◽

Influenza A Viruses ◽

Type C ◽

Wet Market

Background: Influenza is a viral infection that attacks the respiratory system (nose, throat, and lungs) that commonly known as “flu”. There are 3 types of influenza viruses, such as type A, type B, and type C. Influenza virus type A is the type of virus that can infect both human and animals, virus type B are normally found only in human, and Influenza virus type C can cause mild illness in human and not causing any epidemics or pandemics. Among these 3 types of influenza viruses, only influenza A viruses infect birds, particularly wild bird that are the natural host for all subtypes of influenza A virus. Generally, those wild birds do not get sick when they are infected with influenza virus, unlike chickens or ducks which may die from avian influenza. Aim: In this study, we are identifying the influenza viruses among poultry in Larangan wet market. Method: Around 500 kinds of poultry were examined from cloacal swab. Result: Those samples were restrained with symptoms of suspected H5. The people who worked as the poultry-traders intact with the animal everyday were also examined, by taking nasopharyngeal swab and blood serum. Conclusion: Identification of influenza viruses was obtained to define the type and subtype of influenza virus by PCR.

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An evaluation of the InDevR FluChip-8G insight microarray assay in characterizing influenza a viruses

Tropical Diseases Travel Medicine and Vaccines ◽

10.1186/s40794-021-00133-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Emily S. Bailey ◽

Xinye Wang ◽

Mai-juan Ma ◽

Guo-lin Wang ◽

Gregory C. Gray

Keyword(s):

Influenza A ◽

Influenza Viruses ◽

Time Range ◽

Influenza B ◽

Influenza A Viruses ◽

Laboratory Methods ◽

Duke University ◽

Multiple Viral Strains ◽

Rapid Characterization

AbstractInfluenza viruses are an important cause of disease in both humans and animals, and their detection and characterization can take weeks. In this study, we sought to compare classical virology techniques with a new rapid microarray method for the detection and characterization of a very diverse, panel of animal, environmental, and human clinical or field specimens that were molecularly positive for influenza A alone (n = 111), influenza B alone (n = 3), both viruses (n = 13), or influenza negative (n = 2) viruses. All influenza virus positive samples in this study were first subtyped by traditional laboratory methods, and later evaluated using the FluChip-8G Insight Assay (InDevR Inc. Boulder, CO) in laboratories at Duke University (USA) or at Duke Kunshan University (China). The FluChip-8G Insight multiplexed assay agreed with classical virologic techniques 59 (54.1%) of 109 influenza A-positive, 3 (100%) of the 3 influenza B-positive, 0 (0%) of 10 both influenza A- and B-positive samples, 75% of 24 environmental samples including those positive for H1, H3, H7, H9, N1, and N9 strains, and 80% of 22 avian influenza samples. It had difficulty with avian N6 types and swine H3 and N2 influenza specimens. The FluChip-8G Insight assay performed well with most human, environmental, and animal samples, but had some difficulty with samples containing multiple viral strains and with specific animal influenza strains. As classical virology methods are often iterative and can take weeks, the FluChip-8G Insight Assay rapid results (time range 8 to 12 h) offers considerable time savings. As the FluChip-8G analysis algorithm is expected to improve over time with addition of new subtypes and sample matrices, the FluChip-8G Insight Assay has considerable promise for rapid characterization of novel influenza viruses affecting humans or animals.

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Influenza: An Emerging and Re-emerging Public Health Threat in Nepal

Annals of Clinical Chemistry and Laboratory Medicine ◽

10.3126/acclm.v3i2.20737 ◽

2018 ◽

Vol 3 (2) ◽

pp. 1-2

Author(s):

Bishnu Prasad Upadhyay

Keyword(s):

Influenza Virus ◽

Influenza A ◽

Winter Season ◽

Emerging Infectious Diseases ◽

Influenza Viruses ◽

Influenza B ◽

Influenza A Viruses ◽

Influenza A H1n1 ◽

New Variant ◽

Seasonal Epidemics

Influenza virus type A and B are responsible for seasonal epidemics as well as pandemics in human. Influenza A viruses are further divided into two major groups namely, low pathogenic seasonal influenza (A/H1N1, A/H1N1 pdm09, A/H3N2) and highly pathogenic influenza virus (H5N1, H5N6, H7N9) on the basis of two surface antigens: hemagglutinin (HA) and neuraminidase (NA). Mutations, including substitutions, deletions, and insertions, are one of the most important mechanisms for producing new variant of influenza viruses. During the last 30 years; more than 50 viral threat has been evolved in South-East Asian countriesof them influenza is one of the major emerging and re-emerging infectious diseases of global concern. Similar to tropical and sub-tropical countries of Southeast Asia; circulation of A/H1N1 pdm09, A/H3N2 and influenza B has been circulating throughout the year with the peak during July-November in Nepal. However; the rate of infection transmission reach peak during the post-rain and winter season of Nepal.

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Molecular Characterization of Seasonal Influenza A and B from Hospitalized Patients in Thailand in 2018–2019

Viruses ◽

10.3390/v13060977 ◽

2021 ◽

Vol 13 (6) ◽

pp. 977

Author(s):

Kobporn Boonnak ◽

Chayasin Mansanguan ◽

Dennis Schuerch ◽

Usa Boonyuen ◽

Hatairat Lerdsamran ◽

...

Keyword(s):

Amino Acid ◽

Influenza A ◽

Seasonal Influenza ◽

Influenza Viruses ◽

Surface Proteins ◽

Antigenic Drift ◽

Influenza B ◽

Receptor Binding Site ◽

Antigenic Sites ◽

Ha Protein

Influenza viruses continue to be a major public health threat due to the possible emergence of more virulent influenza virus strains resulting from dynamic changes in virus adaptability, consequent of functional mutations and antigenic drift in surface proteins, especially hemagglutinin (HA) and neuraminidase (NA). In this study, we describe the genetic and evolutionary characteristics of H1N1, H3N2, and influenza B strains detected in severe cases of seasonal influenza in Thailand from 2018 to 2019. We genetically characterized seven A/H1N1 isolates, seven A/H3N2 isolates, and six influenza B isolates. Five of the seven A/H1N1 viruses were found to belong to clade 6B.1 and were antigenically similar to A/Switzerland/3330/2017 (H1N1), whereas two isolates belonged to clade 6B.1A1 and clustered with A/Brisbane/02/2018 (H1N1). Interestingly, we observed additional mutations at antigenic sites (S91R, S181T, T202I) as well as a unique mutation at a receptor binding site (S200P). Three-dimensional (3D) protein structure analysis of hemagglutinin protein reveals that this unique mutation may lead to the altered binding of the HA protein to a sialic acid receptor. A/H3N2 isolates were found to belong to clade 3C.2a2 and 3C.2a1b, clustering with A/Switzerland/8060/2017 (H3N2) and A/South Australia/34/2019 (H3N2), respectively. Amino acid sequence analysis revealed 10 mutations at antigenic sites including T144A/I, T151K, Q213R, S214P, T176K, D69N, Q277R, N137K, N187K, and E78K/G. All influenza B isolates in this study belong to the Victoria lineage. Five out of six isolates belong to clade 1A3-DEL, which relate closely to B/Washington/02/2009, with one isolate lacking the three amino acid deletion on the HA segment at position K162, N163, and D164. In comparison to the B/Colorado/06/2017, which is the representative of influenza B Victoria lineage vaccine strain, these substitutions include G129D, G133R, K136E, and V180R for HA protein. Importantly, the susceptibility to oseltamivir of influenza B isolates, but not A/H1N1 and A/H3N2 isolates, were reduced as assessed by the phenotypic assay. This study demonstrates the importance of monitoring genetic variation in influenza viruses regarding how acquired mutations could be associated with an improved adaptability for efficient transmission.

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