scholarly journals Antigenic and genetic analyses of influenza type B viruses isolated in Russia, 1987–91

1993 ◽  
Vol 111 (3) ◽  
pp. 539-546 ◽  
Author(s):  
M. L. Hemphill ◽  
P. A. Rota ◽  
V. T. Ivanova ◽  
A. N. Slepushkin ◽  
A. P. Kendal
Keyword(s):  
United States ◽  
Sequence Analysis ◽  
Influenza Season ◽  
The United States ◽  
Evolutionary Relationships ◽  
Influenza B ◽  
Type B ◽  
Antigenic Analysis ◽  
Influenza Type ◽  
Reference Strains

SummaryFour influenza type B viruses isolated in Russia during periods of relatively low (1987–8) or high (1990–1) influenza B activity were characterized antigenically using a microneutralization assay. These isolates were antigenically similar to contemporary reference strains from either of two separate lineages represented by B/Victoria/2/87 and B/Yamagata/16/88. The evolutionary relationships of the variable portion of the haemagglutinin (HA1) genes of these viruses were determined by comparison with influenza B HA1 sequences previously obtained. The Isolate B/USSR/2/87, collected during the 1987–8 influenza season, was found to be closely related to viruses on the B/Victoria/2/87 lineage that circulated during the 1988–9 influenza season in the United States. Sequence analysis of the isolates from the 1990–1 influenza season demonstrated co-circulation of viruses from both the B/Victoria/2/87 and B/Yamagata/16/88 lineages in Russia, confirming the antigenic analysis.

scholarly journals Anomalous influenza seasonality in the United States and the emergence of novel influenza B viruses

2021 ◽  
Vol 118 (5) ◽  
pp. e2012327118
Author(s):  
Rebecca K. Borchering ◽  
Christian E. Gunning ◽  
Deven V. Gokhale ◽  
K. Bodie Weedop ◽  
Arash Saeidpour ◽  
...  
Keyword(s):  
United States ◽  
Influenza A ◽  
Reproduction Number ◽  
Influenza Season ◽  
The United States ◽  
Influenza B ◽  
Relative Dynamics ◽  
2009 H1n1 ◽  
Kinetics Of ◽  
Early Activity

The 2019/2020 influenza season in the United States began earlier than any season since the 2009 H1N1 pandemic, with an increase in influenza-like illnesses observed as early as August. Also noteworthy was the numerical domination of influenza B cases early in this influenza season, in contrast to their typically later peak in the past. Here, we dissect the 2019/2020 influenza season not only with regard to its unusually early activity, but also with regard to the relative dynamics of type A and type B cases. We propose that the recent expansion of a novel influenza B/Victoria clade may be associated with this shift in the composition and kinetics of the influenza season in the United States. We use epidemiological transmission models to explore whether changes in the effective reproduction number or short-term cross-immunity between these viruses can explain the dynamics of influenza A and B seasonality. We find support for an increase in the effective reproduction number of influenza B, rather than support for cross-type immunity-driven dynamics. Our findings have clear implications for optimal vaccination strategies.

scholarly journals Reduced Influenza B–Specific Postvaccination Antibody Cross-reactivity in the B/Victoria Lineage–Predominant 2019/20 Season

2020 ◽  
Author(s):  
Hang Xie ◽  
Ruoxuan Xiang ◽  
Hamilton J Wan ◽  
Ewan P Plant ◽  
Peter Radvak ◽  
...  
Keyword(s):  
United States ◽  
Influenza Season ◽  
Geometric Mean ◽  
The United States ◽  
Cross Reactivity ◽  
Influenza B ◽  
Close Monitoring ◽  
Double Deletion ◽  
Vaccine Component ◽  
Vaccine Type

Abstract Background The influenza activity of the 2019/20 season remained high and widespread in the United States with type B viruses predominating the early season. The majority of B viruses characterized belonged to B/Victoria (B/Vic) lineage and contained a triple deletion of amino acid (aa) 162–164 in hemagglutinin (3DEL). These 3DEL viruses are antigenically distinct from B/Colorado/06/2017 (CO/06)—the B/Vic vaccine component of the 2018/19 and 2019/20 seasons representing the viruses with a double deletion of aa 162–163 in hemagglutinin (2DEL). Methods We performed molecular characterization and phylogenetic analysis of circulating B/Vic viruses. We also conducted hemagglutination inhibition (HAI) assay using archived human postvaccination sera collected from healthy subjects administered with different types of 2018/19 or 2019/20 seasonal vaccines. Their HAI cross-reactivity to representative 3DEL viruses was analyzed. Results The CO/06-specific human postvaccination sera, after being adjusted for vaccine type, had significantly reduced HAI cross-reactivity toward representative 3DEL viruses, especially the 136E+150K subgroup. The geometric mean titers against 3DEL viruses containing 136E+150K mutations were 1.6-fold lower in all populations (P = .051) and 1.9-fold lower in adults (P = .016) compared with those against the 136E+150N viruses. Conclusions Our results indicate that postvaccination antibodies induced by the B/Vic vaccine component of the 2019/20 influenza season had reduced HAI cross-reactivity toward predominant 3DEL viruses in the United States. A close monitoring of the 3DEL 136E+150K subgroup is warranted should this subgroup return and predominate the 2020/21 influenza season.

scholarly journals Reassortment and Insertion-Deletion Are Strategies for the Evolution of Influenza B Viruses in Nature

1999 ◽  
Vol 73 (9) ◽  
pp. 7343-7348 ◽  
Author(s):  
Jonathan A. McCullers ◽  
George C. Wang ◽  
Shiqin He ◽  
Robert G. Webster
Keyword(s):  
Phylogenetic Trees ◽  
The United States ◽  
Influenza Viruses ◽  
Evolutionary Relationships ◽  
Nucleotide Sequencing ◽  
Influenza B ◽  
Antigenic Analysis ◽  
The Past ◽  
Different Strains ◽  
Reassortant Viruses

ABSTRACT The evolution of influenza B viruses is poorly understood. Reassortment of influenza B viruses in nature as a means of genetic variation has not been considered to be a major contributor to their evolution. However, the current practice of assigning evolutionary relationships by antigenic analysis of the hemagglutinin of influenza B viruses would fail to detect reassortants. In this study, influenza B viruses isolated within the past 10 years from sites in the United States and China were studied by nucleotide sequencing of the hemagglutinin and neuraminidase genes and construction of phylogenetic trees to assess evolutionary relationships. A group of viruses represented by B/Houston/1/92 possess a hemagglutinin derived from a B/Yamagata/16/88-like strain and a neuraminidase derived from a B/Victoria/2/87-like strain. A second reassortment event between the hemagglutinin of a B/Yamagata/16/88-like virus closely related to the B/Beijing/184/93 strain and the neuraminidase of a B/Victoria/2/87-like strain is represented by a single virus, B/Memphis/3/93. The neuraminidase of the reassortant viruses is most closely related to that of B/Victoria/2/87-like viruses currently circulating in Nanchang, China. A pattern of insertions and deletions in the hemagglutinin and the neuraminidase of different strains of influenza B viruses is observed. Reassortment plays a role in the evolution of influenza B viruses and may necessitate a change in the methods used to assess and identify new influenza viruses.

scholarly journals Effects of Influenza Vaccination in the United States During the 2017–2018 Influenza Season

2019 ◽  
Vol 69 (11) ◽  
pp. 1845-1853 ◽  
Author(s):  
Melissa A Rolfes ◽  
Brendan Flannery ◽  
Jessie R Chung ◽  
Alissa O’Halloran ◽  
Shikha Garg ◽  
...  
Keyword(s):  
United States ◽  
Influenza Vaccine ◽  
Influenza Vaccination ◽  
Influenza A ◽  
Influenza Season ◽  
Influenza Virus Infection ◽  
The United States ◽  
Influenza B ◽  
Medical Visits ◽  
Influenza A H1n1

Abstract Background The severity of the 2017–2018 influenza season in the United States was high, with influenza A(H3N2) viruses predominating. Here, we report influenza vaccine effectiveness (VE) and estimate the number of vaccine-prevented influenza-associated illnesses, medical visits, hospitalizations, and deaths for the 2017–2018 influenza season. Methods We used national age-specific estimates of 2017–2018 influenza vaccine coverage and disease burden. We estimated VE against medically attended reverse-transcription polymerase chain reaction–confirmed influenza virus infection in the ambulatory setting using a test-negative design. We used a compartmental model to estimate numbers of influenza-associated outcomes prevented by vaccination. Results The VE against outpatient, medically attended, laboratory-confirmed influenza was 38% (95% confidence interval [CI], 31%–43%), including 22% (95% CI, 12%–31%) against influenza A(H3N2), 62% (95% CI, 50%–71%) against influenza A(H1N1)pdm09, and 50% (95% CI, 41%–57%) against influenza B. We estimated that influenza vaccination prevented 7.1 million (95% CrI, 5.4 million–9.3 million) illnesses, 3.7 million (95% CrI, 2.8 million–4.9 million) medical visits, 109 000 (95% CrI, 39 000–231 000) hospitalizations, and 8000 (95% credible interval [CrI], 1100–21 000) deaths. Vaccination prevented 10% of expected hospitalizations overall and 41% among young children (6 months–4 years). Conclusions Despite 38% VE, influenza vaccination reduced a substantial burden of influenza-associated illness, medical visits, hospitalizations, and deaths in the United States during the 2017–2018 season. Our results demonstrate the benefit of current influenza vaccination and the need for improved vaccines.

scholarly journals DNA Sequence Analysis of Regions Surrounding blaCMY-2 from Multiple Salmonella Plasmid Backbones

2004 ◽  
Vol 48 (8) ◽  
pp. 2845-2852 ◽  
Author(s):  
W. P. Giles ◽  
A. K. Benson ◽  
M. E. Olson ◽  
R. W. Hutkins ◽  
J. M. Whichard ◽  
...  
Keyword(s):  
United States ◽  
Sequence Analysis ◽  
Salmonella Enterica ◽  
Klebsiella Oxytoca ◽  
The United States ◽  
Type B ◽  
Hybridization Data ◽  
Type D ◽  
Serovar Typhimurium ◽  
Type C

ABSTRACT The emergence in the United States of resistance to expanded-spectrum cephalosporin (e.g., ceftriaxone) within the salmonellae has been associated primarily with three large (>100-kb) plasmids (designated types A, B, and C) and one 10.1-kb plasmid (type D) that carry the bla CMY-2 gene. In the present study, the distribution of these four known bla CMY-2-carrying plasmids among 35 ceftriaxone-resistant Salmonella isolates obtained from 1998 to 2001 was examined. Twenty-three of these isolates were Salmonella enterica serotype Newport, 10 were Salmonella enterica serotype Typhimurium, 1 was Salmonella enterica serotype Agona, and 1 was Salmonella enterica serotype Reading. All 23 serotype Newport isolates carried a type C plasmid, and 5, 4, and 1 serovar Typhimurium isolate carried type B, A, and C plasmids, respectively. Both the serotype Agona and serotype Reading isolates carried type A plasmids. None of the isolates carried a type D plasmid. Hybridization data suggested that plasmid types A and C were highly related replicons. DNA sequencing revealed that the region surrounding bla CMY-2 was highly conserved in all three plasmid types analyzed (types B, C, and D) and was related to a region surrounding bla CMY-5 from the Klebsiella oxytoca plasmid pTKH11. These findings are consistent with a model in which bla CMY-2 has been disseminated primarily through plasmid transfer, and not by mobilization of the gene itself, to multiple Salmonella chromosomal backbones.

Genetic variation and evolutionary relationships amongst bluetongue viruses endemic in the United States

1991 ◽  
Vol 21 (2) ◽  
pp. 91-109 ◽  
Author(s):  
H.W. Heidner ◽  
L.G. Iezzi ◽  
B.I. Osburn ◽  
N.J. MacLachlan
Keyword(s):  
United States ◽  
Genetic Variation ◽  
The United States ◽  
Evolutionary Relationships

scholarly journals The Incoming Influenza Season — China, the United Kingdom, and the United States, 2021–2022

2021 ◽  
Vol 3 (49) ◽  
pp. 1039-1045
Author(s):  
Shasha Han ◽  
◽  
Ting Zhang ◽  
Yan Lyu ◽  
Shengjie Lai ◽  
...  
Keyword(s):  
United States ◽  
United Kingdom ◽  
Influenza Season ◽  
The United States ◽  
The United Kingdom

Disease Caused by Haemophilus influenzae Type b in the Immediate Period After Homologous Immunization: Immunologic Investigation

PEDIATRICS ◽  
1990 ◽  
Vol 85 (4) ◽  
pp. 698-704
Author(s):  
Sunil K. Sood ◽  
Robert S. Daum
Keyword(s):  
United States ◽  
Haemophilus Influenzae ◽  
Capsular Polysaccharide ◽  
The United States ◽  
Invasive Disease ◽  
Haemophilus Influenzae Type ◽  
Haemophilus Influenzae Type B ◽  
Type B ◽  
Background Rate ◽  
Protein Conjugate

Several Haemophilus influenzae type b vaccines have been licensed and recommended for administration to children in the United States. These vaccines have consisted of purified polyribosylribitol-phosphate (PRP), the capsular polysaccharide of H influenzae type b,1 alone or covalently bound to one of several carrier proteins. Two of these saccharide-protein conjugate vaccines are now licensed, a polysaccharide-diphtheria toxoid conjugate (PRP-D)2 and an oligosaccharide-mutant diphtheria toxin conjugate (HbOC).3 Two others, a polysaccharide- Neisseria meningitidis outer membrane protein conjugate (PRP-OMPC)4 and a polysaccharide-tetanus toxoid conjugate (PRP-T),5 are currently in clinical trials. One concern with the use of PRP vaccine was the suggestion that the incidence of invasive disease caused by H influenzae type b in the immediate period after immunization might be increased; this idea was supported by evidence from several sources. In a case-control study of the efficacy of PRP vaccine, Black et al6 found that 4 children were hospitalized for invasive disease within 1 week of immunization, a rate of invasive disease 6.4 times greater (95% confidence interval [CI], 2.1 to 19.2) than the background rate in unvaccinated children. In Minnesota, the relative risk for invasive disease in the first week after immunization was 6.2 (95% CI, 0.6 to 45.9),7 and the results of a study conducted by the Centers for Disease Control in six areas of the United States revealed a 1.8-fold (95% CI, 0.3 to 10.2) increase in the occurrence of invasive disease caused by H influenzae type b in the first week after immunization.8 Moreover, among 16 cases of disease caused by H influenzae type b occurring within 14 days of immunization that were passively reported to the FDA,9 10 were clustered within the first 72 hours.

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