scholarly journals Reconstructing antibody dynamics to estimate the risk of influenza virus infection

2021 ◽  
Author(s):  
Tim Tsang ◽  
Ranawaka Perera ◽  
Vicky Fang ◽  
Jessica Wong ◽  
Eunice Shiu ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Bayesian Model ◽  
Influenza Virus Infection ◽  
Fold Increase ◽  
Infection Risk ◽  
Virus Infections ◽  
Younger Adults ◽  
Protection Against Infection ◽  
Antibody Dynamics

Abstract For >70 years, a 4-fold or greater rise in antibody titer has been used to confirm influenza virus infections in paired sera, despite recognition that this heuristic can lack sensitivity. Here we analyze with a novel Bayesian model a large cohort of 2,353 individuals followed for up to 5 years in Hong Kong to characterize influenza antibody dynamics and develop an algorithm to improve the identification of influenza virus infections. After infection, we estimate that hemagglutination-inhibiting (HAI) titers were boosted by 16-fold on average and subsequently decrease by 14% per year. Greater boosting in HAI titer is observed in epidemics with a circulating strain that is different from the previous epidemic. In six epidemics, the infection risks for adults were 3%-19% while the infection risks for children were 1.6-4.4 times higher than that of younger adults. Every two-fold increase in pre-epidemic HAI titer was associated with 19%-58% protection against infection. Among the 1731 infections inferred by our model, around half were missed by the 4-fold rise criteria, suggesting that this criteria underestimates infection risks by 23-70%. The sensitivity and specificity of identifying infections for our approach are 87% (95% CrI: 85%, 89%) and 98% (95% CrI: 97%, 98%) respectively, which are higher than 82% (95% CrI: 80%, 84%) and 96% (95% CrI: 96%, 97%) for using 4-fold rise criteria. Our inferential framework clarifies the contributions of age and pre-epidemic HAI titers to characterize individual infection risk and offers an improved algorithm to identify influenza virus infections.

scholarly journals Protection against Influenza Virus Infection of Mice Fed Bifidobacterium breve YIT4064

1999 ◽  
Vol 6 (2) ◽  
pp. 186-192 ◽  
Author(s):  
Hisako Yasui ◽  
Junko Kiyoshima ◽  
Tetuji Hori ◽  
Kan Shida
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Oral Administration ◽  
Lower Respiratory Tract ◽  
Influenza Virus Infection ◽  
Oral Immunization ◽  
Igg Antibodies ◽  
Virus Infections ◽  
Bifidobacterium Breve ◽  
Specific Igg

ABSTRACT Mice fed Bifidobacterium breve YIT4064 and immunized orally with influenza virus were more strongly protected against influenza virus infection of the lower respiratory tract than ones immunized with influenza virus only. The number of mice with enhanced anti-influenza virus immunoglobulin G (IgG) in serum upon oral administration of B. breve YIT4064 and oral immunization with influenza virus was significantly greater than that upon oral immunization with influenza virus only. These findings demonstrated that the oral administration of B. breve YIT4064 increased anti-influenza virus IgG antibodies in serum and protected against influenza virus infection. The oral administration of B. breve YIT4064 may enhance antigen-specific IgG against various pathogenic antigens taken orally and induce protection against various virus infections.

scholarly journals Influenza A Virus Vaccination: Immunity, Protection, and Recent Advances Toward A Universal Vaccine

Vaccines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 434 ◽  
Author(s):  
Christopher E. Lopez ◽  
Kevin L. Legge
Keyword(s):  
Immune Response ◽  
Influenza Virus ◽  
Virus Infection ◽  
Influenza A ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
Antigenic Drift ◽  
Influenza Vaccines ◽  
Virus Infections ◽  
Universal Vaccine

Influenza virus infections represent a serious public health threat and account for significant morbidity and mortality worldwide due to seasonal epidemics and periodic pandemics. Despite being an important countermeasure to combat influenza virus and being highly efficacious when matched to circulating influenza viruses, current preventative strategies of vaccination against influenza virus often provide incomplete protection due the continuous antigenic drift/shift of circulating strains of influenza virus. Prevention and control of influenza virus infection with vaccines is dependent on the host immune response induced by vaccination and the various vaccine platforms induce different components of the local and systemic immune response. This review focuses on the immune basis of current (inactivated influenza vaccines (IIV) and live attenuated influenza vaccines (LAIV)) as well as novel vaccine platforms against influenza virus. Particular emphasis will be placed on how each platform induces cross-protection against heterologous influenza viruses, as well as how this immunity compares to and contrasts from the “gold standard” of immunity generated by natural influenza virus infection.

scholarly journals Association Between the Respiratory Microbiome and Susceptibility to Influenza Virus Infection

2019 ◽  
Vol 71 (5) ◽  
pp. 1195-1203 ◽  
Author(s):  
Tim K Tsang ◽  
Kyu Han Lee ◽  
Betsy Foxman ◽  
Angel Balmaseda ◽  
Lionel Gresh ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Influenza A ◽  
Influenza Infection ◽  
Influenza Virus Infection ◽  
Fold Increase ◽  
Transmission Model ◽  
Influenza B ◽  
Household Contacts ◽  
Index Cases

Abstract Background Previous studies suggest that the nose/throat microbiome may play an important role in shaping host immunity and modifying the risk of respiratory infection. Our aim is to quantify the association between the nose/throat microbiome and susceptibility to influenza virus infection. Methods In this household transmission study, index cases with confirmed influenza virus infection and their household contacts were followed for 9–12 days to identify secondary influenza infections. Respiratory swabs were collected at enrollment to identify and quantify bacterial species via high-performance sequencing. Data were analyzed by an individual hazard-based transmission model that was adjusted for age, vaccination, and household size. Results We recruited 115 index cases with influenza A(H3N2) or B infection and 436 household contacts. We estimated that a 10-fold increase in the abundance in Streptococcus spp. and Prevotella salivae was associated with 48% (95% credible interval [CrI], 9–69%) and 25% (95% CrI, 0.5–42%) lower susceptibility to influenza A(H3N2) infection, respectively. In contrast, for influenza B infection, a 10-fold increase in the abundance in Streptococcus vestibularis and Prevotella spp. was associated with 63% (95% CrI, 17–83%) lower and 83% (95% CrI, 15–210%) higher susceptibility, respectively. Conclusions Susceptibility to influenza infection is associated with the nose/throat microbiome at the time of exposure. The effects of oligotypes on susceptibility differ between influenza A(H3N2) and B viruses. Our results suggest that microbiome may be a useful predictor of susceptibility, with the implication that microbiome could be modulated to reduce influenza infection risk, should these associations be causal.

scholarly journals Mitochondrial morphodynamics alteration induced by influenza virus infection as a new antiviral strategy

2021 ◽  
Vol 17 (2) ◽  
pp. e1009340
Author(s):  
Irene Pila-Castellanos ◽  
Diana Molino ◽  
Joe McKellar ◽  
Laetitia Lines ◽  
Juliane Da Graca ◽  
...  
Keyword(s):  
Innate Immunity ◽  
Endoplasmic Reticulum ◽  
Influenza Virus ◽  
Virus Infection ◽  
Influenza Virus Infection ◽  
Host Cells ◽  
Virus Infections ◽  
Contact Sites ◽  
Virus Trafficking ◽  
Influenza Viral Infection

Influenza virus infections are major public health threats due to their high rates of morbidity and mortality. Upon influenza virus entry, host cells experience modifications of endomembranes, including those used for virus trafficking and replication. Here we report that influenza virus infection modifies mitochondrial morphodynamics by promoting mitochondria elongation and altering endoplasmic reticulum-mitochondria tethering in host cells. Expression of the viral RNA recapitulates these modifications inside cells. Virus induced mitochondria hyper-elongation was promoted by fission associated protein DRP1 relocalization to the cytosol, enhancing a pro-fusion status. We show that altering mitochondrial hyper-fusion with Mito-C, a novel pro-fission compound, not only restores mitochondrial morphodynamics and endoplasmic reticulum-mitochondria contact sites but also dramatically reduces influenza replication. Finally, we demonstrate that the observed Mito-C antiviral property is directly connected with the innate immunity signaling RIG-I complex at mitochondria. Our data highlight the importance of a functional interchange between mitochondrial morphodynamics and innate immunity machineries in the context of influenza viral infection.

scholarly journals Avian Influenza Virus Infection Risk in Humans with Chronic Diseases

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Yaogang Zhong ◽  
Yannan Qin ◽  
Hanjie Yu ◽  
Jingmin Yu ◽  
Haoxiang Wu ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Avian Influenza ◽  
Avian Influenza Virus ◽  
Chronic Diseases ◽  
Influenza Virus Infection ◽  
Infection Risk

scholarly journals Quantifying homologous and heterologous antibody titre rises after influenza virus infection

2016 ◽  
Vol 144 (11) ◽  
pp. 2306-2316 ◽  
Author(s):  
G. FREEMAN ◽  
R. A. P. M. PERERA ◽  
E. NGAN ◽  
V. J. FANG ◽  
S. CAUCHEMEZ ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Influenza A Virus ◽  
Antibody Titre ◽  
Influenza A ◽  
Haemagglutination Inhibition ◽  
Influenza Virus Infection ◽  
Virus Infections ◽  
Influenza A H1n1 ◽  
Antibody Titres

SUMMARYMost influenza virus infections are associated with mild disease. One approach to estimate the occurrence of influenza virus infections in individuals is via repeated measurement of humoral antibody titres. We used baseline and convalescent antibody titres measured by haemagglutination inhibition (HI) and viral neutralization (VN) assays against influenza A(H1N1), A(H3N2) and B viruses to investigate the characteristics of antibody rises following virologically confirmed influenza virus infections in participants in a community-based study. Multivariate models were fitted in a Bayesian framework to characterize the distribution of changes in antibody titres following influenza A virus infections. In 122 participants with PCR-confirmed influenza A virus infection, homologous antibody titres rose by geometric means of 1·2- to 10·2-fold after infection with A(H1N1), A(H3N2) and A(H1N1)pdm09. Significant cross-reactions were observed between A(H1N1)pdm09 and seasonal A(H1N1). Antibody titre rises for some subtypes and assays varied by age, receipt of oseltamivir treatment, and recent receipt of influenza vaccination. In conclusion, we provided a quantitative description of the mean and variation in rises in influenza virus antibody titres following influenza virus infection. The multivariate patterns in boosting of antibody titres following influenza virus infection could be taken into account to improve estimates of cumulative incidence of infection in seroepidemiological studies.

scholarly journals Feasibility of real time PCR over cell culture in diagnosis of influenza virus infection: an experience of rade I viral diagnostic laboratory of developing country

2014 ◽  
Vol 2 (1) ◽  
pp. 97-102
Author(s):  
Bhawana Jain ◽  
Ajay Kr Singh ◽  
Tanushree Dangi ◽  
Anil Kr Verma ◽  
Mukesh Dwivedi ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Real Time ◽  
Developing Country ◽  
Real Time Pcr ◽  
Correct Diagnosis ◽  
Influenza Virus Infection ◽  
Virus Infections ◽  
Diagnostic Laboratory ◽  
Viral Culture

Introduction: In spite of the discovery of viral culture technology about a century ago, its application in diagnostic labs is being used since 1970s. It served as the "gold standard" for virus detection for long. In recent years, rapid, technically less challenging, sensitive and highly specific viral identification is possible by molecular tools. Hence, the purpose of this study was to analyze the importance of real time PCR over virus culture in diagnosis of Influenza virus infections, the biggest viral challenge of present India, a developing country, so that prompt and correct diagnosis can help physicians as well as the policy makers to control the virus spread. Objective: To study the feasibility of real time PCR vis a vis viral culture technique and evaluate the utility of these methods for laboratory diagnosis of Influenza virus infections. Methodology: The study was conducted in Grade I Virology Diagnostic laboratory, Dept of Microbiology, KGMU, Lucknow. We used both real time RT-PCR and viral culture methods (on MDCK cell lines) for detection of Influenza virus infection and compared the effect of transport time, cost per sample and turnaround time on both the techniques. Results & Conclusion: Real time PCR is more practical, more sensitive, quicker and cost effective. It needs less expertise and availability of reagents is better. Though viral culture proved to be highly specific and useful for wide application but the use should currently be limited to mostly research facilities. Therefore for epidemiological diagnosis purposes real time PCR detection of Influenza virus is advised.DOI: http://dx.doi.org/10.3126/ijasbt.v2i1.9860Int J Appl Sci Biotechnol, Vol 2(1): 97-102

scholarly journals Coe (Coxsackie A21) virus, para-influenza virus and other respiratory virus infections in the R.A.F., 1958–60

1962 ◽  
Vol 60 (2) ◽  
pp. 235-248 ◽  
Author(s):  
J. C. McDonald ◽  
D. L. Miller ◽  
A. J. Zuckerman ◽  
Marguerite S. Pereira ◽  
Ann Deacon ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Respiratory Virus ◽  
Influenza Virus Infection ◽  
Admission Rate ◽  
Respiratory Illness ◽  
Influenza Viruses ◽  
Influenza B ◽  
Virus Infections ◽  
Influenza Type

1. In two R.A.F. recruit stations between November 1958 and March 1959, there were 2603 admissions to Sick Quarters with respiratory illness. Throat swabs from 1129, and paired sera from 1197 were tested for certain respiratory viruses.2. From the serological results it was estimated that 19% of the admissions were associated with influenza A infection, 7% with influenza B, 26% with adenovirus, 1% with para-influenza Type 1, 1% with para-influenza Type 3 and 8% with Coe virus, but as 21% of the identified infections were multiple the proportion of illness associated with one or more of these infections was only 50%. Thirty-four per cent of the Coe virus infections and 56% of the para-influenza virus infections were multiple.3. Virus isolation test results led to a similar estimate of the frequency of adenovirus infection (23%) but to a lower estimate for Coe virus (3%) and for the para-influenza viruses, no systematic attempt was made to isolate influenza viruses. Reasons are given for thinking that most of the admissions associated with Coe virus infection in 1958, but few of those in 1959, were caused by this agent. The proportion of illnesses attributable to viruses of the para-influenza group was probably about 1%.4. The main symptoms associated with Coe virus infection were upper respiratory. Hoarseness was rather more prominent than in other infections but the height and duration of fever and the frequency of febrile symptoms were less. The few illnesses associated with para-influenza virus infection had no obvious distinguishing features.1960 survey1. Blood specimens were taken from 205 recruits on their arrival at a recruit camp in January 1960 and immediately before their departure in March; 764 men in ten operational stations were bled in January and a sample of 260 were bled again in March.2. The respiratory illness admission rate was 25% in the recruits and 4% in the trained men; 49% of the recruits showed a rise in antibody to one or more respiratory virus antigens compared with 2% in the other group. The high rate of infection in recruits was mainly due to adenovirus (36%) and Coe virus (20%).3. It was estimated that about a third of the adenovirus infections and an eighth of the Coe virus infections were responsible for illness requiring admission. There was no indication that either infection caused any appreciable number of less severe illnesses not requiring admission.4. Evidence from this survey and the earlier one suggests that the presence of neutralizing antibody to Coe virus does not prevent infection, though it appears to lower the probability of illness.

scholarly journals Effects of Heat-Killed Levilactobacillus brevis KB290 in Combination with β-Carotene on Influenza Virus Infection in Healthy Adults: A Randomized Controlled Trial

Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 3039
Author(s):  
Shohei Satomi ◽  
Naoko Waki ◽  
Chinatsu Arakawa ◽  
Kazuhiko Fujisawa ◽  
Shigenori Suzuki ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Influenza A ◽  
Controlled Trial ◽  
Winter Season ◽  
Influenza Virus Infection ◽  
Virus Infections ◽  
Double Blind ◽  
Significant Difference ◽  
Β Carotene

Influenza, a seasonal acute respiratory disease caused primarily by the influenza virus A or B, manifests with severe symptoms leading to considerable morbidity and mortality and is a major concern worldwide. Therefore, effective preventive measures against it are required. The aim of this trial was to evaluate the preventive effects of heat-killed Levilactobacillus brevis KB290 (KB290) in combination with β-carotene (βC) on influenza virus infections in healthy Japanese subjects aged between 20 and 59 y throughout the winter season. We performed a randomized, double-blind, placebo-controlled, parallel-group trial from 16 December 2019 to 8 March 2020, comparing KB290 + βC beverage with placebo beverage. The primary endpoint was the incidence of influenza based on a doctor’s certificate. The incidence of influenza was not significantly different between the two groups. However, the subgroup analysis showed a significant difference between the two groups (influenza incidence: the KB290 + βC group 1.9%, and the placebo group 3.9%) in the subgroup of subjects aged ˂40 y, but not in the subgroup of subjects aged ≥40 y. The results of this trial suggest that the combination of KB290 and βC might be a possible candidate supplement for protection against the seasonal influenza virus infection in humans aged <40 y, although further clinical studies are needed to confirm the concrete preventive effect of this combination on influenza.

Sign in / Sign up

Export Citation Format

Share Document