Prevention Of Influenza Virus Infection Research Articles

High-dose trivalent influenza vaccine. Efficacy and effectiveness

RESUMENLa gripe estacional es un importante problema de salud pública, particularmente en las personas mayores. La vacuna antigripal es la forma más efectiva de prevenir la infección por el virus de la gripe y sus complicaciones, pero debido al fenómeno de inmunosenescencia asociado a la edad, las personas mayores no responden eficientemente a la inmunización. En 2009 se aprobó en EE. UU. una vacuna antigripal trivalente de alta dosis (IIV3-HD), con una concentración cuatro veces mayor de antígeno que la vacuna estándar, para la inmunización de personas ≥ 65 años. En numerosos ensayos clínicos llevados a cabo en diferentes temporadas, y utilizando diferentes metodologías, se ha demostrado que la vacuna IIV3-HD es, además de segura, más inmunogénica y más efectiva que la vacuna de dosis estándar previniendo la gripe y sus complicaciones en personas mayores. En este trabajo se hace una revisión de la evidencia científica disponible sobre la eficacia y efectividad de la vacuna antigripal de alta dosis en personas ≥ 65 años, incluyendo información de ensayos clínicos aleatorizados, estudios observacionales de práctica clínica real y revisiones sistemáticas y meta-análisis.

COVID-19 War, Human Microbiota Function

COVID-19 War, Human Microbiota Function

Fusion protein (M2e-HA2-NP) adjuvanted with γ-PGA/Alum induce the cross-reactivity against heterologous influenza A viruses

Abstract The epidemic and pandemic influenza viruses result in substantial morbidity and mortality in humans. Vaccination is the most effective way to prevent influenza virus infection. In this study, we cloned the conserved regions of influenza A virus, extracellular domain of matrix protein 2 (M2e), hemagglutinin 2 (HA2) and nucleoprotein (NP). Then, we generated fusion (M2e-HA2-NP) protein as a universal vaccine antigen candidate. γ-PGA/Alum (PA) was used as an adjuvant to enhance the efficacy of fusion protein. In mice challenged with influenza viruses, fusion protein (15 μg) provided 100% protection against A/Puerto Rico/8/1934 (H1N1; PR8) or A/California/04/09 (pH1N1; CA04) and 80% protection against H3N2 (a reassortant virus carrying HA and NA genes of A/Hong Kong/1/68). In dose-sparing effect experiments, low dose (1 or 5 μg) of fusion protein with PA provided the same protection comparable to 15 μg of fusion protein against H1N1, pH1N1 and H3N2. Humoral and cellular immunities against heterologous influenza viruses were significantly enhanced in mice vaccinated with fusion protein mixed with PA compared with alum-adjuvanted fusion protein. Taken together, the fusion protein adjuvanted with PA may be a good vaccine candidate showing heterosubtypic cross-reactivity.

Prevention of influenza virus infection and transmission by intranasal administration of a porous maltodextrin nanoparticle-formulated vaccine.

Influenza vaccines administered intramuscularly exhibit poor mucosal immune responses in the respiratory tract which is the prime site of the infection. Intranasal vaccination is a potential route for vaccine delivery which has been demonstrated effective in inducing protective immune responses in both systemic and mucosal compartments. For this purpose, nanoparticles have been used as antigen delivery systems to improve antigen capture by immune cells. In this paper we demonstrate efficient delivery of viral antigens to airway epithelial cells, macrophages and dendritic cells, using polysaccharide nanoparticles (NPL), leading to a strong protection against influenza virus infection. A formulation combining split Udorn virus antigens with NPL and the mucosal protein adjuvant CTA1-DD was administered intranasally and resulted in an enhanced specific humoral immune response. Furthermore, NPL carrying split Udorn, with or without CTA1-DD, inhibited virus transmission from infected to uninfected naive mice. These results demonstrate that an intranasal delivery system combining NPL, mucosal adjuvant CTA1-DD and split virus antigens confers robust protection against influenza infection and inhibits virus transmission.

Mixed polysaccharides derived from Shiitake mushroom, Poriacocos, Ginger, and Tangerine peel enhanced protective immune responses in mice induced by inactivated influenza vaccine

Influenza viruses are responsible for severe respiratory tract infections of individuals and may cause pandemics with a high risk of mortality and morbidity. Although vaccination is a primary means for prevention of influenza virus infections, poor vaccine performance or inadequate immune responses limits the efficacy of current vaccines and raises question regarding whether a better correlates of protection procedures should be performed. Here, we want to evaluate whether mixed polysaccharides (MPs) derived from shiitake mushroom, poriacocos, ginger, and dried tangerine peel could promote the immune response of inactivated influenza vaccine. Firstly, MPs were given to mice each day and for a total of 30 days, during which two immunizations were performed on mice on days 14 and 21. The results showed that serum total IgG and IgG2a levels were increased in MPs-treated mice on day 30. Following A/WSN/33 (H1N1) virus challenge, we found that MPs pretreatment in mice could increase mice weight gain and attenuate their clinical symptoms. Additional protective factors were also observed including prevention of excessive lung inflammation, promotion of CD19+ and CD278+ cell proportions in lung, elimination of virus in lung, and elevation of IFN-γ levels in serum. The current study demonstrate that MPs from shiitake mushroom, poriacocos, ginger, and dried tangerine peel could promote the immune efficacy and alleviate lung inflammation in mice with vaccines against H1N1 virus infection by activating both humoral and cellular immunity.

N-Linked Glycans and K147 Residue on Hemagglutinin Synergize To Elicit Broadly Reactive H1N1 Influenza Virus Antibodies.

Vaccination is the most effective way to prevent influenza virus infections. However, the diversity of antigenically distinct isolates is a challenge for vaccine development. In order to overcome the antigenic variability and improve the protective efficacy of influenza vaccines, our research group has pioneered the development of computationally optimized broadly reactive antigens (COBRA) for hemagglutinin (HA). Two candidate COBRA HA vaccines, P1 and X6, elicited antibodies with differential patterns of hemagglutination inhibition (HAI) activity against a panel of H1N1 influenza viruses. In order to better understand how these HA antigens elicit broadly reactive immune responses, epitopes in the Cb, Sa, or Sb antigenic sites of seasonal-like and pandemic-like wild-type or COBRA HA antigens were exchanged with homologous regions in the COBRA HA proteins to determine which regions and residues were responsible for the elicited antibody profile. Mice were vaccinated with virus-like particles (VLPs) expressing one of the 12 modified HA antigens (designated V1 to V12), COBRA HA antigens, or wild-type HA antigens. The elicited antisera was assessed for hemagglutination inhibition activity against a panel of historical seasonal-like and pandemic-like H1N1 influenza viruses. Primarily, the pattern of glycosylation sites and residues in the Sa antigenic region, around the receptor binding site (RBS), served as signatures for the elicitation of broadly reactive antibodies by these HA immunogens. Mice were vaccinated with VLPs expressing HA antigens that lacked a glycosylation site at residue 144 and a deleted lysine at position 147 residue were more effective at protecting against morbidity and mortality following infection with pandemic-like and seasonal-like H1N1 influenza viruses.IMPORTANCE There is a great need to develop broadly reactive or universal vaccines against influenza viruses. Advanced, next-generation hemagglutinin (HA) head-based vaccines that elicit protective antibodies against H1N1 influenza viruses have been developed. This study focused on understanding the specific amino acids around the receptor binding site (RBS) that were important in elicitation of these broadly reactive antibodies. Specific glycan sites and amino acids located at the tip of the HA molecule enhanced the elicitation of these broadly reactive antibodies. A better understanding of the HA structures around the RBS will lead to more effective HA immunogens.

Technical guidelines for seasonal influenza vaccination in China (2019-2020)

Influenza virus infection is a respiratory infectious disease. The World Health Organization (WHO) estimated that seasonal influenza epidemics have caused an annual 3 to 5 million severe cases, and 290 000 to 650 000 deaths globally. Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and complications from infection. Currently, China has licensed trivalent inactivated influenza vaccine (IIV3) and quadrivalent inactivated influenza vaccine (IIV4). In 2018, the Chinese Center for Disease Control and Prevention issued the "Technical Guidelines for Seasonal Influenza Vaccination in China (2018-2019)" ( "Guide 2018" for short). To strengthen the technical guidance for prevention and control of influenza and operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC) Influenza Vaccination Technical Working Group (TWG), updated the 2018 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2019-2020)" . The main updates in this version include the following: First, new research evidences especially studies of China, including disease burden, effectiveness, Vaccine-avoidable disease burden, vaccine safety monitoring, and cost-effectiveness and cost-benefit. Second, policies and measures for influenza prevention and control issued by National Health Commission (PRC) in the past year. Thirdly, new type seasonal influenza vaccine licensed and issued in 2019-2020 in China. Fourth, northern hemisphere influenza vaccination composition for the 2019-2020 season which included trivalent and quadrivalent influenza vaccine. The recommendations described in this report include the following: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for one influenza vaccine product over another for persons for whom more than one licensed, recommended, and appropriate product is available. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-59 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to become pregnant during the influenza season. Children aged 6 months through 8 years require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in 2018-2019 influenza season or a prior season, 1 dose is recommended. People more than 8 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. For the people unable to be vaccinated before the end of October, influenza vaccination will continue to be offered for the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for use by staff members of the Centers for Disease Control and Prevention at all levels who work on influenza control and prevention, PoVs staff members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and staff members of maternity and child care institutions at all levels. These guidelines will be updated periodically as new evidence becomes available.

Surveillance on the Immune Effectiveness of Quadrivalent andTrivalent Split Influenza Vaccines - Shenzhen Cityand Changzhou City, China, 2018-2019.

What is already known about this topic? Vaccinations are the most effective way to prevent influenza virus infections and severe outcomes. Influenza vaccine effectiveness can vary by seasons. What is added by this report? This report monitors the antibody level among the population over time after administration of the quadrivalent or trivalent split influenza vaccine. What are the implications for public health practice? Real-time monitoring of serum antibody changes after vaccination provides important data for the development of reasonable and effective strategies for influenza prevention and control.

Effectiveness of seasonal inactivated influenza vaccination in Japanese schoolchildren: an epidemiologic study at the community level

ABSTRACTInfluenza vaccination is the most effective method for preventing influenza virus infection. The incidence of influenza is higher in schoolchildren than other age groups. This study evaluated the effectiveness of seasonal inactivated influenza vaccination (IIV) in a community population of schoolchildren during two seasons. This study was a cross-sectional survey of public schoolchildren based on data collected in the 2012/2013 and 2014/2015 seasons. The questionnaire was distributed to all public schoolchildren of target grade in a survey area, and 7945 respondents were included in the analysis. The vaccination status and influenza onset were defined based on the self-reported questionnaire by parents or guardians. Generalized linear mixed models were used to adjust clustering within schools and individual covariates and calculate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between vaccination status and influenza onset. The influenza incidence was higher in the 2015 than the 2013 survey (25% versus 17%), although the vaccination rates were comparable between the two seasons. Receiving one- or two-dose vaccination was more protective against influenza than non-vaccination in both the 2013 (OR, 0.77; 95%CI, 0.65–0.92) and 2015 (OR, 0.88; 95%CI, 0.75–1.02) surveys. Full vaccination was also more protective in both the 2013 (OR, 0.75; 95%CI, 0.62–0.89) and 2015 (OR, 0.86; 95%CI, 0.74–1.00) surveys. Seasonal IIV was protective against influenza for Japanese schoolchildren in a community-based real-world setting. The difference in clinical effectiveness of IIV between the two seasons was likely due to the antigenic mismatch between the circulating and vaccine strains.

Current and Novel Approaches in Influenza Management.

Influenza is a disease that poses a significant health burden worldwide. Vaccination is the best way to prevent influenza virus infections. However, conventional vaccines are only effective for a short period of time due to the propensity of influenza viruses to undergo antigenic drift and antigenic shift. The efficacy of these vaccines is uncertain from year-to-year due to potential mismatch between the circulating viruses and vaccine strains, and mutations arising due to egg adaptation. Subsequently, the inability to store these vaccines long-term and vaccine shortages are challenges that need to be overcome. Conventional vaccines also have variable efficacies for certain populations, including the young, old, and immunocompromised. This warrants for diverse efficacious vaccine developmental approaches, involving both active and passive immunization. As opposed to active immunization platforms (requiring the use of whole or portions of pathogens as vaccines), the rapidly developing passive immunization involves administration of either pathogen-specific or broadly acting antibodies against a kind or class of pathogens as a treatment to corresponding acute infection. Several antibodies with broadly acting capacities have been discovered that may serve as means to suppress influenza viral infection and allow the process of natural immunity to engage opsonized pathogens whilst boosting immune system by antibody-dependent mechanisms that bridge the innate and adaptive arms. By that; passive immunotherapeutics approach assumes a robust tool that could aid control of influenza viruses. In this review, we comment on some improvements in influenza management and promising vaccine development platforms with an emphasis on the protective capacity of passive immunotherapeutics especially when coupled with the use of antivirals in the management of influenza infection.

Evaluation of the influenza vaccine effectiveness among children aged 6 to 72 months based on the test-negative case control study design

Objective: To assess the effectiveness of seasonal influenza vaccine among children aged 6 to 72 months. Methods: The test-negative case control study was conducted based on available surveillance data which was from China Influenza Surveillance Information system (CSIS). From October 2016 to April 2017 and from October 2017 to April 2018,1 161 cases aged 6-72 months with influenza-like illness in Yongkang and Yiwu city, were selected as the study subjects, and the cases with influenza test-positive were selected as the case group (403 cases). Test-negative subjects were selected as control group (758 cases). The etiology and immunization data of the subjects were obtained from CSIS and Immune Information and Management System (IIMS) respectively. Vaccine effectiveness was estimated using multivariate logistic regression model,and the mixed effects of non-randomized control in TNCC study were equalized by using the propensity score (PS) method in the statistical analysis. Results: The age of the subjects was (2.44±1.60) years,and there were 681 boys (58.66%). The age of case group was (2.62±1.58) years, and there were 246 boys (61.04%). The case group was including of 237 cases (58.81%) of influenza A (H3N2), 92 cases (22.83%) of influenza A (H1N1) pmd09, 62 cases (15.38%) of influenza B(Victoria) lineage, 11 cases (2.73%) of influenza B (Yamagata) lineage and one case (0.25%) co-infection of influenza [A(H(3)N(2))+B (Victoria)]. The mean age of the control group was (2.35±1.61) years,and there were 435 boys (57.39%). Overall vaccine effectiveness (VE) against all type influenza for two seasons combined was 58% (95%CI: 31%-74%). An analysis by age groups showed 68% (95%CI:41%-82%) of the VE estimate among children aged 36-72 months while it was 28%(95%CI:-80%-71%)of the VE estimate among children aged 6-35 months. The VE estimate value was 54% (95%CI:16%-75%) against all type influenza and 65% (95%CI:24%-83%) against influenza A (H(3)N(2)) during the 2016-2017 season. During the 2017-2018 season, the VE estimate value was 69% (95%CI:18%-88%) against all type influenza. Conclusion: Influenza vaccine is effective in preventing influenza virus infection during the flu season,especially the effect among children aged 36-72 months is higher compared to that among children aged 6-35 months.

The complex of poly-γ-glutamic acid and aluminum salts ameliorates the reduced efficacy of the influenza H1N1 vaccine in aged mice

Abstract Influenza is a highly contagious respiratory disease caused by the influenza A viruses and results in public health threat like seasonal epidemics and sporadic pandemics. Although vaccination is considered to be one of the most effective strategy for preventing the disease, the low efficacy of the influenza vaccine has been reported in the elderly. Here, we examined that the aging-related reduced efficacy of the influenza vaccine can be ameliorated by the complex of poly-γ-glutamic acid (γ-PGA) and alum (PGA/Alum), a novel adjuvant capable of inducing both humoral and cellular immune responses, using an aged mouse model. PGA/Alum induced activation of dendritic cells from aged mice, accompanied with increase of both expression of co-stimulatory molecules and production of pro-inflammatory cytokines. In addition, PGA/Alum enhanced the protective efficacy of pandemic influenza H1N1 (pH1N1) vaccine in aged mice, with earlier virus clearance after A/California/4/2009 (pH1N1) viral challenge, increased hemagglutination-inhibition titers, activity of cytotoxic T lymphocytes, and generation of multifunctional T lymphocytes. Taken together, these results suggest that PGA/Alum is a potent vaccine adjuvant that could improve the reduced vaccine efficacy of aging, thereby leading to prevention of influenza virus infection in the immune compromised populations.

Indirect protection from vaccinating children against influenza in households

Vaccination is an important intervention to prevent influenza virus infection, but indirect protection of household members of vaccinees is not fully known. Here, we analyze a cluster household randomized controlled trial, with one child in each household randomized to receive influenza vaccine or placebo, for an influenza B epidemic in Hong Kong. We apply statistical models to estimate household transmission dynamics and quantify the direct and indirect protection of vaccination. Direct vaccine efficacy was 71%. The infection probability of unvaccinated household members in vaccinated households was only 5% lower than in control households, because only 10% of infections are attributed to household transmission. Even when that proportion rises to 30% and all children are vaccinated, we predict that the infection probability for unvaccinated household members would only be reduced by 20%. This suggests that benefits of individual vaccination remain important even when other household members are vaccinated.

Effectiveness of hand hygiene practices in preventing influenza virus infection in the community setting: A systematic review.

BackgroundHand hygiene is known to be an effective infection prevention and control measure in health care settings. However, the effectiveness of hand hygiene practices in preventing influenza infection and transmission in the community setting is not clear.ObjectiveTo identify, review and synthesize available evidence on the effectiveness of hand hygiene in preventing laboratory-confirmed or possible influenza infection and transmission in the community setting.MethodsA systematic review protocol was established prior to conducting the review. Three electronic databases (MEDLINE, Embase and the Cochrane Library) were searched to identify relevant studies. Two reviewers independently screened the titles, abstracts and full-texts of studies retrieved from the database searches for potential eligibility. Data extraction and quality assessment of included studies were performed by a single reviewer and validated by a second reviewer. Included studies were synthesized and analyzed narratively.ResultsA total of 16 studies were included for review. Studies were of low methodological quality and there was high variability in study design, setting, context and outcome measures. Nine studies evaluated the effectiveness of hand hygiene interventions or practices in preventing laboratory-confirmed or possible influenza infection in the community setting; six studies showed a significant difference, three studies did not. Seven studies assessed the effectiveness of hand hygiene practices in preventing laboratory-confirmed or possible influenza transmission in the community setting; two studies found a significant difference and five studies did not.ConclusionThe effectiveness of hand hygiene against influenza virus infection and transmission in the community setting is difficult to determine based on the available evidence. In light of its proven effectiveness in other settings, there is no compelling evidence to stop using good hand hygiene practice to reduce the risk of influenza infection and transmission in the community setting.

Effectiveness of hand hygiene practices in preventing influenza virus infection in the community setting: A systematic review

Effectiveness of hand hygiene practices in preventing influenza virus infection in the community setting: A systematic review

Technical guidelines for seasonal influenza vaccination in China, 2018-2019

Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and its complications. Currently, China has licensed trivalent (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. In most parts of China, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients need to pay for it. To strengthen the technical guidance for prevention and control of influenza and the operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC), Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" , based on most recent existing scientific evidences. The main updates include: epidemiology and disease burden of influenza, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, and, IIV3 and IIV4 vaccines'major immune responses, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The recommendations include: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for any influenza vaccine product for persons who can accept ≥1 licensed, recommended, and appropriate products. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-60 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to pregnant during the influenza season. Children aged 6 months to 8 years old require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in previous influenza season, 1 dose is recommended. People ≥ 9 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. Influenza vaccination should continue to be available for those unable to be vaccinated before the end of October during the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for CDC members who are working on influenza control and prevention, PoVs members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and members of maternity and child care institutions at all levels.

The Antihistamine Drugs Carbinoxamine Maleate and Chlorpheniramine Maleate Exhibit Potent Antiviral Activity Against a Broad Spectrum of Influenza Viruses.

Influenza A viruses (IAV) comprise some of the most common infectious pathogens in humans, and they cause significant mortality and morbidity in immunocompromised people as well as children and the elderly. After screening an FDA-approved drug library containing 1280 compounds by cytopathic effect (CPE) reduction assay using the Cell Counting Kit-8, we found two antihistamines, carbinoxamine maleate (CAM) and S-(+)-chlorpheniramine maleate (SCM) with potent antiviral activity against A/Shanghai/4664T/2013(H7N9) infection with IC50 (half-maximal inhibitory concentration) of 3.56 and 11.84 μM, respectively. Further studies showed that CAM and SCM could also inhibit infection by other influenza A viruses, including A/Shanghai/37T/2009(H1N1), A/Puerto Rico/8/1934(H1N1), A/Guizhou/54/1989(H3N2), and one influenza B virus, B/Shanghai/2017(BY). Mice were challenged intranasally with A/H7N9/4664T/2013 (H7N9) virus and intraperitoneally injected with CAM (10 mg/kg per day) or SCM (1 mg/kg per day) for 5 days. CAM or SCM (10 mg/kg per day) were fully protected against challenge with A/Shanghai/4664T/2013(H7N9). The results from mechanistic studies indicate that both could inhibit influenza virus infection by blocking viral entry into the target cell, the early stage of virus life cycle. However, CAM and SCM neither blocked virus attachment, characteristic of HA activity, nor virus release, characteristic of NA activity. Such data suggest that these two compounds may interfere with the endocytosis process. Thus, we have identified two FDA-approved antihistamine drugs, CAM and SCM, which can be repurposed for inhibiting infection by divergent influenza A strains and one influenza B strain with potential to be used for treatment and prevention of influenza virus infection.

Technical guidelines for seasonal influenza vaccination in China (2018-2019)

Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and complications from infection. Currently, China has licensed trivalent inactivated influenza vaccine (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. Except for a few major cities, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients must pay for it. To strengthen the technical guidance for prevention and control of influenza and operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC) Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" . The main updates in this version include: epidemiology, disease burden, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, IIV3 and IIV4 immune response, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The influenza vaccine TWG provided the recommendations for influenza vaccination for the 2018-2019 influenza season based on existing scientific evidence. The recommendations described in this report include the following: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for one influenza vaccine product over another for persons for whom more than one licensed, recommended, and appropriate product is available. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-59 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to become pregnant during the influenza season. Children aged 6 months through 8 years require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in 2017-2018 influenza season or a prior season, 1 dose is recommended. People more than 8 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. For the people unable to be vaccinated before the end of October, influenza vaccination will continue to be offered for the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for use by staff members of the Centers for Disease Control and Prevention at all levels who work on influenza control and prevention, PoVs staff members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and staff members of maternity and child care institutions at all levels.

Influenza vaccine effectiveness in reducing severe outcomes over six influenza seasons, a case-case analysis, Spain, 2010/11 to 2015/16.

IntroductionWhen influenza vaccination is ineffective in preventing influenza virus infection, it may still reduce the severity of influenza-associated disease. Here, we estimate the effect of influenza vaccination in preventing severe outcomes e.g. intensive care unit (ICU) admission and death, even though it did not prevent influenza virus infection and subsequent hospitalisation.MethodsAn observational case–case epidemiological study was carried out in 12 sentinel hospitals in Catalonia (Spain) over six influenza seasons 2010/11–2015/16. Cases were individuals with severe laboratory-confirmed influenza virus infection and aged 18 years and older. For each reported case we collected demographic, virological and clinical characteristics. Logistic regression was used to estimate the crude, adjusted odd ratios (aOR) and 95% confidence intervals (CI).ResultsOf 1,727 hospitalised patients included in the study, 799 were female (46.7%), 591 (34.2%) were admitted to the ICU and 223 (12.9%) died. Influenza vaccination uptake was lower in cases that required ICU admission or died (21.2% vs 29.7%, p < 0.001). The adjusted influenza vaccination effectiveness in preventing ICU admission or death was 23% (95% CI: 1 to 40). In an analysis restricted to sex, age group and antiviral treatment, influenza vaccination had a positive effect on disease severity in all age groups and categories.ConclusionsWe found that influenza vaccination reduced the severity of disease even in cases where it did not prevent infection and influenza-associated hospitalisation. Therefore, increased vaccination uptake may reduce complications, ICU admission and death.

Inactivation of human and avian influenza viruses by potassium oleate of natural soap component through exothermic interaction.

An influenza epidemic is still a problem despite the development of vaccines and anti-influenza drugs. Preventive measures such as handwashing are fundamental and important for counteracting influenza virus infection. In this study, we clarified the anti-influenza virus effects of surfactants, which are the main components of hand soaps for hand washing: potassium oleate (C18:1), sodium laureth sulfate (LES) and sodium lauryl sulfate (SDS). For a human influenza virus strain (H3N2), C18:1 reduced the infectivity by 4 logs or more, whereas LES and SDS reduced the infectivity by 1 log or less. Similar results were obtained when an avian influenza virus strain (H5N3) was used. The interaction between the surfactant and virus was then investigated by isothermal titration calorimetry. The LES-virus system showed a positive value of enthalpy changes (ΔH), meaning an exothermic interaction that indicated a hydrophobic interaction. In contrast, both the C18:1-virus system and the SDS-virus system showed negative values of ΔH, meaning an endothermic interaction that indicated an electrical interaction. The ΔH value of the C18:1-virus system was much higher than that of the SDS-virus system. A mixture of C18:1 and HA proteins similarly showed negative values of ΔH. These results indicate that influenza virus inactivation by a hydrophobic interaction of a surfactant with the viral envelope is insufficient to prevent infection, whereas inactivation by an electrical interaction of a surfactant with HA proteins is sufficient to prevent influenza virus infection.