OBJECTIVETo estimate the effectiveness of inactivated influenza vaccine in elderly population.

METHODSAn quasi-experimental study was used. 590 elderly people who volunteered to receive the influenza vaccine were served as vaccine group, while 602 persons who did not want to receive the inoculation but could match the vaccine group were served as controls. One baseline and three follow-up surveys were carried out.

RESULTSThe protective rates of influenza like ill (ILI) as 52.38%, 36.84% and 37.89% with the decreasing rates of visits to ILI clinic as 45.16%, 50.54% and 50.54% were found after 1 month, 3 month and 6 month of inoculation of influenza vaccine; The protective rates of common cold, other respiratory tract or chronic disease were 49.54%, 64.54%, and 38.82%, respectively. The benefit-cost ratio was 4.98:1 in elderly population.

CONCLUSIONInfluenza vaccination could decrease ILI incidence and recurrence rates of related chronic diseases on elderly population to provide better economic benefits for the elderly.

Aged ; China ; epidemiology ; Cost-Benefit Analysis ; Female ; Humans ; Influenza Vaccines ; economics ; immunology ; Influenza, Human ; epidemiology ; prevention & control ; Male ; Middle Aged ; Vaccination

Avian influenza has emerged as one of the primary public health concern of the 21st century. Influenza strain H5N1 is capable of incidentally infecting humans and other mammals. Since their reemergence in 2003, highly pathogenic avian influenza A (H5N1) viruses have been transmitted from poultry to humans (by direct or indirect contact with infected birds) in several provinces of Mainland China, which has resulted in 22 cases of human infection and has created repercussions for the Chinese economy. People have been concerned whether a new pandemic will occur in the future. The eradication of pathogenic avian influenza viruses appears to be the most effective way to prevent an influenza pandemic. This paper will examine the features of H5N1, including incidence, infection, immunity, clinical management, prevention and control, and therapy in Mainland China.
Adolescent ; Adult ; Animals ; Birds ; Child ; China/epidemiology ; Disease Outbreaks/prevention & control ; Female ; Humans ; Incidence ; *Influenza A Virus, H5N1 Subtype ; Influenza in Birds/prevention & control ; Influenza, Human/*epidemiology/immunology/therapy ; Male ; Zoonoses/epidemiology/transmission/virology

Abattoirs ; manpower ; Adult ; Antibodies, Viral ; blood ; China ; Humans ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza A Virus, H3N2 Subtype ; immunology ; Influenza A Virus, H3N8 Subtype ; immunology ; Influenza A Virus, H5N1 Subtype ; immunology ; Influenza A Virus, H9N2 Subtype ; immunology ; Influenza A virus ; classification ; immunology ; Influenza, Human ; epidemiology ; prevention & control ; virology ; Middle Aged ; Population Surveillance ; methods ; Seroepidemiologic Studies ; Young Adult

PURPOSE: This study was to identify the current status of vaccination against the pandemic (H1N1) 2009 virus among university students from the fields of nursing and allied health from a local community and verify factors influencing vaccination. METHODS: The study included 227 students in the fields of nursing and allied health from a provincial university. Data were obtained from these participants between May 31 and June 11, 2010 by using self-report questionnaires. RESULTS: The rate of vaccination against the pandemic (H1N1) 2009 virus for these participants was 14.5%. No difference was observed in this regard between majors and school year. Factors that influence vaccination against this virus included previous vaccination against seasonal influenza and participants' attitudes toward general vaccination. CONCLUSION: The results suggest that for effective pandemic (H1N1) 2009 vaccination of university students from the fields of nursing and allied health, students who have not been vaccinated should be intensively managed. Developing a vaccination program that encourages a positive attitude toward vaccination is recommended.
Adult ; Attitude of Health Personnel ; Disease Outbreaks/prevention & control ; Female ; Humans ; Influenza A Virus, H1N1 Subtype/*immunology ; Influenza Vaccines/*immunology ; Influenza, Human/epidemiology/prevention & control ; Male ; Pandemics ; Questionnaires ; Students, Health Occupations/*psychology ; Students, Nursing/*psychology ; Vaccination/*statistics & numerical data ; Young Adult

INTRODUCTIONOutbreaks of acute respiratory illness occur commonly in long-term care facilities (LTCF), due to the close proximity of residents. Most influenza outbreak reports have been from temperate countries. This study reports an outbreak of influenza B among a highly immunised resident population in a welfare home in tropical Singapore, and discusses vaccine efficacy and the role of acute respiratory illness surveillance for outbreak prevention and control.

MATERIALS AND METHODSDuring the period from 16 to 21 March 2007, outbreak investigations and active case finding were carried out among residents and nursing staff at the welfare home. Interviews and medical notes review were conducted to obtain epidemiological and clinical data. Hospitalised patients were tested for respiratory pathogens. Further genetic studies were also carried out on positive respiratory samples.

RESULTSThe overall clinical attack rate was 9.4% (17/180) in residents and 6.7% (2/30) in staff. All infected residents and staff had received influenza immunisation. Fifteen residents were hospitalised, with 2 developing severe complications. Genetic sequencing revealed that the outbreak strain had an 8.2% amino acid difference from B/Malaysia/2506/2004, the 2006 southern hemisphere influenza vaccine strain, which the residents and staff had earlier received.

CONCLUSIONSA mismatch between the vaccine and circulating influenza virus strains can result in an outbreak in a highly immunised LTCF resident population. Active surveillance for acute respiratory illness in LTCFs could be implemented for rapid detection of antigenic drift. Enhanced infection control and other preventive measures can then be deployed in a timely manner to mitigate the effect of any outbreaks.

Adult ; Aged ; Disease Outbreaks ; prevention & control ; Female ; Humans ; Influenza B virus ; immunology ; Influenza Vaccines ; therapeutic use ; Influenza, Human ; epidemiology ; prevention & control ; virology ; Interviews as Topic ; Male ; Medical Audit ; Middle Aged ; Nursing Homes ; Singapore ; epidemiology ; Social Welfare ; Young Adult

This study aims to investigate the characteristics of genomic variation of pandemic A/H1N1/2009 influenza virus isolated in Fujian Province, China. Complete genome sequence analysis was performed on 14 strains of pandemic A/H1N1/2009 influenza virus isolated from Fujian during 2009-2012. All virus strains were typical low-pathogenic influenza viruses, with resistance to amantadine and sensitivity to neuraminidase inhibitors. Eight genome fragments of all strains were closely related to those of A/California/07/2009 (H1N1) vaccine strain, with > or = 98.2% homology. Compared with the vaccine strain, the influenza strains from Fujian had relatively large variation, and variation was identified at 11 amino acid sites of the HA gene of A/Fujiangulou/SWL1155/2012 strain, including 4 sites (H138R, L161I, S185T, and S203T) involved inthree antigen determinants (Ca, Sa, and Sb). In conclusion, the influenza vaccine has a satisfactory protective effect on Fujian population, but the influenza strains from Fujian in 2012 has antigenic drift compared with the vaccine strain, more attention should therefore be paid to the surveillance of mutations of pandemic A/H1N1/2009 influenza virus.
Antiviral Agents ; pharmacology ; China ; epidemiology ; Drug Resistance, Viral ; genetics ; Genome, Viral ; genetics ; Genomics ; Humans ; Influenza A Virus, H1N1 Subtype ; drug effects ; genetics ; immunology ; physiology ; Influenza, Human ; epidemiology ; prevention & control ; Pandemics ; prevention & control ; Viral Vaccines ; immunology

Animals ; Antiviral Agents ; administration & dosage ; therapeutic use ; Birds ; China ; Communicable Disease Control ; Disaster Planning ; methods ; organization & administration ; Disease Outbreaks ; prevention & control ; Global Health ; Humans ; Influenza A Virus, H5N1 Subtype ; immunology ; Influenza Vaccines ; administration & dosage ; therapeutic use ; Influenza in Birds ; epidemiology ; prevention & control ; transmission ; virology ; Influenza, Human ; epidemiology ; prevention & control ; transmission ; virology ; Poultry ; Vaccination

We aimed to compare the immune response induced by natural infection with 2009 pandemic influenza A/H1N1 (pH1N1) virus and by monovalent pH1N1 vaccination in children and adolescents. This cross-sectional clinical study was conducted at 3 hospitals in Korea from February to May 2010. A total of 266 healthy subjects aged from 6 months to 18 yr were tested for the presence of the antibody against pH1N1 using hemagglutination inhibition (HI) test. Information about pH1N1 vaccination and laboratory-confirmed pH1N1 infection history was obtained. The overall rate of HI titers of > or = 1:40 against pH1N1 was 38.7%, and the geometric mean titer (GMT) was 20.5. Immunogenicity of pH1N1 vaccination only was reflected by a 41.1% of seroprotection rate and a GMT of 22.5. Immunogenicity of natural infection only was reflected by a 61.0% of seroprotection rate and a GMT of 40.0. GMT was significantly higher in the subjects of natural infection group than in the subjects of pH1N1 vaccination group (P < 0.001). The immune responses induced by natural pH1N1 infection exceed those induced by pH1N1 vaccinations.
Adolescent ; Antibodies, Neutralizing/blood ; Antibody Formation ; Child ; Child, Preschool ; Cross-Sectional Studies ; Hemagglutination Inhibition Tests ; Humans ; Infant ; Influenza A Virus, H1N1 Subtype/*immunology/metabolism ; Influenza, Human/epidemiology/*immunology/prevention & control ; Pandemics ; Vaccination

OBJECTIVETo evaluate the effect of the aluminum hydroxide (Al-OH) adjuvant on the 2009 pandemic influenza A/H1N1 (pH1N1) vaccine.

METHODSIn a multicenter, double-blind, randomized, placebo-controlled trial, participants received two doses of split-virion formulation containing 15 μg hemagglutinin antigen, with or without aluminum hydroxide (Al-OH). We classified the participants into six age categories (>61 years, 41-60 years, 19-40 years, 13-18 years, 8-12 years, and 3-7 years) and obtained four blood samples from each participant on days 0, 21, 35, and 42 following the first dose of immunization. We assessed vaccine immunogenicity by measuring the geometric mean titer (GMT) of hemagglutination inhibiting antibody. We used a two-level model to evaluate the fixed effect of aluminum Al-OH and other factors, accounting for repeated measures.

RESULTSThe predictions of repeated measurement on GMTs of formulations with or without Al-OH, were 80.35 and 112.72, respectively. Al-OH significantly reduced immunogenicity after controlling for time post immunization, age-group and gender.

CONCLUSIONThe Al-OH adjuvant does not increase but actually reduces the immunogenicity of the split-virion pH1N1 vaccine.

Adjuvants, Pharmaceutic ; chemistry ; Adolescent ; Adult ; Aluminum Hydroxide ; chemistry ; Antibodies, Viral ; blood ; Child ; Child, Preschool ; China ; Data Interpretation, Statistical ; Double-Blind Method ; Female ; Hemagglutination Inhibition Tests ; Humans ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza Vaccines ; adverse effects ; chemistry ; immunology ; Influenza, Human ; epidemiology ; immunology ; prevention & control ; virology ; Male ; Middle Aged ; Models, Statistical ; Pandemics ; Young Adult