Background Nha Trang Institute of Vaccines Medical Biologicals has produced successfully vaccine for human influenza A/H5N1 in embryonic chicken eggs. Effectiveness of the vaccine immune response is highly dependent on the type of adjuvant used.\r\n', u'Objective: To study adjuvants for preparing A/H5N1 influenza vaccine.\r\n', u'Subjects and methods: The study used a comparative approach on capacity to increase the immune response of various adjuvants AIPO4, Chitosan and Freund tested in mice. Experiment of erythrocyte agglutination reaction is used to measure levels of antibody response in mice blood. The process of weight gain in mice after injection of vaccine adjuvant mixture is monitored.\r\n', u'Results: HA antibody level of the vaccine adjuvant mixture is higher than of the vaccine without adjuvant. Capacity of stimulating immune response of Chitosan adjuvant is higher than AlPO4. Repeat injection on day 20th is suitable for vaccine with AlPO4or vaccine without adjuvant. Repeat injection is after day 20th for vaccine with Chitosan or Freund depending on the amount of residual antibody in the blood. \r\n', u'Capacity of stimulating immune response of Freund adjuvant is the best in the 3 adjuvants but the safety of this adjuvant is low\r\n', u' Freund adjuvant should be used only for animals. When using Freund adjuvant to induce immunity to animals it should determine the amount of antibodies causing immune before repeating.\r\n', u'Conclusion: Freund adjuvant should be used only for animals. \r\n', u'\r\n', u'
Influenza A Virus ; H5N1 Subtype

OBJECTIVE: 1.To evaluates and recognizes findings in chest radiograph in patients with laboratory-confirmed S-OIV (H1N1) infection treated at UKMMC. 2. To evaluate whether the findings on initial chest radiographs of influenza A (H1N1) patients can help to predict the prognosis. MATERIAL AND METHODS: Total of 109 adult patients presenting to the Universiti Kebangsaan Malaysia Medical Centre (UKMMC) with flu-like symptoms who were positive for influenza A and these patients had underwent chest radiographs (CXR). The initial CXRs were evaluated for the pattern (consolidation, ground-glass, and reticulation), distribution, and extend of abnormality. The disease is classifies by the clinical severity (mild, moderate or severe illness) and adverse outcome (ventilated, death or recovered well). RESULTS: The initial CXRs were normal in 56% of cases. The predominant radiographic finding was consolidation, most commonly involving the middle and lower zones (35% of cases). There is no significant association between initial CXR findings with the patient clinical outcome either fully recovered or death/ ventilated. CONCLUSION: Normal chest radiographs is the most common radiographic finding in S-OIV (H1N1) infection and the most common abnormal lung finding is consolidation. Initial chest radiographs did not determine the patient clinical outcome and a normal initial radiograph could not exclude adverse outcome.
Influenza A Virus, H1N1 Subtype

Background: Mouthwashes are used to decrease oral cavity microbial load due to their antiseptic properties. Hexetidine is a broad-spectrum antiseptic used for minor infections of mucous membranes, and, as a 0.1% mouthwash for local infections and oral hygiene. Objectives: This study determined the anti-viral activity of the mouthwash hexetidine (Bactidol®), specifically in reducing viral concentration of Human Coronavirus OC43 (HCoV- OC43; ATCC®VR-1558™) and Influenza A virus (IAV H1N1; clinical strain) cultured in cell lines. Methodology: In-vitro suspension assay (ASTM E-1052-11) was used to evaluate the virucidal property of hexetidine. Tissue Culture Infective Dose or TCID50/ml in 25%, 50%, and 100% hexetidine concentration at 15- and 30-seconds were determined. Vero E6 and MDCK cell lines were utilized for HCoV OC43 and IAV H1N1, respectively. Results: Hexetidine-treated cell lines achieved >80% survival rate for MDCK and Vero E6. Hexetidine reduced the infectivity of HCoV-OC43 and IAV H1N1 at 25%, 50%, and 100% concentrations by more than 80% at 15- and 30-seconds exposure times. Conclusion and Recommendation This in vitro study showed that hexetidine, even at diluted concentrations, reduced the infectivity of HCoV-OC43 and Influenza A virus H1N1 when used for 15 and 30 seconds. The antiviral activity of hexetidine mouthwash against the other virulent members of the Coronavirus Family, SARSCoV- 2 can be explored using the methods used in this in vitro study.
Hexetidine ; Influenza A virus

Study on clinical features and epidemiology among 10 patients had avian influenza A who treated in hospital in Ho Chi Minh City and Ha Noi 12/2003 and 1/2004, 13,7 mean age. In all patients, the diagnosis of influenza A (H5N1) was confirmed by means of viral culture or reverse transcriptase polymerase chain reaction (RT-PCR) with primers specific for H5 and N1. None of the 10 patients had pre-existing medical conditions. Nine patients had a clear history of direct contact with poultry. All patients had fever, respiratory symptoms and clinically significant lymphopenia. The medium platelet count was 75.500/mm3. Seven patients had diarrhea. In all patients, there were marked abnormalities on chest radiography. There was no definitive evidence of human to human transmission, eight patients died
Influenza A Virus, H5N1 Subtype ; Influenza in Birds ; epidemiology

At the end of 2003 and early 2004, an epidemic of avian influenza with 10 cases and 7 deaths occurred in the North of Vietnam, a subtype H5N1 (A/H5N1) has been identified. The prevalence of total infection with epidemic syndrome in the whole area at the same time was 0.1%, the prevalence infected cases of death was very high (70%). The epidemic was widely distributed in 7 provinces and the highest number of cases was observed in the forth week by the onset of the first case. Sick hens were the evidence of causes. There was not direct infection from human to human. However, there were two case-clusters that happened in the same family, this may be a suggestion of biological and familial factors associated with the susceptibility to the causal virus A/H5N1
Epidemiology ; Influenza A Virus ; H5N1 Subtype ; Influenza in Birds

The occasional influenza pandemics and the seasonal influenza epidemics have destroyed millions of lives since the last century. It is therefore necessary to understand the virus replication patterns as this provides essential information on the virus infectivity, pathogenicity and spread patterns. This study aimed to investigate the replication of avian influenza A virus H5N1 (A/Chicken/Malaysia/5858/2004) in MDCK cells. In this study, the TCID50 (50% tissue culture infectious dose) of AIV H5N1 was first determined. The MDCK cells were then infected with AIV H5N1 at TCID50 for 0-48 h. The CPE (cytopathic effect) was observed and cell death was determined hourly. The virus-infected cells and media were subsequently collected for gene analysis. The results showed that the TCID50 of AIV H5N1 was 10-9 dilution. The CPE percentage showed a strong and positive correlation with the infection period (r = 1.0, n = 9, p < 0.01). The amount of a highly conserved influenza viral gene, M2 gene amplified from infected media (r = 0.471, n = 9, p= > 0.05) and infected cell (r = 0.73, n = 9, p < 0.05) were also positively correlated with the infection period. In conclusion, although CPE started to be observed in the early time points of infection, however, the M2 gene was only amplified from the infected media and cells after 48 h and 24 h, respectively. This signifies that AIV H5N1 used in this study is pathogenic and it is able to cause severe cytopathology to host cells even at low virus load.
Influenza, Human ; Influenza A Virus, H5N1 Subtype

Rapid identification of influenza A virus (H5N1) is very important for endemic control and prevention. RT-PCR method proved good rapidity. The sensitivity and the specificity is needed to be improved with complete design of primer pairs.
Influenza A Virus, H5N1 Subtype ; Diagnosis

Genomes of 24 human and avian H5N1 influenza viral strains in the Southern area of Vietnam during the 2004-2005 outbreaks were sequenced completely. All viruses containing multiple basic amino acids at the hemagglutinin cleavage site HA1-HA2 are associated with a highly pathogenic phenotype. A series of amino acid mutations located in NSl and PB2 proteins were associated with the possibility of efficient replication in mammalian tissue. The mutation in the receptor binding sites of HA that could affect binding process to human cells was found from isolates in 2004-2005 Avianflu outbreaks. All isolates are belonging to Z genotype. The findings indicated that H5Nl viruses in Vietnam have changed to be more infectious to human host in 2004-2005 Avianflu outbreaks.
Influenza A Virus, H5N1 Subtype ; Humans

Animals ; Birds ; China ; epidemiology ; Humans ; Influenza A Virus, H5N1 Subtype ; physiology ; Influenza A Virus, H7N7 Subtype ; physiology ; Influenza A Virus, H9N2 Subtype ; physiology ; Influenza A virus ; physiology ; Influenza, Human ; epidemiology ; prevention & control

In Taiwan, the first human-infecting H6N1 avian influenza virus was isolated in 2013. To better understand the origin, evolutionary relationship and pathogenesis of the H6N1 virus, we studied the adaptive evolution and evolutionary dynamics of the hemagglutinin (HA) genes of the H6N1 virus in Taiwan. We felt that such studies woud contribute to the further study and control of the virus. Datasets were gained from the Flu and Global Initiative on Sharing All Influenza Data (GISAID) databases. Then, phylogenetic trees and evolutionary dynamics were reconstructed. The evolutionary rate and characterization of adaptive evolution were analyzed by bioinformatic methods. Results indicated that the HA genes of H6N1 in Taiwan were divided into at least five types, and that the new types that the infected human H6N1 belonged to could be local advantage type at present. Evolutionary dynamics revealed the viral population expanded first at the end of 1971, reduced sharply in 2008, and then increased slightly. Three sites were identified under positive selection, suggesting that various sites might increase the adaptive ability of the virus. Eighty-nine sites were under negative selection, revealing that these sites might play an important role in the replication and epidemiology of the virus. Interestingly, site 329 upstream from the cleavage site was also under negative selection, suggesting that this site might be associated with the virulence of H6N1. These data suggest that the HA genes of the Taiwanese H6N1 virus have been undergoing adaptive evolution, and that an outbreak may occur again. Hence, more attention should be paid to the identified sites, to enable timely monitoring and control of a future epidemic.
Animals ; Birds ; Evolution, Molecular ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; Influenza A virus ; genetics ; Influenza in Birds ; virology ; Taiwan