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

No abstract available.
Humans ; Influenza A Virus, H1N1 Subtype/*isolation & purification ; Influenza, Human/*diagnosis

Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human ; epidemiology ; virology

Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human ; epidemiology ; virology

Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human ; epidemiology ; virology

During the past 100 years, there had been four global pandemics on influenza that had greatly influenced the health and life of the people. This article summarized the features, experiences and lessons learned on these four influenza pandemics so as to prepare related measures targeting the possible pandemics/epidemics in the foreseeable future, in China.
China ; Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human/epidemiology* ; Pandemics

Disease Outbreaks ; Humans ; Influenza A Virus, H1N1 Subtype ; physiology ; Influenza A Virus, H5N1 Subtype ; physiology ; Influenza, Human ; epidemiology ; prevention & control ; transmission ; virology

To understand the evolutionary characterization of HA1 of H1N1 influenza virus HA gene circulaing from 1981 to 2005 in China, viral RNAs of 370 H1N1 strains were extracted and transcribed into cDNA by reverse transcriptase and amplified by PCR. The products of PCR were sequenced. The sequences were analyzed through biometic software. The results showed that all the four antigenic sites were mutated, bigger change occurred on the Sb and Ca sites; the 130 loop of receptor binding sites(RBS) of HA1 amino acid deleted at the 134th site in 1991 firstly, then the number of the deleted strains were increasing, since 2000, all the strains had deleted at the 134th site, and simultaneously, the amino acid at 137th site was substituted by S for T. The change of HA1 glycosylation sites was found and 7 sites kept stable from 2000 to 2005. The H1N1 strains of the same year almost clustered in the same group on the phylogenetic tree and were irrelevant to virus isolated time and area. There appeared two groups of 2005 H1N1 virus strains that differed in time of virus isolation.
China ; Genes, Viral ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; Influenza A Virus, H1N1 Subtype ; genetics ; Phylogeny ; Time Factors

Objective: To analyze the genetic characteristics of the first human infection with the G4 genotype of Eurasian avian H1N1 swine influenza virus (EA H1N1 SIV) in Shaanxi Province. Methods: The patient's throat swab samples were collected, and MDCK cells were inoculated for virus isolation to obtain the virus strain. The whole genome deep sequencing method was used to obtain the eight gene segments of the isolated strain. The nucleotide homology analysis was conducted through the Blast program in the GenBank database, and a phylogenetic tree was constructed to analyze the genetic characteristics of the virus. Results: The throat swab specimens of the case were confirmed as EA H1N1 SIV in the laboratory, and the isolated strain was named A/Shaanxi-Weicheng/1351/2022(H1N1v). Homology analysis found that the PB2, NP, HA, NA, and M genes of this isolate had the highest nucleotide homology with A/swing/Beijing/0301/2018 (H1N1), about 98.29%, 98.73%, 97.41%, 97.52%, and 99.08%, respectively. The phylogenetic tree showed that the isolate belonged to G4 genotype EA H1N1 SIV, with PB2, PB1, PA, NP and M genes from pdm/09 H1N1, HA and NA genes from EA H1N1, and NS gene from Triple-reassortant H1N1. The cleavage site of the HA protein was IPSIQSR↓G, which was the molecular characteristic of the low pathogenic influenza virus. No amino acid mutations associated with neuraminidase inhibitors were found in the NA protein. PB2 protein 701N mutation, PA protein P224S mutation, NP protein Q357K mutation, M protein P41A mutation, and NS protein 92D all indicated its enhanced adaptability to mammals. Conclusion: The patient is the first human infection with G4 genotype EA H1N1 SIV in Shaanxi province. The virus is low pathogenic, but its adaptability to mammals is enhanced. Therefore, it is necessary to strengthen the monitoring of such SIVs.
Swine ; Humans ; Animals ; Influenza A Virus, H1N1 Subtype/genetics* ; Phylogeny ; Genotype ; Influenza A virus ; China ; Birds ; Mammals

Objective: To analyze the genetic characteristics of the first human infection with the G4 genotype of Eurasian avian H1N1 swine influenza virus (EA H1N1 SIV) in Shaanxi Province. Methods: The patient's throat swab samples were collected, and MDCK cells were inoculated for virus isolation to obtain the virus strain. The whole genome deep sequencing method was used to obtain the eight gene segments of the isolated strain. The nucleotide homology analysis was conducted through the Blast program in the GenBank database, and a phylogenetic tree was constructed to analyze the genetic characteristics of the virus. Results: The throat swab specimens of the case were confirmed as EA H1N1 SIV in the laboratory, and the isolated strain was named A/Shaanxi-Weicheng/1351/2022(H1N1v). Homology analysis found that the PB2, NP, HA, NA, and M genes of this isolate had the highest nucleotide homology with A/swing/Beijing/0301/2018 (H1N1), about 98.29%, 98.73%, 97.41%, 97.52%, and 99.08%, respectively. The phylogenetic tree showed that the isolate belonged to G4 genotype EA H1N1 SIV, with PB2, PB1, PA, NP and M genes from pdm/09 H1N1, HA and NA genes from EA H1N1, and NS gene from Triple-reassortant H1N1. The cleavage site of the HA protein was IPSIQSR↓G, which was the molecular characteristic of the low pathogenic influenza virus. No amino acid mutations associated with neuraminidase inhibitors were found in the NA protein. PB2 protein 701N mutation, PA protein P224S mutation, NP protein Q357K mutation, M protein P41A mutation, and NS protein 92D all indicated its enhanced adaptability to mammals. Conclusion: The patient is the first human infection with G4 genotype EA H1N1 SIV in Shaanxi province. The virus is low pathogenic, but its adaptability to mammals is enhanced. Therefore, it is necessary to strengthen the monitoring of such SIVs.
Swine ; Humans ; Animals ; Influenza A Virus, H1N1 Subtype/genetics* ; Phylogeny ; Genotype ; Influenza A virus ; China ; Birds ; Mammals