Discovery and response of the first case of human infection with avian influenza A(H9N2) virus in Yunnan Province, China / 中国人兽共患病学报

We investigated and analyzed the first case of human infection with avian influenza A(H9N2) virus in Yunnan Province,China,so as to provide a better basis for preventing and controlling human infections with viruses of animal origin in the future.We carried out the field epidemiological survey among the patient,close contacts and the live poultry markets,detected and analyzed the samples from patient and the outdoor environment.Results showed that the 9-month-old boy was a case of human infection with avian influenza A(H9N2) virus with the history of live poultry markets exposure and the results of nucleic acid detection and virus isolation.There was a lot of contamination of the avian influenza virus in the live poultry markets.The second generation cases have not occurred.The monitoring of pneumonia of unknown etiology and influenza like cases in medical institutions is the important means to find timely cases of human infected with avian influenza.Regular disinfection and closing-down of live poultry markets are key measures to reduce the exposure opportunity.

Phylogenetic Analysis of Influenza B Hemagglutinin Gene in Yunnan from 2009 to 2014 / 昆明医科大学学报

Objective To investigate the mutation of hemagglutinin gene and amino acid variation of influenza B.Methods Influenza B virus was isolated from throat swab samples in sentinel surveillance of Yunnan province from 2009 to 2014.HA1 gene sequence analysis was applied to determine 12 randomly-selected strains of influenza B virus.The results were analyzed,MEGA software was used to do homology comparison and HA gene phylogenetic tree was established.Results Differences on the serotype and genotype identification of influenza strains were found and it might be caused by inadequate gene mutation accumulation.Amino acid variations were found in 3 important regions of antigenic determinants in HA1 protein:ring 120,ring 150 and ring 160.The amino acid variation of position 131 in ring 120 was N131K,and in position 137 was N137H.Two strains had P187S mutation in position 187.Conclusion There are some important variations in the hemagglutinin gene of influenza B strains in Yunnan Province,with some variations being the same as vaccine strains and some being not.

Analysis of HA and NA Genes of Influenza A H1N1 Virus in Yunnan Province during 2009-2014 / 病毒学报

To analyze influenza pathogen spectrum in Yunnan province during 2009-2014 years, and analyze HA and NA genes of influenza A H1N1. Analysis was made on the monitoring date of influenza cases in Yunnan province in recent 6 years, 23 strains of influenza virus of HA and NA gene was sequenced and analyzed by MEGA 5 software to construct phylogenetic tree. 4 times of influenza AH1N1 epidemic peak were monitored from 2009-2014 years in Yunnan Province, as the nucleic acid detection results of influenza A H1N1 accounted for 28.8% of the total. The sequencing result showed that HA and NA gene were divided into 3 groups, one was detected with H275Y mutation strains. Influenza A H1N1 is one of the important subtypes in Yunnan province and their genes have divided into three branches during the period of 2009-2014 years, the vast majority of influenza a H1N1 are still sensitive to neuraminidase inhibitors.

Viral Etiology Analysis of Acute Respiratory Tract Infection in Kunming Area / 昆明医科大学学报

Objective To understand the viral etiology of acute respiratory infection in Kunming area. Methods We collected the nasopharyngeal swab of patients with acute respiratory tract infection,and used multiple reverse transcription-polymerase chain reaction (RT-PCR) method to detect 15 kinds of respiratory viral pathogens. Results Among the 600 samples,144 strains of viruses were detected, the positive rate was 24%,among which the highest positive rate was RSV (49/600,8.2%),followed by PIV (32/600,5.3%) HRV (27/600,4.5%) and IFV27 (27/600,4.5%) . The respiratory virus infection situation was different in every age group, groups of the highest virus positive rate was ≤1 age group (72/216, 33.3%);The respiratory virus infection situation in different seasons was different, the virus positive rate of the first quarter was the highest (85/144, 59%) . Conclusion RSV was the main virus pathogen of acute respiratory tract infections in Kunming area in 2011 years, the detection rate in sick children was the highest among all patients;the detection rate in the first quarter was higher than other quarters.