ABSTRACT
Objective@#To analyze the epidemiological characteristics and the pathogenic features of the influenza B virus strains circulating in Anhui province during 2017-2018 influenza surveillance year.@*Methods@#The antigenic characteristics of influenza B virus was analyzed with reference ferret anti-sera. The hemagglutinin (HA) and neuraminidase (NA) genes of influenza B viruses isolated in Anhui during this period were obtained by Sanger dideoxy sequencing. Then the phylogenetic trees and amino acid mutations were analyzed respectively.@*Results@#During 2017-2018 influenza season, the activity of B Yamagata lineage virus were stronger than B Victoria lineage virus. Most of B Yamagata lineage viruses had close antigenic relation with the vaccine strain B/Phuket/3073/2013(93.3%), but D196 N substitution was detected on HA protein in all of Yamagata lineage viruses. All of B Victoria lineage viruses had close antigenic relation with the vaccine strain B/Brisbane/60/2008(100%), meanwhile I117 V and N129D were found on HA protein. Phylogenetic analysis on B influenza viruses indicated that Yamagata clade 3 and Victoria clade 1A were predominant strains, however we found that two strains had intra-clade reassortants between HA and NA gene. The NA gene of all strains did not find a molecular mutation that was less sensitive to neuraminidase.@*Conclusions@#The WHO recommended influenza vaccine could protect from influenza B virus isolated from Anhui province. However, it is still necessary to pay close attention to its significant epitope variation in order to update the vaccine candidates in time.
ABSTRACT
Objective To analyze the distribution of various genotypes of human cytomegalovirus glycoprotein N ( HCMV gN) in patients with HIV infection; to investigate the effects of HCMV-HIV co-in-fection on disease progression and the relationships between HCMV gN genotypes and disease progression. Methods Patients with active HCMV infection were screened out from 359 patients with HIV infection by using the pp65 antigenemia assay.The genes encoding HCMV gN ( UL73 ) were amplified by nested PCR ( nPCR) .The amplicons were digested by restriction enzymes including MboⅠ, ScaⅠ and SalⅠ.Then, the restricted fragment length polymorphisms were further analyzed on 4%agarose gel.The relationships be-tween HCMV genotypes and the morbidity and mortality of acquired immune deficiency syndrome ( AIDS ) were investigated via a prospective study.Results Among the 359 patients with HIV infection, 28 subjects were positive for the HCMV pp65 antigenemia assay.The HCMV gN genotypes in 20 patients with active HCMV infection were distributed as: gN-3a (4/20, 20%), gN-1 (4/20, 20%), gN-4d (1/20, 5%), gN-4b (1/20, 5%) and mixed infection (10/20, 50%).Patients with HCMV-HIV co-infection were more likely to develop AIDS during the follow-up period (RR=9.78).Patients harboring HCMV gN-1 and gN-4 genotypes would seem likely to have 4.6 times of chance leading to AIDS-associated death than those harbo-ring other HCMV gN genotypes.Conclusion HCMV infection ( especially gN-1 and gN-4 genotypes) might accelerate the progression of HIV infection.