Drug resistance and molecular characteration of hemagglutinin and neuraminidase for influenza A H3N2 viruses / 医学研究生学报

Objective　To analyze the variations and drug resistance of influenza A (H3N2) viruses in Jiangsu Province in 2017, and provide evidence for prevention and control strategies on influenza.　Methods　Reverse transcription polymerase chain reaction (RT-PCR) was used for the sequencing of H3N2 subtype influenza strains. The influenza reference sequences were obtained from the global shared influenza site GISAID. The sequence alignment and phylogenetic analysis were performed using MAGE7.0 software. Viral resistance was analyzed by a neuraminidase inhibition assay.　Results　The H3N2 subtype influenza isolates and vaccine strains belonged to the 3C.2a branch of the H3 subtype. Some of the strains showed amino acid mutations on the immune-related sites named N121K, T135K and N171K. The isolates were sensitive to the flu drugs oseltamivir and zanamivir.　Conclusion　The H3N2 epidemic strains in Jiangsu have genetic recombination within subtypes and are still sensitive to neuraminidase inhibitors. As the H3N2 influenza virus mutations continue, a close monitoring of the viral genetic evolution and the drug resistant genes should be guaranteed.

Molecular features of human bocavirus from infantile diarrhea in Suzhou area, Jiangsu province in 2010-2011 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the status of human bocavirus and to identify its epidemiological characteristics as well as genotype distribution in patients with infantile viral diarrhea in Suzhou, Jiangsu province.</p><p><b>METHODS</b>832 fecal specimens from patients with infantile virus diarrhea cases were collected from Suzhou Children's Hospital in 2010-2011. Human bocavirus were detected by Real-Time RT-PCR, and genotype were determined by sequence analysis.</p><p><b>RESULTS</b>Among all the fecal specimens, 51 (6.1%) cases were positive for human bocavirus. The peak season of rotavirus infection was between July and September. Of all the episodes on rotavirus diarrhea, 96% occurred before 2 years of age, with peaks in children with 7-12 months of age. Data from Nucleotide Sequence analysis showed that among 28 samples that carrying HBoV-1, 5 strains belonged to HBoV-2, HBoV type 3 but type 4 were absent.</p><p><b>CONCLUSION</b>Human bocavirus were detected from fecal specimens of infantile virus diarrhea in Suzhou, with genotype HBoV-1 as the major strain. HBoV-2 genotype was also found.</p>

Serologic survey on pandemic influenza A (H1N1) virus among aged ≥3 years population from Jiangsu province in 2009, China / 中华流行病学杂志

Objective To understand the antibody levels against pandemic influenza A (H1N1) virus (2009 H1N1 ) among aged ≥3 years population in 2009, from Jiangsu province, and to describe the distribution of 2009 H1N1. Methods Serum specimens were collected from natural populations at four different periods in Jiangsu, and tested with hernagglutination-inhibition (HI)assays. Rates of protective antibody against 2009 H1N1 and Geometric mean titers (GMTs)were estimated. Results The rates of protective antibody against 2009 H1N1 rose with the and November, 2009. There were no significant differences on the rates of protective antibody between males and females at four different cross-sectional periods (P＞0.05), and no significant differences on GMTs were observed at different periods except for November 2009. Significant differences on rates of protective antibody and GMTs among various age groups were observed at four different periods (P＜0.05), and similar results were observed among different periods in various age groups (P＜0.05). There were significant differences on rates of protective antibody and GMTs among different areas (P＜0.05). Conclusion The 2009 H1N1 strain had been widely spread out in Jiangsu province since July 2009. People aged 12-17 years became the major victims after August. As of November 2009, the rate of protective antibody against 2009 H1N1 was still low, predicting that the epidemic might continue to exist for a certain period of time.