Genetic characterization analysis on epidemic rubella virus strains isolated in Liaoning from 2007 to 2012 / 病毒学报

To analyze the genetic characterization of epidemic rubella virus strains isolated in Liaoning from 2007-2012, a total of 145 rubella virus strains were isolated using Vero/Slam cell line from the patients' throat swabs during rubella outbreaks and sporadics cases in Liaoning Province from 2007 to 2012. Fragments of 945 nucleotides containing 1E gene from 145 rubella virus isolates were amplified by RT-PCR, the PCR products were sequenced and analyzed. Based on the 739 nucleotides of 1E gene, the phylogenetic trees were constructed with 32 WHO rubella reference strains of 13 genotypes downloaded from GenBank and 145 rubella virus strains. The results showed that the 145 rubella virus strains in 2007 -2012 belonged to genotype 1E, nucleotide acids and amino acids similarities were 97.2%-100.0% and 97.6%-100.0%, respectively. Compared to the 1E reference strains(Rvi/ Dezhou.CHN/02, RVi/MYS/01), the nucleotide acids and amino acids similarities were 96.6%-99.2% and 98.2%-100.0%, respectively except for one amino acid change (Val246-Ala246) of RVi/Shenyang. Liaoning. CHN/13.11/13, and Asp262-Asn262 of RVi/Shenyang. Liaoning. CHN/13.11/4 and RVi/Liaoyang. Liaoning. CHN/26. 11/2. there had no change found in the important antigenic epitope sites, the hemagglutination inhibition and neutralization epitopes of the other rubella viruses. All the 145 strains isolated had the same amino acid change (Leu338--Phe338) in E1 protein. These findings suggested that genotype 1E of rubella virus was the predominant genotype in Liaoning province. the rubella prevailed in recent six years was mainly caused by rubella viruses genotype 1E with multi-transmission routes.

SH protein genetic characterization analysis of wild-type mumps virus isolated in Liaoning province from 2008 to 2011 / 病毒学报

A total of 13 mumps virus strains were isolated using Vero/Slam cell line from the patients' throat swabs and urines during mumps outbreaks and sporadics in liaoning Province from 2008 to 2011. Fragments of 316 nucleotides containing SH genes from 13 mumps virus isolates were amplified by RT-PCR, the PCR products were sequenced and analyzed. Based on the 316 nucleotides of SH gene, the phylogenetic trees were constructed with WHO mumps reference strains downloaded from GenBank and 13 mumps virus strains. It showed that the 12 mumps virus strains in 2008-2011 belonged to F genotype, nucleotide acids and amino acids similarities were 94.9%-100.0% and 83.3%-100.0%. Compared to the F reference strains, nucleotide acids and amino acids similarities were 92.4%-97.2% and 96.5% 84.2%, indicating that liaoning mumps strains had large genotype variation. Furthermore, compared to other genotype mumps strains, 6 nucleotides mutations (C(Nt65), C(Nt105), G(Nt137), C(Nt192), C(Nt239), G(NT262)) in SH gene were shared in all of liaoning F genotype mumps viruses. However these mutations were not found in other genotypes of mumps viruses. Conserved amino acids in SH protein of some liaoning mumps strains had changed (S to P at position 2 P to L at position 6 T to N at positon 23 L to P/R at position 48). The genotype specific triplet IML (at position 28-30) was changed to TMP in strain 2008-001-007 2011-015 s, nucleotide acids and amino acids similarities of strain 2008-001-07 were 87.5% and 79.8%, compared to F reference strains respectively, and 96.8% and 97.4% respectively compared to the G reference strains, in dicating strain 2008-001-07 belonged to G genotype,which was first found in mainland China.

Isolation of the Culex flavivirus from mosquitoes in Liaoning Province, China / 病毒学报

A flavivirus, Culex flavivirus, was first isolated from Chinese mosquitoes with high sequences similarities to those of flaviviruses found in America and Japan. In this study, a total of 48 pools of field-collected mosquitoes were sampled from Dandong of Liaoning Province, China during July to September of 2011. Six isolated viruses showing cytopathic effect (CPE) in C6/C36 cells were tested by reverse transcription polymerase chain reaction(RT-PCR)using Flavivirus genus--specific primers and Culex flavivirus-specific primers and the positive PCR-product was sequenced and compared with the sequences of 10 isolates from GenBank. Phylogenetic tree of NS5 and enevelop genes of flavivirus were constructed. The GenBank accession numbers of NS5 gene were JQ409188, JQ409186, JQ409187, JQ409191, JQ409189 and JQ409190. The GenBank accession numbers of envelope gene were JQ065883, JQ065882, JQ065881, JQ065879,JQ065877 and JQ065878.

Genetic characterization of wild-type mumps virus isolated in Liaoning Province / 病毒学报

Three mumps virus strains were isolated using Vero/Slam cell line from the patients' throat swabs and urines during mumps outbreaks and sporadic period in Liaoning province from 2008. Fragments of 1028 nucleotides including SH genes from 3 mumps virus isolates were amplified by RT-PCR, the PCR products were ligated into pMD19-T vector and cloned to JM109 cell. By blue-white selection, the positive white clones were sequenced and analyzed. Based on the 316 nucleotides of SH gene, the phylogenetic analyses were processed with WHO mumps reference strains downloaded from GenBank and 3 mumps viruses strains. It wan shown that the 3 mumps virus strains isolated in 2008 belonged to F genotype, 3 strains (LN-2008-001-06, LN-2008-001-07 and LN-2008-001-10) showed a nucleotide and amino acid similarity of 98.7%-100% and 94.7%-100% respectively. Two strains (LN-2008-001-06 and LN-2008-001-10) had the same sequence completely. Comparing to the F reference strains, the 3 mumps virus strains' nucleotide and amino acid similarity of 92.4%-96.2% and 84.2%-94.7% respectively. Due to the limited strain numbers, whether the F genotype was the predominant circulating genotype can not be determined. The surveillance on the mumps virus in Liaoning should be therefore strengthened.

Application of global positioning systems and geographic information systems in drinking water defluoridation project in Liaoning province / 中国地方病学杂志

Objective To establish information management systems of drinking water defluoridation project in water-related endemic fluorosis areas and investigate the status of drinking water defluoridation project in Liaoning, provide the basis for the development of control measures. Methods Global positioning systems (GPS)and geographic information systems(GIS) were used in the study in August 2006 - July 2008. Water defluoridation projects of 1234 in 48 counties(cities, districts) in drinking water type of fluorosis areas were positioned. Latitude and longitude, water samples, water fluoride content were collected or tested. GIS was used to establish information management system of water defluoridation projects. Results We have established information management system for the facilities of decreasing water fluorine in drinking water type of endemic fluorosis regions in Liaoning. One thousand two hundred and thirty four defluoridation facilities distributed in east longitude between 39.39° - 43.37°,north latitude between 119.25° - 125.50°, and altitude between - 6.60 and 801.14 meter in 48 endemic fluorosis counties in 13 cities. Nine hundred and twenty seven facilities for decreasing fluorine were able to supply water regularly, accounting for 75.1% of investigated projects;29 facilities was .not yet completely rebuilt, accounting for 2.4%;278 facilities(supply water for 344 villages) were out of order or discarded for 22.5% of investigated projects.Water fluorine contents of 63 facilities were greater than 1.2 mg/L, accounting for 6.8% of investigation project.Facilities working regularly and water fluorine was in accord with hygienic standard for drinking water facilities were 70.0%. Conclusions The establishment of Liaoning province defluoridation project information management system in the whole province of drinking water type of fluorosis areas provides scientific basis for accurate decision-making on prevention and control of the disease.