Study on the stable of gene sequence of seed lot system G1P8 KH0118 during production rotavirus vaccine

Background: Rotavirus strain (KH0118) is used as the primary material to produce original rotavirus vaccine strains with the symbol of G1P8 MS. According to the World Health Organization\u2019s standard, the strain is needed to evaluate the stability of gene throughout analysis of gene and amino acid sequence during vaccine production. Objective: To determine the sequence of genes 4 (VP4), 6 (VP6), 9 (VP7) and 10 (NSP4) with base pair correlative 855:866:1345:745 of seed lot system and vaccine of G1P8 strain and to evaluate the stability of seed lot system during vaccine production. Subject and methods: ARN was divided from the original strain of rotavirus vaccine G1P8 MS, rotavirus vaccine productive strain (G1P8 WS) and rotavirus vaccine (G1P8 VX). Then using primer pairs to determine gene sequence VP4, VP6, VP7, NSP4 and comparing gene and amino acid sequence of the seed lot system. Results and Conclusion: The study demonstrated that, there was no difference for the nucleotide and amino acid sequence from the original strain during production of rotavirus vaccine G1P8 KH0118.

Epidemiology of rotavirus diarrhea in the National Pediatric Hospital

Background: Rotavirus type A is the most common cause of acute gastrointestinal inflammatory in children under 5 years old, especially in age groups 6 and 36 months. Some rotavirus strains are common; seen recently in Vietnam are G1, G2, G3, G4 and G9, P4, P6 and P8. Objective: Surveillance of epidemiological characteristics of rotavirus induced diarrhea in the National Pediatric Hospital from September, 2007 to March, 2008. Subject and methods: Collection of 322 stool specimens of pediatric patients with acute diarrhea (including 213 specimens from male, 109 specimens from female), who were treated in the National Pediatric Hospital. All of these specimens were determined for causes of rotavirus with the enzyme immunoassay (EIA). Results and Conclusion: Among these 322 stool specimens, there were 195 rotavirus positive specimens, accounted for 60.56%. The rate of monthly distribution of rotavirus diarrhea from September, 2007 to March, 2008 were 76%, 56%, 62%, 61%, 64%, 56% and 44%, respectively. Number of rotavirus positive cases in male and female was 56 (26.29%) and 79 (72.48%), respectively. The rate of rotavirus positive children compared to total number of specimens with the age 0-3 months, 3-6 months, 6-12 months, 12-24 months, 24-36 months and over 36 months was 7.69%, 15.9%, 41.54%, 32.82%, 1.54% and 0.51%, respectively. The results of type identification indicated that phenotypes of 37 among 40 specimens were identified (92.5%) in which there were 5 specimens of G1P8 (12.5%), 20 specimens of G3P8 (50%), 1 specimen of G9P8 (2.5%), 2 specimens of G1Pmixed (5%), 9 specimens of G3Pmixed (22.5%), 1 specimen of G unidentified-type P8 (2.5%) and 2 specimens of G3 P unidentified-type (5%).

Stable study of gene sequence of seed lot system G1P4 (2001019210) during production of rotavirus vaccine

Background: Presently, toxicity decreased oral live rotavirus is a candidate for vaccine for the prevention of rotavirus induced diarrhea. According to the World Health Organization, the seed lot system is robustly checked, in which determining the stable of gene sequence. Objective: To determine the sequence of genes 4: 6: 9: 10 with base pair correlative 855: 824: 1314: 734 of seed lot system G1P4 (2001019210) during production of rotavirus vaccine. Subject and methods: Gene 4 (VP4), gene 6 (VP6), gene 9 (VP7) and gene 10 (NSP4) of seed lot system G1P4 were determined for gene sequencing and then comparing the nucleotide sequence as well as deduced amino acids from original strain with the produced strain and vaccine virus. Results and Conclusion: There was no different for nucleotide and deduced amino acid sequence from the original strain during the production of rotavirus vaccine of G1P4 MS (2001019210) to producing strains of G1P4 WS and vaccine strains of G1P4 VX.

Epidemiology of ROTA virus diarrhea in Ho Chi Minh city from 12/2006-11/2007

Background: Acute gastroenterophathy usually caused by the Rota virus for children under 5 years old. Objectives: To present various types of data on epidemiology of ROTA virus diarrhea in Ho Chi Minh city from 12/2006-11/2007. Material and method: The data were collected from 500 stool specimens of diarrhea diagnosed chilren hosptalised at Thuy Dien Pediatric hospital 1, Ho Chi Minh city from December/2006 to November /2007. Results:There were 322 rotavirus-positive specimens, representing 64.4%. The proportions of monthly distribution of cases with diarrhea due to rotavirus were 90.1%, 54.39%, 85.37%, 74.51%, 72.92%, 41.67%, 26.67%, 58.33%, 79.31%, 52.63%, 69.05% and 57.78%, respectively. The numbers of rotavirus-positive cases in male and female were 216 (65.26%) and 106 (62.72%), respectively. The proportions of Rota virus positive children compared to total number of diarrheal cases with age 0-3, 3-6, 6-12, 12-24, 24-36 and over 36 months were 2.80%, 7.76%, 40.06%, 40.68%, 5.28% and 3.42%, respectively.\r\n', u'The results of typing identification indicated that the phenotypes of 98 among 100 specimens were identified (98%) in which there were sixty-one specimens of G1P8 (61%), one specimen of G2P8 (1%), fourteen specimens of G3P8 (14%), four of specimens of G4P8 (4%), eighteen specimens of GmixedP8 (18%). There were only two specimens of GnontypeableP8 (2%). Conclusion: Further studies should be carried out to clear this issue.\r\n', u'

Study on the stability of gene sequences of seed lot system G4P6 (2001019203) during production of rotavirus vaccine

Background: Currently, the World Health Organization is encouraging developing countries to establish a seed lot system of rotavirus vaccine for production of this vaccine. Objectives: To determine gene sequences of rotavirus strain that was used for vaccine production and to evaluate its stability. Materials and method: Master seed (G4P6MS), Working seed (G4P6WS) and vaccine strain (G4P6VX) of Rotavirus were used for analysis at the US Center for Disease Control and Prevention (CDC). Results: 855 base pairs of gene 4 (VP4); 1195 base pairs of gene 6 (VP6); 824 base pair of gene 9 (VP7) and 715 base pairs of gene 10 (NSP4) from seed lot system and vaccines of G4P6 strain were determined. The results demonstrated this seed lot system is completely stable during vaccine production. There is no difference for nucleotide and amino acid sequence in this seed lot system. Conclusion: G4P6 strain (2001019203) is completely stable during vaccine production.