A dose-escalation safety and immunogenicity study of a new live attenuated human rotavirus vaccine (Rotavin-M1) in Vietnamese children.

We tested a candidate live, oral, rotavirus vaccine (Rotavin-M1™) derived from an attenuated G1P [8] strain (KH0118-2003) isolated from a child in Vietnam. The vaccine was tested first for safety in 29 healthy adults. When deemed safe, it was further tested for safety and immunogenicity in 160 infants (4 groups) aged 6-12 weeks in a dose and schedule ranging study. The vaccine was administered in low titer (10(6.0)FFU/dose) on a 2-dose schedule given 2 months apart (Group 2L) and on a 3-dose schedule given 1 month apart (Group 3L) and in high titer (10(6.3)FFU/dose) in 2 doses 2 months apart (Group 2H) and in 3 doses 1 month apart (Group 3H). For comparison, 40 children (group Rotarix™) were given 2 doses of the lyophilized Rotarix™ vaccine (10(6.5)CCID(50)/dose) 1 month apart. All infants were followed for 30 days after each dose for clinical adverse events including diarrhea, vomiting, fever, abdominal pain, irritability and intussusception. Immunogenicity was assessed by IgA seroconversion and viral shedding was monitored for 7 days after administration of each dose. Two doses of Rotavin-M1 (10(6.3)FFU/dose) were well tolerated in adults. Among infants (average 8 weeks of age at enrollment), administration of Rotavin-M1 was safe and did not lead to an increased rate of fever, diarrhea, vomiting or irritability compared to Rotarix™, indicating that the candidate vaccine virus had been fully attenuated by serial passages. No elevation of levels of serum transaminase, blood urea, or blood cell counts were observed. The highest rotavirus IgA seroconversion rate (73%, 95%CI (58-88%)) was achieved in group 2H (2 doses--10(6.3)FFU/dose, 2 months apart). The 2 dose schedules performed slightly better than the 3 dose schedules and the higher titer doses performed slightly better than the lower titer doses. These rates of seroconversion were similar to that of the Rotarix™ group (58%, 95%CI (42-73%)). However more infants who received Rotarix™ (65%) shed virus in their stool after the first dose than those who received Rotavin-M1 (44-48%) (p<0.05) and the percent shedding decreased after subsequent doses of either vaccine. Rotavin-M1 vaccine is safe and immunogenic in Vietnamese infants. A trial in progress will assess the safety, immunogenicity and efficacy of Rotavin-M1 (2 doses at 10(6.3)FFU/dose) in a larger number of infants. The trial registration numbers are NCT01375907 and NCT01377571.

Rota virus G1P8 isolated from acute diarrhea children with rhesus kidney cells

Twenty Rota virus strains were isolated from 20 stool specimens derived from diarrhea children in Khanh Hoa province. After 3 times of passaged culturations on MAI04 cells, there were only 2 human Rota virus strains growing well in the medium of trypsin concentration at 5 mg/ml and 4 human Rotavirus strains multiflying well in the medium of trypsin concentration at 10 mg/ml.

First report from the Asian Rotavirus Surveillance Network.

Rotavirus remains the most common cause of severe, dehydrating diarrhea among children worldwide. Several rotavirus vaccines are under development. Decisions about new vaccine introduction will require reliable data on disease impact. The Asian Rotavirus Surveillance Network, begun in 2000 to facilitate collection of these data, is a regional collaboration of 36 hospitals in nine countries or areas that conduct surveillance for rotavirus hospitalizations using a uniform World Health Organization protocol. We summarize the Network's organization and experience from August 2001 through July 2002. During this period, 45% of acute diarrheal hospitalizations among children 0-5 years were attributable to rotavirus, higher than previous estimates. Rotavirus was detected in all sites year-round. This network is a novel, regional approach to surveillance for vaccine-preventable diseases. Such a network should provide increased visibility and advocacy, enable more efficient data collection, facilitate training, and serve as the paradigm for rotavirus surveillance activities in other regions.

Isolation and selection of rotavirus strains type G4 on Rhesus kidney cells - MA104

Using rotavirus cultural methods isolated from 2001019203 strain in cellular fluid containing trypsine and rotavirus cloning method in stool samples of diarrhea children at the age of 9 months old, treated in St. Paul's Hospital in 2001. The results: 2001019203 strain was type G4, which was developed in MA 104 cellular fluids. 6/11 clones of the second cloning rotavirus were adaptable and development in cellular fluid MA104 were selected, in which only 3 clones were both adaptable and development as A-1, C-1* and E-3. All 6 adaptable colony were selected into further study

Characterization of rotavirus strains associated acute gastroenteritis among children under 5 years of age in Hai Phong children hospital from July 2001 to June 2002

41 rotavirus strains that were collected at Hai Phong Children Hospital were determined G, P genotypes by Rt-PCR method. Of these, G9 was the most common (75.62%), followed by G4 (12.19%), G1 (4.87%), and untyped (9.75%). For P genotype, P8 (46.34%), P6 (43.90%) were the most common. The common phenotype of rotavirus strains in Hai Phong Children Hospital were G9P8 (43.90%), G9P6 (21.95%), and G4P6 (12.20%)

Study on VNHR 203 strain for safety and efficacy on macaca mulatta monkey

Rota virus of the type of G4P6, 8 (VNHR 203) is one of endemic strains in Vietnam causing acute diarrhea in under- five -year -old children. In the year 2000 this strain was isolated from fecal sample of a 9 month boy with acute diarrhoae admitted to St Paul hospital. Viruses were carelully selected and underwent 10 consecutive transferred culturing on Rhesus (MA104) monkey kidney cell medium, then 20 times of assimilating on Macacca mulatta monkey primitive kidney cells.They had got high safety and efficacy in the trial on Macacca mulatta aged 12-24 months

The stability of Vietnam-producted poliomyelitis vaccine from the year 2000 to 2002

Whole studied poliomyelitis vaccine bulk lots had had sensitivity in high temperature and low concentration of NaHCO3. They all met WHO standards

Rotavirus causing acute diarrhoea in underfive children cultured on cells of kidney of African shesus

Collecting stools sample from 232 children with acute diarrhoea, who treated in hospitals. Using diagnose immune enzyme EIA bio-product branch defined that reason of the disease is rotavirus. In 10 typies of rota G1P8 that cause of disease in Vietnam only have suitable and develop 4 typies in renal cell combination of Africa Rhesus monkey are G1P8 that signed 2001019423-11, 2001019427-15, 2001019428-17, 2001019432-20

Epidemiology and disease burden of rotavitus in Vietnam in 2002

2455 fecal samples of acute diarrhoea children collected from National Institute of Pediatries, Hai Phong Pediatric hospital, Khanh Hoa Pediatric hospital, HoChiMinh city Pediatric hospitals No1 and No2 in the year 2002. By EIA assay, in 1042 samples (42.62%) Rotavirus was determined as positive. The virus existed around all the year, concentrated in Jan, Feb, March, Apr and July, affected commonly the children aged 3-35 months. From 154 genus of rotavirus, G type, G9 genus is the most common (90 genera). In addition, G2 (21 genera), G1 (19 genera), G4 (12 genera) and mixing types and unidentified types (12 genera) were also detected

G-P genotypes and phenotypes of rotavirutes recovered from Khanhhoa hospitalized children with diarrhea in 2002

By RT-PCR biomolecular technique on ARN isolated from 30% fecal mixture of 41 samples of under five years old children with acute diarrhoea due to rotavirus collected at Khanh Hoa Pediatric Hospital, the year 2002, 4 genotypes (G9, G1, G2 and G4), 3 P genotypes (P4, P6, P8) and 2 common phenotypes G1P8 and G2P4 were determined. While 9.75% of G gene and 21,95% of P gene were not determined yet

Multiphication of calf rotavirus isolates in different cell cultures

Rotavirus strains isolated from 3 acute diarrhea calves at Ba Vi cattle farm were cultured and firstly cloned in African green monkey kidney (Vero) cells and African Rhesus monkey kidney (MA104) cells. After 3 times of passage, the calf rotavirus strains were secondly cloned and all of them were adapted in primary kidney cells of Macaca mulatta

Mycoplasma in various clones of cells in the production and verification of poliomyelitis vaccine in the year 2002

Four line of cells Hep2, Vero, MA104 and JVKT are used for quality control and a line of monkey kidney cells used for production of poliomyelitis vaccine. Contaminated mycoplasma was tested by culture method and immu-mark mycotest. Same results were given: 50% of Hep 2 cells and 66.6% of MA104 were contaminated with mycoplasma. There is not any controlled lot of JVKT. Vero and monkey kidney which was contaminated

The culture of rotavirus causing acute diarrhoea in under five children on African rhesus kidney cell

10 strains of rotavirus C-1P6 causing acute diarrhoea in under 5- year - old - children were cultured on African Rhesus monkey kidney cells. Only 4 strains were adapted in the mixture of monkey MA104 kid cells. Results showed that in the most favorable medium, not all strains of virus could be adapted and grown properly. Rotaviruses of A group is the main agents causing acute diarrhoea in children in winter