Chemical components analysis and morphology observation of virus in Japanese encephalitis vaccine produced from Beijing strain

The first 5 lots of Japanese encephalitis vaccines produced from Beijing-1 strain: JB011203, JB021203, JB030104, JB040204 and JB050304 were controlled of quality on chemical components and virus morphology in vaccine, using reference vaccine EJP034A (BIKEN-Japan). The results showed that: TCA-protein was 13.2- 14.5 µg/ml, the reference was 11.1 µg/ml (WHO standard 5-40 µg/ml). The thimerosal content was 82-84 µg/ml, the reference 76,3 µg/ml (WHO standard ≤120 µg/ml). The formaldehyde content was 0.061-0.063 µg/ml, the reference was 2.19 µg/ml (WHO standard ≤100 µg/ml). pH was 7.02-7.04, the reference was 7.10 (WHO stand. 6.8-7.4). The viruses morphology after negative stain were observed on electromicroscope JEM1010 with enlarge x 90.000 and x 150.000. The identical ball form of purified viruses with the intact surface antigen. 5/5 lots were passed the minimum requirements of biological products of WHO.

Study on Influenza and other viruses cause of acute respiratory infectious disease in 2001, Hanoi

Since Jan.2001 to Jan. 2002 has been collected 2,374 nasal and throat swab specimens from the patients, who were suspected influenza illness. These specimens were isolated on MDCK and Hep-2 cell line. The positive on MDCK was 3.24%, Hep-2 was 4.39%. Identification by HI and PCR. There were 77 influenza strains of which 16/77 A/New Caledonia/20/99 ( H1N1)- like virus; 4/77 A/Panama/2007/99 (H3N2)-like virus. 57/77 B/Johannesburg /5/99 – like virus. Influenza B make up 74%. It showed a peak in May with 25/57. Other viruses were isolated 39 strains from Jan to Aug.2001, of which Adeno virus 15/39 (38.46%); RSV-B 4/39 (10.26%). There was also unidentified entero viruses 20/39 ( 51.28%). The influenza occurred in Hanoi from Jan. to Dec. 2001 with sporadic cases and the main cause of influenza B virus. Adeno and Entero viruses have been isolated in association with respiratory illnesses.

Evaluation of safety and potency of Japanese encephalitis vaccine produced by Beijing-1 strai

The pilot study was performed on the first 5 lots of the Japanese encephalitis vaccine produced by Beijing-1 strain: JB011203, JB021203, JB030104, JB040204 and JB050304 to evaluate their safety and potency. The quality control consists of abnormal toxicity, specific safety, pyrogen, sterility and potency test. All of 5 lots were passed the minimum requirements of biological products of Japan. The mice and guinea pigs were healthy, body weigh increased. Non of bacteria and fungi grown in both medium Thioglycholate and Soybeancasein. The pyrogen test on rabbits was passed in 5/5 lots. Summed temperature response of 3 rabbits per lot were 0°C-0.3°C (WHO requirement ≤1.4°C). Potency test was evaluated by PRNT compared with reference EJP034A of BIKEN. After the second immunization the neutralizing antibody response > reference from 0.04 to 0.2 log. 5/5 lots were passed the safety and potency test and met the minimum requirement of biological products of WHO.