On September 24, 2004, PulseNet China held the first meeting in Beijing. The central laboratory is in National institute for Communicable Disease Control and Prevention, and State Key laboratory for Infectious Disease Prevention and Control, China CDC. Within these years PulseNet China were working on central laboratory establishment, technical learning, protocol optimization and evaluation of some special pathogens, database construction, PFGE training to other laboratories, and practice in response to outbreaks.
Foodborne pathogens included in PulseNet China
E. coli O157:H7, Vibrio cholerae, Salmonella typhi and paratyphi, Shigella, Yersinia enterocolitica, Campylobacter jejuni, Listeria monocytogenes.
Other bacteria pathogens:
Nesseria meningitidis, Yersinia pestis, Leptospira interrogans, Streptococcus suis.
Up to March 2007, high-quality patterns of more than 2,600 strains were recorded in the database of the central laboratory:
- V. cholerae (O1 and O139): 165 patterns from 454 strains;
- E. coli O157:H7: 161 patterns from 300 strains;
- Shigella: 68 patterns from 273 strains;
- S. typhi and paratyphi A: 173 patterns from 747 strains;
- Y. enterocolitica: 212 patterns from 419 strains;
- L. monocytogenes: 39 patterns from 118 strains;
- S. suis: 61 patterns from 108 strains;
- N. meningitidis: 43 strains from 212 strains.
All the Isolates recorded in the central laboratory database are collected from more than 20 provinces. In the database, isolates came from Strain Banks in China CDC (collected from different provinces in different years), recent outbreaks in some provinces (the isolates were transferred into the lab in China CDC, the central lab, to run PFGE). The data of other bacteria, and of other provincial laboratries are under collected and estimated.
PulseNet China is trying to optimize the PFGE protocol of Leptospira interrogans. Based on the other PFGE protocols of other pathogens provided by PulseNet, the methods for chromosome DNA purification, restriction endonuclease digestion and the parameters for running PFGE were optimized. The Not I patterns of partial isolates of serogroup icterohaemorrhagiae in the surveillance in Sichuan province were analyzed.
PFGE capacity in Provincial CDC's laboratories
More than 10 provincial CDC laboratories have been equiped with PFGE instruments (Bio-Rad CHEF Mapper or DR III). Up to now the PFGE pattern form half of these laboratories can be analyzed directly with BioNumerics. Fifty-eight professional technicians from 29 province- and city-level CDC have been trained in the central laboratory, including specialized training, to do PFGE analysis of the strains collected historically in surveillance, and the strains from response to outbreaks.
Ongoing work and the work in the future
In 2007 the key work in PulseNet China is focusing on network management, regulations, data exchange and training. The regulations include procedure of the analysis, validation and certification of the new laboratories when joining the network, cooperation agreement (memorandum of understanding) to the network laboratories, and construction of QA/QC system of the network. The network will be managed based on these regulations.
Data exchange is the challenge in PulseNet China. Now the primary manner of data exchange is email. The possibilty of discussion forum of PulseNet China is under evaluation.
For further information please contact:
Dr Jianguo Xu, Director, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, P.R.China.
China hosted the fourth meeting of PulseNet Asia Pacific in Nanjing, 19-21 December 2006.