Taiwan Epidemiology Bulletin


Taiwan Epidemiology Bulletin

vol.39 No.2

PublishTime:2023/01/17
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Original Article

Application of WGS-PCR Method in Assisting Identification of Shigella spp.

DOI: 10.6525/TEB.202301_39(2).0001

Hsiao-Lun Wei*, Ying-Shu Liao, Ru-Hsiou Teng, Bo-Han Chen, Chien-Shun Chiou

2023 Vol.39 No.2

Correspondence Author: Hsiao-Lun Wei*

  • Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taiwan  

Abstract:

        Shigella spp. is the causative agent of shigellosis and one of the category 2 communicable diseases in Taiwan, and it causes an average of 104 local cases per year in recent 5 years. As traditional biochemical tests and serotyping cannot accurately identify some strains of Shigella spp., this becomes an obstacle for clinical laboratories to report shigellosis cases to the health departments. To improve the identification of Shigella spp., we tested clinical strains of Shigella spp. with the whole-genomic-based PCR (WGS-PCR) method. WGS-PCR method allows detection of both the phylogenic clades of Shigella spp. and the IpaH gene, an invasive gene plasmid of either Shigella spp. or EIEC. Among the 30 confirmed strains of Shigella spp., the results of WGS-PCR were 100% concordant with that of serotyping on group B, C and D strains, but only 20% consistency was found on group A strains. While using WGS-PCR to test 29 suspicious strains of Shigella spp., 2 group B strains and 2 group D strains were identified, indicating that WGS-PCR may clearly detect suspicious strains. As WGS-PCR method is a low-cost method, we recommend using WGS-PCR as a supplementary test for serotyping. 
 

Keywords:Shigella, WGS, PCR

Original Article

Update of Negative Pressure Automatic Control System in High Protection Laboratory and Review of Abnormal Events-an Example of Tainan Biosafety Level 3 Laboratory

DOI: 10.6525/TEB.202301_39(2).0002

Chung-Te Huang, Jian-Liang Liu, Chien-Chou Lin*

2023 Vol.39 No.2

Correspondence Author: Chien-Chou Lin*

  • Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taiwan 

Abstract:

        The outbreak of severe pneumonia with novel pathogens (Covid-19) in 2020 showed the importance of high-protection laboratory (BSL-3/ABSL-3 and above) and biosecurity. We addressed the improvement of the Tainan Biosafety level-3 negative pressure system as an example to demonstrate the functionality and accident handling of a negative pressure laboratory and shared the practical experience for laboratory management in Taiwan. First, each unit was monitored by the negative pressure system according to client’s demands. The intake and exhaust fan units were used in main and standby modes in turn. Biological safety cabinet (BSC) exhaust and environmental exhaust were linked to each other. There were three operational modes: the energy save mode, normal mode with BSC low airflow, and normal mode with BSC high air-flow, which saves energy by adjusting the operational situation. All parameters of the laboratory, including the value of negative pressure, temperature, and humidity, were monitored using dynamic graphics and were integrated into the central control system. The administrator could be notified via the network when an abnormal condition occurs. Secondly, according to Article 20, Item 2 of the "Administrative Measures for Infectious Biological Materials", if an abnormal event of negative pressure of high-protective laboratories occurs and cannot be recovered immediately, the event must be reported within 24 hours. Except for immediate recovery, laboratory members should notify the central and local authorities via the laboratory information management system (LIMS) in one day, and then follow the "Regulation of High Protection Laboratory Suspension Procedure" for one month or one-year suspension period. In face of the occurrence of highly infectious diseases internationally, domestic institutions are aware of the urgency of disease detection, vaccine development, and the necessary demand for high-protection laboratories. The staff of laboratory biosafety management must keep pace with the times. To maintain normal operations and handle accidental events, the staff should be familiar with basic knowledge and safety principles to avoid biohazards.

Keywords:High protection laboratory, negative pressure automatic control system, abnormal negative pressure, accident notification

Disease Surveillance

week 52, 2022–week1, 2023 (Dec. 25, 2022–Jan. 7, 2023)

DOI: 10.6525/TEB.202301_39(2).0003

Epidemic Intelligence Center, Centers for Disease Control, Ministry of Health and Welfare, Taiwan

2023 Vol.39 No.2

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