GB/T 18641-2018 in English

Standard Evolution and Core Update

This standard replaces GB/T 18641-2002 version, and the main technical breakthroughs are reflected in:

• New gB antibody blocking ELISA detection method
• Introduction of gE-PCR wild virus identification technology

Comparison of diagnostic technology systems

Key technical implementation points

1. Serum neutralization test

The fixed virus dilution serum method is used. Critical control points are:

• The PK-15 cell line is required for virus titer determination
• TCID₅₀ is calculated using the Reed-Muench method
• Threshold value: titer ≥1:2 is positive

2. gE-ELISA differential diagnosis

Breakthrough in distinguishing vaccine virus from wild virus:

1. S/N value <0.6 is judged as wild virus infection
2. Suspicious samples need to be retested after 9-14 days
3. Only applicable to pig serum testing

Innovation in etiological testing

 Upstream: 5'-TTTGGATCCATGCGGCCCTTTCTG-3' Downstream: 5'-TTTGAATTCTTACGACACGGCGTCGCA-3' 

Biosafety Warning

Virus isolation and rabbit experiments must be carried out in a BSL-2 laboratory, with special attention to:

• Pathological material handling must be performed in a biosafety cabinet
• Experimental animals require dedicated isolation facilities
• Waste must be sterilized at 121℃