African Swine Fever Antigen Test Card (Colloidal Gold Method)

Target and Hazard: African swine fever (ASF), caused by African swine fever virus (ASFV, family Asfarviridae), is an acute, highly lethal disease of pigs listed as a Class I animal disease in China. The virus spreads via the oral and respiratory routes, blood and contaminated materials; affected pigs show high fever, cyanosis, vomiting and bloody diarrhoea, with mortality up to 90–100% in acute and subacute forms. No safe and effective commercial vaccine is available, so control relies on early diagnosis, quarantine, stamping-out and biosecurity; an outbreak can require complete herd depopulation and severely disrupt the pig industry.

Significance of Testing: The card detects ASFV antigen directly in blood and tissues for early confirmation and rapid on-site screening, helping identify the source before the virus spreads and buying time for culling and quarantine. It is intended for immediate screening of suspected cases, on-site diagnosis during necropsy, and surveillance in slaughter and transport. It is a first-line tool for early detection and rapid response to ASF.

Principle: Colloidal gold immunochromatographic assay (double-antibody sandwich): ASFV antigen in the sample binds gold-labelled antibody, migrates along the nitrocellulose membrane and is captured by the specific antibody coated on the test line (T), producing a visible line; the control line (C) confirms reagent and procedure validity.

Performance and Applications: No equipment required; visual reading within 15–20 minutes; samples: whole blood, serum, plasma or spleen, lymph node and tonsil homogenate; room-temperature storage. Suitable for rapid point-of-care screening on large pig farms, at primary veterinary stations and in slaughterhouses; any positive result must be reported and confirmed by laboratory testing per national regulations. Method: colloidal gold immunochromatographic assay (double-antibody sandwich) | Samples: whole blood, serum, plasma, spleen/lymph node/tonsil homogenate | Time to result: 15–20 min | Reading: visual assessment of T/C lines — a coloured T line indicates a positive result, C line is the procedural control | Format: tests/box (as stated on the label) | Storage: 2–30 °C, cool and dry; shelf life 18 months | Note: sensitivity, specificity, limit of detection, intra-/inter-assay CV and agreement with RT-PCR/virus isolation are subject to our internal QC report.