VHOSPITAL.CLINIC · Diagnostic Test
Trichinella ELISA detects IgG antibodies against Trichinella spiralis excretory-secretory (ES) antigens — the primary diagnostic test for trichinellosis after the initial eosinophilia phase.
Serology becomes positive 3–5 weeks after infection — after the initial intestinal phase. Combined with eosinophilia, elevated CK/LDH, and dietary history (undercooked meat), ELISA confirms trichinellosis non-invasively and avoids muscle biopsy in most cases.
Venous blood sample. ELISA using Trichinella larval or ES antigen. IgG titers reported. Western blot confirmation is used when ELISA is equivocal. Serial testing at 2–4 week intervals shows rising titres in acute infection. IgG can remain detectable for years post-infection.
Negative serology in first 3 weeks does not exclude trichinellosis. Positive IgG with compatible history and eosinophilia confirms diagnosis. A 4-fold rise in titre on serial samples confirms active/acute infection. IgG persists for years — cannot distinguish active from old infection without clinical context.
Sensitivity: 80–90% (week 3–5 post-infection); >95% by week 6. Specificity: >95% with ES antigen ELISA. Commercial kits vary in performance. Western blot has higher specificity (>99%) for confirmation of equivocal ELISA results.
Antibodies take 3–5 weeks to develop after Trichinella ingestion. In the first 2 weeks (intestinal phase), serology is usually negative. Testing should be repeated at 3 weeks and again at 5–6 weeks if clinical suspicion remains high and initial results are negative.
Not necessarily. IgG can remain detectable for years after resolved infection. In the context of acute symptoms, eosinophilia, and meat exposure history, a positive serology with rising titres confirms active infection. A static positive IgG alone may indicate past exposure.
No. In typical cases with muscle pain, periorbital oedema, eosinophilia, elevated CK, and positive serology after the relevant exposure, muscle biopsy is not required. Biopsy is reserved for atypical presentations, serology-negative cases, or outbreak investigations requiring species identification.
Serology (ELISA) helps confirm Trichinellosis, which can cause these symptoms:
Explore our medical library for comprehensive parasite diagnostic protocols, treatment guidelines, and clinical reference material.
Describe your symptoms and get a structured AI clinical assessment — possible parasitic causes, recommended tests, and next steps.
Start Free AI Analysis →Content on this page is informed by evidence-based clinical sources including: