Validation of a Western Blot for the detection of anti-Trichinella spp. antibodies in domestic pigs

Abstract

Trichinellosis is a zoonotic disease in humans caused by Trichinella spp. According to international regulations and guidelines, serological surveillance can be used to demonstrate the absence of Trichinella spp. in a defined domestic pig population. Most enzyme-linked immunosorbent assay (ELISA) tests presently available do not yield 100% specificity, and therefore, a complementary test is needed to confirm the diagnosis of any initial ELISA seropositivity. The goal of the present study was to evaluate the sensitivity and specificity of a Western Blot assay based on somatic Trichinella spiralis muscle stage (L1) antigen using Bayesian modeling techniques. A total of 295 meat juice and serum samples from pigs negative for Trichinella larvae by artificial digestion, including 74 potentially cross-reactive sera of pigs with other nematode infections, and 93 meat juice samples from pigs infected with Trichinella larvae were included in the study. The diagnostic sensitivity and specificity of the Western Blot were ranged from 95.8% to 96.0% and from 99.5% to 99.6%, respectively. A sensitivity analysis showed that the model outcomes were hardly influenced by changes in the prior distributions, providing a high confidence in the outcomes of the models. This validation study demonstrated that the Western Blot is a suitable method to confirm samples that reacted positively in an initial ELISA.

Trichinella sp. in red foxes (Vulpes vulpes) from Catalonia, NE Spain

“…Although serological ELISA test have been developed (Kořínková et al 2006 and2008;Frey et al 2009), and they seem to have a higher sensitivity (Jakob et al 1994;Wacker et al 1999), the digestion method used in the present study is the official method approved by the European Union (European Community 2005).…”

Seroprevalence of trichinellosis in domestic animals in northwestern Vietnam

“…The enzyme linked immunosorbent assay (ELISA) using excretory-secretory (ES) antigens, prepared from the first stage larvae of T. spiralis was used as a screening tool and confirmatory testing was done by Western blot (WB) using the same ES antigens, in order to exclude false positive results (Yera et al, 2003;Nöckler and Kapel, 2007;Frey et al, 2009;Moskwa et al, 2009;Nöckler et al, 2009). …”

Comparing the demonstration of freedom fromTrichinellainfection of domestic pigs by traditional and risk-based surveillance

“…8-99 . 9% [18,20]. In case antibodies were demonstrated by WB, investigations should be initiated on the farm of origin to assess the opportunities for exposure of pigs to Trichinella spp.…”