EU-approved rapid tests might underestimate bovine spongiform encephalopathy infection in goats. (March 2017)

• Record Type: Journal Article
• Authors: Meloni, Daniela; Bozzetta, Elena; Langeveld, Jan P. M.; Groschup, Martin H.; Goldmann, Wilfred; Andrèoletti, Olivier; Lantier, Isabelle; Van Keulen, Lucien; Bossers, Alex; Pitardi, Danilo; Nonno, Romolo; Sklaviadis, Theodoros; Ingravalle, Francesco; Peletto, Simone; Colussi, Silvia; Acutis, Pier Luigi
• Is Part Of: Journal of veterinary diagnostic investigation. Volume 29:Number 2(2017:Mar.)
• Page Start: 232
• Page End: 236
• Publication Date: 2017-03
• Subjects: Bovine spongiform encephalopathy -- diagnosis -- EU -- goats -- rapid tests -- scrapie -- sensitivity -- surveillance; Veterinary medicine -- Diagnosis -- Periodicals; 636.0896075
• DOI: 10.1177/1040638716688045
• Languages: English
• ISSNs: 1040-6387

Abstract

We report the diagnostic sensitivity of 3 EU-approved rapid tests (ELISAs; 1 from IDEXX and 2 from Bio-Rad) for the detection of transmissible spongiform encephalopathy diseases in goats. Ninety-eight goat brainstem samples were tested. All the rapid tests had 100% specificity and ≥80% sensitivity, with the IDEXX test significantly more sensitive than the 2 Bio-Rad tests. All tests detected 100% of samples from goats with clinical scrapie, but missed 8% (IDEXX) to 33% (Bio-Rad SG) of samples from preclinical goats. Importantly, only IDEXX picked up all samples from clinical bovine spongiform encephalopathy (BSE)-infected goats, whereas the other 2 rapid tests missed 15% (Bio-Rad SG) to 25% (Bio-Rad SAP). These results show that a fraction of preclinical scrapie infections are likely missed by EU surveillance, with sensitivity of detection strongly dependent on the choice of the rapid test. Moreover, a significant proportion of clinical BSE infections are underestimated by using either Bio-Rad test. Assuming that the same sensitivity on preclinical goats would also occur in BSE-infected goats, our data suggest that IDEXX is likely the most sensitive test for detecting preclinical field cases of BSE infection in goats, although with an 8% failure rate. These results raise some concerns about the reliability of current EU surveillance figures on BSE infection in goats.