A lateral flow assay for the rapid diagnosis of Mycobacterium bovis infection in wild boar

The native Eurasian wild boar (Sus scrofa ) is a reservoir of Mycobacterium bovis , the causative agent of animal tuberculosis (TB), a chronic disease in livestock, companion animals and wild mammals. Cases of M. bovis infection in wild boar or feral pig have been reported worldwide, making early detection a priority in the eradication of the disease. Point‐of‐care diagnostic tests, such as low cost lateral flow assays, provide high specificity and sensitivity and can be performed on site , an essential requirement for a rapid screening of wildlife. A lateral flow assay, LFA, (INgezim TB CROM Ab) for the detection of M. bovis ‐specific antibodies in wild boar serum and blood has been developed based on MPB83, one of the major immunogenic antigens of the bacterium. A total of 140 samples of wild boar serum, well‐characterized by Mycobacterium tuberculosis complex culture and TB compatible post‐mortem lesions, have been analysed with LFA, and results were compared with one in‐house and two commercial Enzyme‐linked Immunosorbent Assays (ELISA), INgezim TB Porcine and INgezim Tuberculosis DR. In experimental samples, the achieved values of sensitivity of the different techniques ranged from 84.3% to 92.1% and the specificity was 100% in all of them. In field animals, specificity ranged from 96% to 100%, whereas sensitivity ranged from 48% to 64% in juvenile wild boar, increasing to 93.3%–100% in adult wild boar. In particular, the total sensitivity and specificity values obtained with the new LFA were 83% and 97%, respectively, indicating that INgezim TB CROM Ab could be used as a first approach for the surveillance of TB in wild boar, with a special applicability for animal‐side testing.Part of this research was funded by the EU, Seventh Research Framework Program FP7‐KBBE‐2013‐7 under grant number nº 613799 (WildTBVac). This is a contribution to the WildDriver grant CGL2017‐89866 from MINECO and EU‐FEDER. We are very grateful to Dr. Mercedes Dominguez and her laboratory (Instituto de Salud Carlos III, Unidad de Inmunología Microbiana, Majadahonda, Spain) for their generous supply of P22 protein complex.Peer reviewe