Development of recombinant nonstructural 1 protein based indirect enzyme linked immunosorbent assay for sero-surveillance of Japanese encephalitis in swine

• Published in: Journal of virological methods Vol. 272; p. 113705
• Main Authors: Dhanze, H., Bhilegaonkar, K.N., Rawat, S., Chethan Kumar, H.B., Kumar, A., Gulati, B.R., Mishra, B.P., Singh, R.K.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-10-2019
• Subjects: Animals; ELISA; Encephalitis Virus, Japanese - genetics; Encephalitis Virus, Japanese - isolation & purification; Encephalitis, Japanese - diagnosis; Encephalitis, Japanese - immunology; Encephalitis, Japanese - veterinary; Encephalitis, Japanese - virology; Enzyme-Linked Immunosorbent Assay - methods; Enzyme-Linked Immunosorbent Assay - veterinary; Immunoglobulin G; India; Japanese encephalitis; Neutralization Tests - methods; Recombinant Proteins - genetics; Recombinant Proteins - immunology; Surveillance; Swine; Swine Diseases - diagnosis; Swine Diseases - virology; Viral Nonstructural Proteins - genetics; Viral Nonstructural Proteins - immunology; India; Surveillance; Swine; ELISA; Japanese encephalitis
• ISSN: 0166-0934; 1879-0984
• DOI: 10.1016/j.jviromet.2019.113705

•An indirect ELISA using recombinant NS1 protein to detect anti-JEV IgG antibody in swine.•Developed ELISA validated in 10 different laboratories revealing excellent reproducibility.•Screening of 3628 swine Serum samples revealed sero-positivity of 32.22% against JE virus.•Developed ELISA can be used in surveillance programs for detection of JEV activity in swine population thereby aiding in prevention of outbreaks in humans.
Japanese encephalitis virus (JEV) causes severe neurological disease in humans, especially among children. The disease is endemic in several South Asian countries including India. Swine play a major role as amplifier host for JEV and act as a source of infection to humans through mosquito bite. Early detection of either virus or antibodies in swine will aid to undertake control measures to prevent virus spread to humans. Swine seldom show symptoms of JEV infection and the viraemic phase lasts for a short period of 3 to 4 days indicating the potential of detection of antibodies, which remain for relatively longer period, as a suitable alternative. Cost effective and sensitive assays for the detection of JEV antibodies in swine are not available indigenously. Hence, we have developed a recombinant nonstructural protein 1 (rNS1) based enzyme linked immunosorbent assay for the detection of IgG antibodies against JEV in swine. The test is robust, highly sensitive (91%), specific (97%), reproducible and affordable. Field validation of the assay was done by screening 3628 swine Serum samples collected from different parts of India. The overall sero-positivity was found to be 32.22%. The developed ELISA can be readily incorporated into surveillance programs for detection of Japanese encephalitis virus activity in swine population thereby aiding in prediction of outbreaks in humans.