1Department of Veterinary Clinical Medicine, College of Veterinary Science and Animal Husbandry, OUAT, Bhubaneswar, Odisha, India
2ICAR-International Centre for Foot-and-Mouth Disease - DFMD, Arugul, Bhubaneswar, Odisha, India
3Department of Veterinary Pathology, College of Veterinary Science and Animal Husbandry, OUAT, Bhubaneswar, Odisha, India
4Division of Animal Genetics and Breeding, ICAR-National Dairy Research Institute, Karnal, Haryana, India
5Kamal Nehru Womens College, Bhubaneswar, Odisha, India
*Corresponding author: RC Patra; E-mail: rcpatra@gmail.com
Online Published on 19 July, 2023.
Approximately, 50% of Foot and Mouth Disease (FMD) affected bovines persistently harbours the virus in the oro-pharyngeal epithelium for a prolonged period of time after recovery. The phenomenon is known as FMDV persistence and the animals as FMDV carriers. The virus can be isolated from oropharyngeal fluid (OPF) during a period more than 28 days after infection. Although direct transmission of virus from carrier to healthy animals has not been established, but these animals as a risk, for emergence of new outbreak cannot be overlooked. Therefore, trade policies consider the carriers as contagious and import of livestock from enzootic zones is restricted. FMDV persistence also complicates the retrieval of FMD-free status as the country or zone must evidence complete clearance of virus source. Thus, the detection of carrier animals after an outbreak or during export and import is essentially needed. This can be achieved by detecting the viral antigen and genome, or viral antibodies. Various methods such as virus isolation, RT-PCR, mucosal antibody detection ELISA etc. have been developed for this purpose. However, each test has some advantages and limitations. This article discusses about the persistence of FMDV in carrier animals and various methods for its detection.
• The article describes the FMDV persistence in carrier animals and various methods for its detection.
• About half of the FMD affected bovines persistently harbours the virus in the oro-pharyngeal epithelium for a prolonged period after recovery.
• The diagnosis of carrier animals after an outbreak can be achieved by detecting the viral antigen genome.
Foot-and-Mouth Disease, Carrier, Oropharyngeal fluid, ELISA, RT-PCR
