|Pacheco Tobin, Juan|
|BRITO, BARBARA - University Of California|
|PEREZ, ANDRES - University Of Minnesota|
Submitted to: Transboundary and Emerging Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/17/2015
Publication Date: 8/25/2015
Publication URL: http://handle.nal.usda.gov/10113/61602
Citation: Pacheco Tobin, J., Brito, B., Hartwig, E.J., Smoliga, G.R., Perez, A., Arzt, J., Rodriguez, L.L. 2015. Early detection of foot-and-mouth disease virus from infected cattle using a dry filter air sampling system. Transboundary and Emerging Diseases. doi: 10.1111/tbed.12404.
Interpretive Summary: Foot-and-mouth disease (FMD) is a highly contagious viral disease of cattle, pigs, sheep, goats, and wild cloven-hoofed animals. The disease is characterized by fever and vesicular lesions in the mouth, tongue, feet, and teats. Due to significant losses associated to decreased production and impact on international trade of animal and animal products, FMD has a high economic impact. Early detection of FMD virus (FMDV) is fundamental for rapid control. Since FMDV is transmitted through the air, collection of air samples in the proximity of potentially sick animals can be a useful tool for early detection. The current study investigated FMDV detection in animal containment rooms housing one to four steers. Air detection was compared with virus detection in serum and saliva, as well as with clinical signs. Virus was detected as early as 3 days before clinical signs and as early as 2 days before detection in saliva. These data confirm that air sampling is an effective, non-invasive screening method for detecting FMDV in enclosed spaces. This technology could be used for early detection of FMD infection in places where animals congregate such auctions barns, milking parlors and slaughter houses. This technology could be a useful tool as part of a surveillance strategy during FMD prevention, control or eradication efforts.
Technical Abstract: Foot-and-mouth disease (FMD) is a highly contagious livestock disease of high economic impact. Early detection of FMD virus (FMDV) is fundamental for rapid outbreak control. Air sampling collection has been demonstrated as a useful technique for detection of FMDV RNA in infected animals, related to the aerogenous nature of the virus. In the current study, air from rooms housing individual (n=17) or two groups (n=4) of cattle experimentally infected with FDMV A24 Cruzeiro of different virulence levels was sampled to assess the feasibility of applying air sampling as a non-invasive, screening tool to identify sources of FMDV infection. Detection of FMDV RNA in air was compared with first detection of clinical signs and FMDV RNA levels in serum and oral fluid. FMDV RNA was detected in room air samples 1-3 days prior (7 animals) or on the same day (4 animals) as the appearance of clinical signs in 11 out of 12 individually housed cattle. Only in one case clinical signs preceded detection in air samples by one day. Overall, viral RNA in oral fluid or serum preceded detection in air samples by 1-2 days. Six individually housed animals inoculated with attenuated strains did not show clinical signs but virus was detected in air in one of these cases 3 days prior to first detection in oral fluid. In groups of 4 cattle housed together, air detection always preceded appearance of clinical signs by 1-2 days and coincided more often with viral shedding in oral fluid than virus in blood. These data confirm that air sampling is an effective noninvasive screening method for detecting FMDV infection in confined to enclosed spaces (e.g. auction barns, milking parlors). This technology could be a useful tool as part of a surveillance strategy during FMD prevention, control or eradication efforts.