Sensitivity of specimen type for diagnosing foot-and-mouth diseases in cattle using one-step real-time polymerase chain reaction (3D gene).

Background: Indonesia is currently experiencing a foot-and-mouth disease (FMD) outbreak in livestock, caused by the FMD virus (FMDV). FMDV is easily spread to cause outbreaks in new geographical locations. Identifying FMDV infection through early diagnostic testing is important to track and prevent the spread of FMD in Indonesia. The use of appropriate samples is a crucial step in a study or survey to provide accurate results for diagnosis.

Aim: The aim of our study was to evaluate the sensitivity of relevant oral mucosal epithelial swabs, hypersalivation swabs, and blood plasma specimen samples for FMDV diagnosis using one-step real time PCR (3D).

Methods: Sampling was carried out by judgment or purposive, namely selecting animals that showed symptoms of the disease. A total of 109 samples were collected consisting of 3 types of oral mucosal epithelial swab specimens, hypersalivation swabs, and blood plasma collected from each cow reported as suspected FMDs in 8 districts in South Sulawesi were tested for FMDV using one-step RT-PCR (3D).

Results: FMDV infection in oral mucosal epithelial swabs (ct = 28.9), saliva (ct = 30.62), and blood plasma (ct = 37.17) compared to controls used from the Farma Veterinary Center (ct = 29.10) using RT PCR (3D gene). These results indicate that the sensitivity value of oral mucosal epithelial swab specimens is the same as positive controls, even more sensitive, than when compared to saliva or blood plasma specimens. Sensitivity depends on the cycle threshold (CT) value for each RT PCR test and should be preferred in crucial situations if possible.

Conclusion: These findings indicate that using oral mucosal epithelial swab specimens is more sensitive to be used as superior samples for FMDV detection using RT-PCR (3D) as a powerful tool for early detection to enable faster and effective treatment.