Which test is used to diagnose senecavirus A?

• A. Serum neutralization test
• B. Clinical signs
• C. RT-PCR
• D. ELISA test

Answer: (C)

The test being used here is designed to detect the virus’s genetic material directly, which is the most reliable way to confirm an active Senecavirus A infection. Senecavirus A is an RNA virus, so a reverse transcription step converts its RNA into DNA and then PCR amplifies specific viral sequences. This makes RT-PCR highly sensitive and specific for diagnosing infection in the animal stressed by vesicular disease.

Clinical signs alone aren’t enough because many diseases can cause similar vesicular lesions, so you need a test that confirms the presence of the virus itself. Serology options like ELISA or serum neutralization detect antibodies, indicating exposure or immune response rather than an active infection; they may be negative early in illness or positive due to past exposure. Therefore, they’re less suitable for diagnosing an acute case.

So RT-PCR is the best choice for diagnosing Senecavirus A, especially in the early phase when rapid and direct evidence of viral RNA is needed.