Seoul virus is a type of which family of viruses?

• A. New World hantavirus
• B. Old World hantavirus, enveloped RNA
• C. Retrovirus
• D. Coronavirus

Answer: (B)

Seoul virus is a hantavirus, and hantaviruses are classified into Old World and New World groups based on geographic distribution and rodent hosts. Seoul virus is associated with the brown rat and was first described in Asia, placing it in the Old World hantaviruses. Hantaviruses are enveloped, negative-sense, single-stranded RNA viruses with segmented genomes, which distinguishes them from other viral families. This combination—Old World hantavirus and enveloped RNA—best fits Seoul virus, making that choice the correct one.