Which virus family consists of segmented genomes and includes the influenza virus?

• A. Orthomyxoviruses
• B. Picornaviruses
• C. Arenaviruses
• D. Reoviruses

Answer: (A)

Segmentation of the genome is a hallmark of the Orthomyxoviridae family, which includes influenza viruses. These viruses have a segmented, negative-sense, single-stranded RNA genome stored in eight separate segments inside an enveloped virion. This segmentation allows genetic reassortment when different strains infect the same cell, fueling rapid antigenic change (antigenic shift). Other options either have nonsegmented genomes (picornaviruses), or have segmented genomes of a different type (reoviruses with double-stranded RNA), or belong to a different family with a somewhat similar feature but not influenza. Since influenza belongs to Orthomyxoviridae and shares the segmented genome trait, this family is the correct one.