Question

Influenza viruses are RNA viruses and belong to which family:

• A. Orthomyxoviridae
• B. Papoviridae
• C. Retroviridae
• D. Parvoviridae

Answer 1

The Correct Option is A

The correct option is (A): Orthomyxoviridae.

Answer 2

The question asks which family influenza viruses, RNA viruses, belong to. A useful way to sort this out is by comparing genome type and structure across the options.

1. Orthomyxoviridae: Viruses in this family carry a segmented, single-stranded, negative-sense RNA genome split into eight separate pieces. This segmentation allows different influenza strains to swap gene segments when they infect the same cell, a process called reassortment, which is a defining and well-known feature of influenza viruses.
2. Papoviridae: Viruses in this family, such as papillomavirus, carry a double-stranded, circular DNA genome, a completely different genetic material from influenza's RNA, and they cause warts and certain tumors rather than respiratory illness.
3. Retroviridae: These are single-stranded RNA viruses, but they carry the enzyme reverse transcriptase and copy their RNA into DNA once inside a host cell, as HIV does. Influenza never converts its genome into DNA, so it does not fit this family despite both being RNA viruses.
4. Parvoviridae: These are very small viruses with a single-stranded DNA genome, causing diseases such as erythema infectiosum. Their DNA genome rules them out entirely for an RNA virus like influenza.

The segmented, negative-sense RNA genome and the ability to reassort gene segments are hallmark features specific to Orthomyxoviridae, matching influenza viruses exactly.

Therefore, the correct answer is Orthomyxoviridae.