**Taxonomy of Bunyaviridae : Classification and Characteristics**

Introduction

Bunyaviridae is a family of negative-sense, single-stranded RNA viruses known for their wide host range, including humans, animals, and plants. Understanding the taxonomy of Bunyaviridae is crucial for disease surveillance, prevention, and control.

Classification of Bunyaviridae

The Bunyaviridae family was historically classified into five genera:

Orthobunyavirus –
Phlebovirus –
Nairovirus –
Hantavirus –
Tospovirus –

Reclassification into the Order Bunyavirales

Due to advancements in genomic sequencing and phylogenetic analysis, the International Committee on Taxonomy (ICTV) reclassified Bunyaviridae into the order Bunyavirales in 2017.

This reorganization resulted in multiple families within the order, replacing the original Bunyaviridae classification. The key families now include:

Peribunyaviridae
Phenuiviridae
Nairoviridae
Hantaviridae
Tospoviridae

Genomic and Structural Characteristics

Genome Organization

Bunyaviruses possess a tripartite RNA genome consisting of three segments:

Large (L) segment – Encodes the RNA-dependent RNA polymerase (RdRp).
Medium (M) segment – Encodes glycoproteins (Gn and Gc) responsible for host cell entry.
Small (S) segment – Encodes nucleocapsid proteins and sometimes non-structural proteins.

Virion Structure

Bunyaviruses are enveloped with a roughly spherical morphology (~80–120 nm in diameter).
They have surface glycoproteins facilitating host cell entry.
The genome is encapsidated by nucleoproteins, forming ribonucleoprotein (RNP) complexes.