Rhinovirus: biology, symptoms, transmission and prevention

Virology and structure

Rhinoviruses belong to the Picornaviridae family and are small, non-enveloped viruses with a single-stranded positive-sense RNA genome. The viral particle is roughly 30 nm in diameter, giving it a compact icosahedral capsid composed of structural proteins. Their capsid proteins determine antigenic types; historically many distinct serotypes were recognized, and modern classifications group human rhinoviruses into several species (commonly called A, B and C). For notes on the anatomy of the upper airway that rhinoviruses target, see the upper respiratory tract and for the relationship to throat infection see the pharynx and throat.

Symptoms, course and transmission

Rhinovirus infection usually produces symptoms that are localized to the nose and throat: sneezing, nasal congestion or runny nose, sore throat, mild cough, and general malaise. Fever is uncommon in healthy adults but can occur in children. The incubation period is typically short (about one to three days), and viral shedding is greatest early in the illness. Transmission occurs by respiratory droplets, direct person-to-person contact and contaminated surfaces (fomites); hand-to-face contact after touching contaminated surfaces is a common route.

Epidemiology and clinical importance

Rhinoviruses circulate year-round but often peak in temperate climates during spring and autumn. Children experience colds more frequently than adults, and rhinoviral infections are a leading trigger of wheezing episodes, asthma exacerbations and flare-ups of chronic obstructive pulmonary disease (COPD). Although most infections are self-limited, complications such as sinusitis, otitis media in children, and lower respiratory involvement in vulnerable people can occur.

Diagnosis, treatment and prevention

Routine diagnosis is usually clinical; specialized laboratory tests such as PCR or viral culture are used in research or when confirmation affects management. There is no widely used specific antiviral therapy or vaccine because antigenic diversity and many serotypes complicate vaccine development. Management focuses on symptomatic relief: fluids, rest, analgesics, saline nasal irrigation and, when appropriate, decongestants. Antibiotics are not indicated for uncomplicated viral colds. Good hygiene—frequent handwashing, avoiding close contact with symptomatic people, and cleaning commonly touched surfaces—reduces transmission.

Notable facts and historical notes

Rhinoviruses were first distinguished as causes of colds in the mid-20th century and have been studied as a model for virus-host interaction in the upper airway. Their small size (about 30 nm) and rapid replication at the relatively cool temperatures of the nasal passages (approximately 33–35 °C) explain why the nose is a favored site for infection. Laboratory study of rhinoviruses uses techniques from molecular virology and electron microscopy; see electron microscopy references at capsid and particle studies. Continued research seeks better antiviral agents and ways to prevent virus-induced exacerbations of chronic respiratory disease.

• Common signs: sneezing, rhinorrhea, sore throat.
• Transmission: droplets, direct contact, fomites.
• Prevention: hand hygiene and surface cleaning.