The human rhinovirus is the primary cause of what is commonly known as the common cold. These viruses are widespread and responsible for more than half of all cold-like illnesses. While often causing mild and self-limiting infections, rhinoviruses can still lead to considerable discomfort and missed days from work or school.
Understanding the Rhinovirus
Rhinoviruses belong to the Picornaviridae family and are classified within the Enterovirus genus. These are small, non-enveloped RNA viruses, specifically positive-sense, single-stranded RNA viruses. The viral genome directs the production of proteins that form the outer shell, or capsid, that encases the genetic material.
The diversity among rhinoviruses contributes to their prevalence, with over 100 different strains or serotypes identified. More recently, a third species, HRV-C, was discovered, which can also cause respiratory infections, sometimes more severe, especially in children. Rhinoviruses thrive and replicate best at temperatures between 33°C and 35°C, which limits their activity primarily to the cooler upper respiratory tract, including the nose and throat.
Common Symptoms
A rhinovirus infection manifests with familiar symptoms affecting the upper respiratory system. These often begin one to three days after exposure and can include a runny or stuffy nose, sneezing, and a sore throat. Cough and mild headache are also common. The nasal discharge may start clear and later become thicker, appearing gray, yellow, or green.
Symptoms can overlap with other respiratory illnesses, but rhinovirus infections are milder compared to the flu or COVID-19. Fevers are less common in adults with a cold but may be present in children. Unlike the flu, which often has a sudden onset of severe symptoms, or COVID-19, which can cause loss of taste or smell, cold symptoms tend to be less intense and localized. Most individuals recover within 7 to 10 days, though some colds can persist for up to two weeks.
How It Spreads and Prevention
Rhinoviruses primarily spread through direct contact with respiratory droplets expelled when an infected person talks, sneezes, or coughs. Transmission can also occur indirectly through contaminated surfaces, known as fomites. Rhinoviruses exhibit moderate resistance to common disinfectants, including alcohol-based hand rubs.
Preventing the spread involves frequent and thorough handwashing with soap and water. Avoiding touching the face, particularly the eyes, nose, and mouth, can prevent the virus from entering the body. Covering coughs and sneezes with a tissue or the elbow helps contain respiratory droplets. No vaccine is currently available to prevent rhinovirus infection due to the large number of circulating serotypes.
Managing the Illness
Managing a rhinovirus infection focuses on relieving symptoms and supporting the body’s natural recovery process. Rest is recommended, along with maintaining good hydration by drinking plenty of fluids. Over-the-counter medications can help alleviate discomfort. Pain relievers such as acetaminophen or ibuprofen can reduce headaches and mild body aches, and may help lower a fever.
Nasal decongestants, available as sprays or tablets, can help clear a stuffy nose, while antihistamines may reduce sneezing and a runny nose. Cough suppressants can also be used for cough relief, though their use in children under six years old should be supervised by a healthcare provider. Using a humidifier can soothe irritated nasal passages and help clear secretions.
Most rhinovirus infections are mild and resolve on their own. It is advisable to consult a doctor if symptoms worsen, a high fever develops, or if there is difficulty breathing. For infants, a doctor should be consulted if cold symptoms appear, especially if they are three months old or younger, as they are more susceptible to severe complications.