What Are Rhinoviruses: What to Know and How They Work

What are rhinoviruses? They are the tiny viruses behind most common colds, infecting the lining of the nose and throat and causing sneezing, a runny nose and a sore throat for about a week. There are more than 160 types, which is why adults catch two to four colds a year. Knowing the short answer to “what are rhinoviruses?” helps you care for a cold at home and spot the rare times it needs a doctor.

Key takeaways

• Rhinoviruses cause up to half of all colds and usually stay in the nose and throat.
• Symptoms peak in the first few days, and most colds clear in 7 to 10 days.
• There is no vaccine or antiviral, and antibiotics do not help; rest, fluids and simple pain relief ease symptoms.
• Rhinovirus often sets off asthma flare ups, so follow the plan your doctor gave you.
• Trouble breathing, chest pain or blue lips need urgent care: call 000.

How Rhinovirus Differs From Enterovirus

Rhinoviruses belong to the enterovirus group, but they behave differently from the other enteroviruses. So what are rhinoviruses, set beside their relatives? They grow best at the cooler temperature inside the nose and are destroyed by stomach acid, so they stay in the airways. Other enteroviruses, such as coxsackieviruses and echoviruses, survive stomach acid, multiply in the gut and can spread to the skin, the heart or the lining of the brain.

The symptoms of rhinovirus and enterovirus overlap in the nose and throat, so a doctor cannot always tell them apart. A fever, a rash, mouth ulcers or an upset stomach point more to an enterovirus.

Rhinovirus Symptoms in Adults

Rhinovirus symptoms in adults start one to three days after catching the virus, often with a scratchy or sore throat, then sneezing, a runny nose that turns blocked, a mild cough and tiredness. Fever is mild or absent. The mucus may turn thick and yellow or green after a few days, which is a normal part of a cold and not a sign that antibiotics are needed. People with asthma or chronic lung disease may notice wheeze, chest tightness or more need for their reliever a day or two into a cold.

So what are rhinoviruses like to have? For most adults, a nuisance rather than a danger: the worst days are the second to the fourth, and a dry cough may linger for two or three weeks after the rest has cleared. Symptoms that last beyond ten days, or ease and then return with a fever, deserve a GP's review.

The Viruses Behind the Common Cold

More than 200 different viruses can cause a common cold, and rhinoviruses are the most frequent, behind up to half of colds. The rest come from seasonal coronaviruses, adenoviruses, respiratory syncytial virus, parainfluenza viruses, human metapneumovirus and other enteroviruses, and colds from any of them look much the same.

What are rhinoviruses doing differently to be so common? They come in many types, spread easily on hands, and rarely make people sick enough to stay home, so they pass around offices, schools and households. That is also why a doctor rarely tests to find which virus is behind a cold: the care is the same.

Rhinoviruses, Small Viruses of the Nose Lining

Rhinoviruses are small, simple viruses, a strand of genetic material inside a protein shell, that infect the cells lining the nose. Their name comes from the Greek word for nose. They grow best at about 33 to 35°C, the temperature inside the nose, which is one reason they seldom reach deep into the lungs of healthy people.

Much of the misery of a cold comes from the body's own response, the swelling and mucus as the lining fights the virus, rather than from damage the virus does. That is also why there is no specific treatment for rhinovirus: care eases the symptoms while the immune system clears it.

What Are Rhinoviruses?

Rhinoviruses are members of the picornavirus family, one of the smallest groups of viruses that infect people, and they were first identified in the 1950s. They are split into three species, A, B and C. Rhinovirus C was only recognised in 2006 and is more often linked with severe asthma attacks in children.

Doctors seldom test for them, because the result rarely changes care. When it would help, for example for someone at high risk or in hospital, a nose and throat swab sent to a pathology lab can find rhinovirus as part of a respiratory virus panel. There is no vaccine, largely because there are so many types.

How Rhinoviruses Spread Between People

Rhinoviruses spread mainly by hands: a person with a cold touches their nose, then a door handle or another hand, and the next person touches their own eyes or nose. They also travel in droplets and fine particles from sneezes, coughs and talking, especially in closed rooms.

The virus can survive on hard surfaces for several hours and on hands long enough to pass on. People are most contagious in the first two or three days of symptoms, and can spread it the day before they feel unwell. Washing hands with soap, using a tissue once and binning it, and keeping hands away from the face cut the spread at home and at work. Coughing or sneezing into your elbow, and opening a window in a shared room, help as well.

The Many Rhinovirus Types Behind Repeat Colds

There are more than 160 known types of rhinovirus, and immunity to one gives little protection against the others, so you can catch colds again and again. Each infection leaves antibodies against that type only.

Adults average two to four colds a year, and young children five to ten, which is why parents of young children often catch extra colds. Older adults tend to get fewer, as they have built up immunity to more types over the years. The same variety is why a single vaccine against them all has not been possible.

Rhinovirus Seasons in Australia, Autumn and Spring

Rhinoviruses circulate all year in Australia, with peaks in autumn and spring rather than in the depth of winter. The autumn rise often follows the return to school and work after the summer holidays, as people mix indoors again.

Flu and RSV usually peak in winter, so a cold in March or October is quite likely to be rhinovirus, while a cold in July could be any of them. COVID-19 also comes in waves through the year, so a rapid antigen test is worth doing whenever cold symptoms start, particularly before visiting someone older or unwell.

Treatment for a Rhinovirus Cold at Home

Home care eases the symptoms while your body clears the virus, usually within 7 to 10 days. Rest, drink plenty of fluids, and take paracetamol or ibuprofen for a sore throat or aches if they are safe for you. A saline nasal spray or rinse, steam from a shower, and honey in warm drinks soothe a blocked nose and a cough.

Decongestants from the pharmacy can help for a few days; ask the pharmacist first if you have high blood pressure. Zinc lozenges and vitamin C are widely sold for colds, but the evidence that they shorten one is weak. Antibiotics do not work against viruses and can cause side effects. If you need time off work, a medical certificate can cover the days you are unwell.

Summary

This guide has answered “what are rhinoviruses?”: the viruses behind most colds, how they differ from other enteroviruses, how they spread, why colds keep coming back, and how to ease one at home. If you are still asking “what are rhinoviruses?” because a cold will not shift after ten days or has set off your asthma, a Medio GP can talk it through by phone consult, advise on care, and arrange a swab through a pathology request or an eScript where the doctor thinks it right.

Frequently asked questions

Is the rhinovirus the same thing as a cold?

Not quite the same thing. A cold is the illness, and rhinovirus is the virus that causes it most often, behind up to half of colds. Asking “what are rhinoviruses?” usually leads back to the cold, but which virus causes the common cold in any one case can also be a coronavirus, adenovirus or RSV, and colds from each look alike.

How serious is a rhinovirus infection?

For most healthy adults it is mild and clears in about a week. It can be more serious for people with asthma or chronic lung disease, as it is a leading trigger of flare ups, and for people with a weakened immune system. Call a doctor for rhinovirus symptoms lasting beyond ten days, a high fever, ear or sinus pain, or wheeze; call 000 for severe breathlessness or chest pain.

What is rhinovirus and how do you get it?

Rhinovirus is a small virus that infects the lining of the nose and throat and causes the common cold. You get it from someone else's mucus, picked up on your hands from skin or surfaces and carried to your eyes or nose, or by breathing in droplets. To prevent enterovirus infections and rhinovirus infections, wash your hands often, keep them away from your face and clean shared surfaces.

How long do rhinoviruses last?

A rhinovirus cold usually lasts 7 to 10 days, at its worst on days two to four, though a cough can linger for two or three weeks. When your child has a cold it can last a little longer, and rest and fluids are how most parents treat a child's rhinovirus infection. Call your child's doctor and see them in person if your child is breathing fast, drinking little or unusually drowsy.

Do I need to quarantine if I have rhinovirus?

No, Australia has no quarantine rule for rhinovirus, but staying home for the first few days, while you are most contagious, protects others, especially older or unwell people. Because a cold can look like COVID-19 or flu, a rapid antigen test is worth doing. An enterovirus can also cause respiratory symptoms much like a cold, so symptoms alone do not tell these viruses apart.

Is rhinovirus as bad as RSV?

Usually not. RSV is more likely to cause serious lung infections in babies and older adults, which is why an RSV vaccine is available for older adults, while rhinovirus mostly stays in the nose and throat, though it can trigger asthma attacks. The main difference between rhinovirus and enterovirus is similar: an enterovirus is more dangerous than rhinovirus in rare cases, because it can also reach the heart or the lining of the brain.