Written by Ada’s Medical Knowledge Team
What is a common cold?
A common cold is a mild viral infection of the nose, throat, sinuses and upper airways. It is one of the most frequently experienced acute illnesses in the United States and throughout the industrialized world. Adults will develop roughly two to three colds per year.
The symptoms of a cold include coughing, sneezing, a sore throat and a runny or blocked nose. In most cases, a person experiencing a cold will have no need to visit a doctor, as the symptoms will typically clear up on their own in up to 10 days. Management techniques for the common cold include methods such as rest and hydration.
Common cold symptoms
The symptoms of a cold tend to develop quickly, usually within a few days of an individual becoming infected.
The most commonly experienced symptoms of a cold include:
- A sore throat
- A runny or blocked nose
- A hoarse voice
- Malaise ( a feeling of general discomfort and illness, which should to be confused with general fatigue)
Less common symptoms of a cold include:
- Fever (37-39 C / 98.6-102.2 F)
- A feeling of pressure in the ears and face
- Muscle pain
The symptoms of a cold will usually begin to fade within a few days and clear up completely after roughly a week to 10 days. Colds will generally last longer (10-14 days) in children under five years old.
When to see a doctor?
In most cases, a cold will not require visiting a doctor. However, medical attention should be sought in the following cases:
- Symptoms do not disappear after three-weeks
- Symptoms suddenly worsen
- Breathing becomes difficult
Common cold causes
There is a large range of viruses that can cause a cold. Most colds are caused by a group of viruses known as rhinoviruses, of which there are over a 100 different types.
After having a cold, the affected person becomes immune to that particular virus strain. However, due to the large amount of cold-causing viruses, many people still experience an average of two to three colds per year. As children tend to spend a large amount of time in close contact with other children and are less aware of the methods of preventing a cold, they are prone to experiencing an average of 8-12 colds per year.
Colds are normally spread through hand-to-hand contact and less commonly through coughing, sneezing or touching a surface that has been exposed to the virus.
Diagnosing a common cold
Most people will be able to self-diagnose a cold by recognizing the symptoms being experienced. This will also be the case if a doctor is consulted, though this will not be necessary in most cases. If a complication is suspected, various tests may be ordered (such as an X-ray). If you think your symptoms may be those of the common cold, you can check by doing a free symptom assessment with the Ada app at any time.
Common cold treatment
A cold will typically remedy itself in up to 10 days. During this time, the symptoms of a cold can be managed through a combination of self-care techniques and over-the-counter medications. These methods, however, will not shorten the duration of the cold.
To help manage the symptoms of a cold, the following things may be effective:
- Adequate fluid intake
- Getting plenty of rest
- Eating healthily; a diet high in fibre, fruit and vegetables is recommended
- Stopping smoking
The following medications are generally available from a pharmacy without requiring a prescription. The information leaflet that accompanies the product should always be read before use and their guidelines should be followed.
- Painkillers: Ibuprofen and paracetamol/acetaminophen may be effective for the relief of a fever and as general pain relief. Children may be given painkillers, though age-appropriate versions (usually available from pharmacies) are generally advised. Children should never be given paracetamol and ibuprofen at the same time. Some people prefer to use non-steroidal anti-inflammatory (NSAIDs) medications such as aspirin to help relieve the symptoms of a cold. Under no circumstances should a child 12 years or younger be given these medications.
- Decongestants: Oral or spray decongestants may be effective in relieving a runny or blocked nose and help ease breathing problems. They should not be taken by children under 6, and only on the advise of a doctor in children under 12. The effects of decongestants only last for a short period and should not be used for over a week.
- Cold medicines: All-in-one cold medicines generally include a combination of painkillers and decongestants, making them effective at relieving a variety of cold symptoms. Generally, these medicines should not be taken in combination with any other medication.
- Lozenges: Oral lozenges help to lubricate the lining of the throat, making them effective at relieving a sore throat.
- Vapor rubs: Applied to the chest and back, vapor rubs can help a child breathe more easily. Although less commonly used, they may also be effective for adults.
Common cold complications
In the majority of cases, a cold will clear up without complications. However, a cold can lead to a weakened immune system, which can cause infection to spread into other areas. If this occurs, the following complications are possible.
One of the more frequently experienced complications of a cold, occuring in roughly 1 in 50 people, sinusitis is an infection of the cavities behind the forehead and cheekbones, typically caused by a virus. It is also possible to have bacterial sinusitis.
Symptoms of sinusitis include:
- Sinus headaches (pain and tenderness around the forehead, nose and cheeks)
- Runny or blocked nose
- Fever (above 38 C / 100.4 F)
Sinusitis will usually resolve itself. If symptoms persist for longer than a week, a doctor should be consulted. If you think that you or someone you know has sinusitis, you can check symptoms using the free Ada app at any time.
Middle ear infection
The development of a middle ear infection (otitis media) following a cold is most common in children. It is typically caused by bacterial infection.
Signs and symptoms of a middle ear infection include:
- Pain in the ear (earache) (parents should look out for children pulling or tugging on the ear)
- Fever (above 38 C / 100.4 F)
- Temporary hearing loss
A middle ear infection will generally clear up naturally within a few days. If symptoms persist for longer than a few days or repeated infections are experienced, a doctor should be consulted. If you're worried that you or a child you care for may have an ear infection, you can do a free symptom assessment using the Ada app at any time.
Typical symptoms of a chest infection include:
- Bringing up phlegm
- Shortness of breath
Generally, a chest infection will resolve naturally. If the following symptoms occur, a doctor should be consulted, as they may indicate that a bacterial infection, requiring antibiotics, is being experienced:
- Severe cough
- High temperature
- Confusion or disorientation
- Pain in the chest
- Blood in the phlegm
- Symptoms last for longer than three weeks
If you are concerned that you or someone you know may have a chest infection, you can do a symptom assessment at any time using the free Ada app.
Common cold prevention
The viruses that cause colds are typically spread through the tiny droplets released when someone with a cold coughs or sneezes. This may happen when a person inhales these droplets after they have been released into the air, or, more typically, through skin-to-skin contact with an infected person (droplets are most likely to be present on the hands) or through contact with a contaminated surface or object.
To help prevent the development of a cold, the following measures are advised:
- Keeping the hands clean by washing them often with soap and water
- Avoiding unnecessary touching of the eyes, nose and mouth
- Staying away from people with a cold
People who already have a cold should avoid spreading the virus by taking the following steps:
- Staying home from work or school
- Avoiding close contact with others (shaking hands, kissing, etc)
- Completely covering the mouth and nose when coughing or sneezing
- Washing the hands after coughing or sneezing
Common cold FAQs
Q: Do I have a common cold or flu?
A: Although the common cold shares symptoms with flu, it is, in fact, a far more serious condition and not merely a severe cold. As with a cold, a person with flu may experience symptoms such as coughing, sneezing and a sore throat, but they are also much more likely to experience fever, fatigue and muscle aches. Flu symptoms also typically appear more suddenly and disappear after around a week. If symptoms persist for longer than this or are particularly severe, medical attention should be sought. If you are not sure whether you have a cold or flu, you can do a free symptom assessment using the Ada app at any time.
Q: Is there a cure for the common cold?
A: No, there is currently no cure for the common cold. However, a cold will in most cases disappear naturally and its symptoms can be managed through a combination of self-care (drinking fluids, resting, etc) and medication (painkillers, decongestants, etc). As a cold is viral in nature, antibiotics are ineffective.
Q: What is the typical duration of a common cold?
A: In adults, colds tend to last for an average of 7 to 10 days. Children may have a cold for slightly longer, with it normally lasting for up to two weeks. If a cold persists for over three weeks, medical attention should be sought.
Q: What is the incubation period for a common cold?
A: The typical incubation period for a cold is 24 to 72 hours. After this, symptoms will begin to develop.
UpToDate. “Patient education: The common cold in adults (Beyond the Basics).” March 1, 2016. Accessed December 4, 2017. ↩