Common cold, respiratory tract infection

The common cold is the most frequent human ailment. It is a viral disease that heals by itself. Its symptoms last on average 10 days, with or without medication. In a third of all patients, the usual symptoms of the common cold (without complications that require treatment) last for nearly three weeks. It is sensible to use over-the-counter medicines to treat the symptoms, including pain, fever and nasal congestion.

Adults suffer an average of 2 to 4 respiratory tract infections a year, mainly during autumn, winter and spring. A respiratory tract infection can be caused by any of over 200 viruses. Rhinoviruses cause about half of all cases of the common cold and, in September-October, as many as 90 per cent of respiratory tract infections in adults. The viral group is of no consequence in the care of a cold patient - the treatment practice and further measures are the same, irrespective of the cause: the basic treatment consists of rest, plenty of drink and vapour inhalation therapy to relieve the symptoms, an anti-inflammatory analgesic to treat possible fever and pain, and a nasal spray to ease congestion.

Cold viruses spread easily through the air at close range and in direct contact through people or inanimate objects and surfaces. For example, having just blown his nose, a cold patient touches a doorknob or a phone, and the person who touches it next gets the virus through his hands into his nose, mouth etc. The incubation period of the common cold is usually one or two days, and nasal discharge may contain contagious viruses even two or three weeks after the onset of the disease.

Symptoms of the common cold include sore throat, runny nose, cough and a sensation of pressure in the forehead and cheeks. The common cold in adults is mostly feverless. Symptoms may vary depending on the specific virus, but the pattern of the most common pathogen, the rhinovirus, is typical: the disease begins with a sore throat, which is the predominant symptom during the first few days. Nasal symptoms - runny nose, congestion, sensation of pressure - gradually worsen, and cough occurs around the fourth or fifth day. Within a rough week, the symptoms clearly lessen and the worst stage of the disease is over. Cough symptoms may persist over several weeks after the cold. During a cold, symptoms around the maxillary sinuses are frequent, including a sensation of pressure in the cheeks and above the eyes. These are symptomatic of an infection caused by the virus in the mucous membrane of the sinus and will heal by themselves within three weeks in well over 90 per cent of patients. Antibiotics cannot be used to treat these symptoms or to speed up recovery. Less than one per cent of adults develop a post-cold maxillary sinusitis of bacterial origin. Bacterial sinusitis is a possibility to consider if the sinus symptoms last for over 10 days without gradually withdrawing or if the pattern of symptoms includes distinct aching and soreness in the upper teeth. There are no exact figures on the prevalence of bacterial infections of the lower respiratory tract (the lungs and bronchi) as post-cold complications, but they are relatively uncommon in adults. Asthma patients typically experience a worsening of their symptoms as a result of a viral infection in the respiratory tract and need to increase or resume their asthma medication for the duration of the cold. Pain radiating to the ears is often associated with the sore throat symptoms of the cold, but a bacterial middle ear infection (requiring antibiotic treatment) is a rare post-cold complication among adults.

When to consult a nurse or doctor?   

The common cold heals by itself, and a nurse or doctor has no means of treatment beyond home care and over-the-counter products. The primary treatment for the cold is rest. Sports and exercise must be avoided when ill. You may consult a nurse if your employer demands a medical certificate for your absence.

If you experience any of these symptoms, you should consult a doctor:

  • high fever (38 °C) for over 3 to 5 days (or if fever recurs following a period of normal temperature) 
  • fever combined with violent or continuous coughing 
  • intense pain while breathing 
  • violent headache 
  • altered consciousness
  • cold symptoms persisting for several weeks and accompanied by one or more signs of complications described in the previous paragraph.

Sore throat, throat infection, tonsillitis ("angina")

Throat infection, or sore throat, is a common ailment that, in most cases, requires either no treatment at all or no more than symptom-relieving treatment and medication. If a throat culture determines the cause of throat infection to be a bacterium, especially a group A streptococcus, antibiotic medication is required. It will prevent complications from arising and stop the disease from spreading.

Throat infection caused by viruses in the upper respiratory tract

Viral infections of the upper respiratory tract are characterised by a sore throat and pain while swallowing. A multitude of symptoms is typical of viral infections: cough, runny nose, sore throat and elevated temperature. The throat may be red and the tonsils may show signs of coating. Throat infection associated with the common cold is treated with plenty of drink and, if needed, a painkiller (an over-the-counter anti-inflammatory analgesic).

Throat infection caused by a group A streptococcus, or tonsillitis ("angina")  

Throat infection caused by a streptococcus cannot be identified by its symptoms alone; the diagnosis must be based on throat cultures. The cause of throat infection may be a bacterium if the sore throat is sudden and accompanied by a rise in temperature (usually to over 38 °C), but by no other typical symptom of an upper respiratory tract infection (i.e. the common cold). In conjunction with tonsillitis, white coating may be visible in the tonsils and throat. Tonsillitis is also suspected if someone in the patient's immediate family has recently had tonsillitis or people at the patient's school or college, workplace, day-care centre etc. are suffering from tonsillitis. Untreated, tonsillitis may cause an epidemic. Tonsillitis verified by laboratory tests is treated with antibiotic medication (primarily penicillin) and the associated sore throat with anti-inflammatory analgesics. It is possible to start treating the pain even before the laboratory tests results are available. This will have no effect on the efficacy of the antibiotic treatment.

Throat infection caused by mononucleosis  

Infectious mononucleosis ("kissing disease", or glandular fever) is a viral disease, symptomised in teenagers and young adults by throat infection, swelling of lymph nodes (especially in the neck) and high fever and, less frequently, hepatitis. In small children, the symptoms are milder. Mononucleosis needs mucous membrane contact to be contagious - hence the title kissing disease. In its early stages, mononucleosis is easily mistaken for tonsillitis - the throat is swollen and often coated. Mononucleosis is identified in a laboratory test, showing a blood count typical of the disease. The symptoms of mononucleosis last for a long time - typically 7 to 12 days - and there is no specific medication for it. You can only have mononucleosis once in your life.

When to consult a nurse or doctor about sore throat?

If you experience any of the following symptoms, you should consult a doctor:

  • sore throat is abnormally painful and accompanied by fever (over 37.5 °C) but not by the other symptoms of the common cold (you may well wait at home for 2 to 3 days to see if they arise) 
  • sore throat makes swallowing liquids much more difficult 
  • sore throat persists for over 7 to 10 days 
  • while a confirmed case of tonsillitis is being treated with medication, the throat becomes extremely sore and/or the soreness recurs 
  • a confirmed case of tonsillitis was successfully treated with medication, and the soreness immediately recurs.


Influenza viruses cause epidemics each year, peaking in midwinter and early spring. The clinical picture of influenza varies, but only a minority of cases are severe. The magnitude of the epidemic also varies yearly. The disease may be perilous to the elderly and to patients suffering from a chronic pulmonary, cardiac or vascular disease.

The symptoms of influenza differ from those of the common cold - influenza is normally accompanied by high fever (over 38 °C) over a period of several days. Sore muscles, headache, general weariness and malaise are typical. Dry cough, sore throat and runny nose are also symptoms of influenza, but not common as first symptoms. Even in a healthy young person, influenza lasts for 10 to 14 days, during which the patient feels clearly ill and weak.

The risk of complications following influenza is greater than that following the common cold; in order to reduce the risk of complications (pneumonia, maxillary sinusitis, myocarditis, otitis), the influenza patient must rest for the duration of the disease (and absolutely avoid sports and heavy exercise!).

An influenza patient should consult a nurse or doctor if:

  • the symptoms last longer than the normal 10 to 14 days 
  • high fever persists for over 3 to 5 days and overall condition deteriorates 
  • fever recurs (after a period of normal temperature) 
  • overall condition and well-being deteriorate so much that coping at home becomes difficult.

Influenza vaccination 

It is possible to use a vaccine chosen according to the year's epidemic to prevent influenza. For healthy persons under the age of 65, the inconvenience caused by influenza is minor compared to risk groups and the elderly, and yearly vaccinations are not necessary. If you want to protect yourself against an influenza infection, you can get vaccinated for a fee in the autumn. The vaccine offers no protection against other respiratory tract infections and thus does not prevent the common cold. (For more information: Article on influenza vaccination)

For further information:
National Public Health Institute KTL - Frequently asked questions
FSHS health articles: Cough and Influenza

The article is made by:
MD Johanna Castrén

Key words: Common cold, Respiratory tract infection