Common cold refers to any specific viral or group of viral diseases that affect the parts of the upper respiratory tract like the sinuses (sinusitis) and the pharynx (pharyngitis). It sometimes affects the eyes causing conjunctivitis [1].
Presentation
The typical symptoms are cough, which is milder most of the times. They may also have a runny nose, nasal congestion sore throat, and the color of the nasal secretion may vary form clear to green thick secretion. There might also be fatigue, feeling of mild depression, headache, loss of appetite and muscle ache. Fever is a common presenting symptom in infants but not generally present in adults. If fever is seen in an adult, influenza should be considered [7].
Some patients may present with complications like otitis media, chronic bronchitis, otitis media. Aggravation of reactive airways in susceptible patients.
Workup
Diagnosis of common cold can generally made on the basis of a thorough history and the typical physical findings. If the history and physical examination point to a viral cause, a serious work up is unnecessary.
The white blood cell count might be elevated within the first 3 days although this has little clinical relevance or diagnostic value. Complete blood count and Erythrocyte sedimentation rate also have no benefit. Viral cultures have little or no significant clinical value because of the prolonged time it takes to obtain the result.
Isolation of the particular strain of virus is difficult and even if it is possible, has no bearing on the clinical course or outcome.
If the specific viral diagnosis is however required, culture can be obtained from nasal secretions. Real-time microarray and Polymerase chain reaction could also be used.
If there is suspicion of a secondary infection, then a bacteria culture should be done. A chest x-ray should also be done if involvement of the lower respiratory tract is suspected.
Treatment
There is no known cure for common cold, as such, treatment centers on providing symptomatic relief and supportive care [8].
Supportive care include; nursing at a 45 degree angle, plenty of rest, proper hydration, disinfecting the environment, use of decongestants, cessation of smoking and alcohol, eating hot soups, and use of nasal saline drops.
Medication that may be used include analgesics for pain, decongestants to relieve the airways and antihistamines to mediate the inflammatory reaction [9].
Antibiotics may be used if a bacterial superinfection is suspected.
Prognosis
The common cold is a self-limiting disease and the attacks are generally mild. The patients begin to show signs of improvement within a week. Half of infected individuals attain full recovery within 10 days while by day 15, over 90% of cases would have been resolved. Complications, though rare, may occur in young children, the elderly, the malnourished and the immunosuppressed. Secondary bacterial infection may complicate up to 30% of cases [6].
Etiology
It is caused by a number of viruses. The most implicated virus is a type of picovirus called rhinovirus. Others viruses are influenza virus, human coronavirus, adenovirus, human respiratory syncytial virus, enterovirus, parainfluenza virus and a host of many other viruses. Usually, one or more virus may be responsible for a particular attack.
It is a communicable disease and is transmitted via aerosols, direct contact with secretions from sick people and from contaminated object [2].
Aggravating factor for this condition includes cold weather. Most of the viruses causing common cold thrive during the cold seasons for yet undetermined reasons. This has led to a belief that it can be caught from prolonged exposure to cold weather. There are number of hypothesis to explain increased susceptibility to cold viruses during the cold seasons. Other risk factors are poor immunity, malnutrition and sleep deprivation.
Epidemiology
The common cold is the most common disease affecting the human race. It affects people of all ages, all races and both sexes. It affects children more than adults, affecting children as many as 12 times a year compared to 5 times in adults. Low income earners and the underdeveloped population are at increased risk of developing complications from common cold [3].
Pathophysiology
The mechanism of the response of the immune system is specific for the causative virus. Rhinoviruses which are characteristically acquired by direct contact, bind to some receptors in humans via unknown mechanisms and trigger the release of inflammatory mediators. These inflammatory mediators are responsible for the symptoms seen in common cold. Rhinoviruses typically do not damage the nasal epithelium [4].
Respiratory syncytial virus is acquired through droplet infection and direct contact. It first replicates in the nose and then the throat, as it continues its spread to the lower respiratory tract. This virus will damage the epithelium [5]. The symptoms seen in common cold are primarily due to the immune response to the viral invasion.
Prevention
Due to the mode of spread, preventive measures include regular handwashing, avoiding putting the finger in the nose and eye, use of hand-sanitizers and the use of facemasks when the person is around infected people [10].
Summary
Common cold is caused by virus and it is infectious and communicable. It is also a fairly common disease and can affect a person more than once a year. Like most viral disease, it has no cure and is self-limiting, running its course within a week.
Patient Information
Definition: Common cold is a disease of the upper respiratory tract like nose and throat. It is a very common disease and it affects people of all ages. It is self-limiting.
Cause: It is caused by one of several viruses including rhinovirus and parainfluenza virus. Some of these viruses thrive in the colder seasons. It can be spread by inhaling aerosols from infected persons, touching infected secretion or contaminated surfaces and then touching the eye or nose.
Symptoms: These include, cough, runny nose, congested nostrils, and sore throat. Patient may also have headache, weakness, muscle pain, loss of appetite and a general feeling of unwell.
Diagnosis: Diagnosis is usually clinical, and made by the doctor. Laboratory tests offer no significant clinical value and are only ordered on very rare occasions.
Treatment: This is usually supportive and it is aimed at relieving the nasal congestions, reducing the pain and managing the inflammation. This can be done by a number of drug and non-drug regimen.
References
- Puhakka T, Mäkelä MJ, Alanen A, et al. Sinusitis in the common cold. J Allergy Clin Immunol 1998; 102:403.
- Gwaltney JM Jr, Moskalski PB, Hendley JO. Hand-to-hand transmission of rhinovirus colds. Ann Intern Med 1978; 88:463.
- Heikkinen T, Järvinen A. The common cold. Lancet 2003; 361:51.
- Turner RB. Epidemiology, pathogenesis, and treatment of the common cold. Ann Allergy Asthma Immunol 1997; 78:531.
- Hall CB, Douglas RG Jr. Modes of transmission of respiratory syncytial virus. J Pediatr. Jul 1981;99(1):100-3.
- Thompson M, Vodicka TA, Blair PS, et al. Duration of symptoms of respiratory tract infections in children: systematic review. BMJ 2013; 347:f7027.
- Tyrrell DA, Cohen S, Schlarb JE. Signs and symptoms in common colds. Epidemiol Infect 1993; 111:143.
- Simasek M, Blandino DA. Treatment of the common cold. Am Fam Physician 2007; 75:515.
- Luks D, Anderson MR. Antihistamines and the common cold. A review and critique of the literature. J Gen Intern Med 1996; 11:240.
- Jefferson T, Del Mar C, Dooley L, et al. Physical interventions to interrupt or reduce the spread of respiratory viruses. Cochrane Database Syst Rev 2010; :CD006207.