The Common Cold

 Case Scenario:

                          A 2-year-old girl presents with a 3-day history of 38.7-degree centigrade fever, nasal congestion with cloudy rhinorrhea, and conjunctivitis. The pharynx is erythematous and the rest of the exam is normal. She has remained healthy and the rest of the vaccination is completed. The mother is worried and wants to know which antibiotic you will prescribe, as her brother is allergic to penicillin.

                   

Definition:

                            It is a viral infection that is acute, self-limiting, and usually targets the upper respiratory tract(nose and throat). It is usually harmless and many types of viruses can cause a common cold.

Epidemiology:

                                On average, an adult has 4-6 and a child has 6-8 colds per year. The common cold virus can be caused by a variety of different viruses such as Rhinoviruses, respiratory syncytial virus(RSV), Influenza viruses, parainfluenza viruses, and adenoviruses are commonly responsible for colds in pre-school children. Other viruses that cause the common cold include enteroviruses(echoviruses and Coxsackieviruses), coronaviruses, and the newly described human metapneumovirus. Common cold causes around 500 FP visits to the physician per 1000 patients a year. Since colds happen all year round, the burden is more than the burden caused by seasonal viruses. These viral infections happen in only certain months(meaning that each virus has a specific month in which it attacks) throughout the year. and help in narrowing possible etiology as below.

Virus	Month
Rhinovirus(1st peak)	March and April
Parainfluenza	October and November
RSV, Influenza virus, coronavirus	Winter months
Rhinovirus(2nd week)	September
Adenovirus	Continuously in cold months

 

Causes:

             The common cold is most often caused by rhinoviruses. More common cold causes are Respiratory Syncytial Virus(RSV), Influenza viruses, parainfluenza viruses, and adenoviruses. The uncommon causes of The common cold are the Enteroviruses(echoviruses, and Coxsackie viruses), coronaviruses, and human metapneumoviruses.

Symptoms:

                   The characteristic symptoms are clear to green nasal discharge and mild to moderate fever is common in children during the first 3 days of the illness. Other symptoms may include:

• Sore throat
• Cough
• Congestion
• Slight body aches
• Sneezing
• Generally feeling unwell

Physical signs are non-specific but may include erythema and swelling of the nasal mucosa, none to mild pharyngeal erythema, and anterior cervical lymphadenopathy.

Complications:

• Otitis media 
• Asthma attack
• Sinusitis
• Strep throat
• Pneumonia
• Bronchitis. 

Transmission: 

                                  It occurs by the inhalation of small particles aerosols, or large particles getting stuck in your nasal pathway or hand-to-hand contact. You can also get infected by stool or respiratory secretions from another person.

Danger Signs:

                       In children

•  Cyanosis
• Ribs pulling in with each breath 
• Breathing difficulty
• Severe muscle pain(Child refuses to walk)
• Coma/Lethargy
• Dehydration(no urine for 8 hours, dry mouth, no tears while crying)

                               In adults:

• Difficulty breathing
• Persistent pain or pressure in the chest or abdomen
• Persistent dizziness, confusion, inability to arouse.
• Seizures
• Not urinating
• Severe muscle pain
• Fever or cough that improves but returns or worsens
• Worsening of chronic medical conditions

A cold and influenza should be differentiated because the cold is harmless and usually clears up by itself meanwhile influenza can cause pneumonia and even death.

Table 1. Differences between common cold and influenza

Common Cold	Influenza
Low or no fever	High fever
Symptom onset is gradual	Symptom onset is abrupt
Stuffy, runny nose	Clear nose
Chills are uncommon	Chills are common
Mild, hacking cough	Cough, often becoming severe
Sneezing Is common	Sneezing is unusual
Mild fatigue	Several weeks of fatigue
Headaches are rare	Headaches are very common
Normal energy level	Extreme exhaustion

 Diagnosis:

• Diagnosis is made on clinical grounds upon the characteristic history, symptoms, and signs on physical examination
• If the doctor suspects that you have a bacterial infection or something he may order an X-ray Scan. 
• Rapid viral testing can be done for rapid diagnosis

Management:

                       Most cases of Common cold get better without treatment, usually within a week or 10 days. But the cough may linger for a few more days. The best thing you can do is take care of your body while it heals. for example: Get adequate rest, use saline nasal rinses and drink plenty of liquids.

Antibiotic Therapy:

                                                   Never take antibiotics to cure a Common Cold. It will make the body resistant to the antibiotic and if a real bacteria attacks then the body won't respond to antibiotics. the biggest example of this mechanism is the XDR typhoid.

Prevention:

• Wash your hands before and after preparing and eating food, Wash your hands after coming from the bathroom.
•  Avoid touching your face
• Clean frequently used surfaces
• Use hand sanitizers
• Strengthen your immune system by eating healthy diets and sleeping well.
• Stay home while you are sick to avoid the spread of the virus

                                                   

References and citations:

1. www.mayoclinic.org; The common cold, symptoms, and causes; Heading of causes and 1st paragraph
2. https://www.ncbi.nlm.nih.gov; The article was cited by PMC; Heading, Epidemiology and symptoms; 1st paragraph; First 4 lines
3. https://www.healthline.com; Written by the health line editorial team; Complications of the common cold.
4. Website of CDC; Written by CDC; How to stop the transmission of the common cold and cold vs influenza
5. www.mayoclinic.com; The common cold diagnosis and treatment;