Life Cycle And Stages of the Common Cold

The common cold, also known as an upper respiratory infection (URI), is a self-limited viral illness that is aptly named as it affects millions in the United States annually. It is estimated adults in the U.S. get about 2-3 colds per year and children can have up to 6-8 a year.

In fact, there’s a good chance that many of you reading this may be experiencing a common cold right now. You’ve likely heard that colds clear on their own, but when exactly will you start to feel better?

And when can you return to work or school without putting others at risk? In this article, I’ll discuss the common cold in more detail, including its symptoms and causes, the stages of the common cold, and how to treat it. 

What is the Common Cold?

The common cold is a viral infection of the upper respiratory tract. It can affect your nose, throat, and sinuses.

Symptoms

The common cold has a range of symptoms and the severity to which these are felt can vary from person to person.

They include:

• Sore throat
• Cough
• Sneezing
• Runny or stuffy nose
• Headache
• Low-grade fever
• Mild body aches
• Fatigue

These symptoms are similar to those of other respiratory illnesses like the flu, although cold symptoms are typically milder.

Causes

There are over 200 viruses that cause the common cold. Rhinoviruses account for 10-50% of all colds, while coronaviruses account for 10-15%.

The coronaviruses that cause the common cold are different strains from the SARS-CoV-2 virus responsible for COVID-19. Other viruses that cause the common cold include adenovirus, respiratory syncytial virus, parainfluenza virus, and enterovirus. 

The virus spreads from an infected person through direct contact or droplets released into the air. It can also spread by touching infected surfaces like doorknobs and toys and then touching your mouth, nose, or eyes with unwashed hands. 

Colds are more common in children for several reasons: their immune systems are still developing, they usually play closely with other kids who may have the virus, and they have poor hygiene practices. Cold weather does not cause a cold, although people often catch a cold during winter and spring.

This is because more people are indoors during these periods, making it easier to spread from infected persons to others.

Stages of the Common Cold

Colds are self-limiting, which means they usually resolve without treatment. This typically takes about 7-10 days and the lifecycle can be divided into stages.

Stage 1 – Infection/Incubation

This stage is the period between the infection by the virus and the appearance of symptoms. It can last between 1-3 days, although you can develop symptoms as early as 12 hours after exposure. At this stage, you are already contagious even though you’re not experiencing symptoms yet.

Stage 2 – Symptoms Appear/Peak

Symptoms usually appear and peak the following 3 days and include sore throat, cough, sneezing, and a general feeling of unwellness. Fever is generally more common with children than adults.

Stage 3 – Symptoms Begin to Fade

Symptoms begin resolving and by day 7-10, the majority of people will feel relief.

Stage 4 – Recovery

An individual might still feel some residual symptoms, like fatigue or cough, beyond 10 days. There is even a condition, known as post-infectious or post-viral cough, that can last for up to 6-8 weeks. 

How to Treat the Common Cold

As a cold is a viral infection, it is not treated with antibiotics, but there are some medications and remedies that can help you feel better. Below are some common treatments to manage symptoms. 

OTC Medication

Over-the-counter (OTC) medications can be purchased without a prescription.

OTC medications that can help with cold symptoms include:

• Pain relievers: Medicines like ibuprofen (Advil) and acetaminophen (Tylenol) help to reduce symptoms like headache and also lower fever. However, it is important that you stick with the prescribed dose in the patient information leaflet and do not use them for prolonged periods of time. Additionally, do not give acetylsalicylic acid (Aspirin) to children and teenagers because it puts them at risk of a dangerous condition known as Reye’s syndrome. 

• Antihistamines: Antihistamines are drugs used to relieve symptoms of allergies such as sneezing, congestion, watery eyes, and runny nose. They help decrease secretions and mucus and post nasal drip. OTC antihistamines include cetirizine (Zyrtec), loratadine (Claritin), levocetirizine (Xyzal) and diphenhydramine (Benadryl).

• Decongestants: Topical or oral decongestants like pseudoephedrine (Sudafed) reduce swelling, inflammation, and mucus production in the nasal passages, which can relieve stuffy nose. 

• Cough suppressants: Cough suppressants, also known as antitussives, work by controlling your cough reflex to help you stop coughing. An example of a suppressant is dextromethorphan. But be careful not to overuse cough suppressants, as coughing is the body’s mechanism for expelling mucus.

• Expectorants: OTC expectorants like guaifenesin (Mucinex) help to thin mucus in your airway so that it’s easier to cough out. 

Cold and cough medicines are usually available in combination. Consult a doctor before giving cold medicines to children under six years of age because some have potentially dangerous side effects. 

Make sure to check the ingredients of your medications and understand their dosage, so you don’t take too much of a particular ingredient. If you’re taking other medications, check with your doctor or healthcare provider before using these medicines to avoid possible drug interactions.

Home remedies

Home remedies are safe and may help to reduce your discomfort.

• Hydration: Stay well hydrated by drinking plenty of fluids (water, popsicles, broth).

• Humidifier: Dry air can further irritate your nasal passages. A humidifier ensures a comfortable level of moisture in the air. 

• Sleep and rest: Sleep affects the functioning of your immune system, so make sure to get a good night’s sleep and rest as much as you can throughout the day. 

• Gargling warm salt water: Warm salt water may help soothe a sore throat. Add ½ teaspoon of salt to an 8-ounce glass of warm water. Ensure the water is not too hot so you do not scald your tongue and throat, causing more discomfort. Do not give this treatment to children because they are unable to gargle properly.

• Hot pack for sinus: To make a hot pack, place a damp washcloth in a microwave and heat on high for two minutes. You can also put a washcloth in warm water and wring out the excess water. Then, place it over your face, across your nose below your eyes, to relieve the discomfort caused by congested sinuses. 

• Vitamins and supplements: Vitamin C, D, and zinc aid your immune system.

• Honey: You can add honey to your tea or put it in warm lemon water to soothe a sore throat. But don’t give honey to children under one year old because of possible contamination with Clostridium botulinum, which causes infant botulism.

You can try one or more of these home remedies to help you feel more comfortable while the infection clears.

When to See a Doctor

Generally, you do not need to visit a doctor for a common cold because it clears on its own. But a common cold can lead to complications, in which case, you need to see a doctor.

Some symptoms to look out for include:

• Difficulty breathing
• Wheezing
• Chest pain
• Common cold symptoms lasting more than 10 days
• Blood streaked mucus
• High-grade fever (greater than 101.3F (38.5°C)
• Fever lasting more than two days
• Lightheadedness
• Fainting
• Vomiting

If your child presents with severe common cold symptoms, or if a child under three years old has a cold, take them to their pediatrician.

How K Health Can Help

If your symptoms persist for more than 10 days and are severe, you need medical attention.

Did you know you can access online urgent care with K Health?

Check your symptoms, explore conditions and treatments, and if needed, text with a healthcare provider in minutes. 

K Health’s AI-powered app is based on 20 years of clinical data.