The common cold is an infectious respiratory disease that affects the nose, sinuses, throat and larynx. It is caused by one of several hundred virus strains. It is different from influenza, or the flu, in that it is caused by different types of viruses and is a more mild viral infectious disease, with more moderate symptoms and typically shorter in duration. The common cold has no known cure, but responds well to bed rest, generous fluid intake and symptoms management. Complications may occur as a result of secondary bacterial infections or immune system deficiencies. Prevention includes good hygiene, avoiding large groups of people and crowded places in the cold season and any measure that contributes to a stronger immune system.
Common cold causes. What causes the common cold are viruses. Common cold virus types include: rhinoviruses (around 100 known strains), coronaviruses, adenoviruses, human respiratory syncytial virus, the human metapneumovirus, enteroviruses and others. There are an estimated of 200 different virus strains that cause the common cold, the most common being rhinoviruses.
Rhinoviruses are a class of viruses that primarily infect the nose and throat, which is why the common cold is an infection restricted to the upper respiratory tract. They thrive at temperatures of around 33 degrees Celsius which coincide with the temperature in the nose and throat as a result of inhaling air. The temperature in the lower respiratory tract is typically higher, hence the reason why the common cold does not affect the lungs, for example. Rhinoviruses and other viruses causing the common cold use the nose, mouth and eyes as entry points.
How long does it take to catch a cold? It takes a few seconds or less to catch a cold. As soon as you come into contact with one or more of the couple hundred common cold viruses, the infection has begun. Usually, the entry points for the virus are the nose, mouth or eyes. If the virus enters through the nose, it takes 10 to 30 minutes for it to be sent to the back of the throat to the adenoid tonsils where it will attach and start replicating.
How long does it take for a common cold virus to incubate? Depending on the virus strain, the common cold incubation period may take anywhere from 8 to 16 hours or slightly more. Usually, it takes less than a day for a common cold virus to replicate and as little as one virus particle or up to several dozens are enough to produce infection.
Symptoms may appear within 24 hours of infection, but no sooner than 16 hours and typically reach a peak in 2-4 days, after which they should start decreasing in intensity, provided you enjoy bed rest, drink sufficient fluids and eat well. If symptoms get progressively worse and the cold doesn’t seem to go away in 7 to 10 days, it is important to see a doctor. At this point, complications such as a secondary infection, particularly a bacterial infection are suspected to have occurred.
How long does a cold last? On average, a cold lasts 7-10 days. So it takes roughly 1 week to 1.5 weeks for a cold to go away in otherwise healthy adults. But if you don’t take good care of yourself or have other medical issues such as chronic illnesses of the respiratory system, some symptoms of a cold may last up to 3 weeks. Typically, only mild symptoms such as a slight runny nose or occasional stuffiness, infrequent sneezing, minor aches, coughing may persist after 10 days.
Cold types. Depending on the duration of the infection and the time needed for symptoms to be cleared and the person to return to their normal activities, colds may be classified as:
1) Minor colds. They can last as little as 2-4 days and present with very mild symptoms that do not impact the capacity to perform daily activities. Such a short duration may be a result of a very small virus load, strong immune system response, previous infection resulting in acquired immunity and overall strong health.
2) Average cold duration is 7-10 days. Symptoms peak around days 2-4, after which they progressively become milder until they disappear.
3) Severe colds may last from 2 to 3 weeks and are characterized by stronger symptoms. They are more likely to occur if you have existing respiratory conditions (example: asthma, chronic obstructive lung disease), immune system deficiencies, nutritional deficiencies, suffer from dehydration, lack of sleep and can predispose to complications such as secondary infections. Newborns, children, the elderly and immunodeficient individuals are most at risk for complications.
What are the symptoms of a common cold? You can tell you have a cold based on the following signs and symptoms:
1) Tickle sensation in the throat, dry throat.
2) Occasional sneezing.
3) Sore throat, hoarseness.
4) Runny nose with watery mucus at first.
5) Experiencing chills or cold sensitivity.
6) Stuffy nose, possible sinus pain.
7) Coughing, thick mucus and mild chest discomfort.
8) Minor to moderate aches and pains.
9) Feeling tired, malaise, low vitality.
10) Fever is uncommon.
If it does occur, it is usually low-grade fever.
11) Lack of appetite may occur as a result of malaise.
12) Heavy eyes, earaches, especially in children.
Risk factors. Here are some behaviors that can increase your risk of catching a cold:
1) Direct contact with infected persons and their personal objects.
Example: eating or drinking after someone who is sick, being sneezed on, being coughed on, shaking hands (if the person is sick and hasn’t washed their hands) etc.
2) Indirect contact with infected surfaces.
Examples: door handles, desks, counter tops, any indoor surface really.
3) Crowded places, especially in fall or winter and predominantly indoors.
Examples: day care, school, work, pharmacy, public institutions, public transportation, but also concerts, meetings etc.
4) Poor hygiene. Not washing hands often, for example before and after eating, going to the toilet, shaking hands with people, touching door handles etc. Not using disposable tissues or covering your cough with your hands etc.
5) Having a family member, someone you live or closely work with down with a cold.
6) Exposure to cold. Examples: if it’s cold where you live, work or study, spend time outdoors in low temperatures.
7) Lack of sleep. It lowers immune system defenses.
8) Stress and fatigue make you susceptible to poor immunity.
9) Nutritional deficiencies, malnutrition, anorexia. Because the immune system relies on vitamins like vitamins A and C, minerals like zinc and macronutrients like protein to work optimally.
10) Chronic illnesses of the respiratory tract. Examples: asthma, chronic obstructive pulmonary disease.
11) Innate or acquired immunodeficiency, disorders of the immune system and conditions caused by them, smoking.
Common cold treatment. Because it is a viral infection and viruses mutate continually, there is currently no cure for the common cold. Fortunately, a functional immune system is perfectly capable of fighting off the infection naturally. The immune system will only require support in the form of symptoms management, sufficient fluid intake and good nutrition.
There is currently no vaccine available for the common cold. This is mostly due to the fact there are too many viruses and strains causing it. However, a patent for a common cold vaccine caused by rhinoviruses has been recently registered.
Common cold and antibiotics. Antibiotics are for bacteria, but the common cold is caused by viruses, so they are inefficient and will do nothing to treat the cold if prescribed. However, antibiotics should only be prescribed in cases of bacterial infections secondary to the common cold, usually occurring in children, the elderly and anyone suffering from immunodeficiency. Below is an interesting video that explains what viruses are and how they infect cells in order to produce viral infectious diseases like the common cold:
Generally, a healthy person fully recovers from the common cold, provided they enjoy bed rest, drink sufficient fluids and eat to support the immune system fighting the infection. Older people with weaker immune systems, children with underdeveloped immune systems and anyone immunodeficient are at risk of serious complications. Here is what to do to get over the common cold faster:
1) Stay hydrated. Drink plenty of water, warm teas if you are not allergic, sports drinks, eat soup.
2) Eat well. Whatever symptoms you may be experiencing, eat to help your immune system.
3) Chicken soup. It provides liquids for keeping hydrated, meat rich in protein to help the immune system and B vitamins for vitality. Studies show it reduces inflammation and improves symptoms such as nasal congestion.
4) Bone broth. Can help with symptoms management. Both chicken soup and bone broth should be organic.
5) Rest. Take 2-3 days to rest. Make sure you sleep and keep activity at a minimum to allow for recovery.
6) Stay indoors and keep warm. Exposure to cold can worsen symptoms and lengthen recovery.
7) Use a humidifer or vaporizer to maintain a good level of humidity, relieve nasal congestion and ease cough.
8) Saline solution-based nasal decongestants can help with congestion.
9) Use nasal decongestant sprays. Personally, I avoid them because they cause rebound congestion, even within the recommend time frame of use. I use nasal decongestants with only saline solution and have come to the conclusion they work even better and have no side effects. See articles on side effects of nasal decongestants and rebound nasal congestion.
10) Pain relieving medication can help with aching, but it’s best to avoid it and just rest. The symptoms will go away in a few days anyway.
11) Exercise. After symptoms peak, it could be good for you to take a short walk. Light physical exercises could also help with the aches and pain and improve mood. Make sure you don’t go out in the cold and avoid crowded places to prevent the spread of the cold to others.
12) Cough syrups could help relieve cough, but are best avoided if the cough is mild. Children under the age of four should not be given cough medicine or syrups. Talk to a pediatrician for further advice.
13) Herbal teas. Drinking warm herbal teas could help with nasal congestion, relieve cough and sore throat. Just make sure you check for allergies. Pregnant women should avoid herbal teas.
14) Raw honey. Soothes a sore throat, forms a protective coating that relieves irritation and discomfort, reduces bacterial load thanks to its antimicrobial properties. Any raw honey is good (see all honey varieties), but make sure you are not allergic to honey or bee products and always get certified honey to prevent contamination with bacteria, heavy metals or toxins.
15) Lemon juice in tea helps break down thick mucus.
16) Ginger in tea may help relieve nasal congestion.
17) Echinacea may help improve symptoms, but make sure you are not allergic to it.
18) Throat candy with lemon, honey, zinc or antiseptics can help with recovery.
19) Saltwater gargle can help soothe a sore throat.
20) Vitamin C and zinc dietary supplements can help with recovery. However, they are even better for reducing the risk of catching a cold or other respiratory infection, easing symptoms and reducing the duration of the common cold.