Unlike the common cold, the onset of symptoms for flu (or Influenza) is very sudden and fast. While cold and flu are both infectious viral illnesses, cold symptoms are usually only confined to the nose and head. But the flu is a much more severe disease, with symptoms such as fever, chills and body aches. A person suffering from the common cold can generally walk about and work but a flu patient usually does not feel like getting out of bed. Over 30,000 individuals die from the flu every year in the United States.
|Symptoms||Cough, aches, fatigue, sore throat, runny or stuffy nose, sneezing, stuffy nose, sometimes skin reaction.||Flu symptoms appear quickly (within 3-6 hrs) and include fever, chills, severe aches and chest discomfort.|
|Treatment||Antihistamines, Decongestants, nonsteroidal anti-inflammatories, extra rest, drink plenty of fluids.||Sometimes antiviral medication helps control the flu but often patients simply wait for their body to fight the virus and overcome the disease. Medication is also available to ease patient comfort.|
|Fatigue||Sometimes||Moderate to severe|
|Aches||Sometimes||Usual and often severe, affects the entire body.|
|Severity||Very little risk of complications or serious health problems unless health and immune system are otherwise seriously compromised already.||Serious health problems, such as pneumonia, bacterial infections can occur.|
|Chest discomfort||Rare||Often severe|
Symptoms of Common Cold vs. Flu
The flu (influenza) is a lot more serious than a common cold. With a cold, the symptoms are centered around the nose and throat. But the flu tends to make the whole body ache the patient is sick all over.
The symptoms of a cold include a runny or blocked nose, sneezing, minor throat irritation, mild fever, sore throat, a feeling that your ears are blocked, and finally colored mucus or nasal discharge (which means that your immune system is fighting the infection).
Symptoms of influenza usually start suddenly with a high fever and you may feel sick enough to go to bed. Other symptoms include, irritation in the throat or lungs, a dry cough, high fever, shivering, sweating and severe muscle aches.
Tests are available to diagnose the flu but there are no such tests for colds.
Infection mechanism for common cold vs flu
Both illnesses are airborne and contagious, the flu more so because of its short incubation period. The most common way to catch the flu or a cold is to inhale droplets from coughs or sneezes. Sneezes expel a significantly larger concentration of virus "cloud" than coughing. The "cloud" is partly invisible and falls at a rate slow enough to last for hours—with part of the droplet nuclei evaporating and leaving much smaller and invisible "droplet nuclei" in the air. Droplets from turbulent sneezing or coughing or hand contact also can last for hours on surfaces. The incubation period (time between becoming infected and developing symptoms) is 1-3 days. The infectious period (time during which an infected person can infect others) begins about 1 day before symptoms begin, and continues for the first 5 days of the illness. Symptoms, however, are not necessary for viral shedding or transmission, as a percentage of asymptomatic subjects exhibit viruses in nasal swabs, likely controlling the virus at concentrations too low for them to have symptoms.
Treatment for Common cold
There is no cure for the common cold. Treatment is limited to symptomatic supportive options, maximizing the comfort of the patient, and limiting complications and harmful sequelae. The most reliable treatment is a combination of fluids and plenty of rest. The National Institute of Allergy and Infectious Diseases suggests getting plenty of rest, drinking fluids to maintain hydration, gargling with warm salt water, using cough drops, throat sprays, or over-the-counter pain or cold medicines. Saline nasal drops may help alleviate congestion.
The common cold is self-limiting, and the host's immune system effectively deals with the infection. Within a few days, the body's humoral immune response begins producing specific antibodies that can prevent the virus from infecting cells. Additionally, as part of the cell-mediated immune response, leukocytes destroy the virus through phagocytosis and destroy infected cells to prevent further viral replication. In healthy, immunocompetent individuals, the common cold resolves in seven days on average.
Although some people take antibiotics to treat common cold, doctors believe that antibiotics are not at all effective in treating common cold. This is because cold is caused by a virus and not a bacteria.
People with the flu are advised to get plenty of rest, drink a lot of liquids, avoid using alcohol and tobacco and, if necessary, take medications such as acetaminophen (aka paracetamol) to relieve the fever and muscle aches associated with the flu. Children and teenagers with flu symptoms (particularly fever) should avoid taking aspirin during an influenza infection (especially influenza type B) because doing so can lead to Reye's syndrome, a rare but potentially fatal disease of the liver. Since influenza is caused by a virus, antibiotics have no effect on the infection; unless prescribed for secondary infections such as bacterial pneumonia, they may lead to resistant bacteria. Antiviral medication is sometimes effective, but viruses can develop resistance to the standard antiviral drugs.
The two classes of anti-virals are neuraminidase inhibitors and M2 inhibitors (adamantane derivatives). Neuraminidase inhibitors are currently preferred for flu virus infections. The CDC recommended against using M2 inhibitors during the 2005–06 influenza season.
TAMIFLU, a brand for the drug oseltamivir, usually helps only if taken within 24 to 48 hours of the onset of the first symptoms. While it does not "cure" the flu, it can help relieve some symptoms and speed up recovery. Note, however, that pediatricians generally do not prescribe TAMIFLU to very young children because of the potential side effects such as hallucinations. Researchers have raised serious concerns about Tamiflu, not just its effect on mental health but even the efficacy of the drug:
Cochrane [researchers] concluded the [clinical] trials don’t prove that Tamiflu prevents hospitalizations, contagiousness or complications. The only thing it definitely does do, Cochrane said, is shorten the duration of symptoms, by about a day.
Another difference between common cold and the flu is that the flu is preventable. Every year, only a handful of strains of the influenza virus cause most of the flu across the world. Consequently, scientists work on the flu vaccine every year. While the vaccine is fairly effective, unanticipated flu strains can evolve against which the vaccine will fail. A nasal spray flu vaccine is also available.
Myths about the flu shot
Here are some common misconceptions about the flu shot:
- The flu shot causes the flu. The truth is that a flu shot takes up to two weeks to become effective; so if a person gets infected before the vaccine has had enough time to work, she will fall sick.
- It's too late to get vaccinated if you have already had the flu this year. The flu vaccine is designed to protect against multiple strains of the influenza virus. It is possible to get the flu more than once, each time caused by a different strain. Even if you have had the flu, a vaccine can still protect against other strains of the virus.
- Flu shots are 100% effective. The truth is you can still fall sick with the flu even after being vaccinated. However, CDC estimates have found that vaccinated people are 62% less likely to get the flu and at far lower risk of requiring medical care if they did get sick.
- People who are allergic to eggs can't get a flu shot. Flu shots are risky only if you have severe egg allergies. Most people who have egg allergies are not at risk of any complications with a flu shot. Side effects are mild, such as hives or itchy skin.
Humidity and the flu virus
Scientists studying the link between the flu virus and humidity in the air have concluded that the virus thrives best when humidity is either over 98% or between zero and 50%. Dr. Linsey Marr, a researcher at Virginia Tech, recommends using a humidifier to keep humidity levels around 50% (but not over 60%, because that can cause mold buildup) to give the flu virus the least chance of survival.
Preventing the common cold
On the other hand, the common cold is caused by a large variety of viruses, which mutate quite frequently during reproduction, resulting in constantly changing virus strains. Thus, successful immunization is highly improbable.
The best way to avoid a cold is to avoid close contact with existing sufferers; to wash hands thoroughly and regularly; and to avoid touching the mouth and face. Anti-bacterial soaps have no effect on the cold virus — it is the mechanical action of hand washing that removes the virus particles.