Cold and Flu - Symptoms and Differences

The flu and a cold are different diseases caused by different viruses. You should understand that.

Want to irritate a patient? Go to the doctor with numerous complaints such as fever, a sore throat, body ache and eyes, sneezing and nasal cold, and you will hear a "this is just a simple virus".

Want to annoy the doctor? Tell him/her that the diagnosis of "a simple virus" is only done when the doctor has no idea of the correct diagnosis. But who is right? In fact, both are right and both are wrong.



1.5 billion people worldwide have at least one bout of the flu each year. Also add the fact that hardly anyone can spend a whole year without having at least one episode of a common cold. On average children have 5-7 episodes and adults 3-5 episodes of a cold per year.

Colds and the flu are responsible for more than half of all school and work absences for health reasons. So when the doctor makes the diagnosis of viral infection, the chance of it being right is immense. The problem is not diagnosed, but the term "virus" is very broad and encompasses many different diseases.

Any disease caused by a virus is a viral disease. Just name a few of those already discussed in this website:

• Chickenpox
• Herpes
• Hepatitis A, B and C
• Mononucleosis
• Rubella
• Human rabies
• AIDS
• Mumps
• Dengue
• Labyrinthitis

In fact, there are hundreds of diseases caused by over 3000 different viruses. Doctors can be more precise, saying that it is a viral infection of the upper respiratory system. Still, they face a wide range of differential diagnoses. This is what will be expanded on.

The clinical picture of respiratory viruses is very similar. Because these infections are usually self-limiting and do not require specific treatment, it makes sense to carry out expensive tests and cause inconvenience to the patient only to find out exactly what the virus is responsible for. The most important thing is not diagnostic, but rather identification of the signs of severe respiratory problems (it will be explained below).

Based only on clinical features, we can get an idea of which infectious agent we are dealing with. For example:

• Coronavirus - also cause cold symptoms, and can cause diarrhea, especially in immunocompromised patients. The SARS, which receives much media attention in the early serotype is caused by a coronavirus.
• Respiratory syncytial virus - causes a more symptomatic condition even with sinusitis, otitis, conjunctivitis, cough. In the elderly, the immunocompromised and children can cause pneumonia and lead to death.
• Parainfluenza is the cause of tracheobronchitis and pneumonia, usually more severe in children and the immunocompromised. In adults it causes similar symptoms as a cold frame.
• Influenza is the causative agent of influenza. Very symptomatic. It can cause viral pneumonia or facilitate the emergence of bacterial pneumonia. Eventually, mutations in viruses lead to major epidemics such as the Spanish flu in the early twentieth century. The avian and swine (flu) are caused by a subtype of Influenza.
• Rhinovirus - is the leading cause of common colds. It is a mild disease that rarely causes fever in adults and usually lasts 5-7 days. It can cause exacerbation of asthma. There are over 100 serotypes of rhinoviruses.
• Adenovirus - a framework usually causes a little richer, with fever, pharyngitis, hoarseness, and conjunctivitis. It can cause pneumonia, diarrhea and viral meningitis.

Not really important to know which virus is causing the cold. The point is to differentiate it from the flu. Well, the flu and a cold have been discussed here, but so far not explained what their difference.


A cold is a mild infection of the airways. It can be caused by several different viruses, rhinoviruses being the most common. It is extremely contagious and is transmitted via aerosols from coughing or sneezing and by contact with infected hands.

Symptoms appear 24 to 72 hours after transmission of the virus. It usually lasts 5-7 days, but in 25% of cases the symptoms persist for up to two weeks. Most people have 3-5 cold frames per year.

The most common symptoms are rhinitis, coughing and sneezing. There may be neck pain of short duration in the early days. The cough can last up to weeks after the end of symptoms. Fever rarely occurs in adults. A cold is contagious for only the first 3 days of symptoms.


The flu is caused by influenza virus. It presents a richer clinical picture than a cold, high fever, body aches, headache, malaise, loss of appetite, a sore throat and cough. Symptoms here usually appear suddenly unlike a cold, where they emerge gradually. Cough and fever are early symptoms.

The mode of transmission is equal to the cold. The duration of the disease is usually up to 2 weeks. The time that the patient remains infectious lasts 24 hours or 7 days after termination of foot.

The flu also has a higher rate of complications such as pneumonia or influenza by the opportunistic bacteria. Both the flu and the swine flu have similar clinical and complication rates, being impossible to distinguish without laboratory tests.

In addition to flu vaccine, there are specific remedies against influenza, when indicated, should be administered with a maximum of 48 hours of illness onset. The best known is Tamiflu. Specific treatment is indicated for children, seniors and people with impaired immune systems (immunocompromised). It does not cure the flu, but greatly reduces its duration and helps to prevent complications.

Although it has the image of a mild disease, influenza is responsible for thousands of deaths each year and in all countries. People in risk group described above are more likely to have complications. It is a disease with low mortality rate, but because it is highly contagious (infects more than 1 billion people each year) ends up causing a considerable number of deaths.

It is important to remember that the vast majority of people have several episodes of influenza during the life without ever developing complications. Treatment with antivirals should only be done after medical evaluation. 99% of colds have no indication being treated with Tamiflu.

With the behavior of the tabloid press in the world during the last flu epidemic, millions of people have taken Tamiflu unnecessarily, which resulted in a high rate of resistance of the virus.

The severity signs of influenza are:

• Chest pain while breathing
• Persistent vomiting
• Disorientation
• Low Pressure
• Difficulty breathing
• Changes in consciousness

To prevent influenza a person should:

• Avoid being in low air circulation and with many people
• Avoid bare-hand contact with eyes and mouth without washing
• Avoid close contact with infected people (at least 2 meters)
• Often wash hands

- Is it true that influenza viruses are constantly changing and therefore it is impossible to create a permanent immune defense?
- Yes, Even the flu vaccine is changed frequently, taking into account these new mutant viruses.

- Can I get influenza from the vaccination?
- No, the viruses used are dead and unable to cause disease.

- Some people say they never had the flu and after vaccination began to have it, is that possible?
- No. This makes no sense. What happens is that 10% of Influenza subtypes are not covered, and therefore some vaccinated patients may get flu. Many people get confused with colds and flu.

- Does the flu vaccine cover the cold virus?
- No.

- Can getting a cold or flu being exposed to cold weather?
- In general, colder months are those where there is more virus circulation, and people spend more time in contact with each other indoors. There is no direct relationship between catching a cold or the flu. Nobody gets the flu because of rain or opening the refrigerator with wet body. To get the disease it is necessary to contact with the virus.

- Does Vitamin C prevent viruses?
- There is no evidence.

- Chicken soup is good for curing the flu, isn't it?
- Not good, not bad. As one of the treatments is to increase fluid intake, the chicken soup serves this purpose. Hot foods relieve symptoms of a sore throat. But the chicken itself has nothing in it.

- Swine flu is more severe than seasonal flu, isn't it?
- No. The rates of mortality and complications are similar.