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Fundamental Facts About Flu or Influenza

Written by
Dr. Agatha
and medically reviewed by Dr. K. Shobana

Published on Sep 28, 2018 and last reviewed on Apr 02, 2022   -  5 min read


‘Flu’ can be a commonly-heard-of term, but its complications are unheard of. Read the article to gain fundamental knowledge about influenza to prevent its occurrence.

Fundamental Facts About Flu or Influenza

What Is Influenza?

Influenza is a common viral infection that can be deadly, especially in high-risk groups. It is a respiratory infection that can spread even before the person knows that they are infected. Many people confuse the flu with the common cold. Both are different in terms of their severity. It can spread very easily but is also preventable through vaccination. It is easily diagnosed and treatable once the symptoms occur. It is a short-term illness that resolves within days or weeks. However, it is highly contagious and spreads through coughs or sneezes.

How Is the Common Cold Different From the Flu?

Influenza is a common viral infection that can be deadly, especially in high-risk groups.

How Prevalent Is Influenza?

Influenza is a contagious disease that sometimes can occur as an epidemic. Globally, about 500,000 people die each year due to the flu. The majority of these deaths occur among people over 65 years. This is mainly in industrialized countries. A flu epidemic occurs when a large number of people in one country are infected, and this can last several weeks.

Experts in health and government agencies globally say that the single best way to protect oneself from catching the flu is to get vaccinated every year. This will save and protect people from experiencing flu epidemics which can cost a country lots of money and loss of lives. In addition, this kind of information will empower people to be aware and take necessary action to protect themselves from severe flu infections.

What Causes Influenza?

Viruses cause influenza. Although these viruses have been present for quite some time, developing vaccinations and herd immunity is difficult due to their mutations. Different strains of these viruses appear at regular intervals.

During talking, sneezing, or coughing by an infected individual, the influenza viruses are released as air droplets, which cause their spread. Another individual can take up the virus by either inhaling the air droplets or picking up the virus from objects touched by the affected individual.

An infected individual can spread the virus even before a day they exhibit symptoms or after five days of developing symptoms. This is much longer in young children or people with compromised immune systems.

What Are the Symptoms of Flu Infection?

Symptoms of flu may range from mild to severe, which can sometimes result in mortality. These include:

Who Is at Risk of Developing Influenza?

People at high risk of contracting flu infection are:

How Is Influenza Diagnosed?

Influenza infection is diagnosed by physical examination and PCR tests.

  1. Physical Examination:

During a physical examination, the doctor looks for the signs and symptoms of the influenza virus to reach a diagnosis. Also, with COVID-19 infections happening around the corner, it is essential to distinguish between the conditions to determine the severity and provide prompt treatment.

  1. PCR Tests:

PCR (polymerase chain reaction) tests can be used to diagnose influenza and COVID-19 infections.

  1. Other Tests:

Usually, lab tests or imaging are rarely required for diagnosing influenza infections. However, in some cases, they might help identify the severity of the disease.

How Is Influenza Treated?

Antibiotics are not necessary as it is a viral infection. Flu is basically treated with rest and fluids to let the body fight the infection independently. Over-the-counter painkillers can be used to relieve pain and reduce symptoms. The annual flu vaccine helps prevent flu and reduce complications. Supportive care is mainly through fluid replacement, and personal care is done through bed rest and throat lozenges.


Decongestants and cough suppressants are given to help relieve symptoms. Decongestants are expected to reduce nasal congestion, swelling, and running nose. At the same time, cough suppressants help block cough reflexes and thin down and loosen the mucus, making easy clearance of the airway.

Nonsteroidal anti-inflammatory drugs are also used to relieve pain, fever and decrease inflammation. In addition, analgesics like Paracetamol are used to alleviate pain, and sometimes antiviral medications are used to reduce the ability of the viruses to replicate.

What Are the Complications of Influenza?

Some of the influenza complications include:

How Can We Prevent Influenza?

  1. Vaccinations:

An ideal way to prevent influenza infection is to get the vaccination at the right turn. Influenza vaccines prevent the risk of acquiring the disease and reduce disease severity, even when it occurs. As a result, these vaccines reduce the rate of hospitalization in individuals affected with flu. The vaccinations are available in the form of intramuscular injections or nasal sprays.

According to the Center for Disease Control and Prevention, vaccination for flu is recommended annually for every individual aged above six months. The need for getting a flu vaccine is much more increased with the evolution of COVID-19. Both the vaccinations for COVID-19 and flu can be taken together. However, it is essential to contact your healthcare provider before you get the vaccine.

  1. Other Preventive Measures:

Influenza vaccines provide a good range of protection against flu. However, these cannot entirely prevent the occurrence of disease, which raises the need for following adequate preventive measures. Below are the methods of controlling the infection spread:

  1. Wash your hands for at least 20 seconds with water and soap. In places where water is unavailable, using alcohol-based sanitizer is recommended.

  2. Abstain yourself from touching the areas of the face like the nose, mouth, and eyes, especially before washing your hands.

  3. Social gatherings should be avoided as and when possible. However, if any need arises, it is essential to maintain social distancing.

  4. When you cough or sneeze, it is essential to cover your nose and mouth with a tissue. Else use your elbow.

  5. Regularly touched surfaces should be adequately cleaned.

  6. Stay away from sick people, mainly if you belong to the risk group.

  7. Use face masks to cover your mouth and nose when going out.

Can Influenza Vaccine Prevent an Individual From All Strains of Virus?

There are different strains of the influenza virus. Therefore, the antibodies produced from vaccinations or previous infections of one specific virus strain cannot protect an individual from getting infected with a different strain of influenza virus. There is also a reduction in the level of antibodies with time.

Is It Possible to Get COVID and Influenza Together?

Both COVID-19 and influenza are viral infections, and being affected by both at the same time is feasible. Fortunately, preventing the spread of both these infections is also quite similar.


Influenza is a viral infection that can be seasonal. Severe complications, although not always expected, can be seen with flu. Getting the vaccinations annually and following respiratory etiquette can help prevent the occurrence of disease. Reach out to a healthcare provider if you experience flu symptoms to rule out COVID-19 or to get the appropriate treatment.

Last reviewed at:
02 Apr 2022  -  5 min read




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