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know about the flu virus

Everything you need to know about the flu virus!

Influenza, commonly known as the “flu”, is an extremely contagious respiratory illness caused by the influenza type A or type B virus. It is a viral infection that attacks the respiratory system (nose, throat, and lungs).

Three or four of the most common types of influenza viruses that affect humans are type A, type B, and type C. Type D is not known to infect humans but is experimentally believed to have the potential to do so.

Fast facts on influenza

•    Antibiotics are not effective against the flu but some antiviral drugs can be used for treatment.

•    The best method for flu prevention is annual vaccination.

•    The flu vaccine is not suitable for some people, for instance, those who are allergic to chicken eggs.

•    Approximately 45% of the total American population is affected by the flu at some stage of their life.

Is there a difference between a cold and the flu?

Both the common cold and the flu are contagious viral infections of the respiratory tract. The symptoms are more or less similar but the symptoms of the flu are more severe. A cold may drag you down a bit, but influenza will make you shudder at the very thought of getting out of bed!

Some common symptoms of a cold and the flu include congestion, sneezing, sore throat, headache, coughing, and chest discomfort.  The flu commonly leads to high-grade fever, body pain, fatigue, and weakness.

Complications from a cold are relatively minor, but the flu can lead to a life-threatening illness such as pneumonia!   

There are more than 100 different strains of a cold virus known and new strains evolve every couple of years.  Both the common cold and the flu are viral infections and antibiotics cannot treat them.  As mentioned, there are antiviral medicines available to treat the flu–a cold cannot be treated by antibiotics?

People, who are at high risk of developing complications from what? include:

•    Young children under the age of 5

•    Adults older than 65 years of age

•    Pregnant women especially after parturition

•    Residents of nursing homes and other daycare facility centers

•    People with a weak immune system

•    People with any chronic illness such as cardiovascular disease, renal disease, diabetes, asthma and, liver disease

•    Obese individuals whose body mass index (BMI) is 40 or higher.

Symptoms of Influenza

In the initial stages, the symptoms of the flu will be similar to the common cold with a runny nose, sore throat, and sneezing. Common signs and symptoms of the flu include:

•    Fever over 100 Fahrenheit (38 Celsius)

•    Muscle pain

•    Chills and sweats

•    Headache

•    Fatigue and weakness

•    Dry and persistent cough

•    Nasal congestion

•    Sore throat

Complications of the Flu

Seasonal influenza does not seriously affect young and healthy individuals, although you may feel miserable while you have it, the flu usually goes away in a week or two with no lasting effects except weakness.

How to control the spread of infection

The Influenza vaccine is not one hundred percent effective so it is important to adopt preventive measures to limit the spread of infection.

Wash your hands: Wash your hands properly with soap after using the toilet, try to use alcohol-based sanitizers if soap and water are not available. Thorough and frequent hand washing is an effective way to prevent the spread of infections.

Contain your cough and sneeze:  Try to cover your mouth while sneezing or coughing. To avoid contaminating your hands, use a napkin or handkerchief.

Avoid crowds:  The flu virus spreads easily wherever people aggregate, in schools, offices, auditoriums, daycare centers, public transportation, etc. Trying to avoid crowded areas in peak flu season will reduce your chances to catch the infection and if you are sick, stay at home for at least 24 hours to minimize the chance of infecting others.

Diagnostic tests

There are a number of tests to diagnose influenza or the flu virus. One is called rapid molecular assay in which a specimen is collected from the upper respiratory tract (mucus) using a nasal swab or nasopharyngeal swab. The tests should be performed within three to four days of symptoms onset because infections of the upper respiratory tract spread to other parts of the body including vital organs in a spiral direction.

Treatment of Influenza

Patients of influenza are advised to rest, drink excessive fluids, and avoid the usage of alcohol, tobacco, and other drugs. The use ibuprofen (paracetamol) is prescribed to relieve fever and associated muscle pain.


Two classes of antiviral drugs are used against influenza. These include neuraminidase inhibitors (oseltamivir, zanamivir, laninamivir, and peramivir) and M2 protein inhibitors (derivatives of the adamantine family).

Prevention of Influenza

The Centers for Disease Control and Prevention (CDC) recommends annual flu vaccination for individuals aged six months or older.

The vaccine provides immunity against three or four common strains of influenza viruses. The vaccine is readily available in all primary care centers in two different forms. The vaccine can be taken in the form of an injection or nasal spray.

The spray is questioned for its effectiveness by the medical communities and is relatively less common. The current version of the spray is expected to be more effective, according to the CDC but still, the nasal spray is not recommended for some people, including pregnant women, children, patients with asthma or wheezing cough, and the elderly.

The common flu vaccine contains a very small amount of egg protein. So people who are allergic to eggs, need the proper supervision from a medical practitioner to get vaccinated against influenza.


This blog is for informational & educational purposes only, and does not intend to substitute any professional medical advice or consultation. For any health related concerns, please consult with your physician, or call 911.

Read this to learn more about influenza: Everything You Need To Know About The Flu Virus | Why Should You Get A Flu Shot | Influenza Flu Vaccine | Why You Need A Flu Shot This Year | What Is Influenza

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Medically Reviewed

Last reviewed by Dr. Syra Hanif, M.D. on 04/12/2019

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  • About The Author

    Dr. Syra Hanif M.D.

    Board Certified Primary Care Physician

Dr. Syra Hanif is a board-certified Primary Care Physician (PCP) dedicated to providing compassionate, patient-centered healthcare.

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