What is Flu of Influenza?
Influenza or “flu,” is a common viral infection that affects the respiratory system, including your nose, throat, bronchial tubes and lungs. Influenza is distinctly different from the common cold. It is caused by a different virus and produces symptoms that are more severe. The flu is very contagious – spreading easily from one person to the next. Influenza virus is spread by inhaling droplets that have been coughed or sneezed out by an infected person or by having direct contact with an infected person's nasal secretions. While most cases run their course in one to two weeks, life-threatening complications such as pneumonia are possible, especially in the elderly or people with chronic illnesses.
Signs and Symptoms of Flu
Symptoms can begin suddenly from 1 to 4 days of exposure to infection. Flu symptoms would start as a mild respiratory disorder including runny nose, sneezing and sore throat. Eventually cough would worsen and bring up phlegm (sputum). Fever is common during the first few days and a general feeling of weakness, tiredness, aches and pain would also be some of the symptoms.
Other common signs and symptoms of the flu include:
- Fever over 101°F. (about 39° C and over).
- Chills and sweats.
- Headache
- Dry, nonproductive cough.
- Muscular aches and pains, especially in your back, arms and legs.
- Fatigue and weakness
- Sneezing, runny nose or nasal congestion
- Loss of appetite.
- Diarrhea, vomiting and nausea in children.
Cause of Flu or Influenza
Influenza or “flu,” is caused by viruses that are spread in the air when an infected person sneezes, talks or coughs. Viruses are transferred through inhalation of virus laden droplets suspended in air, or can be picked up from an object such as phone, keyboard and other commonly touched items then transferred to the eye, nose or mouth.
The flu is caused by three types (strains) of viruses - influenza A, B and C. Type A is responsible for the deadly influenza pandemics (worldwide epidemics) that strike every 10 to 40 years. Type B can lead to smaller, more localized outbreaks that generally occur every three to 15 years. And either types A or B can cause the flu that circulates almost every winter. Type C is less common and causes only mild symptoms.
Prevention of Flu or Influenza
The best way to prevent contracting influenza or “flu” is to have a flu vaccine. But since there are many types of influenza virus, and because they change over time, a new flu vaccine is offered every fall. You have to consult your doctor about the flu vaccine that is best for you.
