Things To Know About Flu: Causes, Symptoms And Medicines

Flu Symptoms


Influenza, commonly called flu, is a viral infection that affects the respiratory system comprising the nose, throat, and lungs. In contrast to the common cold which is also a respiratory illness, flu is more severe and caused specifically by the Influenza virus, whereas common cold can be caused by different types of viruses. While a common cold lasts for a few days, the flu can last from a few days to weeks.

Flu has a sudden occurrence causing mild to severe illness and is highly contagious. Flu may result in other severe complications while it constantly weakens the immune system. Although it spreads easily, it is a self-diagnosable condition.


Flu caused by the Influenza virus can spread in various ways, some of which are as follows:

  • By airborne droplets:  while talking, sneezing, or coughing, the droplets which are transferred in the air can potentially infect other people by entering their mouth or nose when they breathe in.
  • Through contaminated surfaces: by touching a contaminated surface such as doorknobs, pen, table, chair, mobile phones, etc. the person gets the germs and the virus thus travels when the hands touch the mouth and nose. 
  • Through body fluids: saliva or phlegm of an infected person can transfer the infection to a healthy person through shared food, drinks, and utensils.
  • By physical contacts such as handshakes and hugs.
  • By sharing things such as clothes, towels, or handkerchiefs of an infected person.

People believe that seasonal flu is not very severe and can cure on its own within a week. But sometimes, flu can be life-threatening in a high-risk group, immunocompromised people, and children in particular.

People with a higher risk of developing flu are:

  • Children below 5 years of age, especially newborns. They are more sensitive as they are in a phase where their immunity has started developing and is not yet strong enough to fight the virus.
  • Older people, above 65 years of age. They are more prone to infection as they have reduced immunity. It is a well-known fact that with age, immunity decreases.
  • People with chronic illnesses such as asthma, liver diseases, diabetes, kidney diseases, heart diseases, etc. The virus infection can result in serious complications for people with chronic health conditions.
  • Underweight as well as obese people. Being underweight is a potential risk factor for getting infected and obesity is known to invite all the poor health conditions like diabetes, high blood pressure, and heart diseases, which themselves are a risk factor.
  • People with a weak immune system.
  • Pregnant women. Flu can be dangerous during pregnancy as it may lead to various complications such as premature labor and delivery.
  • Staff working in health care facilities are more prone to a flu-infection as they are surrounded by all kinds of illnesses.


Symptoms may appear in 1 to 4 days after exposure to the virus. Initially, the person may not feel good in general and may experience a loss of interest in activities. It appears like a common cold, though it can be diagnosed and differentiated through the following symptoms:

  • Period of chills and sweats;  flu fever can range from as low as 100°F to as high as 104°F
  • Hoarse, dry, and sore throat
  • Runny or congested nose
  • Itchy nose and ear
  • Dry cough or cough with phlegm
  • Muscle pain and body aches; flu-related pain can often be severe and a person may feel terrible pain even while performing basic tasks.
  • Fatigue; though it is a common symptom of several illnesses, is more severe when associated with flu. Extreme weakness and tiredness interferes with normal activities.
  • Burning, tearing, or itchy eyes
  • Loss of taste and smell
  • Headache
  • Loss of appetite
  • Dehydration
  • Swollen lymph nodes

It is important to note that not everyone with flu will have all the mentioned symptoms. Some symptoms such as weakness and tiredness can be felt for a few days even after the flu symptoms have subsided. 

Symptoms of flu which require immediate medical care:

  • Shortness of breath
  • Vomiting
  • Earache or discharge from the ear
  • Faintness or dizziness
  • Persistent pressure and pain in the chest
  • Worsening of chronic medical conditions
  • Recurring of high fever
  • Bluish skin and lips
  • Severe dehydration 

Complications of flu

Flu weakens the immune system of the body and in some cases, the body may not be able to fight the virus, that is when the flu transforms into a much worse condition called Pneumonia, leading to inflammation of the lungs. Pneumonia is a serious complication of the flu which may lead to death, if not treated immediately. The following are some moderate complications of flu:

  • Sinus and ear infection
  • Bronchitis, inflammation of the lining of bronchial tubes
  • Myocarditis, inflammation of the middle layer of the heart wall
  • Encephalitis, inflammation of the brain
  • Myositis, inflammation in muscles


Flu can be treated by taking some measures which can ease the symptoms and provide relief. Those measures are as follows:

  • Drink plenty of warm liquid: lukewarm water, hot tea, soups, and drinks will prevent dehydration along with relieving the pain of a sore throat. Hydration helps in the loosening of thick clogged mucus in the lungs. Fluid thins out the thick mucus that builds up with flu. Avoid drinks such as coffee, cold drinks, fruit juice, and alcohol as they can dehydrate the body. 
  • Take enough rest. It helps the immune system to work better and the body feels energetic. Thus, a flu patient recovers faster.
  • A person can take steam or can use a humidifier for the congested nose. Saline nose drops and sprays can provide much-needed relief.
  • Gargling with salt water can ease a sore throat.
  • Consuming a healthy diet reduces the weakness of the body by proving nutrients.


The symptoms of flu cure on their own in 5 days or so without medical care but if it persists for long the person can take analgesics, antiviral, decongestant, or anti-inflammatory drugs, after consulting a doctor. Paracetamol is the drug of choice which may help in relieving some symptoms. Other common medications are Acetaminophen, Ibuprofen, and Naproxen which help in relieving pain, reducing fever, and mild inflammation. 

Common antiviral medications that doctors may prescribe are Zanamivir (Relenza), Peramivir (Rapivab), and Oseltamivir (Tamiflu). They can limit the complications of flu and work best if taken within 48 hours of the onset of symptoms. These drugs can ease the symptoms hence reducing the span of the illness. 

The use of Aspirin should be avoided in the case of flu. 


Annual vaccinations and simple hygiene measures can prevent the onset of a flu. But one should not overlook the problem. If the symptoms are severe, consulting a doctor is mandatory.