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The flu is an infection. It affects the respiratory system. The flu is caused by a virus.

The Upper Respiratory Tract

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The flu is caused by the influenza virus. Each winter, the virus spreads around the world. The strains are usually different from one year to the next.

The two main kinds of influenza viruses, Type A and Type B.

Someone infected with the virus may sneeze or cough. This releases droplets in the air. If you breathe in infected droplets you can become infected. You can also become infected through touch. If you touch a contaminated surface, you may transfer the virus from your hand to your mouth or nose.

Risk Factors

Factors that increase your chance of the flu include:

  • Living or working in crowded group conditions, such as:
    • Nursing home
    • School
    • Military forces
    • Daycare center

All the remaining factors increase the risk of developing complications from flu:

  • Age: newborn babies and the elderly
  • Women in the third trimester of pregnancy
  • Diabetes]]>
  • Weakened immune systems, such as in:
    • ]]>Cancer]]> patients
    • ]]>AIDS]]> patients
    • People taking immunosuppressive drugs
    • People who have had their ]]>spleen removed]]>
  • Chronic lung, heart, kidney, or blood conditions


Symptoms usually start abruptly. They may include:

  • Fever and chills
  • Severe muscle aches
  • Severe fatigue
  • Headache
  • Decreased appetite, other gastrointestinal symptoms like nausea and vomiting
  • Runny nose, nasal congestion
  • Sneezing
  • Watery eyes, conjunctivitis]]>
  • ]]>Sore throat]]>
  • ]]>Cough]]>
  • Swollen lymph nodes in the neck

You may start to feel better in 7-10 days, but you may still have a cough and feel tired.



The doctor will ask about your symptoms and medical history. A physical exam will be done. Diagnosis of the flu is usually based on symptoms. It also hits communities. the doctor may anticipate more infections.

Samples of nasal secretions or a throat swab can be sent to a lab. This will confirm the diagnosis. Blood tests can be performed, but they take longer and are more expensive.


Treatment may include:

Antiviral Medicines

Antiviral medicines include:

Oseltamivir (and perhaps zanamivir) may increase the risk of self-injury and confusion shortly after taking, especially in children. Children should be closely monitored for signs of unusual behavior.

These medications do not cure the flu. They may help relieve symptoms and decrease the duration of the illness. They must be taken within 48 hours of the first symptoms.

Bed Rest

It is important to get plenty of rest when your body is fighting the flu.


Drink a lot of liquids. This can include water, juice, and non-caffeinated tea.

Over-the-Counter Pain Relievers

These medications are used to control fever and treat aches and pains. Adults can use:

  • ]]>Acetaminophen]]>
  • ]]>Ibuprofen]]>
  • ]]>Aspirin]]>
    • Note: Aspirin is not recommended for children or teens with a current or recent viral infection. Check with your doctor before giving a child or teen aspirin.


Decongestants are available as pills or nasal sprays. If you use a nasal spray, don't use it longer than 3-5 days. You may experience an increase in congestion when you stop using the spray. This is called rebound.

Saline Nasal Sprays

A study found that nasal wash may reduce symptoms, medication use, and school absence. ]]> * 4]]>

Cough Medicines

These include:

  • Over-the-counter (OTC) cough and cold medicines, including decongestants, expectorants, antihistamines, cough suppressants
    • OTC cough and cold products should not be used to treat infants or children less than two years old. Rare but serious side effects have been reported. They include death, convulsions, rapid heart rates, and decreased levels of consciousness. The safety of these products in Serious side effects have also been reported in children aged 2-11 years. Research is still going on for the safety of OTC flu products for this age group. ]]> * 3]]>
  • Prescription cough medicines
  • Cough drops

If you are diagnosed with the flu, follow your doctor's instructions .



Good preventive measures include:

  • Avoid close contact with people who have respiratory infections.
  • Wash your hands]]> often, especially when you come in contact with someone who is sick. Rubbing alcohol-based cleaners on your hands is also helpful.
  • Do not share drinks or personal items.
  • Do not bite your nails or put your hands near your eyes, mouth, or nose.
  • Consider the ]]>flu vaccine]]> . You will need one each year since the exact virus changes.
    • Indications for a yearly flu vaccine, which should be discussed with your doctor:
      • Persons older than 50 years of age
      • Residents and employees of nursing homes and long-term care facilities
      • People with chronic heart and lung conditions
      • People with chronic metabolic disease, kidney problems, hemoglobin abnormalities, or immune system problems
      • Children and teenagers routinely taking aspirin
      • Pregnant women
      • Healthcare providers
      • Household members of high-risk individuals
      • Children age six months to five years
      • Anyone wishing to reduce their risk of getting the flu should consider the vaccine.

For the elderly in the community, vaccine can lead to fewer hospitalizations and deaths. ]]> * 2]]>

Two forms of flu vaccine are available. One is an injectable form and the other is a nasal spray (FluMist). Studies found that the nasal spray led to fewer cases of influenza in a single flu season. Talk to your doctor about which vaccine is the most appropriate for you or your child. ]]> * 1]]>