Influenza or flu is an illness from the influenza virus. It results in symptoms such as body and headaches, respiratory symptoms, fever, and sore throat, which can be severe. Typically, flu occurs in winter, when several people get sick together. It is also called the flu season, usually from October to May in the Northern Hemisphere, and the numbers peak between December and February and is one of the most infectious diseases.

Causes
The influenza virus travels via air in droplets when someone with the virus sneezes, coughs, or talks. Others can inhale these droplets directly, catch the virus or pick the germs from an object like a computer keyboard or telephone and then transfer them to their mouth, nose, or eyes. Typically, people with the virus are transmissible approximately a day before the symptoms and until about four days after it starts. People with weak immune systems and children are contagious for more time.
Influenza viruses keep changing, and new strains appear regularly. But if you have had influenza in the past, you already have the antibodies that combat the specific virus strain.
Hence, when future viruses are similar to the ones encountered before, either via contacting the disease or through vaccination, the antibodies guard against the infection or reduce its severity. However, the antibody levels deplete over time. Further, antibodies from influenzas viruses contacted before do not guard against the newer strains and may be very different from the virus you have had before.

Risk factors
Beyond these causes, some risk factors also heighten your susceptibility or complications associated with influenza. These include:

• Seasonal influenzas are more severe in children below two and adults over sixty-five.
• Chronic illness also aggravates your risk of influenza complications. Some such disorders include diabetes, nervous system diseases, lung diseases, asthma, metabolic disorders, kidney, blood, or liver disease, and airway problems.
• Aspirin use amongst people younger than nineteen may develop Reye’s syndrome if infected with the influenza virus.
• Anti-rejection treatment options, organ transplants, prolonged steroid use, cancer treatments, HIV/AIDS, or blood cancer can weaken the immune system and increase your susceptibility to catching the flu and developing serious complications.
• Those who work or reside in facilities with several others, such as military barracks or nursing homes, are susceptible to developing the flu. People staying in the hospital are also at risk.
• Pregnant people are susceptible to developing influenza complications, especially in their third or second trimester. The risk continues for up to two weeks after they give birth.

Symptoms
Flu symptoms usually appear suddenly, and those with a higher complication risk, such as people with chronic lung disease, must get immediate medical attention. Treatments include antiviral options to lower the symptoms if they commence within a day or two of getting sick. Some of the influenza symptoms include:

• Chills
• Fatigue
• Sore throat
• Sudden high fever onset
• Dry cough
• Joint pain, muscle aches, and headaches
• Runny nose and nasal congestion
• Stomach symptoms, like diarrhea, vomiting, and nausea, may occur but are prevalent in adults and children.

Typically, people with flu recover within one or two weeks, but older adults feel weak for an extended period, even after the symptoms disappear.

Diagnosis
Your doctor will perform a physical exam, check for symptoms and signs of flu, and order a test for influenza diagnosis. When the flu is widespread, you do not need to undergo any testing, as the healthcare professional will diagnose you basis your symptoms. In some cases, your provider may order tests for diagnosing the flu. PCR or Polymerase chain reaction testing is prevalent in labs and hospitals. This test can be performed while you are in the hospital or the health care provider’s office.

Treatment options
Typically, you will require more than rest and a lot of hydration to cure the flu. However, if you have a severe infection, your healthcare provider may recommend a prescription for the flu. They shorten the illness by a day or two and help avoid severe complications.

Lifestyle changes and home remedies
When you acquire the flu, some measures can help ease the symptoms. These are as follows:

• Rest – Get plenty of sleep to help your immune system combat infection. You might have to change your acidity level, depending on the symptoms.
• Drink lots of fluids – Opt for warm soups, juices, and water to avoid dehydration.
• Take pain relievers to combat aches related to influenza.

Further, to restrict the virus from spreading in the community, stay at home and keep your children indoors until the fever remains gone for at least twenty-four hours. Do not be around people until you feel better, and if you leave your home, wear a face mask and wash your hands repeatedly.