HONOLULU (April 6, 2018) - The flu is a contagious illness caused by the influenza virus, and during this year's flu season, more emergency room visits, hospitalizations, and deaths have occurred nationwide, especially among older people and very young children.

Many do not know that seasonal influenza viruses circulate in Hawaii year-round, but most commonly during the fall and winter months, with activity usually beginning in October and can last until May.

Peak flu activity in the U.S. occurs from December through February. However, the exact timing and duration of each flu season vary from year to year.

The flu is spread mostly by droplets made when someone with the flu coughs, sneezes or speaks. The droplets land on the mouth or nose of people nearby and infect them. Sometimes people can get the flu from touching something that has the flu virus and then transmitting it to themselves by touching their own eyes, mouth or nose.

Symptoms of the flu include fever, chills, cough, sore throat, runny or stuffy nose, body aches, headaches, weakness, vomiting, and diarrhea.

People with the flu may pass on the flu to others one day before their symptoms even begin, and up to seven days after becoming sick; though they are most contagious in the first three to four days of their illness.

Some people can be infected with the flu but have no symptoms and still spread the virus to other people. Once someone has been exposed to the flu, they typically develop symptoms in one to four days.

The flu and the common cold are illnesses with similar symptoms, but the common cold is usually milder than the flu. Colds, unlike the flu, usually do not result in serious health problems. People who have colds more commonly have a stuffy or a runny nose.

Most people with mild illness do not need to seek medical care or antiviral medications. People may feel better after taking Tylenol or Ibuprofen if they have a fever. Drink lots of fluids as you will lose more water due to an increase in respiratory rate with a fever.

Most people with the flu recover, but some people will have a more severe illness or complications. Complications of the flu include pneumonia, bronchitis, sinus infections and ear infections. The flu can also cause chronic medical problems (such as asthma or heart failure) to worsen.

Some medical conditions which may increase flu complication rate include asthma, heart disease, kidney disease, liver disease, diabetes, people with extreme obesity (body mass index over 40), and people with a weak immune system (due to medications or people with cancer or HIV).

Flu-related deaths occur one to two weeks after the person's infection because the person develops a secondary bacterial infection or because the flu aggravates a chronic illness.

People who are at high-risk for developing flu complications include children younger than five years old (especially kids under two years old), people more than 65 years old, pregnant women (and up to two weeks postpartum), nursing home patients, Native Americans, and people with certain medical conditions.

If you are in a high-risk group or are very sick, you should seek medical care immediately. Please seek emergency care if you are having trouble breathing, dizziness, persistent vomiting, chest pain, or abdominal pain.

Bring your child to the doctor if they are unable to eat or take-in enough fluids, not interacting normally, having a fever with a rash, having trouble breathing, crying without tears, or urinating less wet diapers than usual.

People who are sick with the flu should stay at home and practice proper hand hygiene, washing with soap and water for at least 20 seconds to avoid spreading their illness. Also avoid sharing utensils, linens, and dishes with people who are sick.

The Centers for Disease Control recommends a yearly flu vaccine to prevent the flu to protect against three to four different viruses. Unfortunately, flu vaccines do not work as well against the H3N2 viruses which have been the most common this year.

But even with reduced vaccine effectiveness, the vaccine can still prevent some flu illness. There is also some data to suggest that if someone does get sick after the vaccine, their condition may be milder.

It is good to remember that people can always contract the flu, even during off-season months; so it is essential to learn more about the flu, and take actions to prevent from contracting the illness.