Influenza
Influenza A & B viruses
in · floo · EN · zuh
A contagious respiratory virus, commonly called the flu. It spreads easily from person to person and can cause anything from a few days of feeling unwell to serious illness, especially for those at higher risk.
What is influenza?
Influenza, usually called the flu, is a contagious respiratory illness caused by influenza viruses (mainly types A and B). It infects the nose, throat, and lungs. The viruses change from year to year, which is why the flu comes back each season and why protection needs to be renewed.
Symptoms to watch for
Flu symptoms often come on quickly and may include:
- Fever or feeling feverish, and chills
- Cough and sore throat
- Runny or stuffy nose
- Muscle or body aches and headache
- Tiredness, which can be significant
- Some people, especially children, may have vomiting or diarrhea
Who is at higher risk?
Anyone can get the flu, but serious illness is more likely for:
- Adults 65 and over
- Young children
- People who are pregnant
- People with heart, lung, kidney, or other chronic conditions, including diabetes
- People with a weakened immune system
How does it spread?
The flu spreads mainly through respiratory droplets when an infected person coughs, sneezes, or talks. It can also spread by:
- Breathing in droplets from someone nearby
- Touching a surface with the virus on it, then touching the eyes, nose, or mouth
- Close contact with someone who has the flu
Get the annual flu shot
The flu vaccine is the single best way to protect yourself and the people around you. Because the viruses change each year, a new shot every fall keeps your protection up to date.
- Recommended every year for almost everyone 6 months and older
- Especially important for higher-risk groups and the people who care for them
- Lowers your chance of catching the flu and of becoming seriously ill
More ways to protect yourself
Alongside the flu shot, simple daily habits go a long way toward stopping the spread:
- Clean your hands often with soap and water or an alcohol-based hand sanitizer. Both work well against flu viruses.
- Cover your coughs and sneezes with a tissue or your sleeve, not your hands
- Avoid touching your eyes, nose, and mouth
- Stay home when you are sick to avoid passing it on
- Clean and disinfect frequently touched surfaces
- Wear a well-fitted medical mask if you cannot distance from others, or if you have to leave the house
Why precautions are necessary
The flu spreads easily from person to person, and people are contagious before and after symptoms appear. Staff and visitors can pass it to patients who are already unwell, so extra care is taken during flu season.
Droplet and Contact precautions may include
- A private room when one is available
- Staff and visitors wearing a mask in the room
- Gloves and gowns for some care activities
- Limiting movement outside the room
- Hand hygiene before and after contact
For patients
- You may be asked to stay in your room and wear a mask when others are present
- Cover your coughs and sneezes, and clean your hands often
- Follow your care team's instructions on precautions
For visitors
- Do not visit if you have flu-like symptoms
- Clean your hands before and after visiting
- Wear a mask or other PPE if you are asked to
- Consider getting your flu shot before visiting during flu season
Cleaning helps
- The flu virus can live on surfaces for up to 48 hours, so high-touch surfaces need to be cleaned and disinfected frequently
- Hospital grade cleaning and disinfection products are used to inactivate and remove viruses
- Shared equipment is cleaned and disinfected between uses
Common high-touch surfaces:
Treatment & recovery
- Most people recover on their own in about a week to two with rest and fluids
- Antiviral medicine may be prescribed for some people, and works best when started early
- Treat fever and aches as advised by your care team
- Antibiotics do not work on the flu, because it is caused by a virus
When to seek care
Get medical help right away if you or someone you care for has:
- Trouble breathing or shortness of breath
- Chest pain or pressure
- A high fever that will not come down, or symptoms that get worse
- Confusion, or signs of dehydration
Looking after yourself at home
Rest and fluids
Get plenty of rest and drink lots of fluids. Most people feel better within a week or two.
Stay home
Stay home until you are fever-free for at least 24 hours without fever-reducing medicine, so you do not spread it to others.
Limit the spread
Cover coughs, clean your hands often, and avoid close contact with others at home. Do not share cups, utensils, or towels.
Protect the household
Encourage everyone in the home to keep up good hand hygiene and to get their flu shot when it is available.