Flu (influenza) Te rewharewha
The flu (influenza) is a virus that spreads quickly between people. Flu causes symptoms like a fever, runny nose, cough or upset stomach. There can be different types or strains of flu that can make you sick each year.
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How flu spreads
Flu (influenza) spreads quickly from person to person through touch and through droplets in the air. This includes:
- direct contact with people who have flu
- contact with surfaces that have the flu virus on them
- coughing
- sneezing
- talking.
You are most likely to get the flu during 'flu season' — May to October in Aotearoa New Zealand.
Adults are most likely to be contagious in the first 3 to 5 days of illness. Young tamariki can be contagious for more than 5 days.
Symptoms of flu
The flu virus infects your nose, throat and lungs. It is normally worse than a cold.
It can take between 1 to 4 days to feel symptoms after you catch flu. The worst symptoms usually last about 5 days, but coughing can last up to 2 to 3 weeks.
Symptoms of flu start suddenly and can include:
- fever or feeling feverish
- chills
- muscle or body aches
- headache
- runny or stuffy nose
- cough
- sore throat
- upset stomach, throwing up (vomiting) or runny poos (diarrhoea).
Illnesses with similar symptoms
Flu symptoms can be similar to other illnesses like COVID-19 or meningococcal disease. If you suspect someone in your whānau has meningococcal disease, seek urgent medical attention.
Complications of flu
Some people get very sick with flu. It can cause serious complications, like chest or sinus infections.
In severe cases people need to stay in hospital. Around 500 people die from the flu each year.
People at higher risk of getting complications from flu include:
- pregnant women and those who have just given birth
- people with an ongoing health condition — like asthma, diabetes, cancer, a heart or lung condition, and conditions that affect the nervous or immune systems
- significantly overweight people
- Māori and Pacific peoples aged 55 and over
- people aged 65 years or over
- pēpi and tamariki, especially under 5 years
- people with serious mental health or addiction issues.
Diagnosing flu
Healthcare providers do not usually test for flu. They usually diagnose you based on your symptoms.
Your healthcare provider may do a physical exam and look for signs and symptoms of flu. They might order tests to make sure it is not a different illness if you have serious symptoms.
If you do catch flu, it is important that you stay away from work or school while you are unwell.
Treating flu
There is no specific treatment for flu. Antibiotics only work against bacterial infections, not the viral infections that cause flu.
Most people will get better by staying home and resting.
Self care with flu-like illness
If you are unwell, stay at home and rest in a separate, well-ventilated room away from other people if you can.
You may feel pressure to be at work, but you will generally feel worse if you go in. You are also most likely to pass your cold to others during the first 2 to 3 days, so colleagues may thank you for staying away.
Your body may need more water if you have a fever. Being dehydrated will make you feel much worse so drinking plenty of water can help.
This can help to relieve fever, aches, sore throats, earache and headaches. Carefully follow the instructions on the label about how much medicine you should take and how often you should take it. It is important not to take more than the maximum dose.
These come as tablets or nasal sprays and can help with headaches and a blocked nose. But you should not use them for more than 3 to 4 days. Decongestants can cause side effects, such an irritated nose, a dry mouth and headaches. Speak to a pharmacist before using a decongestant, especially if you are taking any other medicine.
This may make congestion better for a while and does not have the same side effects as decongestants. Having a warm shower or bath before bed may also help, as can using a humidifier in your bedroom.
These can help make a sore throat feel better, but they may not be any more effective than simple pain relief medicine like paracetamol.
There are lots of cold and flu medications available over the counter. Read the labels carefully because they are often expensive versions of simple pain relievers or decongestants. Speak to a pharmacist if you are not sure what to take or if you are taking other medication, especially if you have any other health condition or are pregnant, as it may be best that you do not take these medications.
Preventing flu
The flu virus changes often. This means the vaccine has to be adjusted each year to match the new strains of the disease. Your best defence against flu is to get a yearly flu vaccine and follow basic hygiene practices.
Some people can get flu vaccines for free. Find out about flu vaccines and when to get them.
Other ways to avoid flu
You can also protect yourself and your whānau in other ways.
- Wash your hands regularly for at least 20 seconds, and dry them for 20 seconds — or use an alcohol-based hand rub.
- Do not share drinks.
- Avoid crowded places.
- Cover your mouth and nose when you cough or sneeze.
Flu in babies and children
The flu can be a serious and sometimes life-threatening infection for pēpiand tamariki. The KidsHealth website has information on flu in pēpi and tamariki, and when to get medical help.
Flu in children — KidsHealth