Influenza

Influenza – or the flu – is a virus that spreads quickly from person to person. Symptoms include fever, chills, aches, runny nose, a cough and stomach upset. Immunisation is your best defence against the flu.

Summary

Influenza can be caused by different strains of the influenza virus. (Symptoms for different types of flu are the same.) The seasonal influenza vaccine is altered most years to cover the particular strains of the virus that are circulating each year. When a new (novel) strain of the flu virus emerges that infects many people in a very short time, it is called a ‘flu pandemic’.

The influenza virus infects your nose, throat and lungs. The flu is normally worse than a cold and spreads quickly from person to person through touch and through the air.

Symptoms of influenza come on suddenly and can include fever, chills, muscle aches, runny nose, cough and stomach upsets.

Immunisation is your best defence against influenza (flu).

As New Zealand reconnects with the world, we are bringing to an end the border arrangements that both protected us against Covid-19 and kept a range of other diseases out of New Zealand, including influenza.

We have had very little influenza circulating in our communities since the pandemic began and this means our community immunity is lower than usual.

In climates such as New Zealand’s, you’re more likely to get the flu in winter. Some people get very sick – in most years, influenza hospitalises thousands of people, and some lose their lives to it.

We are expecting to see some of the new strains of the flu virus that have emerged in the Northern Hemisphere winter. There’s no residual immunity to these new strains.

Older people, young children, pregnant people, and those with certain medical conditions are at a higher risk of developing serious complications from influenza, such as pneumonia. If you’re at higher risk, it is important to call your doctor early, to find out if you need treatment.

In severe cases it can mean a hospital stay. It can sometimes be fatal – around 500 people die from the flu in a typical year.

This winter there is the very real possibility of having flu and Covid-19 within a short space of time. This can lead to very serious illness and high mortality rates.

If you do catch flu, while you’re unwell, it’s important that you stay away from work or school. Look after yourself and your family – rest and fluids are especially important.

The symptoms of influenza can be the same or similar to the symptoms of COVID-19. If you are sick, stay home. Call your health provider or Healthline and follow their advice. They may advise you to have a COVID-19 test, and self-isolate while you wait for the results.

It is also important to seek medical advice early if you are concerned, and especially if there are any danger signs, even if you have been seen before. Other serious conditions can also look like the flu, including meningococcal disease.


Find out more from the Ministry


Related websites

Flutracking
A new monitoring system that enables people to help us track flu across New Zealand.

Kidshealth
Developed by the Starship Foundation and the Paediatric Society of New Zealand.

Safe Travel website
Advice for travellers from the Ministry of Foreign Affairs and Trade.

Symptoms

Signs and symptoms of influenza can include:

  • fever (a temperature of 38°C or higher)
  • cough
  • sore throat
  • runny or stuffy nose
  • body aches
  • headache
  • chills
  • stomach upset, vomiting or diarrhoea.

It may take between 1–4 days to feel symptoms after you catch influenza.

The worst symptoms usually last about 5 days, but coughing can last up to 2–3 weeks.

High risk groups

People at higher risk of developing complications if they get influenza include:

  • pregnant people 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 people aged 55 and over
  • people aged 65 years or over
  • very young children, especially infants (under 1 year).
If you are at higher risk, or are concerned about your symptoms, it is important to seek advice early from your doctor or Healthline (ph 0800 611 116), to see if you need treatment (even if you have been seen before).

If you are at higher risk, or are concerned about your symptoms, it is important to seek advice early from your doctor or Healthline (ph 0800 611 116), to see if you need treatment (even if you have been seen before).

Māori and Pacific people aged 55 and over, other people aged 65 and over, pregnant people, those with certain chronic conditions and young children with a history of severe respiratory illness are eligible for free influenza immunisation. For more information on the flu vaccine visit the Ministry’s flu vaccine page.

 

Danger signs

Seek urgent medical advice if you have:

  • a high fever that doesn’t come down, especially if you are pregnant
  • chills or severe shaking
  • difficulty breathing or chest pain
  • purple or bluish discolouration of your lips, skin, fingers or toes
  • seizures or convulsions
  • signs of other serious conditions, such as meningococcal disease (which may include severe headache, sleepiness, vomiting, stiff neck, dislike of bright lights, and sometimes a rash).

Look out for signs of dehydration such as dizziness when standing, and not passing urine regularly.

If a person you are caring for is less responsive than normal, unusually quiet, or confused, you should call a doctor urgently.

It is also important to let your doctor know if you were starting to feel better, then get worse.

Danger signs for babies and young children

Call a doctor if your baby or child’s breathing is fast or noisy or if they are wheezing or grunting. Check if the area below the ribs sucks inward (instead of expanding as normal) as they breathe in.

You should get help if your baby or child is:

  • very pale
  • drowsy or difficult to wake
  • severely irritable, not wanting to be held
  • limp or unable to move
  • if a baby has dry nappies or no tears when they are crying, it means they are dehydrated. It is important to contact a doctor
  • if they have signs of other serious conditions, such as meningococcal disease (which may include severe headache, stiff neck, dislike of bright lights, and sometimes a rash, but in very young children are often non-specific such as sleepiness and vomiting).

If you have any worries about yourself or someone you are caring for, call Healthline (0800 611 116) for advice or see a doctor, even if you have called or been seen before.

Treatment

Phone Healthline (0800 611 116) or your doctor if you are concerned or if you:

  • feel a lot worse, or you are not getting better after a few days
  • have an existing health condition or are in a high risk group (see Symptoms)
  • are pregnant
  • are taking any medication that affects the immune system
  • are looking after someone with influenza and you are in a high risk group

If clinically indicated, your doctor may recommend antiviral medications. Take them as directed.

Caring for yourself and others

If you are unwell, stay at home and rest ideally/preferably in a separate, well ventilated room away from other people.

It is important to drink small amounts of fluids often.

Antibiotics only work against bacterial infections, not the viral infections that cause influenza.

Carefully read and follow the labels on any medication and contact your doctor or pharmacist if you have any questions

You can also:

  • reduce fever by using a damp cloth on your forehead, washing the arms and body with a cool cloth, bathing in slightly warm water
  • take appropriate medicines to relieve discomfort and fever if necessary.
  • It is especially important to reduce fever if you are pregnant.
  • gargle a glass of warm water and/or suck sugarless hard sweets or lozenges to help with sore throats
  • shower or bathe regularly and keep bedding and nightwear clean and dry
  • use skin balm or moisturiser to stop your lips from cracking.

Know the danger signs that mean you should seek urgent medical attention (see Symptoms).

Any child younger than 3 months who has a fever should see a doctor

Caring for babies and children

When a baby or child has influenza, it is important to do the following:

  • keep the child at home resting until they are well.
  • care for the child in a separate, well-ventilated room away from other people.
  • increase the frequency of breastfeeding or the amount of other fluids they drink. If your child will not take fluids or is drowsy, don’t force them. Seek medical advice immediately.
  • reduce fever by using a damp cloth on their forehead, washing their arms and body with a cool cloth, bathing them in slightly warm water.
  • give paracetamol or ibuprofen if they have pain or discomfort in the dose recommended on the package (unless your doctor says otherwise). Aspirin should not be given to children under 14 years of age.

Saltwater drops (saline) can be used to treat a stuffy nose.

Prevention

Get a flu jab

Your best defence against flu is to get a yearly flu jab and follow basic hygiene practices.

Getting a flu jab is your best defence from the flu this winter. They’re available from April 2022 and are free for those most likely to get very sick.

In 2022, flu vaccinations are free for: 

  • pregnant people 
  • people aged 65 years and over 
  • Māori and Pasifika aged 55 years and over 
  • people who have a long-term medical condition like diabetes, asthma, or a heart condition (ages 6 months+)
  • children 4 years old or younger who have been in hospital with respiratory illness such as asthma.  

If you’re not eligible for a free flu jab, and not covered by an employer-funded programme, it costs between $25 and $45 depending on the vaccine and provider.

About the flu vaccine

Follow basic hygiene practices

  • Wash your hands regularly for at least 20 seconds and dry them for 20 seconds – or use an alcohol-based hand rub.
  • Avoid touching your eyes, nose, and mouth.
  • Don’t share drinks.
  • Avoid crowded places.
  • Cover your mouth and nose with a tissue when you cough or sneeze – then put the tissue in a lined bin.

In this section

  • As Aotearoa emerges from its bubble, there’s a much bigger chance of catching the flu. Getting a flu jab is your best defence. They’re available now and are free for those most likely to get very sick. Read more
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