Summary

The influenza virus infects your nose, throat, and lungs. The flu is normally worse than a cold.

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

Older people, young children, pregnant women, and people 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 see your doctor early, to find out if you need treatment.

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.

Immunization is your best defense against influenza. Even fit and healthy people should consider getting the flu jab to protect themselves.

The flu spreads quickly from person to person through touch and through the air.

While you’re unwell, stay away from work or school. Look after yourself and your family – rest and fluids are especially important.

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’.

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 diarrhea.

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 women and women 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
• 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, to see if you need treatment (even if you have been seen before).

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 discoloration 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).

Treatment

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 moisturizer 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

Immunization

You can get the vaccine or ‘flu jab’ at your general practice or some pharmacies free you are over 65 or pregnant.  For others with medical conditions that put them at greater risk of influenzas, such as diabetes or heart disease, the vaccine is free from general practices only.  These medical conditions are listed on the Fight Flu website.  

For everyone else, influenza vaccination costs between $25 and $45 depending on the vaccine and provider. Some workplaces also offer a free immunization program for staff.

The vaccine is usually available from April until the end of December but is recommended before winter.

The quadrivalent vaccines available in New Zealand during 2019 provide protection against:

• A/Michigan/45/2015 (H1N1) - like a virus 
• A/Switzerland/8060/2017 (H3N2)-like virus
• B/Colorado/06/2017-like a virus
• B/Phuket/3073/2013 - like virus

For more information, phone 0800 Immune (0800 466 863) or visit Fight Flu.

Immunization if you’re pregnant

Pregnant women are strongly advised to be immunized as pregnancy places a woman at greater risk of complications from influenza.  Influenza immunization is free for pregnant women between March and the end of December but is recommended before winter if possible.

Mothers who receive the influenza vaccine while pregnant can pass protection on to their baby. The vaccine offers protection to infants who would normally be too young (under 6 months) to receive immunization individually.

Visit the Fight Flu website for facts about immunising against the flu when you are pregnant.

Stop the spread of the flu

If you are unwell, stay at home until you are better.

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.

Being prepared for a pandemic

Have a plan and be prepared in case you need to stay at home during a pandemic.

Keep at least a week’s supply of food, tissues, and your usual medicines so you don’t need to make trips out in public.

Make sure you have contact details for friends/family/neighbors so you can call them if you need help.

Think about:

• working from home
• who could look after your extended family if they don’t live nearby (eg, who could deliver groceries or meals to sick family members)
• organizing child-care if your children need to stay home and you must go to work.

If you have an existing medical condition:

• make sure you don’t run out of regular medications
• make sure you take medications for any condition to keep them under good control.