A cold or the flu? Or COVID-19?

Maremare, rewharewha, mate korona?

Having a cold or the flu is common during the short, cold days of winter. We now have COVID-19 to think about as well. A cold is usually a mild illness but the flu and COVID-19 can be serious, so it’s good to know the difference. If you have cold or flu symptoms get a test for COVID-19.

Coldsinfluenza (the flu) and COVID-19 all affect your airways and how you breathe. This means they are easily confused with one another. While a cold is not usually serious, the flu and COVID-19 can be. 

If you have symptoms, get a COVID test and if you are (or think you might be) positive, get somebody else to pick up cold and flu medicines for you, don't go into a pharmacy yourself. 

Could it be COVID-19?

Symptoms of COVID-19 are similar to having a cold or the flu.

Symptoms of COVID-19 can include:

  • a cough
  • a fever (temperature of 38˚C or higher)
  • shortness of breath
  • a sore throat
  • sneezing and runny nose
  • temporary loss of smell
  • upset stomach, possible with diarrhoea (runny poo) or vomiting (being sick).

Read more about COVID-19 symptom timeline – what to expect.  

If you have any of these symptoms, get a test or phone Healthline's dedicated COVID-19 number 0800 358 5453. You may be eligible for free rapid antigen test (RAT) kit to use at home.  

Vaccination is your best defence against COVID-19 and the flu. Learn more about COVID-19 vaccines and the flu vaccine. 

What's the difference between a cold and the flu? 

See also symptoms of COVID-19.

A cold

Influenza (the flu)


  • Mild illness lasting 1–2 weeks.
  • Some symptoms, such as a cough, may continue for a few weeks.


  • Moderate to severe illness with sudden onset of symptoms lasting 7–10 days.
  • The cough and tiredness can last for weeks after the rest of the illness is over.


Early signs include:

  • a sore throat
  • sneezing
  • running nose
  • mild fever.

After a few days, snot usually becomes thicker and may turn a greenish or yellowish colour.

Muscle pain is uncommon.

Mild headache (congested sinuses).

Sometimes a cough.


Sudden onset of:

  • fever (temperature of 38°C or higher)
  • shivering
  • muscle aches
  • debilitating tiredness
  • headache (may be severe).

Dry cough may become moist.

Bed rest is necessary.


Washing your hands frequently.

Not coughing over other people.


Influenza (flu) vaccine (free for those in high-risk groups).

Washing your hands frequently.

Not coughing over other people.

Possible complications

Sinus congestion

Ear infection

Possible complications


Pneumonia – can be life-threatening

When to seek advice for colds or the flu

You can treat most colds and flu-like illnesses with rest and self-care at home, but you need to know when to seek medical help.

Phone your medical clinic for advice if you:

  • are not getting better
  • are pregnant
  • have diabetes or a health condition affecting your breathing, heart or immune system
  • are aged 65 or older
  • have a sore throat and are Māori or Pasifika aged 3–35 years
  • are concerned or not sure what to do.

If you are unsure what to do phone Healthline free on 0800 611 116 or your doctor for advice.

When to seek immediate medical help

If you have any of the following signs you may be seriously unwell and need emergency care: 

  • difficult or painful breathing
  • bluish lips or tongue
  • chest pain
  • coughing up blood
  • severe shaking, rigors
  • confusion or difficult to wake
  • stiff neck
  • rash with purple or red spots or bruises
  • clammy skin
  • not urinating or dark coloured pee
  • feeling faint or passing out (fainting).

Phone 111 or go to the hospital emergency department right now. Do not delay.

Self-care for colds and the flu

Rest at home so you don’t spread bugs.
Drink plenty of fluids, warm lemon and honey drinks or soups to avoid dehydration (honey is not safe for children under one year).
If you have a sore throat, suck a teaspoon of honey or gargle with salt water. Adults can also try using a gargle, throat spray or pain-relief (anaesthetic) lozenges.
For a blocked or runny nose ask your pharmacist about decongestants and saline nasal sprays.
For a cough sip a lemon and honey drink or ask your pharmacist about cough lozenges or medicines that may be suitable for you. Cough medicine doesn’t cure a cough but may give you some relief from it.
For aches and pains try paracetamol OR cold and flu medicines (check doses carefully and ask your doctor or pharmacist what is safe for you).
Avoid antibiotics, they can’t cure colds, flus or most coughs as these are caused by viruses.

Avoid catching and spreading bugs

Take care of your health and protect your whānau and community.

  • Wash your hands for 20 seconds and dry them well.
  • Cover your coughs and sneezes.
  • Avoid touching your face.
  • Don’t share personal items such as cups, food utensils or towels.
  • Clean and disinfect surfaces often, like doorknobs.
  • Stay home if you are sick and avoid close contact with others.

Learn more about preventing the spread of COVID-19.

Keep well this winter

Get the flu vaccine each year – it might be free for you.
Keep your immune system strong – be active, eat healthy food, be smoke-free and get plenty of sleep.
Stay warm – heat your home to at least 18°C.
Quit smoking – smokers get more colds, symptoms are worse and they last longer.

Learn more

Colds Health Navigator NZ
Influenza Health Navigator NZ
Antibiotic resistance Health Navigator NZ
Influenza (flu) topics Health Navigator NZ

Reviewed by

Dr Sharon Leitch is a general practitioner and Senior Lecturer in the Department of General Practice and Rural Health at the University of Otago. Her area of research is patient safety in primary care and safe medicine use.
Credits: Health Navigator Editorial Team. Reviewed By: Dr Sharon Leitch, GP and Senior Lecturer, University of Otago Last reviewed: 21 Mar 2022