The potentially deadly Australian flu has spread to the UK, with health bodies reporting a large rise in cases.
In Ireland, the Irish Health Service Executive says a number of people have died from Australian flu.
And Public Health England says a growing numbers of cases have been reported in the past two weeks by GPs and hospitals.
Among those hit by the outbreak is millionaire sportsman Conor McGregor. The 29-year-old UFC fighter said he had been left "shaking in bed the past two days" by the nasty illness.
The strain, known as H3N2, has already caused hundreds of deaths Down Under and has affected up to 170,000 people. People are being urged to get a flu jab to protect themselves.
The flu is a subtype of influenza A and mainly affects pregnant women, the elderly and children.
Those with health conditions are also at risk of the bug which can lead to pneumonia and other health complications.
What are the symptoms of Australian flu?
The symptoms of most flu, including H3N2, are similar, but different strains can be more severe or contagious than others.
The NHS says flu symptoms come on very quickly and can include:
a sudden fever – a temperature of 38C or above
aching body
feeling tired or exhausted
dry, chesty cough
sore throat
headache
difficulty sleeping
loss of appetite
diarrhoea or tummy pain
nausea and being sick
The symptoms are similar for children, but they can also get pain in their ear and appear less active.
How to treat flu yourself if you have flu
To help you get better more quickly, the NHS advises you to:
rest and sleep
keep warm
take paracetamol or ibuprofen to lower your temperature and treat aches and pains
drink plenty of water to avoid dehydration (your pee should be light yellow or clear)
When should you see your doctor if you have flu?
You should see a GP if:
your symptoms don't improve after seven days
you're worried about your child's symptoms
you're 65 or over
you're pregnant
you have a long-term medical condition – for example, diabetes or a heart, lung, kidney or neurological disease
you have a weakened immune system – for example, because of chemotherapy or HIV
source : http://www.walesonline.co.uk/news/health/australian-flu-symptoms-what-look-14101923