LIFESTYLE
04/01/2018 14:53 GMT | Updated 10/01/2018 14:15 GMT

'Japanese Flu': Symptoms, Treatment And How To Prevent It

Why you need to know about strain 'B/Yamagata'.

A strain of flu that isn’t included in this year’s main flu vaccine is spreading, according to Public Health England (PHE).

There are many different strains of the influenza virus and, each year, vaccines are designed to target those believed to be the most of risk to the population.

This year, the main vaccine is designed to protect against three strains of flu (including the Australian flu, which has already caused fatalities in Ireland) however it does not protect against a strain of the virus called influenza B/Yamagata (or ‘Japanese flu’) - which is now spreading.

In a letter to GPs, which has been seen by HuffPost UK, PHE warned about the strain, which has been detected in a number of hospitals and care homes across the south west.

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The standard (trivalent, meaning three strain) vaccine given to most people in the UK protects against the following strains of influenza: 

:: A/H1N1 – the strain of flu that caused the swine flu pandemic in 2009.

:: A/H3N2 – a strain of flu that mainly affects the elderly and people with risk factors like a long term health condition (also known as Australian flu).

:: Influenza B – a strain of flu that particularly affects children. In 2017/18 the vaccine will contain B/Brisbane/60/2008-like virus.

There is also a vaccine - called a quadrivalent influenza vaccine - which is given to people in high risk groups, such as children, elderly people, those who are pregnant or who have asthma. This vaccine protects against the three strains listed above as well as a strain called B/Phuket.

In its latest flu report, PHE said B/Yamagata viruses were ‘antigenically similar to B/Phuket’, so the quadrivalent virus can better protect against it.

That said, a spokesperson for PHE previously told HuffPost UK the typical effectiveness of the flu vaccine is in the range of 40-60% - meaning some people can still get flu, despite having the jab.

Symptoms of flu

Flu symptoms often come on quickly with sufferers experiencing a fever, a dry chesty cough, tiredness, the chills, joint pain or aching muscles. Much of the time it will make them too unwell to do anything.

Other symptoms include: diarrhoea, abdominal pain, nausea, vomiting, a sore throat, a blocked or runny nose, sneezing, loss of appetite and difficulty sleeping. 

In a letter to GPs in the south west, PHE wrote: “Surveillance for week 51 shows a large increase in laboratory reports of both Influenza A and B, but particularly B.

“As most adults will have been vaccinated in general practice using trivalent rather than quadrivalent vaccine, it is possible that cases of flu will be seen amongst individuals, both staff and patients, who have accepted this vaccination.”

An analysis by the health body found that 21 out of 25 cases of influenza B were caused by B/Yamagata. The other four cases were caused by a strain called B/Victoria (similar to B/Brisbane, which this year’s vaccine protects against).

While B/Yamagata isn’t as severe as Australian flu (A/H3N2), there are worries that an outbreak of this strain of flu could put increasing pressure on the NHS.

Doctors and nurses who have had this year’s standard flu jab can still catch this particular strain of flu, which could increase staff absences at a time when waiting rooms are filling up.

In week 51 of 2017 (Christmas week), the overall influenza-like illness GP consultation rate was 18.9 per 100,000 in England. The week before that it was less - 11.4 per 100,000 people.

PHE confirmed in its letter that “a number of hospitals and care homes across the south west have already been affected by localised outbreaks and increased demand”.

So what should you do if you’ve had this year’s jab and are worried about catching this strain?

Professor Paul Cosford, Medical Director for Public Health England, told HuffPost UK: “The vaccine remains the best defence against the virus. It is not too late to get vaccinated and we urge all who are eligible, especially those in at-risk groups that include people aged 65 years or over, pregnant women, and those with certain chronic conditions, to take up the offer of the vaccine.”

Dr Richard Pebody, Acting Head of Respiratory Diseases department at Public Health England, advises to: 

:: Practice good hand hygiene - for example washing your hands with soap and warm water before preparing and eating food.

:: For those who are suffering symptoms of flu, carry tissues and use them to catch coughs or sneezes. Bin the tissues after using them, wash your hands regularly with soap and warm water, and frequently clean surfaces like computer keyboards, telephones and other regularly used objects.

:: Avoid having unnecessary contact with other people if you or they are presenting symptoms of flu.

Advice for people with flu

People concerned about flu-like symptoms should stay at home. PHE emphasises that patients should seek advice from a local pharmacist before contacting their GP.

Patients can contact their GP, or call NHS 111, to seek further advice. People with flu should get plenty of rest, keep warm, take paracetamol or ibuprofen to lower their temperature and treat aches and pains, and drink lots of water to avoid dehydration.

For most healthy people, recovering from flu can take roughly a week. However, for those that are more vulnerable, it can be more severe and it is important to be aware of this and seek help when needed. 

Dr Steve Iley, medical director for Bupa UK, told HuffPost UK: “If you experience sudden chest pains, difficulty breathing or coughing up blood, you should call 999 to seek immediate help.”

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