The Health Protection Agency (HPA) said the Fujian-like strain had been responsible for the deaths of two children in England in the past month.

The Scottish Centre for Infection for Environmental Health said yesterday that three others had died from flu in the past two months, two of which had so far been confirmed as the Fujian strain.

The HPA urged people to be aware of the symptoms and for anyone over 65 or in the “at risk” groups to make sure that they are vaccinated against flu.

The Fujian-like strain which recently appeared in Australia was described as the country’s biggest outbreak for five years and put a severe strain on its health service.

Britain has become used to relatively few cases of flu in recent years. Even at its peak last year, fewer than 50 people in every 100,000 went to the doctor with flu-like symptoms, compared with the winter of 1989, when almost 600 people in every 100,000 seen had flu-like symptoms.

The HPA’s figures showed that, after an unusually quiet three years, the number of flu cases was now rising to what was considered to be normal seasonal levels in England. The agency said that it was too early to predict whether the numbers would be higher than average this year, but flu was appearing earlier than normal.

On average, three children a week die in England during the winter from respiratory infections often caused by flu.

John Watson, a respiratory expert at the HPA, said: “Laboratory testing so far this year shows that the main strain circulating is a flu A (H3N2) Fujian-like strain.

“This is slightly different to the A (H3N2) Panama-like virus, which has been circulating in the UK in recent years.

“The flu vaccine contains the Panama-like virus and is considered to offer some protection against the Fujian-like strain and good protection against other strains that may also circulate.”

He added: “Children and adolescents have been particularly affected and there have unfortunately been a few deaths due to flu reported in children in England over recent months.

“HPA laboratory testing has shown that two of these cases resulted from infection with the Fujian-like strain. Over the winter we usually see around three deaths in children from respiratory illness in England each week.”

Professor John Oxford, a flu expert, said: “There has been a problem in the southern hemisphere during their winter with a rise in the number of cases of influenza A, which causes more problems than influenza B. Of these, about half have been the H3N2 designation, the most worrying form.”

Sir Liam Donaldson, the Chief Medical Officer, has written to doctors to make them aware of the situation and remind them of the guidance on vaccinations and treatment.

He said: “Surveillance suggests that we are moving into the flu season. After three relatively quiet years, influenza A is appearing somewhat earlier than normal seasonal patterns.

“Overall figures released by the Royal College of General Practitioners today for week 44 show GP consultation rates for influenza-like illness remain relatively low.

“However, rates are increasing, particularly among children in the North and central parts of the country.”

THE SYMPTOMS

• Headache
• Fever of 38.9-40C for three to four days
• Cough, initially dry
• Sore throat, more noticeable after Day 2
• Aching muscles and joints, can be severe
• Stuffy nose, sneezing: more noticeable after Day 2
• Chills
• Tiredness can last two to three weeks
• Symptoms worse than ordinary cold
• Severity ranges from minor symptoms to pneumonia
• Children may also feel sick (nausea) or have vomiting or diarrhoea

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