A grandmother-of-three thought she was safe from swine flu after she had the vaccine months ago.
But Eleanor Carruthers, 68, from Merseyside became the latest victim of the outbreak on Saturday.
Mrs Carruthers was seriously ill with emphysema and lung cancer, but had had the flu vaccination in October to protect her from the illness.
Despite the step, she was rushed to the Royal Liverpool Hospital last week and later died. H1N1 (swine flu) was recorded as one of the main causes of her death.
She leaves behind three children and her husband Alf, 69. Today her daughter, Carole, 46, said they were all shocked by how quickly her condition deteriorated.
She said: ‘What we don’t understand is that mum had the vaccine in October, because she was in an at risk group.
‘And even though she was ill, she had been OK until her breathing worsened very quickly on Saturday morning.
‘It was such a sudden thing, she died that night.
‘I had been ill at New Year, and asked the doctors whether I should keep away from mum, but they said the vaccine would protect her from flu.’
She added: ‘I feel totally lost without her, both my brothers Alan and John do not know what to do.
‘My dad is so lost as well, he had known my mum since he was seven and they had been married for 47 years.
‘She was a happy loving woman, she would give you anything and go without herself. She was still so full of life and the family will not be whole without her at the centre.’
The NHS says the seasonal flu vaccine gives 70 to 80 per cent protection from flu.
A spokeswoman for Liverpool PCT said: ‘Although we can’t comment on individual cases, this is obviously a very sad time for the family of the person concerned and our hearts go out to them.
‘Expert advice from the World Health Organisation, the Joint Committee on Vaccination and Immunisation and the Department of Health is that the flu vaccine is a highly effective vaccination and the best way for people in ‘at risk’ groups to protect themselves from the virus.’
It comes as latest official figures reveal flu has now claimed 112 lives since October – more than double the number reported last week.
Out of these, 95 had the swine flu strain and the majority of those who died were under 65 years old
The Health Protection Agency said although flu deaths had more than doubled from 50 cases last week, most of these deaths occurred in December.
‘Due to the backlog over the seasonal holiday period they have only been confirmed this week,’ a spokesman said.
Professor John Watson, head of the respiratory diseases department at the HPA, said: ‘Our latest flu report suggests levels of people seeing their doctor for flu-like illness is beginning to plateau but this may be skewed by the recent holiday period.’
The number of people in critical care in England has fallen from 783 last week to 661.
The majority of deaths hit adults of working age with 70 deaths among the 15-64 years olds. There were nine cases among five to 14 year olds and six deaths in children under the age of five.
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