A 19-year-old man has become the first person in London to die from swine flu, taking the UK death toll to four.
The death comes after the head of the World Health Organisation (WHO) warned the international spread of the disease could be "unstoppable".
Health secretary Andy Burnham this week warned the number of swine flu cases in the UK could rise to 100,000 per day by the end of August.
However, the government's chief medical officer Sir Liam Donaldson has insisted the public avoid panic-buying "counterfeit" medication on the internet.
"The whole field of counterfeit drugs is becoming a much bigger problem, not just with [anti-flu drug] Tamiflu," he told BBC Breakfast.
"So my advice is don't buy it , you don't need to. We have got the biggest stockpile in the world and even worse than that you might end up with something that is poisonous and dangerous."
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