London: A new vaccine which gives lifelong protection against all flu strains could be available within five years, scientists say. Researchers have found positive results in the first human trials of a new vaccine candidate that works even if the virus mutates. Scientists in Britain and Europe are poised to recruit thousands of people for large-scale trials which they hope will lead to widespread availability of the injection by 2018. "This vaccine has the potential to save thousands of lives a year. Everyone working on it is wildly enthusiastic about the first positive results from small human trials," said Professor John Oxford, Britain's leading expert on flu and the study's key researcher. The study, conducted on almost 100 patients, has received a multi-million pound European Union grant, the 'Daily Express' reported.

Flu is one of the biggest global killers, causing up to 500,000 deaths every year. The threat is more when it mutates from a strain that attacks animals, particularly birds, and infects humans. Current patients are given annual vaccines to protect them against most forms of influenza. But the jabs attack proteins known as H and N on the outside or "coat" of the virus. These proteins are changeable and when they alter the vaccine is likely to become ineffective. The aim of the universal jab is to overcome this by attacking parts of the virus that do not change, researchers said.