It is the doomsday scenario that many futurologists believe is the biggest threat to human life – a deadly flu pandemic from a virus resistant to all the drugs science can produce.
Such an apocalyptic vision has led to the end of civilisation in many a Hollywood blockbuster, but a team of scientists in the West are trying to stop that happening in the first place.
Now the team from the University of Bath believes it has taken a giant step in the key challenge facing the human race – how to develop drugs against which a flu virus cannot develop resistance.
The researchers from Bath, the University of British Columbia in Canada and also in Australia are about to start pre-clinical trials on humans for a new kind of drug that could stop the flu virus – any kind of flu virus – in its tracks.
The new drugs have been successfully tested on animals and are different in the way they tackle the flu bug. Whereas traditional antiviral flu drugs such as Tamiflu and Relenza bind competitively to the neuraminidase enzymes in the body, the enzymes that help the virus spread through the body, the new drugs from Bath University bind permanently to the flu protein itself and block its action.
Dr Andrew Watts, a lecturer in pharmacology at Bath, said the big fear across the world was a deadly strain of flu developing that was resistant to current drugs.
"Antivirals have been very effective in stopping the spread of flu in the pandemics over the past few years; however, new strains of the virus that are resistant to these drugs are emerging and represent a serious threat to our ability to effectively treat the disease," he said.
"It is therefore vital that we develop new drugs that combat resistance. This new class of drug is based on the natural mechanism of the enzyme and so the virus can't easily evolve to avoid its action."
He said that the World Health Organisation estimates that five million people catch flu each year around the world – and as many as one in 10, some half a million, die from the bug. In pandemic years, such as 1918 or 2009, it can rise into the millions.
"While existing drugs are effective, there are fears that their over-use may cause the virus to develop resistance against them, rendering them useless," said Professor Doreen Cantrell, the chairman of the Immunity and Infections Board at the Medical Research Council, which partly funded the work.
"This study in mice opens up the possibility of new types of drugs that could stop emerging flu viruses in their tracks," she said.
"If these results are replicated in clinical trials and are shown to halt infection in flu patients, we will have turned a corner in the search for new antivirals that tackle the problem of resistance. The MRC has a long-standing commitment to flu research, building on our landmark discovery in 1933 identifying the flu virus," she added.
