Bird flu vaccine ready in a year but who will get it first?

The World Health Organisation (WHO) says a vaccine against the killer H5N1 bird flu virus could be licensed for humans within a year.

The H5N1 avian influenza virus has claimed over 150 lives since it appeared in 2003 and it's rapid spread has ignited fears of a potential global human pandemic.

Drug companies have been in hot competition since then to find a cure for the deadly virus and at least a dozen manufacturers have clinical trials underway or in the pipeline.

On the final day of a WHO vaccine conference in Bangkok, Marie-Paule Kieny, head of the WHO's Initiative for Vaccine Research, said they expect within a year that vaccines against H5N1 influenza strains would be licensed for human use.

The experts met at the seventh WHO Global Vaccine Research Forum to review developments against such diseases as malaria, dengue fever, AIDS, bird flu and human papillomavirus, which can lead to cervical cancer.

However health experts say vaccines only work well when they match the circulating strain of flu and as the H5N1 strain has not evolved yet into a form that passes easily between humans, it is unclear how effective the vaccines produced will be.

Research does suggest that some vaccines might help protect people from death if a pandemic strain does emerge and until a more precise one can be produced.

Many countries have ordered or are stockpiling pre-pandemic H5N1 vaccines such as Tamiflu, which experts recommend to immunise health care workers, firefighters and other essential staff before a pandemic breaks out.

In the UK it is thought it will take 4-6 months for the first vaccine doses to emerge from factories, and up to a year to produce enough for the recommended two doses.

David Salisbury, director of immunisation at Britain's Department of Health says data on some vaccines has shown that "even if poorly matched against the pandemic strain, they may play a valuable role in minimising disease, reducing transmission and even aborting a pandemic".

According to Kieny who receives the pre-pandemic vaccination first will be a "tricky issue".

She says immunising groups on the front line to combat the pandemic would be of benefit, but as far as the general population is concerned there is the risk of immunising against a pandemic that is not there.

The WHO says several projects are underway to boost production capacity for vaccines to protect against bird flu and other viruses with pandemic potential.

To date almost all cases of bird flu in humans have been the result of close contact with diseased birds.