The WHO estimates that a vaccine will be available by September

The first vaccines to tackle H1N1 swine flu should be ready for use in some parts of the world in time for next month, reported the World Health Organisation (WHO).

The first results from clinical trials are expected next month and these tests will show the expected dosage needed to provide immunity.

Regulatory approval is required before the vaccine can be released but this should be forthcoming following the clinical trials, said the WHO.

At the end of July the WHO said that the swine flu pandemic had spread to 168 countries, which have officially reported over 162,000 infections leading to over 1150 deaths.

The WHO estimates that the H1N1 pandemic could affect 2bn people.

Some strains of the flu have show resistance to the anti-viral drug Tamiflu.

Flu-vaccine makers include Sanofi-Aventis, GlaxoSmithKline, Novartis, Baxter and Solvay, according to Reuters.

Number of reported cases of swine flu by region.

Region: Cases/Deaths
Africa: 229/0
Americas: 98242/1008
Eastern Mediterranean: 1301/1
Europe: 26089/41
South-East Asia: 9858/65
Western Pacific: 26661/39
Grand Total: 162380/1154