NEW YORK, Sept 22, 2007 (AFP) - Disappointing results for a promising anti-AIDS vaccine have dealt a major blow to international efforts to stem the spread of the devastating disease.

The announcement Friday from US pharmaceutical giant Merck that it was halting a clinical test of the HIV vaccine was greeted with dismay after high hopes had accompanied the introduction of the V520 vaccine.

NEW YORK, Sept 22, 2007 (AFP) - US pharmaceutical company Merck has halted trials of an anti-AIDS vaccine after a study found it ineffective, the company announced Friday.

The decision is seen as a setback for the cause of combating the worldwide AIDS epidemic because the vaccine known V520 was initially billed as promising.

CHICAGO, Sept 19, 2007 (AFP) - Scientists at a major disease conference Wednesday announced a skin-patch vaccine that can save the wearer from the rumblings of diarrhea when traveling to places where stomach bugs are endemic.

A clinical trial by Maryland-based vaccine maker Iomai Corporation showed that of 59 people who used the patch -- which slaps on the skin to deliver the vaccine without a needle -- only three found their guts growling with diarrhea.

PARIS, Aug 17, 2007 (AFP) - A novel vaccine against the H5N1 bird flu could mean that far more people will be protected against the deadly disease in case of a worldwide pandemic, a study released Friday showed.

In clinical trials, the new drug not only required fewer scarce antigens, it also triggered a far more effective immune response, according to the study, published in the British journal The Lancet.

LONDON, Aug 5, 2007 (AFP) - Britain could vaccinate farm animals to prevent a mass slaughter should the foot and mouth disease outbreak spread, but the government faces a tough call on the issue.

The ghastly sight of millions of cattle carcasses being torched on pyres across the countryside was the enduring image of the 2001 epidemic.

However, the option to vaccinate also comes with problems attached.

VANCOUVER, Canada, Aug 2, 2007 (AFP) - Canadian scientists said Thursday they have made the first animal-tested vaccine against a nasty amoeba that infects 10 percent of the world population and kills 100,000 people each year.

The vaccine against Entamoeba histolytica is a breakthrough, said lead scientist Kris Chadee, because currently 'there are no vaccines for any parasite ... we have the first animal tested protective vaccine.'

The research is published in the October issue of science journal Infection and Immunity, and is available online.