"We just don't know how it is going to pan out," said John Ip, a senior economist with Morley Fund Management in London. With the Flu making an entry into western industrialized countries, financial markets, are pretty clueless to its repercussions, clearly fueled by common factors like interest rates, oil price etc.
This is probably because bird flu has not wrecked large-scale havoc yet; in terms of the human deaths, 92 being the global human death count of bird flu. Therefore the economic impact has been more localized.
Another reason for the market's indifference is perhaps because bird flu has limited itself to bird to human infections rather than the dangerous human-to human type. Thankfully, it has not reached alarming pandemic proportions, to cause any upheaval to the economy.