This SARS outbreak has a potentially huge and adverse impact on global stability. It is widely-quoted that the Chinese economy must grow something like 7-10% annually just to keep up with population growth. One of the reasons that the US has consistently kept free trade relations with China (besides cold cash) was to prevent the unemployment and upheaval that would certainly result if China were cut out of US markets. If China were to experience massive internal disruption, some experts have theorized that the government would drum up nationalism and could attack Taiwan.
Despite SARS relatively low mortality rate, it has the potential to severely disrupt China's economy particularly in the crucial Pearl River Delta region.
Right now it just seems like a nasty disease but history takes some strange turns sometimes.