Taiwan has long desired to join the WHO. Politics, specifically the objections of the Chinese Government, continue to prevent Taiwan from joining. Here is an excerpt from a fairly typical recent editorial on this subject from the Taipei Times.
How could a supposedly lofty organization such as the WHO continue to allow outdated political considerations to override the right of millions of people in this country to proper health care — especially since such a move places the health of billions more around the world at risk?