* H1N1 virus has spread more quickly than other pandemics

* WHO says pointless to count individual cases

* But countries should track deaths, unusual patterns

By Stephanie Nebehay

GENEVA (Reuters) - The World Health Organization (WHO) said on Thursday that the H1N1 flu pandemic was the fastest-moving pandemic ever and that it was now pointless to count every case. The United Nations agency, which declared an influenza pandemic on June 11, revised its requirements so that national health authorities need only report clusters of severe cases or deaths caused by the new virus or unusual clinical patterns.