The World Health Organization does not control the standards for what constitutes a case in the United States. The CDC does. That standard has not changed substantively since April. The standard for case definition for COVID-19 is here: https://wwwn.cdc.gov/nndss/conditions/coronavirus-disease-2019-covid-19/case-definition/2020/08/05/
In april they changed to single target positive. No other pcr test is allowed to do so. It was never about health.