April 27 data show that U.S. COVID-19 death rates are at least eight times higher than in countries with early and prophylactic use of HCQ.

Prophylactic use means use for the purpose of prevention.

Source:

• 
  April 29, 2020. “Where’s the Evidence on COVID-19 Treatment?” AAPS | Association of American Physicians and Surgeons.
  https://aapsonline.org/evidence-hydroxychloroquine/.
  Doctor Organization.