Santa Clara County is formally warning the area’s big health care providers to handle more local COVID-19 testing for patients or face steep fines.

Data shows the county is carrying out far more testing than large health care providers, partially explaining the massive backup at county testing sites:

• Santa Clara County sees 15% of patients in the region, but in the last six months it handled more than 20% of the testing.
• Kaiser sees 31% of patients in Santa Clara County, but provided over 12% of testing.
• The Palo Alto Medical Foundation, or Sutter Health, sees more than 16% of county patients, but provided about 2% of all COVID testing.