A doctor examines a man for a COVID-19 test inside a testing tent at St. Barnabas Hospital in New York City on March 20. Misha Friedman/Getty Images

Health officials in New York City and Los Angeles County are signaling a change in local strategy when it comes to coronavirus testing, recommending that doctors avoid testing patients except in cases where a test result would significantly change the course of treatment.

A news release from the Los Angeles Department of Public Health this week advised doctors not to test those experiencing only mild respiratory symptoms unless “a diagnostic result will change clinical management or inform public health response.”

The recommendation reflects a "shifting from a strategy of case containment to slowing disease transmission and averting excess morbidity and mortality," according to the statement.

The guidance said coronavirus testing at L.A. County public health labs will prioritized those with symptoms, health care workers, residents of long-term care facilities, paramedics and other high-risk situations. Others are encouraged to simply stay at home.

At about the same time, the New York City Department of Health directed all healthcare facilities to immediately stop testing non-hospitalized patients for Covid-19.

“At this point in the pandemic, demand for unnecessary testing is contributing to the rapidly diminishing supply of PPE and leading to a decreasing supply of swabs and viral transport media used to collect diagnostic specimens for Covid-19 testing,” a statement read. “Testing may play a more significant role after the pandemic has peaked.”

Some context: The strategy shift essentially codifies the reality health departments have been living with for weeks; a shortage of tests and protective equipment amid rising demand and case numbers.

It also puts into practice advice from many of America’s top medical experts, including CNN’s Dr. Sanjay Gupta, that a positive test result is not required to treat the symptoms.

Naturally, limiting testing in America's two largest population centers would also likely lead to widespread under-counting of total cases.