C.D.C. Ignored Request From States to Validate a New Measles Test The agency replied two months later, saying it had “competing priorities,” officials from a coalition of Western states said.

Health officials in California and Washington, facing outbreaks of measles this past spring, asked the Centers for Disease Control and Prevention in May to validate a test that can diagnose 500 cases in eight hours.

They did not hear back for two months. Officials from the West Coast Health Alliance — California, Washington, Oregon and Hawaii — recounted the experience this week in a letter to Dr. Erica Schwartz, the C.D.C.’s new director, who assumed the position in August, shortly after they got the agency’s reply. According to the letter, obtained by The New York Times, the C.D.C. had told them that it had “other competing priorities” and could not dedicate time to making a high-volume test available to state labs.

The officials urged the C.D.C. to develop and distribute the protocols for such tests for measles and other dangerous pathogens, saying they would enable public health labs across the country to be ready for large outbreaks.

“The availability and speed of diagnostic testing can dramatically mitigate the early stages of an outbreak of infectious disease,” they wrote.

The Department of Health and Human Services, which oversees the C.D.C., did not address questions about the agency’s plans for a high-throughput test for measles that can rapidly diagnose large numbers of cases.

Emily Hilliard, a spokeswoman for the department, said in an emailed statement that the “C.D.C. is ensuring state and local health departments have the support needed to strengthen measles detection and outbreak response. Under Dr. Schwartz’s leadership, the agency is prioritizing emerging technologies to best assist our partners in responding more quickly and effectively.”Until recently, measles cases were generally rare in the United States and the disease was considered eliminated in the year 2000. As a result, commercial rapid tests for measles — which could provide a quick answer in a doctor’s office or an emergency room — are not currently available in the country.

But the disease has surged drastically in the past two years. Already this year, the C.D.C. has recorded more than 4,400 cases, and Pennsylvania has reported six deaths related to measles.

Given the swelling caseloads, medical experts believe the country needs to step up its ability to diagnose measles rapidly.

“It seems to me that it’s a fairly urgent need,” said Jill Taylor, a former director of the Wadsworth Center, New York State’s public health laboratory.

Measles is typically diagnosed after a clinic sends a sample to a public health laboratory, which relies on experienced staff to run the test. The entire process can take two business days, or up to five in states where labs are particularly short on staff.

During the coronavirus pandemic, most public health labs acquired high-throughput machines, which can significantly cut down the testing and staff time required. Now all they need is a test that has been developed and endorsed by the C.D.C.

But the C.D.C. may not currently have the capacity to evaluate and confirm the reliability of a new test, Dr. Taylor and others noted. The agency has about 30 percent fewer employees now than it did at the start of President Trump’s second term, and its work is tightly controlled by Health Secretary Robert F. Kennedy Jr. and other political appointees.

The staff are “beaten down” and “don’t have leadership at the moment to help them decide what’s important,” said Dr. Taylor, who was part of a committee convened to assess the C.D.C.’s lab operations. “I feel so bad for them, but given what’s happening, this ought to be a priority,” she added.

Last year, public health labs in Texas and Utah developed and validated their own tests to cope with measles outbreaks in their states. “All states can design and implement a laboratory-developed test, but having a C.D.C. protocol is always helpful,” said Scott Becker, the chief executive of the Association of Public Health Laboratories.

But some experts disagreed that all public health labs have the capacity to develop their own tests. “There are many public health labs that could not develop their own but are dependent on getting a kit and getting a fully verified test,” Dr. Taylor said.

The C.D.C. typically takes the lead in developing tests for new pathogens but has not traditionally validated high-throughput ones. But that clearly needs to change, two of the agency’s own officials said, speaking on condition of anonymity for fear of reprisal.

Apoorva Mandavilli reports on science and global health for The Times, with a focus on infectious diseases and pandemics and the public health agencies that try to manage them.