CDC denial and the alliance's request

In May, California and Washington asked the CDC to validate a new measles testing method. Two months later the agency denied the request, citing "other competing priorities", according to a letter from the West Coast Health Alliance addressed to CDC director Erica Schwartz.

The letter carries the signatures of health officials in California, Hawaii, Oregon, and Washington. It asks Schwartz to reconsider and approve validation of a rapid, high-volume measles test ahead of major outbreaks, and separately asks the CDC to create protocols to test for other high-priority pathogens to prepare for future outbreaks.

What the letter says is at stake

The alliance warns that without high-throughput capacity, a large regional outbreak would make it harder to scale up diagnostic testing, impairing patient care and public health investigation. Today there is no high-throughput measles diagnostic test that the CDC has published or validated, so laboratories have to rely on lower-volume tests for measles, like individual polymerase chain reaction (PCR) tests.

Officials argue a high-volume test would dramatically strengthen laboratories' ability to respond quickly to outbreaks, aiding preparedness for pathogens like Ebola or hantavirus as well as emerging threats.

HHS response

Emily Hilliard, a spokesperson for the US Department of Health and Human Services, said the CDC is "prioritizing emerging technologies" and "ensuring state and local health departments have the support needed to strengthen measles detection and outbreak response". She did not answer questions about whether the CDC had plans to validate a high-throughput measles assay.

Existing equipment and prior work

The alliance points to capacity most public health labs already own, and to earlier test development that has not been shared:

• •During the Covid pandemic, most public health labs bought high-volume equipment such as the Hologic Panther Fusion, a PCR platform that can process up to 500 tests in eight hours.
• •Texas state laboratories developed a high-throughput measles test during the West Texas measles outbreak last year but have not distributed or published the protocol.
• •The CDC has reportedly completed studies on the Texas test and another from ARUP Laboratories, but per the officials these were not full validations or a comprehensive comparison.

The letter asks Schwartz to develop an assay, or test, for measles diagnostic testing on the Panther Fusion and to publish that protocol so any lab can run it. The CDC has so far denied the request.