The Centers for Disease Control and Prevention has temporarily paused laboratory testing for several infectious diseases, including rabies and pox viruses such as mpox, as part of an internal review of its diagnostic services. The decision affects a range of specialized tests typically conducted to support state and local public health laboratories across the United States.
The agency plays a critical role in performing advanced diagnostic testing for pathogens that require high-level biosafety infrastructure and technical expertise. While many routine tests are widely available through commercial laboratories, certain rare or high-risk infections depend on centralized testing capacity at the CDC. The current pause therefore represents a significant shift in how these services are delivered.
Major tests paused across multiple categories, include fungal identification, parasitic diseases (such as cysticercosis and schistosomiasis), viral infections (including rabies, poxvirus, adenovirus, and herpesviruses), and select respiratory and serology panels are currently temporarily paused, with some requiring CDC consultation or alternative testing pathways.
While several of these tests have commercial or state laboratory alternatives, many specialized diagnostics, particularly for rare pathogens like rabies, poxviruses, and certain parasites remain dependent on CDC expertise, limiting immediate replacement options.
With the pause in place, a portion of the testing burden is expected to shift toward state public health laboratories and commercial diagnostic providers. Laboratories in states such as New York and California already have the capability to conduct certain rabies tests and preliminary analyses for pox viruses.
However, these institutions typically rely on the CDC for confirmatory testing and for integrating results into nationwide surveillance systems.
This distinction is particularly important because the CDC not only performs laboratory diagnostics but also compiles and interprets data at a national level.
A major factor contributing to the pause is a reduction in workforce capacity within the CDC. The agency has experienced significant staffing challenges due to layoffs, hiring freezes, and the non-renewal of specialized contracts. According to reporting by The New York Times, the teams responsible for rabies and pox virus testing have been particularly affected, with substantial losses in experienced personnel, only 1 remaining in the rabies team and none in the others, effective from July.
These reductions have limited the CDC’s ability to sustain specialized testing operations and provide continuous expert consultation to state and local health authorities.
See also: CDC Sidelines Six Childhood Vaccines Despite Millions of Lives Saved
Beyond workforce constraints, the CDC has been conducting an agency-wide evaluation of its laboratory services since late 2024. This review aims to assess the efficiency, relevance, and sustainability of its diagnostic portfolio. Some tests are being reconsidered because they overlap with services available in commercial or academic laboratories, while others require resources that are currently limited.
As reported by New York Times, Andrew Nixon, spokesman for the Department of Health and Human Services(HHS), said in an emailed statement, “We anticipate some of these tests will be available through C.D.C. labs again in the coming weeks.” “In the meantime,” he added, “C.D.C. stands ready to support our state and local partners to access the public health testing they need.
See also: Two Deaths Confirmed by CDC After Rabies-Infected Kidney Transplant
The pause has raised questions about the broader implications for public health preparedness. Rabies, although rare in humans in the United States, only 5 cases reported every year, remains a critical concern due to its extremely high fatality rate if untreated.
Similarly, pox viruses, including mpox, continue to require careful surveillance following recent outbreaks. The CDC’s role in confirming cases and tracking disease patterns nationally is central to managing such threats effectively.
Experts cited by The New York Times have expressed concern that limitations in testing capacity and expertise could affect the country’s ability to respond rapidly to emerging infectious diseases, particularly in scenarios involving large public gatherings or unexpected outbreaks.
Federal health officials have indicated that the testing pause is intended to be temporary. The U.S. Department of Health and Human Services has stated that some services may resume in the coming weeks as the agency continues its evaluation and addresses operational challenges.
Reference
Centers for Disease Control and Prevention. “Test Directory.” Infectious Diseases Laboratories. Last modified January 26, 2026. Accessed April 2, 2026 https://www.cdc.gov/infectious-diseases-labs/php/test-directory/index.html
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