CDC Temporarily Halts 31 Infectious Disease Tests Amid Quality Review and Staffing Crisis

The Centers for Disease Control and Prevention (CDC) has temporarily suspended laboratory testing for 31 infectious diseases and parasites, including high-profile conditions such as rabies, chickenpox, and Epstein-Barr virus (EBV), as part of a sweeping quality assurance review initiated in late 2024. The decision, announced this week, reflects a deliberate pause in routine operations to scrutinize assay accuracy, reliability, and procedural compliance across the agency’s vast network of public health laboratories. While the CDC has emphasized that the interruption is temporary and part of standard protocol, the timing has raised concerns among state and local health officials already grappling with a cascade of crises—including leadership vacuums, mass layoffs, and severe staffing shortages—that have eroded the agency’s operational capacity. Public health experts warn that prolonged delays in diagnostic testing could impede disease surveillance, outbreak response, and patient care, particularly during a period marked by rising measles cases and renewed scrutiny of the U.S. public health infrastructure.

Why Did the CDC Pause Testing for 31 Infectious Diseases?

The CDC’s decision to halt testing for 31 diseases stems from a formal review launched in October 2024, when the agency established the Office of Laboratory Systems and Response (OLSR). This new division was tasked with modernizing and streamlining the CDC’s laboratory operations, which had been criticized for inefficiencies, outdated technology, and inconsistent quality control across its 100-plus domestic and international laboratories. The OLSR’s mandate includes conducting routine evaluations of diagnostic assays—laboratory tests designed to detect pathogens such as viruses, bacteria, and parasites—to ensure they meet federal standards for sensitivity, specificity, and reproducibility. According to internal documents reviewed by *The New York Times*, the current review is part of a broader effort to align the CDC’s testing protocols with the Clinical Laboratory Improvement Amendments (CLIA), a federal regulatory framework that governs laboratory testing in the United States. While the agency did not disclose specific failures, experts familiar with the process note that such pauses often occur when assays are found to produce inconsistent results, cross-react with other pathogens, or fail to meet updated performance benchmarks.

The Role of the Office of Laboratory Systems and Response

Created as part of a reorganization spearheaded by CDC Director Mandy Cohen, the OLSR represents a strategic pivot toward data-driven, centralized oversight of the agency’s laboratory network. Before its formation, the CDC’s laboratories operated with significant autonomy, leading to variability in testing protocols and quality assurance practices. The OLSR’s responsibilities now include standardizing assay validation, managing supply chain logistics for reagents and equipment, and coordinating with state and local health departments to ensure seamless diagnostic support. In a statement to *The Guardian*, a CDC spokesperson framed the temporary pauses as a proactive measure: *"Several infectious disease tests are temporarily paused as CDC evaluates these assays as part of our routine review to uphold our commitment to high quality laboratory testing. CDC maintains regular communication with state and local health departments and can assist in coordinating testing through alternative laboratories if needed."* The agency added that it expects many of the paused tests to be reinstated within weeks, pending resolution of the quality issues.

How Staffing Shortages Are Deepening the Crisis

The CDC’s decision to pause testing arrives at a precarious moment for the agency, which has been rocked by a series of destabilizing events over the past year. Since early 2024, the CDC has faced a deadly workplace shooting at its headquarters in Atlanta, a wave of mass layoffs affecting hundreds of employees, and a prolonged vacancy in the agency’s top leadership position following the resignation of former Director Rochelle Walensky in 2023. The leadership vacuum was partially addressed in July 2024 with the appointment of Mandy Cohen—former North Carolina Secretary of Health—as the new director, but experts say the transition has not yet stabilized operations. Compounding these challenges are severe staffing shortages, which have reached a critical point: according to sources cited by *The New York Times*, CDC staff will no longer be able to provide after-hours technical assistance to state health departments—a service that has been available for decades. This reduction in support is particularly concerning for smaller or under-resourced health departments that rely on the CDC’s expertise to interpret test results, manage outbreaks, and deploy resources during emergencies.

Impact on State and Local Health Departments

For state and local health departments, the CDC’s testing pause has created immediate operational hurdles. While the agency has pledged to assist in coordinating alternative testing through partner laboratories, many jurisdictions lack the budget or infrastructure to quickly reroute samples. In an interview with *Healthline*, Dr. Marcus Plescia, Chief Medical Officer for the Association of State and Territorial Health Officials (ASTHO), described the situation as *a significant disruption to our ability to monitor and respond to infectious disease threats. When the CDC can’t provide timely testing, it forces states to either delay diagnoses or seek out private labs, which can be costly and may not accept Medicaid or uninsured patients.* The impact is especially pronounced for diseases that require rapid confirmation to trigger public health interventions, such as measles or tuberculosis. In early 2025, for example, multiple states reported delays in confirming measles cases due to the CDC’s testing backlog, raising concerns about unchecked transmission in communities with low vaccination rates. Public health officials also warn that the pauses could undermine the CDC’s ability to track emerging pathogens, including new variants of influenza or respiratory syncytial virus (RSV), which rely on consistent surveillance data.

The Measles Resurgence and Testing Gaps

The timing of the CDC’s testing pause is particularly alarming in the context of a resurgent measles outbreak. According to the CDC’s most recent data, there were 45 confirmed measles cases in the United States during the first three months of 2025—a 300% increase compared to the same period in 2024. The rise has been attributed to declining vaccination rates, international travel, and gaps in herd immunity. In late March 2025, officials in Cook County, Illinois, issued a public health alert warning of possible measles exposure at O’Hare International Airport, where a contagious traveler passed through Terminal 5 during a four-hour window. While the CDC played a critical role in tracking the exposure, the agency’s reduced testing capacity could hinder its ability to rapidly identify and contain similar incidents in the future. Dr. Peter Hotez, a vaccine scientist and dean of the National School of Tropical Medicine at Baylor College of Medicine, emphasized the stakes in a recent op-ed: *"When public health laboratories are weakened, the consequences are measured in preventable illnesses and deaths. Measles is one of the most contagious viruses on Earth, and every missed case is an opportunity for an outbreak to spiral out of control."

What Diseases Are Affected by the CDC’s Testing Pause?

The CDC has not released a full list of the 31 diseases impacted by the testing pause, but internal communications and statements to media outlets have confirmed the inclusion of several high-priority pathogens. Among the conditions listed are: - **Rabies**: A fatal viral disease transmitted through animal bites, requiring rapid diagnosis to initiate post-exposure prophylaxis (PEP). - **Chickenpox (Varicella)**: While vaccination has reduced cases, outbreaks still occur, particularly in unvaccinated populations. - **Epstein-Barr Virus (EBV)**: The primary cause of infectious mononucleosis, EBV is also linked to certain cancers and autoimmune diseases. - **Dengue Fever**: A mosquito-borne illness with increasing incidence in the U.S., particularly in Florida and Texas. - **Histoplasmosis**: A fungal infection that can cause severe respiratory illness, especially in immunocompromised individuals. - **Leptospirosis**: A bacterial disease spread through contaminated water, increasingly detected in flood-prone areas. Public health experts note that some of these diseases—such as rabies and dengue—require immediate laboratory confirmation to guide treatment decisions. Others, like EBV, may be less urgent but still critical for surveillance purposes. The CDC has assured that alternative testing options are available through the Association of Public Health Laboratories (APHL) and the FDA’s network of regional laboratories, but the logistics of rerouting samples can add days or weeks to turnaround times.

The Broader Implications for U.S. Public Health

The CDC’s current operational challenges reflect deeper systemic issues within the U.S. public health infrastructure. Since the COVID-19 pandemic, the agency has faced relentless criticism for its slow response to early outbreaks, inconsistent messaging, and perceived lack of transparency. The pandemic also exposed long-standing weaknesses in the nation’s laboratory network, including shortages of reagents, outdated equipment, and a shortage of trained microbiologists. While the CDC has taken steps to address these issues—such as investing in the Advanced Molecular Detection (AMD) program and expanding its BioHub network—the agency’s ability to fulfill its core mission has been repeatedly tested. The testing pauses, staffing shortages, and leadership turnover are symptoms of a larger problem: a public health system that is underfunded, overburdened, and struggling to adapt to 21st-century health threats. As Dr. Georges Benjamin, Executive Director of the American Public Health Association, noted in a recent interview: *"The CDC is the backbone of our public health response, but it can’t function effectively if it’s constantly in crisis mode. We need sustained investment in our laboratory infrastructure, a stable workforce, and clear leadership to prevent the next outbreak from becoming a catastrophe."

Key Takeaways: What You Need to Know

• The CDC has temporarily paused testing for 31 infectious diseases, including rabies and Epstein-Barr virus, as part of a quality assurance review initiated in late 2024 to standardize laboratory protocols.
• The decision coincides with severe staffing shortages, mass layoffs, and leadership instability at the agency, which has reduced its ability to provide after-hours support to state health departments.
• State and local health officials warn that the pauses could delay diagnoses, hamper outbreak response efforts, and undermine disease surveillance—particularly for measles and other highly contagious illnesses.
• The CDC has pledged to assist in rerouting samples to alternative laboratories and expects many paused tests to resume within weeks, but the interim disruptions raise concerns about public health preparedness.
• Public health experts emphasize that the CDC’s challenges reflect broader systemic weaknesses in the U.S. public health infrastructure, which has struggled to recover from the strains of the COVID-19 pandemic.

How Are State Health Departments Responding?

In response to the CDC’s testing pauses, state health departments have adopted a mix of strategies to mitigate the impact on their operations. Larger states with robust laboratory networks, such as California and New York, have redirected samples to in-house facilities or contracted with private laboratories to ensure continuity of testing. For example, the California Department of Public Health has temporarily shifted rabies testing to its own Viral and Rickettsial Disease Laboratory, while the New York State Department of Health has leaned on its Wadsworth Center—a state-of-the-art facility that has handled high-volume testing during past outbreaks. Smaller or rural states, however, lack the resources to quickly scale up alternative testing and are increasingly reliant on the CDC’s support. In interviews with *Stat*, officials from the Utah Department of Health noted that their laboratory staff were working overtime to process samples, but acknowledged that delays were inevitable without federal assistance. Meanwhile, the Association of Public Health Laboratories (APHL) has launched an emergency coordination effort to connect states with accredited labs that can perform the paused tests, though the process is not without challenges. *"We’re seeing states that have never had to outsource testing before now doing so for the first time,"* said APHL CEO Dr. Michael Pentella. *"It’s a logistical nightmare, and it’s taking time away from their core public health work."

What’s Next for the CDC and Public Health?

The CDC has framed the current testing pauses as a temporary but necessary step to ensure long-term quality and reliability in its laboratory operations. In its statement to *The Guardian*, the agency reiterated its commitment to reinstating the paused tests as soon as possible, noting that *"anticipate some of these tests will be available through CDC labs again in the coming weeks."* However, public health advocates are calling for more systemic changes to prevent future disruptions. Key priorities include: - **Sustained Funding**: The CDC’s budget has fluctuated in recent years, with Congress often delaying appropriations or imposing across-the-board cuts. Advocacy groups are pushing for a dedicated fund for laboratory modernization and workforce development. - **Workforce Stabilization**: The mass layoffs and after-hours support reductions have left the CDC understaffed at a time when demand for its services is rising. Experts recommend targeted hiring initiatives and competitive salaries to retain skilled personnel. - **Technology Upgrades**: Many of the CDC’s laboratories still rely on outdated equipment and manual processes. Investments in automation, genomic sequencing, and digital reporting systems could improve efficiency and accuracy. - **Transparency and Communication**: The CDC has faced criticism for its lack of clarity during crises. Improved public communication about testing pauses, expected timelines, and alternative resources could help states and the public prepare for disruptions. Looking ahead, the agency’s ability to rebuild trust and operational capacity will be critical not only for addressing the current testing gaps but also for preparing for future pandemics, antimicrobial resistance, and emerging infectious threats. As Dr. Anthony Fauci, former director of the National Institute of Allergy and Infectious Diseases, recently remarked: *"The CDC is at a crossroads. It can either double down on the reforms it’s begun or risk further erosion of its ability to protect Americans. The stakes couldn’t be higher."

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