A rare and deadly outbreak of the Andes hantavirus on a recent cruise ship has exposed a significant vulnerability in the United States’ public health infrastructure: the lack of widely available, early-stage diagnostic tests for this specific virus.
While most of the country relies on the Centers for Disease Control and Prevention (CDC) for detection, the CDC’s current capabilities are limited. This gap has left states scrambling to prepare for returning passengers, with Nebraska emerging as a potential pioneer in rapid response. The University of Nebraska Medical Center (UNMC) has developed its own polymerase chain reaction (PCR) test, positioning itself as possibly the only laboratory in the nation currently equipped to diagnose the Andes virus in its earliest, most treatable stages.
The Urgency of Early Detection
The Andes virus is particularly dangerous, carrying a fatality rate of approximately 35%. Unlike common cold viruses, it attacks the small blood vessels in the lungs, causing fluid buildup that can lead to respiratory failure and death.
However, early intervention can save lives. While there are no specific antiviral drugs for hantavirus, supportive care—such as fluid management and breathing assistance—significantly improves survival odds if administered before the disease progresses to a critical stage.
This creates a diagnostic dilemma. The primary tool available through the CDC is a serological test, which detects antibodies produced by the immune system. The problem? Antibodies do not appear until the patient is already actively sick and their body has had time to mount a defense. By then, the window for optimal early treatment may have narrowed.
“The rationale for a test is to give an early indication that they’re positive,” says Peter Iwen, director of the Nebraska Public Health Laboratory. “These folks are going to have a very low concentration of virus in their blood system once they are early on in the stages of their disease.”
PCR testing, similar to the method used during the height of the COVID-19 pandemic, can detect tiny quantities of viral genetic material before symptoms fully manifest. This allows for immediate isolation and prompt medical support, crucial for preventing severe outcomes and controlling spread.
Why Existing Tests Didn’t Work
When UNMC was notified that 16 American passengers from the affected cruise would be transported to Nebraska’s specialized biocontainment unit, Iwen immediately contacted the CDC. He learned that while the CDC possesses a PCR test for the Andes virus, it is classified as a “research test.”
Research tests are used for scientific experiments and have not undergone the rigorous validation required for clinical patient management. Using an unvalidated test for diagnosis can lead to inconsistent results, potentially missing cases or generating false positives. The CDC is currently working to validate its version, but that process takes time.
Meanwhile, existing commercial PCR tests in the US were useless against the Andes strain. Most US labs are equipped to detect Sin Nombre virus, the primary hantavirus strain found in native US rodents. The Andes virus, however, is genetically distinct and indigenous to South America. Standard US tests simply cannot identify it.
A Rapid Response: From Zero to Diagnostic Capacity
Faced with this gap, Iwen’s team mobilized to build and validate a PCR test from scratch over a single weekend.
- Sourcing Materials: The team reached out to Steven Bradfute, a hantavirus scientist at the University of New Mexico. His lab held the necessary genetic material of the Andes virus (non-infectious) and chemical reagents.
- Logistics: On Friday, Bradfute shipped the materials overnight to Nebraska.
- Validation: By Saturday morning, Iwen’s team began assembling the test. They spent Saturday and Sunday validating it by adding varying concentrations of Andes viral genetic material to samples of healthy human blood to ensure the test could accurately detect the virus.
- Result: The team used about a third of their initial 300-test capacity for validation. They now have the ability to conduct several hundred diagnostic tests on patient samples.
Lessons from Pandemic Past
This rapid deployment highlights a critical lesson from the early days of the COVID-19 pandemic. In early 2020, the CDC was the sole entity capable of running initial tests, and a rollout of faulty kits hampered national efforts to track the virus’s spread.
Kelly Wroblewski, senior director of infectious diseases at the Association of Public Health Laboratories, notes that state-level capacity for hantavirus testing remains limited, primarily confined to a few Southwestern states. However, she emphasizes that the scale of this event is different from COVID-19.
“We’re right now globally talking about a very different virus and a limited number of people being exposed,” Wroblewski says.
While the US does not need the massive testing infrastructure required during the peak of COVID-19, the ability of states to act independently is vital. Nebraska’s proactive stance—building capacity before patients arrived—exemplifies the resilience needed in modern public health.
Conclusion
As the 16 passengers await testing in Nebraska’s biocontainment unit, the state’s swift action underscores a broader truth: preparedness is not just about having tests, but having the agility to create them when standard tools fall short. Until the CDC validates its own clinical PCR test and more states expand their capabilities, local laboratories like Nebraska’s will remain on the front lines of diagnosing rare but deadly threats.
