USA Faces Threat from 'Potentially Dangerous' Fungus
Fungal contamination suspected in multiple agroterrorism incidents within the U.S., as per research findings.
A fungus branded as a possible agroterrorism tool by the Trump authorities, allegedly orchestrated in a recent arrest, appears to stem from North America and is already common across the country, suggests a scientist affiliated with the federal government.
Researcher Yunqing Jian, along with her boyfriend Zunyong Liu, were charged with attempting to sneak strains of the fungus named Fusarium graminearum into the United States. Jian was employed at the University of Michigan, according to authorities, and Liu works at a Chinese university. The duo has collaborated on research regarding the fungus.
"The FBI seized a Chinese citizen within the U.S. on allegations of transporting a lethal biological pathogen into the country," declared FBI Director Kash Patel on Tuesday through a post on X.
According to records of the case, Liu reportedly told customs officials his purpose was to continue his research with the strains at the University of Michigan lab where Jian was employed, bypassing protocols that require documentation and safeguards to securely transport fungi for research studies.
F. graminearum prevails extensively in US native grasses and crops, per scientists. It spreads and thrives predominantly during wet conditions, causing the common crop sickness, Fusarium head blight or head scab, as per the U.S. Department of Agriculture’s Agricultural Research Service.
"It's widespread in North America. It probably rose in North America, so it's not some foreign invader. And it's already creating problems in US agriculture," Harold Kistler, an adjunct professor at the University of Minnesota, shared with our News.
Kistler explained that scientists believe F. graminearum likely evolved in North America since its closest relatives are found on the continent.
"Graminearum itself is dispersed worldwide, and likely due to the distribution of grain from North America worldwide,” he stated.
Kistler used to serve as a researcher for the USDA’s Agricultural Research Service, studying fungi like F. graminearum and the disease it brings about. During his tenure, he collaborated on research with Liu and Jian, discovering new molecular indicators of the disease's potential mitigation.
"It's a significant concern. The issue is because there's no naturally occurring resistance to the disease. And people have been trying for a long time to locate resistance. It's just a tough obstacle to overcome," Kistler asserted, discussing the head blight caused by F. graminearum.
U.S. farmers depend on various methods to minimize the risk of F. graminearum, which includes using fungicides. However, scientists have been concerned about the possibility of mutations that could render fungicides less effective.
"The fungicides are expensive. Thus, it's an extra cost to farmers. But it's justified because, without it, their crops could be utterly lost—not only due to yield reduction, but because what grain they might have would be polluted with these toxins,” Kistler explained.
Over $10 billion was lost to epidemics caused by the fungus in the 1990s, according to estimates by researchers and agriculture officials. The U.S. Food and Drug Administration constantly monitors for the toxins that are generated by fungi like F. graminearum, including deoxynivalenol, also known as vomitoxin or DON, which can lead to vomiting and diarrhea in humans consuming excessive amounts of it.
“It is impossible to entirely eliminate the presence of DON in wheat. DON can be found in wheat grown under normal weather conditions; however, the fungus flourishes in cool, wet conditions,” the FDA stated in a 2010 alert to states and grain groups.
U.S. distributors also test grain for the presence of these toxins to maintain the food supply safe.
"If it's excessive, they will reject it. They won't procure it. Or they will reduce the amount they'll pay for it. If it's barely beyond the limit, they can mix it with grain that doesn't have the toxin to maintain below the safety limit,” he stated.
Alexander TinAlexander Tin is a digital journalist for our News based in the Washington, D.C. bureau. He covers federal public health agencies.
Background:
Fusarium Graminearum: A Global Threat
Fusarium graminearum, a globally dispersed plant pathogen, is renowned for causing Fusarium head blight in wheat and other minor grains. It also affects barley and corn, leading to significant production and quality losses[1][4]. This fungus is famous for producing toxins like vomitoxin (also known as deoxynivalenol), which can cause adverse health effects in animals and humans[2][3].
Origin of Fusarium Graminearum
Researchers surmise that Fusarium graminearum likely originated in North America, as its closest relatives are discovered on this continent. Its global distribution is primarily due to the trade of grains from North America[5].
Impact on US Agriculture
Fusarium head blight is regarded as the most economically significant wheat disease in North America, significantly decreasing both yield and grain quality[1]. The disease is prominent in the eastern and Upper Midwestern United States, where weather conditions—particularly excess moisture—favor its spread[3].
Mitigation Strategies
Several strategies are employed to mitigate the influence of Fusarium graminearum:
- Breeding Resistant Varieties: Plant breeders have been working on developing wheat and corn varieties that are more resistant to the fungus, reducing the need for fungicides[3].
- Fungicides: Chemical treatments are used to inhibit or reduce the severity of fungal infections[1].
- Crop Management and Testing: Grain producers use stringent testing protocols at grain elevators to ensure mycotoxin levels remain within safe thresholds[1].
Agencies and Regulations
The U.S. agricultural industry, supported by agencies such as the USDA, has strict regulations for handling and moving pathogens, including fungi. Researchers must secure permits through the USDA Animal and Plant Health Inspection Service (APHIS) for any transportation of foreign plant or fungal strains across national or state borders[1][2].
Recent accusations against two Chinese researchers of smuggling Fusarium graminearum into the U.S. without proper permits have brought concerns about the possible introduction of more aggressive or genetically distinct strains into the environment[2][3]. Nonetheless, the fungus is already prevalent in the U.S., and ongoing research focuses on understanding its genetic variations and developing effective disease management strategies[2][5].
- The FBI has charged a couple, Yunqing Jian and Zunyong Liu, with attempting to smuggle strains of the Fusarium graminearum fungus into the United States, alleged to have originated from North America and already common across the country.
- Scientists like Harold Kistler, say that Fusarium graminearum likely evolved in North America as its closest relatives are found on the continent, making it not a foreign invader.
- The U.S. Department of Agriculture is aware of the extensive prevalence of F. graminearum in US native grasses and crops, as the fungus thrives mainly in wet conditions, causing Fusarium head blight or head scab.
- The food and agricultural industry faces challenges in mitigating the effects of Fusarium graminearum, with the U.S. Food and Drug Administration constantly monitoring for toxins generated by the fungus, such as deoxynivalenol, which can lead to health issues like vomiting and diarrhea in humans consuming excessive amounts of it.
