Federal prosecutors have charged two Chinese nationals, Yunqing Jian and Zunyong Liu, with attempting to bring a toxic fungus into the United States. Jian was a postdoctoral researcher at a plant pathology lab at the University of Michigan, and her boyfriend, Liu, worked at a Chinese university. In July 2024, Liu was discovered at Detroit Metropolitan Airport with four plastic baggies containing plant material. Liu initially denied knowing what the plants were, but later admitted that he had brought samples of Fusarium graminearum to conduct experiments in Jian’s laboratory. U.S. authorities charged the pair with conspiracy, smuggling goods, making false statements, and visa fraud. Jian was arrested in Michigan, but Liu was deported back to China during the 2024 incident and is therefore out of U.S. jurisdiction.
Fusarium graminearum is a pathogenic fungus that causes Fusarium head blight disease in wheat, barley, corn, and other grains. Crops infected with this disease can pose a serious threat to humans and livestock due to the mycotoxins that Fusarium head blight produces. Infected crops, if ingested, can cause vomiting, diarrhea, and liver damage. According to the U.S. Department of Agriculture, the fungus is responsible for $1 billion of damage to wheat and barley crops each year. Prosecutors said that releasing such an infectious strain could destroy crops and have a large effect on food sourcing. However, Fusarium graminearum is already present in the U.S. and has been studied for decades. One expert even expressed uncertainty regarding the fungus being characterized as dangerous and called it a common fungus that is only a threat if misused in large amounts.