Scientists call for action after fatal Chinese outbreak

Researchers have described an outbreak involving a rare pathogen that killed nine people in China and said there is an urgent need for improved detection and prevention strategies.

Burkholderia gladioli, particularly its pathovar cocovenenans, poses a significant public health threat through the production of bongkrekic acid.

In October 2020, a foodborne outbreak occurred during a family gathering in Heilongjiang linked to homemade fermented corn. Nine patients developed acute gastroenteritis within three hours and died within 14 days. Burkholderia gladioli was isolated from contaminated corn flour.

Incidence rates of infections are relatively low but outbreaks have been reported in countries such as Indonesia, Mozambique, and China. From 1953 to 2014, 2,359 bongkrekic acid poisoning cases were reported in China, with 905 deaths. 

High contamination levels
According to a study published in the journal Infection, Genetics and Evolution, the incident involved 12 individuals from five families, nine of whom consumed a homemade sour soup — a traditional fermented corn dish during breakfast.

Three hours later, four males and five females aged 42 to 72, began experiencing symptoms such as nausea, vomiting, abdominal pain, and diarrhea. Despite receiving treatment all nine people died within 14 days.

Local health officials collected two samples of sour soup powder and one sample from a patient. Bongkrekic acid concentrations reached 330.16 mg/kg in corn flour and 3.16 mg/L in gastric fluid, levels that far exceed estimated lethal thresholds.

Epidemiological investigations initially focused on common foodborne pathogens, such as Salmonella, and chemical toxins, including aflatoxins. Although excessive aflatoxin contamination was detected, it was ruled out as the primary cause because of its prolonged latency period, which was inconsistent with the acute onset observed in the outbreak.

Despite previous bongkrekic acid poisoning incidents in China, public awareness of this toxin remains low, and many local healthcare institutions lack the necessary resources and expertise for its timely detection, said scientists.

Researchers made several recommendations including raising public awareness given the widespread consumption of fermented corn products in China and strengthening surveillance programs with routine screening of fermented food products for Burkholderia gladioli and bongkrekic acid.

Staphylococcus aureus outbreak
In a different study, researchers have described a Staphylococcus aureus outbreak at a school in Hebei Province that affected 61 people in October 2024.

A case-control study implicated ròujiámó, a breakfast item, as the suspected vehicle. Laboratory analyses identified Staphylococcus aureus in samples collected from patients, kitchen workers, food, and the food storage and preparation environment.

Ròujiámó is a Chinese specialty snack that includes a baked bun and braised meat, and the manufacturing process is prone to food contamination, according to the study published in Food Research International. The 61 cases of diarrhea and fever occurred shortly after eating in the canteen.

The canteen, which employed 23 workers, was served with a hygiene improvement notice for failure to comply with food safety management procedures. Following the incident, cleaning and disinfection of the food processing environment and shared equipment was carried out, with health screening for kitchen workers, and removal of staff infected with Staphylococcus aureus from work.

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