Researchers in China have reported the first identified outbreak caused by a local Campylobacter jejuni infection in Beijing.

A total of 14 patients were sick who worked at the same factory. They had shared a common meal supplied from a meal delivery company. The outbreak was not related to the ongoing COVID-19 outbreak.

“Recently, the accelerated pace of life may dramatically increase use of meal delivery in major cities and may subsequently increase the risk of infection or food poisoning caused by foodborne pathogens,” said researchers in an article in China CDC Weekly.

In late August 2019, the Shunyi District Center for Disease Control and Prevention (CDC) of Beijing was informed that several acute gastroenteritis patients visited the Shunyi District Hospital and Shunyi Chinese Medicine Hospital. The epidemiological investigation was led by Shunyi CDC.

Time of illness onset of the first and final patient were the afternoon of Aug. 24 which was 26 hours after the meal and morning of Aug. 26 which was 66 hours after the shared meal. The report did not mention what foods were involved.

Patients showed similar clinical symptoms, including high fever, diarrhea, abdominal pain, and headache. All of them had watery stool and diarrhea two to 10 times per day. According to the investigation, they worked at the same factory and the diarrhea happened after a lunch supplied from a meal delivery company on Aug. 23.

Positive food workers
Fourteen samples from patients were positive for Campylobacter jejuni, including 12 from 12 patients and two from two food workers. A total of 18 suspected food samples and six samples from the environment of the kitchen were also collected but they were negative.

Antibiotic susceptibility testing for 11 antimicrobials was performed. All 14 seleced isolates were resistant to nalidixic acid and ciprofloxacin and sensitive to nine other medicines.

Isolates from two food workers were of the same genotype as the other patients. According to their health history, they did not have significant clinical symptoms but they could have contaminated the food during preparation.

“We do not know if they ate the same food as the patients on Aug. 23 or if the bacteria they carried contaminated the foods they cooked,” said researchers.

A pilot surveillance study revealed Campylobacter was the most common pathogen in diarrheal cases in Beijing.

Surveillance and risk assessment for Campylobacter infection particularly Guillain-Barré Syndrome (GBS) associated Campylobacter jejuni infection in China should be closely monitored, said researchers.

One gastroenteritis outbreak caused by Campylobacter coli infection was identified last year and involved three people.