The sick food handlers are the source of the Norovirus outbreak in Australia that sickened more than 200 people. Donuts were a novel source of foodborne illness in Australia, according to a study published in Communicable Diseases Intelligence.

The owner of a food outlet informed the Australian Capital Territory Department of Health in November 2021 about a report of illness among 11 people following the consumption of doughnuts. They have received two reports of illnesses linked to the same bakery. It was discovered through interviews with patients that everyone had consumed donuts from the shop 24 to 48 hours before becoming ill.

215 out of the 301 individuals who were interviewed as part of the outbreak, met the case definition. 16 other people reported minor illnesses but did not meet the criteria. The incubation period for illnesses ranged from 9 to 112 hours, with a median of 34 hours. With a range of 3 to 91 years old and 159 female respondents, the median age of the respondents was 33. A minimum of 96 hours were required for incubation in eight cases.

All of these patients had at least one other family member who had developed the illness earlier. Scientists believe they were infected by secondary transmission rather than through a dietary source.

The symptoms were stomach pain, nausea, vomiting, and diarrhea. In eight cases, blood was found in the stools, and two patients were admitted to hospitals.

A group of 140 people were part of a patient-control research study. On that particular day, 192 donuts were produced. 27 out of the 59 people who completed the questionnaire fit the case description. There was no specific flavour of filled doughnut found to be the source of infection; however, eating any type of filled doughnut was linked to becoming ill.

When the bakery was inspected in late November, it was discovered that some of the container date labels were missing, making it impossible to ascertain whether the storage durations had been followed.

Although the cause of the contamination has not been determined, it is assumed that a food handler was exposed to infected people while handling contaminated doughnuts. The severity of the sickness also shows that proper food handling and hand hygiene practices were not followed.