BACKGROUND
On 10 September 2021, Al-Ahsa General Health Directorate reported unexpected number of
patients had presented with gastrointestinal symptoms. All the patients gave a history of
sharing a common meal as they ate from dinner was served at the mother's house the day
before.
OBJECTIVE
We investigated to verify the outbreak, determine its magnitude, identify the source and
implement control measures.
METHODS
A retrospective cohort design was conducted. Cases were defined as any person who ate dinner
at the family gathering on the 9th of September 2021 and developed any or a combination of
the following symptoms: diarrhea, vomiting, fever, or abdominal pain within 26 hours of food
consumption. We collected information on demographics, symptoms, and food history using a
semi-structured questionnaire. We reviewed hospital records for symptoms and Vital sings. We
reviewed available laboratory results for cases, we conducted active case search to identify
more cases. statistical analyses were performed using SPSS 21.0.
RESULTS
Twenty subjects were defined as cases (74%) and seven as non-cases (26%). among cases, 16
were females (80%), and 4 were males (20%). The ages ranged between 2–70 years. Among
cases (59.3%) had vomiting, (59.3%) had a fever, (48.1%) developed diarrhea, (25%) abdominal
pain. The incubation period ranged from 10-26 hours (mean 17.8). The relative risks and p-
value were calculated for food items to assess the association between consumption of
individual food items and subsequent illness. Among 8 food items consumed, red pasta with
chicken (Relative Risk RR= 3.14, 95% CI = 3.2-424.6) and pizza (RR= 1.73, 95% CI = 1.74-42.2)
were significantly associated with illness.
CONCLUSIONS
According to the epidemiological investigation, symptoms, incubation period, and laboratory results there might be some differential diagnosis, but we were unable to more definitively identify the source of the outbreak. We recommend more education to the households about food safety