Investigation on food poisoning outbreak associated with consumption of Laksa Kebok in Baling, Kedah

On the 7th of October 2018, Baling District Health Office was alerted on the admission of nine patients to Hospital Gerik, Malaysia for acute gastroenteritis following the consumption of Laksa Kebok, which was bought at Kupang, Baling, Kedah, Malaysia on the 4th of October 2018. The present work thus aimed to confirm and identify the epidemiological characteristics and causative agent related to the outbreak. The investigation team performed active and passive case detection to identify cases involved in this outbreak. A case was defined as any individual who had consumed Laksa Kebok, bought from a stall in Kupang, Baling, Kedah, Malaysia on the 4th of October 2018 onwards, and exhibited symptoms such as diarrhoea, vomiting, abdominal pain, or fever. The team also evaluated the hygienic status of sanitation, food, and water supply at the food premises involved. All clinical and environmental samples were sent for chemical and microbiological tests. An attack rate of 93.2% (n = 83/89) was recorded from a total of 89 people from three states that had consumed the Laksa Kebok. Majority of the cases involved women, with a mean age of 31 years. The most frequent symptoms were diarrhoea (86.7%), fever (65.1%), vomiting (53.0%), and abdominal pain (50.6%). Less than 10% of the cases were hospitalised and treated symptomatically, while two deaths were reported from this outbreak. The epidemic curve showed that the incubation period was between 8.5 and 26 h. The likely causative agent was identified as Salmonella enterica serovar Weltevreden. Inadequate knowledge and improper practices of food handling and preparation had contributed to food contamination. This outbreak was likely caused by the dough used to make the laksa noodles being contaminated by Salmonella Weltevreden. Health education on the importance of food safety and quality for the consumers and food handlers should be developed, improved, and implemented.