Denmark – Outbreak of Salmonella Enteritidis in Denmark

About the disease outbreak

Between 31 March 2022 and 30 July 2022, 21 people have been registered at the Statens Serum Institut who have been infected with the same type of Salmonella Enteritidis (figure 1). Among the sick are 15 men and 6 women. The patients are between 8-59 years old (median age is 28 years). The patients primarily live in the Capital Region and Zealand Region (table 1).

The Statens Serum Institut is working together with the Danish Veterinary and Food Administration and the Norwegian Food Institute DTU on this outbreak to identify the source of infection.

Table 1. Patients with Salmonella Enteritidis in Denmark, March to July 2022, per region (n=21)

The outbreak strain

The bacteria is of the type Salmonella Enteritidis. When whole-genome sequencing of the bacteria isolated from the patients shows that they are very closely related and belong to sequence type 11.

General about salmonella infection

Salmonella is found in animals and can infect humans through food contaminated with the bacteria. Salmonella is a frequent and well-known cause of bacterial intestinal infections in Denmark. There are more than 2,500 different types of salmonella.

Incubation period

The time that passes from being infected to getting symptoms varies from 6-72 hours. Usually 12-36 hours before symptoms appear.

Symptoms

Infection with salmonella typically causes general malaise, diarrhoea, stomach ache, possibly nausea, vomiting and/or fever. The infection is often accompanied by joint pain, muscle pain and headache. Plenty of fluids are important to prevent and treat dehydration from diarrhea and vomiting. In the event of severe diarrheal disease, a doctor should be consulted.