An outbreak investigation into spices sickened 178
people in Sweden has revealed a risk of contaminated products on the market in
other countries.
The first case was reported on 24 December 2014 and
the latest count includes data up to 31 July. More than half of the patients
(113) fell ill after eating at a restaurant linked to using Iwi spice mix sold
by the company Dimpex .
Another firm,
Sevan, issued a withdrawal after Salmonella
found in some of its already opened products but it is not part of the
restaurant outbreak.
Each year, around
two to five cases with Salmonella
Enteritidis phage type (PT) 13a are reported.
In 2014, four of the domestic S. Enteritidis cases were PT 13a, according to the research in
Eurosurveillance. Minor increase could go unnoticed Sweden launched an ‘urgent
inquiry’ in the Epidemic Intelligence Information System (EPIS), on 2 April. No
other country has reported an increase of this specific subtype of S. Enteritidis. However, many European
Union Member States only subtype S. Enteritidis in outbreak situations or
cluster investigations and phage typing or MLVA is not frequent in all EU
countries so a minor increase could go unnoticed.
A Rapid Alert System for Food and Feed (RASFF) alert
by Austria on 26 June reported Salmonella
spp. in a spice mix/seasoning from a manufacturer in Croatia, with a
similar content of dried vegetables as one of the brands implicated in the
Swedish outbreak. The specific batch from which Salmonella spp. was not available in Sweden. The serotype was S. Oranienburg (not S. Enteritidis PT 13a), according to the Austrian Salmonella Reference Centre. In
countries with a high number of reported cases of S. Enteritidis infection, however, a small increase in number of
cases with the outbreak strain could go undetected.
The detection of Salmonella spp. in two different brands
of spice mixes sold in Sweden and the RASFF alert from Austria during the
outbreak period, however, indicates that there could be a common ingredient in
these mixes that are contaminated with Salmonella
spp.
Swedish investigation Initial investigations suggested
the vehicle of infection was most likely a food item with a long shelf life
given the first case was in December. By the end of May, cases increased to 48
and were from over 14 counties. At the beginning of June, Kalmar county
reported a case who had fallen ill after eating at a restaurant, cases
continued to be reported and at the end of the following week six people were
ill. As they all shared the strain, S.
Enteritidis PT 13a. In total, 108 cases were connected to the restaurant,
including staff members. Many had severe symptoms, including bacteremia, and
were hospitalized but exact numbers are not yet known.
Culture analysis require dilution steps and number of
replicates were often necessary to detect and isolate Salmonella spp., indicating very low concentration of the pathogen
in spices.
Source: Eurosurveillance, Volume 20, Issue 30, 30 July
2015 “Outbreak of Salmonella Enteritidis phage type 13A infection in Sweden
linked to imported dried vegetable spice mixes,