Danish pork replaced travel abroad as the main source of Salmonella infections in 2020, according to figures from the Technical University of Denmark’s National Food Institute.

Danes travelled far less this past year because of COVID-19 restrictions, so going abroad was linked to just less than 20 percent of 614 Salmonella cases. Normally, about half of registered infections are travel related.

Danish pork was estimated to have caused 22 percent of illnesses followed by imported pork and duck meat with 9 percent and 6 percent of cases respectively.

A data management issue prevented the statistics being published earlier this year at the same time as the 2020 zoonoses report.

In total, 3,742 Campylobacter cases were recorded in 2020 which was 31 percent fewer than the previous year. Salmonella infections decreased by 45 percent to 614 followed by 448 Shiga toxin-producing E. coli (STEC) infections and 413 Yersinia enterocolitica infections. One reason for the decline was people were less likely to visit the doctor with minor illness symptoms during lockdowns.

Pork increase impacted by other factors
A direct comparison of figures shows a large increase in the number of Salmonella cases caused by Danish pork from 8 percent in 2019 to 22 percent in 2020.

However, the primary reason for this is the dro in travel related cases from 419 to 111 between 2019 and 2020. The actual rise in cases attributed to Danish pork is much smaller.

Of 562 Salmonella isolates from the 614 infections, 462 cases were sporadic and 100 were associated with 10 outbreaks, including 25 as part of an international event. Sporadic cases included 111 travel related, 220 domestic and 141 with unknown travel history.

Overall, 140 of the 562 cases were attributed to Danish produced food, 94 to imported food and 127 to unknown sources.

A total of 35 outbreaks were registered in 2020 compared with 51 in the previous year. The number of people affected was 1,190 with an average of 34 per outbreak and a range of two to 200. More than 1,900 people were sick in 2019.

The number of Salmonella outbreaks was stable with 10 compared to nine in 2019. Five were caused by Salmonella Typhimurium or the monophasic variant but sources were not found.

The largest national outbreak was because of Salmonella Strathcona with 25 cases from May to July. imported tomatoes were suspected to be the cause. An outbreak of Salmonella Kottbus occurred in a restaurant in Copenhagen in June. Of 36 patients, 14 were lab-/confirm/ied. Pea purée was the likely source because of cross-contamination and inadequate temperature control on a hot summer day.