Infectious Diseases 2021

Infectious Diseases 2021

Campylobacter in Sweden

5 July, 2021

Since 1997, the incidence of human campylobacteriosis in Sweden has varied between 65 and 110 cases per 100 000 inhabitants. Most cases are infected abroad, but in 2014–2018 the proportion of domestic infections increased due to several major outbreaks caused by domestically produced chicken meat. The COVID-19 pandemic has resulted in both a record low incidence of Campylobacteriosis and a record high proportion of domestic infections in relation to infections retrieved abroad in 2020. 
The strong association between the prevalence of Campylobacter in broiler flocks and infections among humans makes monitoring in broiler flocks an important tool for early warning. The Swedish Poultry Meat Association has operated a monitoring programme for broiler chicken since 1991. The goal is to achieve an overall annual Campylobacter prevalence of less than 10% in slaughter batches of chicken.
In 2020, thermophilic Campylobacter spp. were detectedin 228 (5.1%) of the 4496 broiler chicken batches tested at slaughter, which is at the same level as in 2019 and less than in years prior to 2019. Among the slaughter batches at the four largest slaughterhouses, which cover 97.2% of the slaughtered chicken, Campylobacter spp, was detected in 4.5% of them. The monthly prevalence of Campylobacter in chicken slaughter batches varied between 0.0% (April) and 12.9% with the highest prevalence in August.
Humans: A total of 3434 cases of campylobacteriosis were reported in 2020. During the last ten-year period, the Swedish chicken production has increased by approximately 30% and the share of fresh chicken meat has increased compared to frozen meat. This has led to a higher amount of potentially contaminated chicken meat at the market, because Campylobacter are sensitive to freezing and therefore more common in fresh than in frozen meat.