SWEDEN – In an alarming development, Sweden has witnessed a significant increase in Campylobacter infections, with contaminated chicken suspected as the primary driver behind the surge.
Health officials from the Public Health Agency of Sweden, Folkhälsomyndigheten, noted a sudden and early rise in cases during late June and early July, coinciding with an uptick in Campylobacter prevalence in broiler flocks—chickens raised for their meat.
The recent spike in Campylobacter cases has caught health authorities off guard, as it emerged earlier than usual.
Data from the National Veterinary Institute (SVA) revealed a pattern of larger Campylobacter-positive broiler flocks leading up to the outbreak.
The infected individuals span different regions of Sweden, with cases reported across various age groups.
The number of reported non-travel-related cases has been steadily increasing, reaching an average of approximately 20 cases per day and rising.
This compares to the typical peak of 25 to 30 cases per day usually observed in early August during previous years.
The upward trend in domestically infected cases and those with unknown sources of infection rose from around 70 cases per week in June to over 140 cases in the last reported week.
Fresh chicken meat has emerged as the prime suspect as the main source of the Campylobacter outbreak in Sweden.
Previous studies have highlighted a correlation between Campylobacter infection and the consumption of raw or undercooked chicken, with chicken accounting for approximately one-third of reported cases.
The bacteria’s presence in broiler flocks is known to be more prevalent during the summer months, aligning with the seasonal increase in Campylobacter infections among humans.
In 2022, a total of 5,165 cases of campylobacteriosis were reported in Sweden, a significant increase compared to over 4,000 cases in 2021.
While food samples from various sources did not yield any Campylobacter during testing, national and local authorities remain vigilant in their efforts to identify the source of the outbreak.
Good hygiene practices, such as thorough handwashing before and after handling raw chicken, separating raw meat from ready-to-eat foods, and meticulous cleaning of cutting boards and utensils, are recommended to reduce the risk of infection.
As the number of Campylobacter infections continues to rise, health authorities are intensifying efforts to investigate the outbreak’s root cause.
Identifying the source of contamination and implementing effective preventive measures remain top priorities.
The collaboration between the Public Health Agency of Sweden, veterinary institutes, and food businesses is crucial in mitigating the spread of the bacteria and safeguarding public health.
Global trends in Campylobacter infections
Sweden’s recent surge in Campylobacter cases is not an isolated incident, as several countries worldwide have witnessed similar increases in recent years.
Campylobacteriosis is one of the most commonly reported bacterial foodborne illnesses globally, with poultry being a known reservoir for the bacteria.
The average number of outbreaks reported each year from 2004 through 2009 according to the Centers for Disease Control and Prevention (CDC) was 22; it was 31 from 2010 through 2012 and 29 from 2013 through 2017.
Campylobacteriosis is a notifiable disease in Canada, with several hundred cases reported annually. Health Canada, along with provincial and territorial health authorities, actively monitor and address outbreaks to prevent further transmission.
It is the most common cause of bacterial gastroenteritis in the UK and one of the most common bacterial infections reported in the United States. The Centers for Disease Control and Prevention (CDC) estimates that approximately 1.3 million cases occur each year in the U.S.
Efforts are underway internationally to address this public health issue, including improved monitoring and surveillance systems, stricter food safety regulations, and educational campaigns to promote proper food handling and hygiene practices.