ABSTRACT
In August to October 2012, a nationwide outbreak of Salmonella enteritidis phase type (PT) 1B with 53 cases occurred in Finland. Hypothesis generating interviews pointed toward ready-to-eat chicken salad from a Finnish company and at the same time Estonian authorities informed of a S. enteritidis PT 1B outbreak linked to chicken wrap prepared at an Estonian restaurant. We found that chicken salad was associated with the infection (odds ratio (OR) 16·1, 95% confidence interval (CI) 1·7-148·7 for consumption and OR 17·5. 95% CI 4·0-76·0 for purchase). The frozen pre-cooked chicken cubes used in Finnish salad and in Estonian wraps were traced back to a production plant in China. Great Britain made two Rapid Alert Systems for Food and Feed notifications on chicken cubes imported to the UK from the same Chinese production plant. Microbiological investigation confirmed that the patient isolates in Estonia and in Finland were indistinguishable from the strains isolated from chicken cubes in Estonia and in the UK. We recommend that despite certificates for tested Salmonella, food items should be analyzed when Salmonella contamination in outbreak investigations is suspected. In outbreak investigations, electronically implemented case-case study saves time, effort, and money compared with case-control study.
Subject(s)
Disease Outbreaks , Food Microbiology , Frozen Foods/microbiology , Meat/microbiology , Salmonella Food Poisoning/epidemiology , Salmonella enteritidis/physiology , Adolescent , Adult , Aged , Animals , Case-Control Studies , Chickens/microbiology , China , Estonia , Female , Finland/epidemiology , Humans , Incidence , Male , Middle Aged , Salmonella Food Poisoning/microbiology , Salmonella enteritidis/classification , Salmonella enteritidis/isolation & purification , United Kingdom , Young AdultABSTRACT
During one week in July 2012, two patients from the same ward at the municipal hospital in Vaasa, Finland, were diagnosed with septicaemia caused by Listeria monocytogenes. An outbreak investigation revealed eight concomitant cases of febrile gastroenteritis caused by L. monocytogenes on the same ward. Median age of the cases was 82 years and median incubation time for listerial gastroenteritis was 21 h (range 9-107). An additional 10 cases of invasive listeriosis caused by the same outbreak strain were identified across the whole country during the summer of 2012. Environmental investigation at the affected municipal hospital ward revealed ready-sliced meat jelly as the suspected source of the infection. During inspection of the meat jelly production plant, one pooled sample taken from a floor drain and a trolley wheel in the food processing environment was positive for the outbreak strain of L. monocytogenes. After the producer stopped the production of meat jelly, no further cases of listeriosis with the outbreak strain were identified via nationwide surveillance.
Subject(s)
Cross Infection/microbiology , Food Microbiology , Foodborne Diseases/microbiology , Gastroenteritis/microbiology , Listeria monocytogenes/isolation & purification , Listeriosis/microbiology , Meat Products/microbiology , Aged , Aged, 80 and over , Animals , Female , Finland , Gelatin/analysis , Humans , Male , Middle AgedABSTRACT
Over 250 individuals fell ill in five outbreaks caused by Cryptosporidium parvum in Finland, October-November 2012. The cases were connected by lunch meals at restaurants in four different cities. In two outbreaks, the same C. parvumIIdA17G1 subtype was found in patients' stool samples which supports a single source of infection. Frisée salad was the only common food item served at the restaurants, and consumption of lunch salad containing the frisée salad was associated with the illness. Lunch customers who responded that they had eaten lunch salad were three times more likely to have become ill than those who had not answered whether they had eaten the salad or not (RR 2.66; 95% Cl 1.02-6.9, P-value <0.01). Cryptosporidiosis should be considered as a causal agent in long-lasting watery diarrhoea combined with abdominal cramps, and clinical samples should be tested for Cryptosporidium at the same time bacteria and viruses are tested. Measures to prevent contamination of 'ready-to-eat vegetables' with Cryptosporidium oocysts and methods to test frozen food samples should be developed.
Subject(s)
Cryptosporidiosis/parasitology , Cryptosporidium parvum , Disease Outbreaks , Food Parasitology , Vegetables/parasitology , Cryptosporidiosis/epidemiology , Feces/parasitology , Finland/epidemiology , HumansABSTRACT
In 2010, a marked increase in listeriosis incidence was observed in Finland. Listeria monocytogenes PFGE profile 96 was responsible for one-fifth of the reported cases and a cluster of PFGE profile 62 was also detected. Investigations revealed two fishery production plants with persistent Listeria contamination. It appears likely that the plants were at least partly responsible for the increase of listeriosis. Epidemiological investigation revealed that 57% (31/54) of cases with underlying immunosuppressive condition or medication reported eating gravad or cold-smoked fish. Two public notices were issued by THL and Evira informing which groups were most at risk from the effects of listeriosis and should therefore be cautious in consuming certain products. Systematic sampling of foods and adequate epidemiological investigation methods are required to identify the sources of Listeria infections. Continuous control measures at fishery production plants producing risk products are essential.
Subject(s)
Fisheries , Food Contamination/statistics & numerical data , Listeria/classification , Listeriosis/epidemiology , Animals , Disease Outbreaks , Female , Finland/epidemiology , Food Contamination/prevention & control , Food Microbiology , Food-Processing Industry , Humans , Incidence , Listeria/pathogenicity , Listeriosis/diagnosis , Male , Registries , Risk AssessmentABSTRACT
In 2010, 7/44 (16%) reported foodborne outbreaks in Finland were linked with raw beetroot consumption. We reviewed data from the national outbreak registry in order to hypothesize the aetiology of illness and to prevent further outbreaks. In the seven outbreaks, 124 cases among 623 respondents were identified. Consumption of raw beetroot was strongly associated with gastrointestinal illness (relative risk 8â99, 95% confidence interval 6â06-13â35). The illness was characterized by sudden onset of gastrointestinal symptoms; the median incubation time was 40 min and duration of illness 5 h. No common foodborne pathogens or toxins were found in either clinical or beetroot samples, but all tested beetroot samples were of poor quality according to total bacterial counts. Beta-haemolytic Pseudomonas fluorescens was detected in several beetroot samples but its effect on human health is unknown. No outbreaks were reported after the Finnish Food Safety Authority Evira advised against serving raw beetroot in institutional canteens.
Subject(s)
Beta vulgaris/poisoning , Disease Outbreaks , Food Microbiology , Foodborne Diseases/epidemiology , Gastroenteritis/epidemiology , Adolescent , Adult , Aged , Beta vulgaris/microbiology , Cohort Studies , Female , Finland/epidemiology , Foodborne Diseases/microbiology , Gastroenteritis/microbiology , Humans , Male , Middle Aged , Retrospective Studies , Seasons , Young AdultABSTRACT
In October 2011 in Finland, two persons fell ill with symptoms compatible with botulism after having eaten conserved olives stuffed with almonds. One of these two died. Clostridium botulinum type B and its neurotoxin were detected in the implicated olives by PCR and mouse bioassay, respectively. The olives were traced back to an Italian manufacturer and withdrawn from the market. The public and other European countries were informed through media and Europe-wide notifications.