Association between food control inspection grades and regional incidence of infectious foodborne diseases in Finland.

We studied regional food control inspection grades and their relation to regional incidence of domestically acquired foodborne diseases (caused by Campylobacter spp. Salmonella spp. enterohemorrhagic Escherichia coli (EHEC), and Listeria monocytogenes) using food control inspection data of local food business operators and infectious disease data from 2014 to 2019 from Finland. We observed that inferior overall inspection grades were associated with increased incidence of Salmonella infections (p=0.02). Specifically, inferior grades on cleanliness of facilities, surfaces, and equipment were associated with increased incidence of Salmonella infections (p=0.04). For this topical inspection area, a high effect size was also seen for Campylobacter infections (p=0.06). Of the individual inspection items, an association between increased incidence of Campylobacter infections and inferior grades on storage of foodstuffs (p=0.01) and verification of hygiene proficiency (p=0.03) was observed. These results suggest that food control recognizes non-compliances that may predispose to foodborne diseases.

Covid-19 pandemic induced measures in food industry improves food safety as perceived by food business operators in Finland.

This study examines the response of food business operators (FBOs) to the COVID-19 pandemic in relation to food safety and FBOs' experiences of remote inspections performed by official food control. The study was conducted between November and December 2020 with a web-based questionnaire for food processing businesses in Finland. Most of the 60 responded FBOs had made changes to many own-check sectors such as working hygiene (83.4%) and preparedness for special situations (78.0%). Of the FBOs, 47.1-83.0% assessed that the changes in the own-check sectors had a positive impact on food safety and 43.2-100.0% believed that some of the changes would remain after the pandemic. Of the FBOs, 69.8% found on-site inspections at least partially replaceable with video inspection of the production areas. This study shows that, although the pandemic seriously interfered with food production, it also induced FBOs to take measures that promote food safety.

Food fraud detection and reporting by food control officers in Finland.

We studied food fraud detection and the reporting of suspected cases using a questionnaire survey and interviews with Finnish food control officers (FCOs). In total, 95 FCOs responded to the questionnaire, and 17 were interviewed. We found that even though many respondents had either suspected (69.2%) or detected (43.4%) food fraud or other food-related crime during the past five years, 46.8% thought they had no realistic chance of detecting food fraud during inspections. Challenges raised by the FCOs we interviewed included inadequate resources (8/17) and difficulties in inspecting documents or establishing their authenticity (14/17). Moreover, many interviewees highlighted difficulties in assessing whether to inform the police about a suspected case (7/17), and 62% (18/29) of respondents who had detected fraud had not reported it to the police. Training in food fraud detection, increased resources and guidelines on reporting suspected food fraud would improve food fraud detection and harmonize reporting.

Results of routine inspections in restaurants and institutional catering establishments associated with foodborne outbreaks in Finland.

Official food control is intended to ensure food safety in the food business. In Finland, inspections of food service are performed using a 4-point risk-based grading system. This study compared routine inspection results of outbreak and nonoutbreak establishments in restaurants and institutional catering to investigate whether certain inspection results were associated with the occurrence of foodborne outbreaks. Also a more specific sample of outbreak establishments was defined using strength of evidence registered for each outbreak. Grade distributions of specific inspected items were compared separately. No significant differences were seen in restaurants but in institutional catering significantly poorer inspection results (p < 0.05) were detected in items concerning the order and cleanliness of facilities, surfaces and equipment in outbreak establishments. Effective correction of noncompliances in cleanliness of the food handling environment and equipment and constant maintenance of a favourable situation is essential in ensuring a high level of consumer safety in food service.

Factors affecting effectiveness of food control inspections in food production establishments in Finland.

Inspections are an important tool for food control. However, there is a lack of knowledge about how inspection history, interval between inspections, and pre-announcement of the inspection affect compliance with food safety legislation in food production establishments. We used register-based meat, fish, and dairy establishment food control inspection data (5550 inspections from 757 establishments) from Finland in 2016-2019 to study compliance in relation to these factors. Hypothesis was that there is an association between inspection grades and (1) inspection history, (2) interval, and (3) pre-announcement. Results indicate that minor non-compliances that do not impair food safety often precede future more severe non-compliances (5.3% non-compliance rate if full compliance at previous inspection compared to 16.8% non-compliance rate if minor non-compliances at previous inspection [Fisher's exact test, p < 0.0001]), and that longer inspection intervals are associated with a decrease in inspection grades (5.9% difference in inspection intervals for inspection with full compliance compared to inspections with severe non-compliances [Generalized estimating equations, p = 0.02]). In addition, pre-announcement of the inspection affects the inspection grades, severe non-compliances were 2.4 times more common at unannounced inspections compared to pre-announced inspections. To conclude, there is an association between inspection grades and inspection history, inspection interval, and inspection announcement.

Processing plant and machinery sanitation and hygiene practices associate with Listeria monocytogenes occurrence in ready-to-eat fish products.

Listeria monocytogenes causes the foodborne illness listeriosis, which exhibits high fatality among people in risk groups. The incidence of listeriosis has increased in Europe, which raises concerns about L. monocytogenes occurrence in foodstuffs. Ready-to-eat seafood products are considered particularly risky vehicles. Poor hygiene at processing facilities predisposes them to L. monocytogenes contamination, which can be controlled by stringent self-checking system measures. We examined the association of fish-processing plant operational and hygiene practices with the occurrence of L. monocytogenes in vacuum-packaged gravad (cold-salted) and cold-smoked salmon and rainbow trout products. Product sampling of 21 fish-processing plants was carried out, and operational procedures relating to L. monocytogenes control were surveyed using an in-depth risk assessment questionnaire. L. monocytogenes occurred only in sliced and mainly in gravad products of seven fish-processing plants. Shortages in preventive measures were discovered predominantly among the L. monocytogenes positive fish-processing plants. Using generalized linear modeling, we identified the following features associated with L. monocytogenes product contamination: the number of processing machines, deficiencies in the processing environment and machinery sanitation, and staff movement from areas of low toward high hygiene. Furthermore, performing frequent periodic thorough sanitation alongside everyday sanitation practices associated with a decreased risk of product contamination.

Strengthening the efficacy of official food control improves Listeria monocytogenes prevention in fish-processing plants.

Vacuum-packaged cold-salted and cold-smoked fish products are considered typical vehicles for Listeria monocytogenes, the causative agent of the food-borne disease listeriosis, which is increasingly prevalent in the European Union. Efficacy of both the fish processing plant self-checking system and official food control conducted by authorities are crucial for L. monocytogenes prevention in the processing of these risky products. However, the impact of official control on L. monocytogenes prevention in the processing of fish products has not been extensively studied. We investigated the occurrence, control measures, and correction of non-compliances predisposing to L. monocytogenes in Finnish fish processing plants. The following features were associated with L. monocytogenes occurrence: (a) frequency of non-compliances concerning processing machinery, (b) recurrence of non-compliances, and (c) frequency of non-compliances for which official control measures were requested by inspecting authorities. Official control of fish processing plants had focused on risky areas, but non-compliances were common and their correction exhibited deficiencies. We conclude that L. monocytogenes prevention in fish processing can be enhanced by strengthening official food control measures and processing plant compliance. In particular, timely correction of all food safety violations must be improved.

Towards more consistent and effective food control: learning from the views of food business operators.

We surveyed the opinions of Finnish food business operators (FBOs) about the uniformity of local official food control and its importance for dairy, fishery and meat plants. A total of 136 FBOs responded to the questionnaire. Most FBOs considered official food control to be important for food safety and were generally satisfied with its quality. However, they often did not perceive official food control as being uniform, and 23% even considered it arbitrary. Small-sized FBOs were particularly critical of the relevance of control actions. The better the FBOs assessed their cooperation with the inspector, the higher they assessed the quality, uniformity and benefits of official food control. The cooperative approach in control practices should be emphasized to support the positive views of FBOs about official food control, thus promoting food safety. Cross-audits among local food control units are recommended to improve the FBOs' experience of uniformity of food control.

Reduction of enteropathogenic Yersinia in the pig slaughterhouse by using bagging of the rectum.

To evaluate the effectiveness of bagging of the rectum in mitigating the contamination of carcasses with enteropathogenic Yersinia at the slaughterhouse and to estimate the hidden prevalences of these pathogens in different farm types and capacities, samples from pigs, carcasses, and slaughterhouse environment were collected, and a Bayesian probability model was constructed. In addition, the contamination routes were studied with molecular typing of the isolated strains. According to the model, bagging of the rectum reduced carcass contamination significantly with pathogenic Yersinia enterocolitica, but not with Yersinia pseudotuberculosis, and alone it was insufficient to completely prevent the carcass contamination with enteropathogenic Yersinia. The hidden prevalence of pathogenic Y. enterocolitica was higher at high production capacity than it was in low production capacity, but the 95 % credible intervals overlapped. Slaughterhouse environments can contaminate carcasses with enteropathogenic Yersinia, but the plausible main contamination source is the pig carrying the pathogen.

[Food control--the mainstay of food safety]. / Elintarvikevalvonta--elintarviketurvallisuuden tukipilari.

The main responsibility of the local food control lies in the local food and environmental health units. The producer is responsible for the safety of the food produced, and applies an in-house control system to achieve this goal. The local food safety authority evaluates the in-house control system and assures that it is targeted to the most critical steps in the production to efficiently minimize the food safety risks. The main challenges in implementing efficient food control system are the variability in the knowledge of the producer about food hygiene, inadequate resources in control units and harmonization of the control measures in national level.

Pilot-scale continuous ultrasonic cleaning equipment reduces Listeria monocytogenes levels on conveyor belts.

Ultrasonic cleaning of a conveyor belt was studied by building a pilot-scale conveyor with an ultrasonic cleaning bath. A piece of the stainless steel conveyor belt was contaminated with meat-based soil and Listeria monocytogenes strains (V1, V3, and B9) and incubated for 72 h to allow bacteria to attach to the conveyor belt surfaces. The effect of ultrasound with a potassium hydroxide-based cleaning detergent was determined by using the cleaning bath at 45 and 50 degrees C for 30 s with and without ultrasound. The detachment of L. monocytogenes from the conveyor belt caused by the ultrasonic treatment was significantly greater at 45 degrees C (independent samples t test, P < 0.001) and at 50 degrees C (independent samples t test, P = 0.04) than without ultrasound. Ultrasonic cleaning efficiency was tested with different cleaning durations (10, 15, 20, and 30 s) and temperatures (30, 45, and 50 degrees C). The differences in the log reduction between cleaning treatments were analyzed by analysis of variance with Tamhane's T2 posthoc test using SPSS (Chicago, IL). The lengthening of the treatment time from 10 to 30 s did not significantly increase the detachment of L. monocytogenes (ANOVA 0.633). At 30 degrees C and at the longest time tested (30 s), the treatment reduced L. monocytogenes counts by only 2.68 log units. However, an increase in temperature from 30 to 50 degrees C improved the effect of the ultrasonic treatment significantly (P < 0.01). Ultrasonic cleaning for 10 s at 50 degrees C reduced L. monocytogenes counts by more than 5 log units. These results indicate that ultrasonic cleaning of a conveyor belt is effective even with short treatment times.

An 8-year surveillance of the diversity and persistence of Listeria monocytogenes in a chilled food processing plant analyzed by amplified fragment length polymorphism.

Contamination routes of Listeria monocytogenes were examined in a chilled food processing plant that produced ready-to-eat and ready-to-reheat meals during an 8-year period by amplified fragment length polymorphism (AFLP) analysis. A total of 319 L. monocytogenes isolates were recovered from raw materials (n = 18), the environment (n = 77), equipment (n = 193), and products (n = 31), and 18 different AFLP types were identified, five of which were repeatedly found to be persistent types. The three compartments (I to III) of the plant showed markedly different contamination statuses. Compartment I, which produced cooked meals, was heavily contaminated with three persistent AFLP types. AFLP type A1 dominated, and it comprised 93% of the isolates of the compartment. Compartment II, which produced uncooked chilled food, was contaminated with four persistent and five nonpersistent AFLP types. The equipment of compartment III, which produced cooked ready-to-reheat meals, was free of contamination. In compartments that produced cooked meals, the cleaning routines, product types, and lack of compartmentalization seemed to predispose production lines to persistent contamination. The most contaminated lines harbored L. monocytogenes in coolers, conveyors, and packing machines. Good compartmentalization limited the flow of L. monocytogenes into the postheat-treatment area and prevented the undesired movement of equipment and personnel, thus protecting the production lines from contamination. In compartment II, grated cheese was shown to cause product contamination. Therefore, special attention should be paid to continuous quality control of raw ingredients when uncooked ready-to-eat foods are produced. In compartment II, reconstruction of the production line resulted in reduced prevalence rates of L. monocytogenes and elimination of two persistent AFLP types.

Meat inspection education in Finnish veterinary curriculum.

This article describes the Finnish meat-inspection curriculum and presents an expert-panel evaluation of meat-inspection education. The work tasks of the meat-inspection veterinarian are challenging and include classical meat inspection, meat hygiene, hygiene control, and animal disease and welfare. The meat-inspection veterinarian is not only an inspector, which by itself is very demanding, but also an expert or "consultant" on food safety. The significant role of the meat-inspection veterinarian in society puts high demands on meat-inspection education, which should provide veterinary students with sufficient tools to perform meat inspection and hygiene control in slaughterhouses, cutting premises, and further processing plants. To be of high quality, such education must be evaluated from time to time. An expert panel evaluated Finnish undergraduate meat-inspection education and found that it provides veterinary students with good knowledge of meat inspection. The structure of the curriculum, with theoretical studies followed by four weeks of practice in a slaughterhouse, was considered vital for learning and for creating interest in meat inspection. The evaluation also revealed that certain subjects should receive greater emphasis and some new subjects should be introduced. Hygiene-control tasks, in particular, have increased and should receive more emphasis in education. Personnel management and interaction skills should be introduced into the curriculum as these skills influence all the duties of the meat-inspection veterinarian. This article outlines the subjects to be included in the modern, high-quality meat-inspection curriculum recommended by the expert panel.

Ultrasonic cleaning of conveyor belt materials using Listeria monocytogenes as a model organism.

Persistent Listeria monocytogenes contamination of food industry equipment is a difficult problem to solve. Ultrasonic cleaning offers new possibilities for cleaning conveyors and other equipment that are not easy to clean. Ultrasonic cleaning was tested on three conveyor belt materials: polypropylene, acetal, and stainless steel (cold-rolled, AISI 304). Cleaning efficiency was tested at two temperatures (30 and 45 degrees C) and two cleaning times (30 and 60 s) with two cleaning detergents (KOH, and NaOH combined with KOH). Conveyor belt materials were soiled with milk-based soil and L. monocytogenes strains V1, V3, and B9, and then incubated for 72 h to attach bacteria to surfaces. Ultrasonic cleaning treatments reduced L. monocytogenes counts on stainless steel 4.61 to 5.90 log units; on acetal, 3.37 to 5.55 log units; and on polypropylene, 2.31 to 4.40 log units. The logarithmic reduction differences were statistically analyzed by analysis of variance using Statistical Package for the Social Sciences software. The logarithmic reduction was significantly greater in stainless steel than in plastic materials (P < 0.001 for polypropylene, P = 0.023 for acetal). Higher temperatures enhanced the cleaning efficiency in tested materials. No significant difference occurred between cleaning times. The logarithmic reduction was significantly higher (P = 0.013) in cleaning treatments with potassium hydroxide detergent. In this study, ultrasonic cleaning was efficient for cleaning conveyor belt materials.

Factors associated with Listeria monocytogenes contamination of cold-smoked pork products produced in Latvia and Lithuania.

A total of 312 samples of sliced, vacuum packaged, cold-smoked pork from 15 meat processing plants in Latvia and Lithuania, obtained over a 15-month period from 2003 until 2004, were analyzed for the presence of Listeria monocytogenes at the end of their shelf-life. Overall, 120 samples (38%) tested positive for L. monocytogenes. Despite the long storing period, the levels of L. monocytogenes in cold-smoked pork products were low. Manufacturing processes were studied at seven meat processing plants. A new approach with a logistic multivariable regression model was applied to identify the main factors associated with L. monocytogenes contamination during the manufacturing of cold-smoked pork products. Brining by injection was a significant factor (odds ratio 10.66; P<0.05) for contamination of product with L. monocytogenes. Moreover, long cold-smoking times (> or = 12 h) had a significant predictive value (odds ratio 24.38; P<0.014) for a sample to test positive for L. monocytogenes. Pulsed-field gel electrophoresis results indicated that various sources of L. monocytogenes contamination existed over periods of time in several meat processing plants. In two meat processing plants, persistent L. monocytogenes strains belonging to serotypes 1/2a and 1/2c were found.

Raw and processed fish show identical Listeria monocytogenes genotypes with pulsed-field gel electrophoresis.

A total of 257 raw fish samples at two different sites were examined for the presence of Listeria monocytogenes. The prevalence of L. monocytogenes was 4%. From 11 positive samples, nine different L. monocytogenes pulsed-field gel electrophoresis genotypes were recovered. From nine pulsotypes recovered from raw fish and 32 pulsotypes shown by 101 fish product isolates, two raw fish and fish product pulsotypes were indistinguishable from each other. Although the prevalence of L. monocytogenes in raw fish is low, the range of L. monocytogenes strains entering the processing plant in large amounts of raw material is wide. This indicates that the raw material is an important initial contamination source of L. monocytogenes in fish processing plants. This postulation is supported by the identical pulsotypes recovered from both raw and processed fish. Some L. monocytogenes strains entering a plant may thus contaminate and persist in the processing environment, causing recurrent contamination of the final products via processing machines.

Prevalence and genetic diversity of Listeria monocytogenes in the tonsils of pigs.

This study was set up to establish the prevalence of Listeria monocytogenes in the tonsils of sows and fattening pigs from five Finnish slaughterhouses and to evaluate the genetic similarity of L. monocytogenes strains isolated from the tonsils. A total of 271 pig tonsils (132 tonsils from fattening pigs and 139 from sows) from five different slaughterhouses in various parts of Finland were studied from June 1999 to March 2000. Overall, 14 and 4% of pig tonsils harbored L. monocytogenes and Listeria innocua, respectively. The prevalence of L. monocytogenes in tonsils of fattening pigs (22%) was significantly higher than in sows (6%). The isolates (n = 38) recovered from tonsils showed a wide genetic diversity by means of 24 different pulsed-field gel electrophoresis (PFGE) types presented by the strains. Moreover, in numerical analyses of restriction patterns, no association was found between the clustering of strains and the slaughterhouses, and strains showing a similar PFGE type were recovered from pigs of different slaughterhouses. The high prevalence of L. monocytogenes showing various PFGE types in the tonsils of pigs could indicate a potential source of contamination of pluck sets, carcasses, and the slaughterhouse environment and of subsequent processing steps.

Characterisation of persistent and sporadic Listeria monocytogenes strains by pulsed-field gel electrophoresis (PFGE) and amplified fragment length polymorphism (AFLP).

This study was set up to evaluate the genetic similarity or dissimilarity of persistent and sporadic Listeria monocytogenes strains existing in eleven food processing facilities, including fish, dairy, meat and poultry processing plants. In each plant persistent and sporadic strains were selected on the basis of PFGE typing results. A total of 17 strains representing persistent strains and 38 sporadic strains originating from eleven food processing plants were included in the study. PFGE macrorestriction patterns of persistent and sporadic strains from different processing plants were compared and the strains were further studied by amplified fragment length polymorphism (AFLP), being a characterisation method giving more whole genome based information. The 17 persistent and 38 sporadic strains showed 14 and 35 pulsotypes, 14 and 28 AFLP types, respectively. The combination of PFGE and AFLP typing results yielded a total of 48 genotypes. Thirteen of 15 genotypes presented by persistent strains were only associated with persistent strains and similarly 94% (33/35) of genotypes showed by sporadic strains were recovered among sporadic strains only. Our results showed that L. monocytogenes strains causing persistent contamination differ from sporadic strains. In AFLP analysis persistent strains did not, however, form any specific clusters and neither was there any difference between the known two genomic groups. These results indicate that even though persistent strains differ from sporadic strains there seems not to be any specific evolutional lineage of persistent strains.

Persistent and nonpersistent Listeria monocytogenes contamination in meat and poultry processing plants.

Contamination analysis of persistent and nonpersistent Listeria monocytogenes strains in three meat processing plants and one poultry processing plant were performed in order to identify factors predisposing to or sustaining persistent plant contamination. A total of 596 L. monocytogenes isolates were divided into 47 pulsed-field gel electrophoresis (PFGE) types by combining the restriction enzyme patterns of AscI (42 patterns) and ApaI (38 patterns). Persistent and nonpersistent strains were found in all plants. Nonpersistent PFGE types were found mostly at one sampling site, with the processing environment being the most common location, whereas the persistent strains were found at several sampling sites in most cases. The processing machines were frequently contaminated with persistent L. monocytogenes PFGE types, and it was of concern that surfaces having direct contact with the products were contaminated. The role of the processing machines in sustaining contamination and in contaminating the products appeared to be important because the final product of several processing lines was contaminated with the same L. monocytogenes PFGE type as that found in the processing machine. The proportion of persistent PFGE types in heat-treated products was eight times higher than in the raw products, showing the importance of the persistent PFGE types as contaminants of the final heat-treated products. The contamination status of the processing lines and machines appeared to be influenced by the compartmentalization of the processing line, with poor compartmentalization increasing L. monocytogenes contamination. The separation of raw and post-heat treatment areas seemed especially important in the contamination status of post-heat treatment lines.

Typing of Listeria monocytogenes isolates originating from the food processing industry with automated ribotyping and pulsed-field gel electrophoresis.

A total of 486 Listeria monocytogenes isolates originating from 17 Finnish food processing plants (representing meat, poultry, fish, and dairy production) were collected and typed by automated ribotyping using EcoRI as the restriction enzyme. The isolates were divided into 16 different ribotypes (RTs). Some of these isolates (121), representing all EcoRI types and 16 food plants, were subjected to ribotyping with the PvuII enzyme, to pulsed-field gel electrophoresis (PFGE) typing with AscI and SmaI restriction enzymes, and to serotyping with O-antigen antisera. Nineteen ribotypes were generated with PvuII, 42 macrorestriction patterns were generated with AscI and 24 with SmaI, and three serotypes were generated with antisera. When the results were combined, the overall number of RTs was 23, and that of the PFGE types was 46. Thus, the overall discrimination power of PFGE was higher (discrimination index [DI] 0.966) than that of ribotyping (DI 0.906). The most common serotype (90.1% of the isolates) was 1/2, and isolates of serotype 4 (3.3%) were rare. There was no connection between food sectors and RTs or PFGE types, but PFGE indicated the single plants (78.3% of the types) better than ribotyping (56.5%). On the basis of its automation and on the availability of identification databases, automated ribotyping had some advantages over PFGE. Overall, automated ribotyping can be considered a practical and rapid tool when Listeria contamination is suspected and when screening a large number of isolates is necessary, e.g., when tracing contamination sources. However, in cases of outbreaks, the identical patterns must be confirmed by PFGE, which is a more discriminatory method.