Pathotypes and Antimicrobial Susceptibility of Escherichia Coli Isolated from Wild Boar (Sus scrofa) in Tuscany

Pathogenic profile and antimicrobial resistance of Escherichia coli, Escherichia marmotae and Escherichia ruysiae detected from hunted wild boars in Sardinia (Italy)

The objective of this study was to evaluate the occurrence of E. coli in hunted wild boars in Sardinia (Italy) and to further characterize the isolates with Whole Genome Sequencing to assess the genetic relatedness and the presence of virulence and antimicrobial resistance (AMR) genes. Samples were taken from 66 wild boars between 2020 and 2022 slaughtered in five hunting houses. A total of 181 samples were tested, including 66 samples from mesenteric lymph nodes, 66 samples from colon content and 49 samples from carcass surface. Isolates referable to Escherichia species were detected in all of the wild boars sampled. On a selection of 61 isolates, sequencing was conducted and antimicrobial susceptibility was tested. Among these, three isolates were confirmed to be two Escherichia marmotae (cryptic clade V) and one Escherichia ruysiae (cryptic clade III). E. coli pathotypes identified were UPEC (13 %), ExPEC-UPEC (5.6 %) and ETEC (3.7 %). Moreover, 3/6 E. marmotae isolates had typical ExPEC genes. Genetic similarity was observed in isolates collected from animals slaughtered in the same hunting house; this suggests epidemiological links deriving from the presence of animals infected with closely related strains or the result of cross-contamination. Antimicrobial resistance genes were detected in three non-pathogenic E. coli isolates: one isolate had sul2, tet(B), aph(6)-ld and aph(3″)-lb resistance genes and two had the fosA7 gene. This study confirmed that wild boars can act as reservoirs and spreaders of pathogenic Escherichia species and it provides information for future comparative genomic analysis in wildlife. Although isolates showed a limited resistome, the detection of resistance in non-pathogenic isolates underlines the need to monitor antimicrobial resistance in the wild boar population. To the best of our knowledge, this is the first detection of E. mamotae and E. ruysiae isolates in wild boars in Italy and the presence of this pathogen in wildlife and livestock need to be investigated further.

The use of honey bee (Apis mellifera L.) as biological monitors for pathogenic bacteria and antimicrobial resistance: A systematic review

The phenomenon of antimicrobial resistance (AMR) is an increasingly real and relevant health problem. It is essential to verify the spread of this phenomenon in the environment. The European honey bee, Apis mellifera L., is a globally managed pollinator continuously used for biomonitoring thanks to its morphological and behavioural characteristics. During their foraging activities, a large number of honey bees move in the area surrounding the hive within a 1.5 km of radius. Besides, their body covered with hair and bristles are able to intercept pollen and minute particles, such as atmospheric particles, contaminants and microorganisms. For these reasons, A. mellifera L. is widely used as an environmental sentinel, especially for detecting pollutants, pesticides, microorganisms, and AMR. This systematic review aimed to collect and summarize the role of honey bee colonies as a biological monitor of AMR pathogenic bacteria and the environmental spread of antimicrobial resistance genes (ARGs). From honey bees were isolated a wide range of pathogenic and environmental bacteria strains, harbouring AMR and ARGs. However, AMR and ARGs were detected not only in environmental bacteria but also in symbiotic bacteria colonizing the bee gut. This systematic review highlights the employment of potential use of honey bees as AMR sentinel helpful for ecosystem health to implement possible control measures for humans, animals and plants, in the context of the "One-Health" approach.

Presence of Foodborne Bacteria in Wild Boar and Wild Boar Meat-A Literature Survey for the Period 2012-2022

The wild boar is an abundant game species with high reproduction rates. The management of the wild boar population by hunting contributes to the meat supply and can help to avoid a spillover of transmissible animal diseases to domestic pigs, thus compromising food security. By the same token, wild boar can carry foodborne zoonotic pathogens, impacting food safety. We reviewed literature from 2012-2022 on biological hazards, which are considered in European Union legislation and in international standards on animal health. We identified 15 viral, 10 bacterial, and 5 parasitic agents and selected those nine bacteria that are zoonotic and can be transmitted to humans via food. The prevalence of Campylobacter, Listeria monocytogenes, Salmonella, Shiga toxin-producing E. coli, and Yersinia enterocolitica on muscle surfaces or in muscle tissues of wild boar varied from 0 to ca. 70%. One experimental study reported the transmission and survival of Mycobacterium on wild boar meat. Brucella, Coxiella burnetii, Listeria monocytogenes, and Mycobacteria have been isolated from the liver and spleen. For Brucella, studies stressed the occupational exposure risk, but no indication of meat-borne transmission was evident. Furthermore, the transmission of C. burnetii is most likely via vectors (i.e., ticks). In the absence of more detailed data for the European Union, it is advisable to focus on the efficacy of current game meat inspection and food safety management systems.

The Behavior of Some Bacterial Strains Isolated from Fallow Deer Compared to Antimicrobial Substances in Western Romania

(1) Background: The resistance levels of Escherichia coli, Salmonella spp., Pseudomonas spp., Staphylococcus spp., etc., isolated from the nasal cavity and the rectum of Dama dama deer from three hunting grounds in Western Romania were assessed. (2) Methods: The analysis was completed using the diffusimetric method, compliant with CLSI reference standards, and with Vitek-2 (BioMérieux, France), on 240 samples. (3) Results: The results were statistically analyzed (by one-way ANOVA) revealing that in four of the ten E. coli strains isolated from animals, 87.5% (p < 0.001) resistance was found. E. coli strains were resistant to cephalexin (100%); seven strains were resistant to cephalothin and ampicillin; six were resistant to cefquinome and cefoperazone; five were resistant to amoxicillin/clavulanic acid; and four were resistant to ceftiofur. However, E. coli was sensitive to amikacin (100%). The most efficient structures were beta-lactams, amikacin, and imipenem, to which all 47 strains studied (100%) were sensitive, followed by nitrofurantoin, to which 45 strains (95.7%) were sensitive, neomycin, to which 44 strains (93.6%) were sensitive, ceftiofur, to which 43 strains (91.5%) were sensitive, and trimethoprim/sulfamethoxazole and marbofloxacin, to which 42 strains (89.4%) were sensitive. (4) Conclusions: In wild animal populations, where a human presence is frequently reported, including a constant presence of domestic animals, despite the perceived low risk of emerging resistance to antimicrobials, resistance is likely to develop frequently.

Cross-Sectional Survey of Antibiotic Resistance in Extended Spectrum β-Lactamase-Producing Enterobacteriaceae Isolated from Pigs in Greece

Simple Summary

The objective of this study was to investigate, for the first time in Greece, the prevalence of ESBL producers in swine populations and to correlate their occurrence with risk factors. A total of 214 fecal samples were collected from the farms from December 2019 to April 2021. A subset of 78 (78/214, 36.5%) ESBL producers were identified as Escherichia coli (E. coli, 88.5%), Klebsiella pneumoniae spp. pneumoniae (K. pneumoniae, 3.8%), Proteus mirabilis (P. mirabilis, 5.1%), Enterobacter cloacae complex (E. cloacae complex, 1.3%) and Salmonella enterica spp. diarizonae (S. enterica spp. diarizonae, 1.3%). CTX-M, SHV and TEM genes were detected along with genes conferring resistance to fluoroquinolones, aminoglycosides, sulfonamides, trimethoprim, macrolides and colistin. This study displayed high antimicrobial resistance rates in the Greek swine industry, and our results are alarming for both human and animal health.

Abstract

This study aimed to estimate the prevalence of extended-spectrum β-lactamase-producing (ESBL) bacteria in swine. Thus, 214 fecal samples were collected from suckling and weaned piglets from 34 farms in Greece (out of an overall population of about 14,300 sows). A subset of 78 (36.5%) ESBL producers were identified as E. coli (69/78, 88.5%), K. pneumoniae spp. pneumoniae (3.8%), P. mirabilis (5.1%), E. cloacae complex (1.3%) and S. enterica spp. diarizonae (1.3%). Resistance to at least one class of non-β-lactam antibiotics was detected in 78 isolates. Among the E. coli strains, resistance was identified with regard to aminoglycosides (n = 31), fluoroquinolones (n = 49), tetracycline (n = 26) and trimethoprim/sulfamethoxazole (n = 46). Of the three K. pneumoniae spp. pneumoniae, two displayed resistances to aminoglycosides and all were resistant to fluoroquinolones, tetracyclines and trimethoprim/sulfamethoxazole. As for the four P. mirabilis isolates, three had a resistant phenotype for aminoglycosides and all were resistant to imipenem, fluoroquinolones, tetracyclines and trimethoprim/sulfamethoxazole. Molecular characterization of the isolates revealed the presence of CTX-M, SHV and TEM genes, as well as of genes conferring resistance to fluoroquinolones, aminoglycosides, sulfonamides, trimethoprim, macrolides and colistin. High levels of antimicrobial resistance (AMR) were demonstrated in Greek swine herds posing a concern for the efficacy of treatments at the farm level as well as for public health.

Phenotypic and Genetic Characterization of Klebsiella pneumoniae Isolates from Wild Animals in Central Italy

Despite Klebsiella pneumoniae being widely recognized as a nosocomial pathogen, there is a critical lack in defining its reservoirs and sources of infections. Most studies on risk factors have focused on multidrug-resistant (MDR) isolates and clinically-oriented questions. Over a two-year period, we sampled 131 wild animals including mammal and bird species from three regions of Central Italy. All typical colonies isolated from the analytical portions were confirmed by real-time PCR and identified by MALDI-TOF mass spectrometry (MALDI-TOF MS). All confirmed K. pneumoniae isolates were tested for antimicrobial susceptibility to 29 antimicrobials and subjected to whole genome sequencing. Typical colonies were detected in 17 samples (13%), which were identified as K. pneumoniae (n = 16) and as K. quasipneumoniae (n = 1) by MALDI-TOF MS. The antimicrobial susceptibility profile showed that all the isolates were resistant to β-lactams (ceftobiprole, cloxacillin, cefazolin) and tetracycline; resistance to ertapenem and trimethoprim was observed and nine out of 16 K. pneumoniae isolates (56.2%) were classified as MDR. Genomic characterization allowed the detection of fluoroquinolone resistance-associated efflux pumps, fosfomycin and β-lactamase resistance genes, and virulence genes in the overall dataset. The cluster analysis of two isolates detected from wild boar with available clinical genomes showed the closest similarity. This study highlights the link between humans, domestic animals, and wildlife, showing that the current knowledge on this ecological context is lacking and that the potential health risks are underestimated.

Pathogenicity of Shiga toxin-producing Escherichia coli (STEC) from wildlife: Should we care?

Shiga toxin-producing Escherichia coli (STEC) is one of the most frequent bacterial agents associated with food-borne outbreaks in Europe. In humans, the infection can lead to life-threatening diseases. Domestic and wild animals can harbor STEC, and ruminants are the main STEC reservoirs, although asymptomatic. In the present study we have characterized STEC from wildlife (wild boar (n = 56), red deer (n = 101), red fox (n = 37) and otter (n = 92)). Cultivable STEC (n = 52) were isolated from 17% (n = 49) of the faecal samples. All the isolates were non-O157 STEC encoding stx1 (n = 2; 4%) and/or stx2 genes (n = 51; 98%). Only one strain (2%) isolated from red fox had an antibiotic resistant phenotype. However, when the normalized resistance interpretation of epidemiological cutoffs (NRI ECOFFs) were used, 23% (n = 12) of the strains were non-wildtype to at least one of the antibiotics tested. After analysis by pulsed-field gel electrophoresis (PFGE), 20 strains were selected for whole genome sequencing and belonged to the following serotypes: O27:H30 (n = 15), O146:H28 (n = 2), O146:H21 (n = 1), O178:H19 (n = 1), and O103:H2 (n = 1). In addition to stx, all strains encode several virulence factors such as toxins, adhesins, fimbriae and secretion systems, among others. All sequenced genomes carried several mobile genetic elements (MGEs), such as prophages and/or plasmids. The core genome and the phylogenetic analysis showed close evolutionary relationships between some of the STEC recovered from wildlife and strains of clinical origin, highlighting their pathogenic potential. Overall, our results show the zoonotic potential of STEC strains originating from wildlife, highlighting the importance of monitoring their genomic characteristics following a One Health perspective, in which the health of humans is related to the health of animals, and the environment.

Prevalence, risk factors and emergence of extended-spectrum β-lactamase producing-, carbapenem- and colistin-resistant Enterobacterales isolated from wild boar (Sus scrofa) in Tunisia

Antimicrobial resistance (AMR) is recognized as an emerging and growing public health problem worldwide. In Tunisia, knowledge is still limited to domestic animals and humans, and only few data are available regarding the role of wildlife. This research determined the antibiotic susceptibility profiles of Beta-lactamase producing Gram-negative bacteria isolated from the faeces of 110 wild boars (Sus scrofa) in northern Tunisia. Fecal samples, obtained post mortem from boar carcasses, were cultured on MacConkey agar and MacConkey agar containing 2 mg/L of cefotaxime. A total of 102 Enterobacterales isolates were identified from 94(85%) fecal samples. Escherichia coli (56, 54%), Citrobacter freundii (14, 13%), Klebsiella oxytoca (11, 10%), and Klebsiella pneumoniae (7, 6%) were the most predominantly identified Enterobacterales. However, Pantoea spp. (4, 4%), Enterobacter spp. (3,3%), Enterobacter cloacae (1, 1%), Enterobacter gergoviae (2, 2%), Proteus mirabilis (2, 2%), Yersinia sp. (1, 1%), and Citrobacter diversus (1, 1%) were rarely identified. Antimicrobial susceptibility tests revealed that 55% (57/102) of the identified strains were multidrug resistant (MDR). A total of 30% (31/102) of the tested isolates were recognized as Extended Spectrum β-Lactamase (ESBL)-producing strains and blaCTX-M-G1, blaTEM, blaSHV β-lactamases were the main encoding genes revealed. Furthermore, identified isolates showed a high level of AMR, especially for amoxicillin-clavulanic acid (77.67%), ticarcillin-clavulanic acid (71.85%), streptomycin (76.69%), amoxicillin (75.73%), and cephalotin (74.76%). Alarming levels of resistance to colistin (2.9%) and ertapenem (9.7%) were revealed and confirmed by the detection of mcr-1, and bla_IMP and bla_VIM genes, respectively. Various phenotypes of AMR were obtained in this study highlighting the important role of wild boars as hosts and even carriers for several resistant Enterobacterales isolates. This may represents a focal risk factor allowing the transmission of these strains between domestic, wild animals, environment and humans.

A closer look on the variety and abundance of the faecal resistome of wild boar

Antimicrobial resistance (AMR) is a serious problem for public and animal health, and also for the environment. Monitoring and reporting the occurrence of AMR determinants and bacteria with the potential to disseminate is a priority for health surveillance programs around the world and critical to the One Health concept. Wildlife is a reservoir of AMR, and human activities can strongly influence their resistome. The main goal of this work was to study the resistome of wild boar faecal microbiome, one of the most important game species in Europe using metagenomic and culturing approaches. The most abundant genes identified by the high-throughput qPCR array encode mobile genetic elements, including integrons, which can promote the dissemination of AMR determinants. A diverse set of genes (n = 62) conferring resistance to several classes of antibiotics (ARGs), some of them included in the WHO list of critically important antimicrobials were also detected. The most abundant ARGs confer resistance to tetracyclines and aminoglycosides. The phenotypic resistance of E. coli and Enterococcus spp. were also investigated, and together supported the metagenomic results. As the wild boar is an omnivorous animal, it can be a disseminator of AMR bacteria and ARGs to livestock, humans, and the environment. This study supports that wild boar can be a key sentinel species in ecosystems surveillance and should be included in National Action Plans to fight AMR, adopting a One Health approach.

Phenotypic and genotypic resistance to colistin in E. coli isolated from wild boar (Sus scrofa) hunted in Italy

The One Health approach is not only focused on diseases and zoonosis control but also on antimicrobial resistance. As concern this important issue, the problem of plasmid-mediated colistin resistance recently emerged. Few studies reported data about colistin resistance and mcr genes in bacteria from wildlife. In this manuscript, 168 Escherichia coli isolated from hunted wild boar were tested; colistin resistance was evaluated by MIC microdilution method, and the presence of mcr-1 and mcr-2 genes was evaluated by PCR. Overall, 27.9% of isolates resulted resistant to colistin, and most of them showed a MIC value > 256 μg/mL. A percentage of 44.6% of tested E. coli scored positive for one or both genes. In details, 13.6% of isolated harbored mcr-1 and mcr-2 in combination; most of them exhibiting the highest MIC values. Interestingly, 19.6% of mcr-positive E. coli resulted phenotypically susceptible to colistin. Wild boar could be considered a potential reservoir of colistin-resistant bacteria. In the light of the possible contacts with domestic animals and humans, this wild species could play an important role in the diffusion of colistin resistance. Thus, the monitoring programs on wildlife should include this aspect.

Presence and Characterization of Zoonotic Bacterial Pathogens in Wild Boar Hunting Dogs (Canis lupus familiaris) in Tuscany (Italy)

Simple Summary

Wildlife is an important reservoir for several zoonotic pathogens, and wild animals can contribute to disease transmission to humans or domestic animals via direct or indirect contact. In the One Health approach, the role of wildlife and the wild environment in the maintenance and spread of zoonoses has great importance. Domestic dogs (Canis lupus familiaris) employed in wild boar hunts may be a good indicator to evaluate this. This investigation reports the presence of Leptospira spp. and antimicrobial-resistant Salmonella spp. and Yersinia enterocolitica in wild boar hunting dogs in the Tuscany region (Italy). The results obtained suggest that wildlife may be the source of pathogens detected in dogs; indeed, all pathogens may be carried by wild animals, in particular wild boar. This investigation highlights the possible risk for dogs connected to work activities. Furthermore, considering that humans could be exposed to the same pathogens during outdoor activities, constant monitoring seems necessary to evaluate the transmission risk.

Abstract

Domestic dogs (Canis lupus familiaris) used for wild boar (Sus scrofa) hunting may represent incidental hosts for several zoonotic pathogens. This investigation aimed to evaluate the presence of anti-Leptospira antibodies and the occurrence, antimicrobial resistance, and virulence of Salmonella spp., Yersinia enterocolitica, and Listeria monocytogenes in sera and rectal swabs collected from 42 domestic hunting dogs in the Tuscany region (Italy). Regarding Leptospira, 31 out of 42 serum samples (73.8%) were positive and serogroup Pomona was the most detected (71.4%) at titers between 1:100 and 1:400. Four Salmonella isolates (9.52%) were obtained, all belonging to serotype Infantis; two of them showed antimicrobial resistance to streptomycin, while pipB and sopE presence was assessed in all but one isolate. Concerning Yersinia enterocolitica, seven isolates (16.7%) were obtained, six belonging to biotype 1 and one to biotype 4. Resistance to amoxicillin–clavulanic acid, cephalothin, and ampicillin was detected. Biotype 4 presented three of the virulence genes searched (ystA, ystB, inv), while isolates of biotype 1 showed only one gene. No Listeria monocytogenes was isolated from dog rectal swabs. The results suggest that hunting dogs are exposed to different bacterial zoonotic agents, potentially linked to their work activity, and highlight the possible health risks for humans.

Hybrid Atypical Enteropathogenic and Extraintestinal Escherichia coli (aEPEC/ExPEC) BA1250 Strain: A Draft Genome

Diarrheagenic Escherichia coli is the major bacterial etiological agent of severe diarrhea and a major concern of public health. These pathogens have acquired genetic characteristics from other pathotypes, leading to unusual and singular genetic combinations, known as hybrid strains and may be more virulent due to a set of virulence factors from more than one pathotype. One of the possible combinations is with extraintestinal E. coli (ExPEC), a leading cause of urinary tract infection, often lethal after entering the bloodstream and atypical enteropathogenic E. coli (aEPEC), responsible for death of thousands of people every year, mainly children under five years old. Here we report the draft genome of a strain originally classified as aEPEC (BA1250) isolated from feces of a child with acute diarrhea. Phylogenetic analysis indicates that BA1250 genome content is genetically closer to E. coli strains that cause extraintestinal infections, other than intestinal infections. A deeper analysis showed that in fact this is a hybrid strain, due to the presence of a set of genes typically characteristic of ExPEC. These genomic findings expand our knowledge about aEPEC heterogeneity allowing further studies concerning E. coli pathogenicity and may be a source for future comparative studies, virulence characteristics, and evolutionary biology.

Genital Brucella suis Biovar 2 Infection of Wild Boar (Sus scrofa) Hunted in Tuscany (Italy)

Brucellosis is a zoonosis caused by different Brucella species. Wild boar (Sus scrofa) could be infected by some species and represents an important reservoir, especially for B. suis biovar 2. This study aimed to investigate the prevalence of Brucella spp. by serological and molecular assays in wild boar hunted in Tuscany (Italy) during two hunting seasons. From 287 animals, sera, lymph nodes, livers, spleens, and reproductive system organs were collected. Within sera, 16 (5.74%) were positive to both rose bengal test (RBT) and complement fixation test (CFT), with titres ranging from 1:4 to 1:16 (corresponding to 20 and 80 ICFTU/mL, respectively). Brucella spp. DNA was detected in four lymph nodes (1.40%), five epididymides (1.74%), and one fetus pool (2.22%). All positive PCR samples belonged to Brucella suis biovar 2. The results of this investigation confirmed that wild boar represents a host for B.suis biovar. 2 and plays an important role in the epidemiology of brucellosis in central Italy. Additionally, epididymis localization confirms the possible venereal transmission.

Prevalence, Virulence and Antimicrobial Susceptibility of Salmonella spp., Yersinia enterocolitica and Listeria monocytogenes in European Wild Boar (Sus scrofa) Hunted in Tuscany (Central Italy)

Wild boar is an animal the population of which constantly increases in Europe. This animal plays an important role as a reservoir for several pathogens, including three of the most important zoonoses: salmonellosis, yersiniosis and listeriosis. The aim of this investigation was to evaluate the occurrence of antimicrobial-resistant and virulence factor genes of Salmonella spp., Yersinia enterocolitica and Listeria monocytogenes isolated from wild boar in Tuscany (Central Italy). During two consequent hunting seasons (2018/2019 and 2019/2020), rectal swabs, spleens and livers were collected from 287 hunted wild boar to isolate strains. Each isolate was tested to investigate its antimicrobial resistance and to detect virulence factor genes by PCR. Eighteen Salmonella strains (6.27%) were isolated. Of these, 66.7% were resistant to streptomycin, 13.4% to cephalothin, 6.67% to imipenem and one isolate (6.67%) was resistant simultaneously to five antimicrobials. Moreover, the most detected genes were sopE (73.4%), pipB (66.7%), sodCI (53.3%), spvR and spvC (46.7%). In total, 54 (17.8%) Yersinia enterocolitica were isolated; of them, 26 (48.1%), 9 (16.7%), 17 (31.5%), 1 (1.85%) and 1 (1.85%) belonged to biotypes 1, 2, 3, 4 and 5, respectively. All strains (100%) demonstrated resistance to cephalothin and 70.4% to amoxicillin-clavulanic acid, 55.6% to ampicillin, and 37.0% to cefoxitin. Additionally, the most detected genes were ystA (25.9%), inv (24.1%), ail (22.2%), ystB (18.5%) and virF (14.8%). Finally, only one Listeriamonocytogenes isolate (0.35%) was obtained, belonging to serogroup IVb, serovar 4b, and it was found to be resistant to cefoxitin, cefotaxime and nalidixic acid. The results highlighted the role of wild boar as a carrier for pathogenic and antimicrobial-resistant Salmonella spp., Yersinia enterocolitica and Listeria monocytogens, representing a possible reservoir for domestic animals and human pathogens.

Study on Bacteria Isolates and Antimicrobial Resistance in Wildlife in Sicily, Southern Italy

Wild environments and wildlife can be reservoirs of pathogens and antibiotic resistance. Various studies have reported the presence of zoonotic bacteria, resistant strains, and genetic elements that determine antibiotic resistance in wild animals, especially near urban centers or agricultural and zootechnical activities. The purpose of this study was the analysis, by cultural and molecular methods, of bacteria isolated from wild animals in Sicily, Italy, regarding their susceptibility profile to antibiotics and the presence of antibiotic resistance genes. Bacteriological analyses were conducted on 368 wild animals, leading to the isolation of 222 bacterial strains identified by biochemical tests and 16S rRNA sequencing. The most isolated species was Escherichia coli, followed by Clostridium perfringens and Citrobacter freundii. Antibiograms and the determination of resistance genes showed a reduced spread of bacteria carrying antibiotic resistance among wild animals in Sicily. However, since several wild animals are becoming increasingly close to residential areas, it is important to monitor their health status and to perform microbiological analyses following a One Health approach.

Transmission Media of Foodborne Diseases as an Index Prediction of Diarrheagenic Escherichia coli: Study at Elementary School, Surabaya, Indonesia

Foodborne diseases (FBDs) have a large disease burden among children. The major type of FBD in children is diarrhea, caused mainly by contaminated food. One of the diarrhea pathogens is Diarrheagenic Escherichia coli (DEC). The aim of this study was to establish a model of microbial prediction (DEC) in stool, caused by the transmission of FBDs in elementary schoolchildren. An observational analytic study was conducted, with a nested case-control study design. In Stage I, the study population was children in a selected elementary school at Surabaya. The sample size for Stage I was 218 children. In Stage II, the case sample was all children with a positive test for DEC (15 children), and the control sample was all children who had tested negative for DEC (60 children). The result of the laboratory tests showed that the proportion of DEC in children was 6.88% (15 of 218 children) and the proportion of Escherichia coli O157:H7 in children was only 0.46%. The most significant mode of transmission included in the model was the snacking frequency at school and the risk classification of food that was often purchased at school. The formulation of the predicting model of DEC in stool can be used as an early warning against the incidence of FBDs in elementary schoolchildren.