Category Archives: Zoonosis

Research – Microbiology and Epidemiology of Escherichia albertii—An Emerging Elusive Foodborne Pathogen


Escherichia albertii, a close relative of E. coli, is an emerging zoonotic foodborne pathogen associated with watery diarrhea mainly in children and immunocompromised individuals. E. albertii was initially classified as eae-positive Hafnia alvei, however, as more genetic and biochemical information became available it was reassigned to its current novel taxonomy. Its infections are common under conditions of poor hygiene with confirmed transmission via contaminated water and food, mainly poultry-based products. This pathogen has been isolated from various domestic and wild animals, with most isolates being derived from birds, implying that birds among other wild animals might act as its reservoir. Due to the absence of standardized isolation and identification protocols, E. albertii can be misidentified as other Enterobacteriaceae. Exploiting phenotypes such as its inability to ferment rhamnose and xylose and PCR assays targeting E. albertii-specific genes such as the cytolethal distending toxin and the DNA-binding transcriptional activator of cysteine biosynthesis encoding genes can be used to accurately identify this pathogen. Several gaps exist in our knowledge of E. albertii and need to be bridged. A deeper understanding of E. albertii epidemiology and physiology is required to allow the development of effective measures to control its transmission and infections. Overall, current data suggest that E. albertii might play a more significant role in global infectious diarrhea cases than previously assumed and is often overlooked or misidentified. Therefore, simple, and efficient diagnostic tools that cover E. albertii biodiversity are required for effective isolation and identification of this elusive agent of diarrhea. View Full-Text

Research – Introduction to the Special Issue: Microbiological Safety and Quality of Foods


Recent shifts in food production, processing and distribution, linked to the globalization of the food trade and the need to meet new consumers habits, are continuously challenging global food systems. Every effort is being made to ensure healthy and safe, food that is crucial to guarantee public health and wellbeing.
Despite the advancements in food safety management, foodborne diseases (FBD) still remain an important problem worldwide, with a significant negative impact on human health and countries’ economies and development. It has been determined that food unsafe for consumption causes 600 million cases of FBD every year, and 25% of all foods produced globally are lost due to microbial spoilage. Serious outbreaks have occurred, involving both developing and industrialized countries, showing how food safety is a transnational challenge and that a strong joint commitment between food safety authorities is needed.
Despite this awareness, the full extent of the impact of food contamination is still unknown. Foodborne contaminants are numerous, including viruses and bacteria, parasites, chemicals, toxins and allergens that cause a wide range of conditions. Globally, FBD caused by bacteria are more common than those caused by viruses and parasites. [1]. Moreover, between one-third and one-half of all human infectious diseases have a zoonotic origin. Among bacteria, Campylobacter, followed by Salmonella, are the major etiological agents of FBD, while, among viruses, norovirus is the foremost enteric pathogen of foodborne disease worldwide [2].
The most common foodborne parasites instead are protozoa such as Cryptosporidium spp., Giardia intestinalis and Toxoplasma gondii; roundworms such as Trichinella spp. and Anisakis spp.; and tapeworms such as Diphyllobothrium spp. and Taenia spp. [3]. In particular, Anisakiasis is an emerging zoonosis caused by the fish parasitic nematode Anisakis. Humans are accidental hosts that become infected by eating raw or undercooked fish that contain viable Anisakis spp. larvae.
The major determinants for the incidence of FBD are unsafe raw food, abused temperature, inadequate storage, improper handling, undercooking and cross contamination [4]. Food from animal sources, fresh produce and ready-to-eat (RTE) foods are the most at risk. In particular, RTE foods are an emerging issue concerning food safety. Furthermore, they have been demonstrated to contain antimicrobial-resistant strains. Since these products are consumed without any further treatment, they could serve as a vector for the spread of antibiotic-resistant microorganisms, posing a significant threat to public health [5].
The importance of these topics is documented by the increasing number of papers published related to Food Safety. In a basic search using PubMed database, from 1945 to 2021, selecting as the search topic “Microbiological food safety”, a total of 54,210 results were obtained.
Although the first articles concerning microbiological food safety date from 1946, and since then a dozen articles appear in the following years, it is not until 1965 that a significant number of articles are published every year. Figure 1 shows the evolution of the number of papers per year (from 1965 to 2021) published regarding Microbiological food safety. As can be seen in this figure, approximately 80% of these papers have been published in the last 20 years, and the number continues to rise, revealing an increasing and ever-present interest towards the topic addressed in this Special Issue.
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Research – Prevalence of Mycobacterium bovis in milk on dairy cattle farms: An international systematic literature review and meta-analysis

Science Direct

Bovine tuberculosis, caused by Mycobacterium bovis (M. bovis), is a globally distributed chronic disease of animals. The bacteria can be transmitted to humans via the consumption of unpasteurised (raw) milk, thus representing an important public health risk. To investigate the risk of zoonotic transmission of M. bovis via raw milk, this study systematically reviewed published studies to estimate the prevalence of M. bovis in on-farm bulk-tank milk (BTM) and individual cow’s milk (IM) by meta-analysis.

In total, 1,339 articles were identified through seven electronic databases and initially screened using titles and abstracts. The quality of 108 potentially relevant articles was assessed using full texts, and 67 articles comprising 83 studies (76 IM and 7 BTM), were included in the meta-analysis. The prevalence of M. bovis in IM and BTM was summarised according to the diagnostic test used, and the tuberculin skin test (TST) infection status of the individual cows (for IM) or herds (for BTM). Heterogeneity was quantified using the I-squared statistic. Prediction intervals (95% PIs) were also estimated.

For IM, the overall prevalence was summarised at 5% (95%CI: 3%–7%). In TST positive cows, prevalence was summarised at 8% (95%CI: 4%–13%). For BTM, the overall prevalence independent of individual herd TST infection status was summarised at 5% (95%CI: 0%–21%).

There was considerable heterogeneity evident among the included studies, while PIs were also wide. Inconsistency in the quality of reporting was also observed resulting in missing information, such as the TST infection status of the individual animal/herd. No study reported the number of M. bovis bacteria in test-positive milk samples. Several studies reported the detection of M. tuberculosis and M. africanum in milk.

Despite international efforts to control tuberculosis, this study highlights the risk of zoonotic transmission of M. bovis via unpasteurised milk and dairy products made using raw milk.

Research – Zoonoses and foodborne outbreaks guidance for reporting 2021 data


This technical report of the European Food Safety Authority(EFSA)presents the guidance to reporting European Union(EU)Member States and nonMember States in data transmission using extensible markup language (XML)data transfer covering the reporting of prevalence data on zoonoses and microbiological agents and contaminants in food, foodborne outbreak data, animal population data and disease status data. For data collection purposes, EFSA has created the Data Collection Framework(DCF)application. The present report provides data dictionaries to guide the reporting of information deriving from 2021under the framework of Directive 2003/99/EC, Regulation (EU) 2017/625andCommission Implementing Regulation (EU) 2019/627.The objective is to explain in detail the individual data elements that are included in the EFSA data models to be used for XML data transmission through the DCF. In particular, the data elements to be reported are explained, including information about the data type, a reference to the list of allowed terms and any additional business rule or requirement that may apply.

Research – Wild Boars as Reservoir of Highly Virulent Clone of Hybrid Shiga Toxigenic and Enterotoxigenic Escherichia coli Responsible for Edema Disease, France


Edema disease is an often fatal enterotoxemia caused by specific strains of Shiga toxin–producing Escherichia coli (STEC) that affect primarily healthy, rapidly growing nursery pigs. Recently, outbreaks of edema disease have also emerged in France in wild boars. Analysis of STEC strains isolated from wild boars during 2013–2019 showed that they belonged to the serotype O139:H1 and were positive for both Stx2e and F18 fimbriae. However, in contrast to classical STEC O139:H1 strains circulating in pigs, they also possessed enterotoxin genes sta1 and stb, typical of enterotoxigenic E. coli. In addition, the strains contained a unique accessory genome composition and did not harbor antimicrobial-resistance genes, in contrast to domestic pig isolates. These data thus reveal that the emergence of edema disease in wild boars was caused by atypical hybrid of STEC and enterotoxigenic E. coli O139:H1, which so far has been restricted to the wildlife environment.

Slovakia – Report on zoonoses, foodborne diseases and waterborne diseases in the Slovak Republic in 2020



The protection of human and animal health can only be achieved through the active cooperation of experts in the field of control and research in the human and veterinary field. The report on zoonoses, foodborne diseases and waterborne diseases in the Slovak Republic for 2020 contains data from official inspections carried out in the field of agriculture and health care, as well as from research institutes and universities. The preparation of the report was coordinated by the National Contact Point for Scientific and Technical Cooperation with the European Food Safety Authority (EFSA EFSA), which is established at the Department of Food Safety and Nutrition of the Ministry of Agriculture and Rural Development of the Slovak Republic (MPRV SR).

The report serves as a basis for the EFSA NCB and scientific experts to set priorities and own national food safety risk assessments. At the same time, the report serves as one of the bases for the Community risk assessment carried out by the European Food Safety Authority (EFSA). Scientific risk assessment is the basis for risk management. The report describes the situation in  35 zoonotic agents, 5 foodborne diseases (ie foodborne diseases) without zoonotic potential and 4 waterborne pathogens. Of the 44 agents monitored, 23 are bacterial, 10 parasitic, 10 viral and prion.

It presents the summary results of examinations and tests performed in 2020 in the Slovak Republic and the evaluation of the national epidemiological situation in humans and animals with a focus on trends and sources of zoonotic and foodborne diseases.

The report presents the summary results of examinations and tests carried out in 2020 and an assessment of the national epidemiological situation in humans and animals , focusing on trends and sources of zoonotic and foodborne diseases . The number of monitored authors, cooperating organizations and experts is growing every year. A wide team of more than 70 experts from 24 scientific and control organizations in the Slovak Republic took part in its elaboration .

In 2020, 17,067 human diseases caused by the study agents were reported, with 29.1% related to campylobacteriosis, 20.9% to Clostridium dificille and 20.4% to salmonellosis. Rotavirus 11.6%, Norwalk virus 5.1%, Borrelia burgdorferi sl 5.6% and  Escherichia coli 1.2% also contributed to a higher percentage of diseases.

Seven of the study agents caused 380 human epidemics, of which 56.6% were salmonellosis, 23.2% were campylobacteriosis and 12.6% of epidemics were caused by rotavirus. Norwalk virus accounted for 5.5%, tick-borne encephalitis virus 1.3%, shigella and 0.5% and yersinia 0.3%.  

35,957 food samples were examined for the presence of 15 pathogens with a positive finding in 2.2% of samples. Higher percentages of positive findings were in  Yersinia spp. 48.1%, Enterococcus spp. 46.3% and  Vibrio spp. 31.8%.

The presence of 30 pathogens was monitored in 2,483,239 samples originating from livestock and wild animals, pets and zoos taken as part of official control, preventive monitoring, research, as well as from sick or dead animals. Positive findings accounted for 0.1% of samples. Higher percentages of positive findings were recorded for  Aeromonas spp. 59.3%, Clostridium spp. 55.4%, Francisella tularensis 50.4%, Babesia spp. 41.1%, Dirofilaria spp. 34.8%, Campylobacter spp. 18.3%, Yersinia spp. 18.3%, Staphylococcus aureus 18.1%, hepatitis E virus 14.1%, Listeria monocytogenes  11.8%, Toxocara spp. 10.5%.

Feed – 385 samples were examined for the presence of Salmonella spp. (1.5% positive samples), Escherichia coli (60.0% positive samples) and Clostridium spp.

(1.7% positive samples).

35,746 water samples were examined for the presence of 9 agents, of which 7.4% were positive, of which Legionella spp. 47.1% and Vibrio spp. 39.5%.

44,633 samples from the environment were examined for the presence of 8 pathogens, of which 2.3% were positive, of which Legionella spp. 36.0%, Vibrio spp. 6.8%,  E.coli 3.6% and  Enterococcus spp. 2.6%.

The report also includes the results of examinations for the resistance of microorganisms to antimicrobials, which has a growing trend worldwide and poses a real danger in the treatment of infections. Microbial resistance was monitored in Salmonella spp., E. coli , Campylobacter spp., Staphylococcus aureus and  Enterococcus spp.

The comprehensive report, which will be published as a publication, has a length of more than 130 pages, will be published in printed form, as a publication with an assigned ISBN. Summaries of individual chapters will be translated into English and published in an electronic version as a publication with an assigned ISBN.

See the appendices for more information.

Attachments (downloadable documents)


Norway – The Norwegian Zoonoses Report 2020


The occurrence of most zoonotic pathogens in animals was stable in 2020 compared to previous years. The occurrence in humans, however, decreased in 2020 due to the COVID-19 situation. The decrease was highest in campylobacteriosis, salmonellosis and E. coli (EHEC/VTEC) infections, mainly due to less travel associated cases. Introduction The Zoonosis Report is published annually in Norway in accordance with the requirements of the EU Council Directive 2003/99/EC. In addition, data on specified zoonoses in feed, animals and food are reported to the European Food Safety Authority (EFSA). Corresponding data from humans are reported to the European Center for Disease Control (ECDC).

These two European institutions compile an annual European zoonosis report based on the received data: Norwegian Veterinary Institute (NVI) is responsible for reporting of Norwegian data to EFSA, while the Norwegian Institute of Public Health (NIPH) reports Norwegian data to ECDC. The Zoonosis Report is written by the NVI in collaboration with the Norwegian Food Safety Authority (NFSA) and NIPH.

Click to access 2021_63%20Zoonoserapporten%202020.pdf

Research – Peanut Skins as a Natural Antimicrobial Feed Additive to Reduce the Transmission of Salmonella in Poultry Meat Produced for Human Consumption

Journal of Food Protection

Salmonella is the leading cause of bacterial foodborne zoonoses in humans. Thus, the development of strategies to control bacterial pathogens in poultry is essential. Peanut skins, a considerable waste by-product of the peanut industry is discarded and of little economic value. However, peanut skins contain polyphenolic compounds identified that have antimicrobial properties. Hence, we aim to investigate the use of peanut skins as an antibacterial feed additive in the diets of broilers to prevent the proliferation of Salmonella Enteritidis (SE). One hundred sixty male hatchlings (Ross 308) were randomly assigned to, (1) PS: peanut skin diet without SE inoculation (2) PSSE: peanut skin diet and SE inoculation 3) CON: control diet without SE inoculation (4) CONSE: control diet with SE inoculation. Feed intake and body weights were determined at week 0 and 5. On days 10 and 24 post hatch, 3 birds/pen (24 total) from each treatment group were euthanized and the liver, spleen, small intestine, and ceca were collected. The weights of the liver, spleen and ceca were recorded. Organ invasion was determined by counting SE colonies. Each pen served as an experimental unit and was analyzed using a t-test. Performance data was analyzed in a completely randomized design using a general linear mixed model to evaluate differences. There were no significant differences ( P > 0.05) in weekly average pen body weight, total feed consumption, bird weight gain and feed conversion ratio between the treatment groups. There were no significant differences in SE CFU/g for fecal, litter or feed between treatment groups CONSE and PSSE. However, for both fecal and litter, the PSSE treatment group tended (P ≤0.1) to have a lower Salmonella CFU/g compared to the CONSE treatment group. The results indicate that peanut skins may have potential application as an antimicrobial feed additive to reduce the transmission or proliferation of SE in poultry environments or flocks.

EU – Stable Campylobacter and Salmonella cases in the EU


The number of reported cases of illnesses caused by Campylobacter  and  Salmonella bacteria   in humans in Europe appear to level off over the past five years, according to the  latest zoonoses report released by the European Food Safety Authority (EFSA) and the European Center for Disease Prevention and Control (ECDC).

Campylobacteriosis, the most frequently reported gastrointestinal disease in the EU since 2005, affected more than 220,000 people in 2019. Salmonellosis was the second most frequently reported zoonosis in the EU, with around 88,000 people affected.

Of the 66,113 ready-to-eat food samples – foods that did not require cooking before consumption – 0.3% tested positive for  Salmonella . Of the 191,181 non-ready-to-eat food samples, 1.5% tested positive. 18 of the 26 Member States reporting on programs to control  Salmonella  in poultry populations met all their reduction targets, up from 14 in 2018.

The next most frequently reported diseases are   shiga-toxin-producing Escherichia coli (STEC), yersiniosis and listeriosis. The trend in confirmed human cases of listeriosis remained stable between 2015 and 2019, after a long period of increase. 2,621 cases were reported in 2019, mostly affecting individuals over the age of 64. It is the most serious disease, with high rates of hospitalization (92%) and mortality (17.6%).

The report also looks at the cause of outbreaks of foodborne illness in the EU, i.e. outbreaks in which two or more people contract the same disease after consuming the same contaminated food. Salmonella  remains the most frequently detected agent and causes 926 outbreaks; the number of outbreaks due to  S . Enteritidis  , on the other hand, has declined. The most common sources of outbreaks of salmonellosis were eggs and egg products. Noroviruses in fish and fishery products cause the greatest number of outbreaks (145) with “strong evidence” involving a food source.

A total of 5,175 outbreaks of foodborne illness were reported in 2019, a decrease of 12.3% from 2018.

The report also contains data on  Mycobacterium bovis / caprae ,  Brucella ,  Yersinia ,  Trichinella ,  Echinococcus ,  Toxoplasma  gondii , rabies, Q fever, West Nile virus and tularemia.

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Research – Persistence of Leptospira borgpetersenii Serovar Hardjo in Refrigerated Raw Milk: A Transmission Risk of Leptospirosis to Humans


Leptospira borgpetersenii serovar Hardjo (LH) is an important infectious agent of reproduction pathologies and lactation decline in cattle, with a possible zoonotic role. To figure out the potential zoonotic risk for human raw-milk consumption, the present study aims at assessing the persistence and viability of LH in refrigerated raw milk over a 10-day period, which is set as the maximum time range for raw-milk domestic consumption. A negative sample of fresh raw milk was contaminated with an LH strain (2 × 108 Leptospires/mL) and analyzed by a rrs (16S) gene targeting real-time PCR (rPCR) protocol for LH DNA at days 1, 2, 3, 6, 7, 9, and 10. Seven aliquots of the same sampling time were inoculated into a semisolid EMJH media for bacterial culture. All aliquots tested positive in both rPCR and culture, which demonstrates that raw milk does not alter the detectability and viability of LH, respectively. The analytical sensitivity (LoD, limit of detection) determined for the rPCR (103 Leptospires/mL) was repeatable during the study, whereas it gradually decreased when it came to the bacterial culture. This study demonstrates that bovine raw milk might be a potential vehicle of infection by LH, even when storage conditions are strictly respected. View Full-Text