Assessment of the remineralisation induced by contemporary ion-releasing materials in mineral-depleted dentine.

OBJECTIVES: Evaluate the ability of current ion-releasing materials to remineralise bacteria-driven artificial caries lesions. MATERIALS AND METHODS: Standardised class I cavities were obtained in 60 extracted human molars. Specimens underwent a microbiological cariogenic protocol (28 days) to generate artificial caries lesions and then were randomly divided into four restorative groups: adhesive + composite (negative control); glass ionomer cement (GIC); calcium silicate cement (MTA); and resin-modified calcium silicate cement (RMTA). Microhardness analysis (ΔKHN) was performed on 40 specimens (10/group, t = 30 days, 45 days, 60 days in artificial saliva, AS). Micro-CT scans were acquired (3/group, t = 0 days, 30 days, and 90 days in AS). Confocal microscopy was employed for interfacial ultra-morphology analysis (2/group, t = 0 days and 60 days in AS). Additional specimens were prepared and processed for scanning electron microscopy (SEM) and FTIR (n = 3/group + control) to analyse the ability of the tested materials to induce apatite formation on totally demineralised dentine discs (60 days in AS). Statistical analyses were performed with a significance level of 5%. RESULTS: Adhesive + composite specimens showed the lowest ΔKHN values and the presence of gaps at the interface when assessed through micro-CT even after storage in AS. Conversely, all the tested ion-releasing materials presented an increase in ΔKHN after storage (p < 0.05), while MTA best reduced the demineralised artificial carious lesions gap at the interface. MTA and RMTA also showed apatite deposition on totally demineralised dentine surfaces (SEM and FTIR). CONCLUSIONS: All tested ion-releasing materials expressed mineral precipitation in demineralised dentine. Additionally, calcium silicate-based materials induced apatite precipitation and hardness recovery of artificial carious dentine lesions over time. CLINICAL RELEVANCE: Current ion-releasing materials can induce remineralisation of carious dentine. MTA shows enhanced ability of nucleation/precipitation of hydroxyapatite compared to RMTA and GIC, which may be more appropriate to recover severe mineral-depleted dentine.

Hepatitis E and pregnancy: current state.

Hepatitis E virus (HEV) is responsible for more than 50% of acute viral hepatitis cases in endemic countries. Approximately 2 billion individuals live in hepatitis E-endemic areas and, therefore, are at risk of infection. According to World Health Organization, HEV causes about 20.1 million infections and 70 000 deaths every year. In developing countries with poor sanitation, this disease is transmitted through contaminated water and is associated with large outbreaks, affecting hundreds or thousands of people. In developed countries, autochthonous cases of HEV have been increasingly recognized in the past several years. Hepatitis E virus typically causes an acute, self-limiting illness similar to other acute viral hepatitis, such as hepatitis A or B, with about 0.2% to 1% mortality rate in the general population. However, the course of hepatitis E in pregnancy is different than the mild self-constraining infection described in other populations. During pregnancy, HEV infection can take a fulminant course, resulting in fulminant hepatic failure, membrane rupture, spontaneous abortions, and stillbirths. Studies from various developing countries have shown a high incidence of HEV infection in pregnancy with a significant proportion of pregnant women progressing to fulminant hepatitis with a fatality rate of up to 30%. The present review will highlight new aspects of the HEV infection and pregnancy.

Microbiological diagnosis of human papilloma virus infection. / Diagnóstico microbiológico de la infección por virus del papiloma humano.

Infection with human papillomavirus (HPV) is the leading cause of sexually transmitted infection worldwide. This virus generally causes benign lesions, such as genital warts, but persistent infection may lead to cervical cancer, anal cancer, vaginal cancer, and oropharyngeal cancer, although less frequently. Cervical cancer is a severe disease with a high mortality in some countries. Screening with cytology has been very successful in the last few years, but nowadays there are numerous studies that confirm that cytology should be replaced with the detection of HPV as a first line test in population based screening. There are several commercially available FDA approved tests for screening of cervical cancer. A new strategy, based on individual detection of the high risk genotypes HPV16 and HPV18, present in 70% of cervical cancer biopsies, has been proposed by some experts, and is going to be implemented in most countries in the future.

Hepatitis E seroprevalence in inflammatory bowel disease.

BACKGROUND AND AIMS: Several cases of chronic infection by hepatitis E virus (HEV) in immunocompromised patients have been described recently. Patients with inflammatory bowel disease (IBD) are frequently immunocompromised because of the disease itself or due to therapy. Our aims were to determine HEV seroprevalence in patients with IBD and to detect possible chronic forms. METHODS: We prospectively selected a random sample of 87 patients from our local IBD clinic database at the Gastroenterology Service, Hospital Ramón y Cajal, in Madrid, Spain. Patients completed an oral epidemiologic interview. Anti-HEV IgG and IgM antibodies and HEV-RNA were determined. Medical records were reviewed, focusing on drug exposure. RESULTS: We included 87 patients, with a mean age of 44.7 years (SD 16) and a mean of 10.4 years (SD 8.4) with IBD. Fifty-seven percent were diagnosed with Crohn's disease, 41.4% with ulcerative colitis and 1.1% with unclassified IBD. A total of 41.4% had received systemic glucocorticoids for more than 3 months, 32.2% had been treated with thiopurines, 16.1% with biological drugs, and 3.4% with methotrexate. Anti HEV-IgM was determined in 75 patients and IgG in 80, and were positive in 2.7% and 1.3%, respectively. HEV-RNA was analyzed in a random subset of 46 patients, and all determinations were negative. Therefore, no case of chronic HEV infection was detected. CONCLUSIONS: We found a low HEV seroprevalence of just 1.14% in patients with IBD, similar to that in the general population. This could be due to the lower degree of immunosuppression in this group, or to different dietary habits.

Patients infected with HIV are at high-risk for hepatitis E virus infection in Spain.

Hepatitis E virus is responsible for sporadic cases of acute, self-limited viral hepatitis not only in endemic but also in industrialized countries. In addition, some reports confirm that it can cause chronic infection and even cirrhosis in immunosuppressed and also in patients infected with HIV. There are few data about prevalence and incidence of HEV chronic infection in HIV-HEV coinfected individuals in Spain. The aim of this study is to investigate the prevalence of anti-HEV IgG in a representative sample of 448 patients infected with HIV and determine the role of age, gender, and CD4 counts in the detection of anti-HEV IgG antibodies in blood. In addition, the clinical features and ALT levels in relation to the presence of anti-HEV IgM and/or HEV-RNA in the blood of these patients were investigated. Anti-HEV IgG antibodies were detected in serum using a commercial enzyme immunoassay. All positive samples were studied further for the presence of anti-HEV IgM antibodies. In addition, HEV RNA was amplified by reverse transcriptase (RT)-nested PCR in all serum samples with IgM anti-HEV. The overall prevalence of anti-HEV IgG was 10.4% (45/448, 95% C.I. 7.2-12.8%). HEV-RNA was found in only one patient out of the 45 anti-HEV IgG positive samples studied. Regarding to gender and CD4 count, no difference in seroprevalence could be observed. This prevalence data suggest that patients infected with HIV can be considered a risk group for HEV infection and that chronic coinfection HEV-HIV seems to be a very rare event.

Hepatitis E: current status.

Acute hepatitis E is a very common disease in developing countries, to the point that, according to World Health Organization estimates, one third of the world's population has been exposed to HEV. It also causes outbreaks in refugee camps or after natural disasters such as floods or earthquakes. Sporadic cases of acute hepatitis have been observed in practically all European countries and other developed geographical areas, not only in travelers from endemic countries but also in people with no risk factors. But, lately, new aspects of this infection are appearing in industrialized countries such as the possibility of the disease becoming chronic in transplant patients, the immunocompromised in general, and even in patients with previous liver disease who are immunocompetent. In this comprehensive review, we summarize the current knowledge on HEV infection.

Swine farm environmental microbiome: exploring microbial ecology and functionality across farms with high and low sanitary status.

Introduction: Stringent regulations in pig farming, such as antibiotic control and the ban on certain additives and disinfectants, complicate disease control efforts. Despite the evolution of microbial communities inside the house environment, they maintain stability over the years, exhibiting characteristics specific to each type of production and, in some cases, unique to a particular company or farm production type. In addition, some infectious diseases are recurrent in specific farms, while other farms never present these diseases, suggesting a connection between the presence of these microorganisms in animals or their environment. Therefore, the aim of this study was to characterise environmental microbiomes of farms with high and low sanitary status, establishing the relationships between both, health status, environmental microbial ecology and its functionality. Methods: For this purpose, 6 pig farms were environmentally sampled. Farms were affiliated with a production company that handle the majority of the pigs slaughtered in Spain. This study investigated the relationship among high health and low health status farms using high throughput 16S rRNA gene sequencing. In addition, to identify ecologically relevant functions and potential pathogens based on the 16S rRNA gene sequences obtained, functional Annotation with PROkaryotic TAXa (FAPROTAX) was performed. Results and Discussion: This study reveals notable differences in microbial communities between farms with persistent health issues and those with good health outcomes, suggesting a need for protocols tailored to address specific challenges. The variation in microbial populations among farms underscores the need for specific and eco-friendly cleaning and disinfection protocols. These measures are key to enhancing the sustainability of livestock farming, ensuring safer products and boosting competitive edge in the market.

[Acute, chronic and fulminant hepatitisE: seven years of experience (2004-2011)]. / Hepatitis agudas, crónicas y fulminantes por virus de la hepatitisE: 7años de experiencia (2004-2011).

OBJECTIVE: To study the clinical and epidemiological profiles of in 43cases of acute hepatitis, 5cases of fulminant hepatitis, and one of chronic hepatitis due to hepatitis E virus (HEV), detected over a 7-year period. PATIENTS: Forty-nine individuals (33male and 10female) treated between 2004 and 2011 in the Hospital Ramón y Cajal (Comunidad de Madrid, Spain). The diagnosis was made by the detection of IgG and IgM anti-HEV and RNA HEV in serum samples. Acute hepatitisE was defined by the presence of IgM anti-HEV and/or RNA HEV in serum, and chronic hepatitisE if the ARN was detectable more than 6months. Fulminant hepatitisE was diagnosed if encephalopathy was observed in addition to IgM anti-HEV and/or RNA HEV in serum. RESULTS: The median age was 46.67 and 49.6years in acute hepatitisE and fulminant hepatitisE, respectively. The risk factors recorded were travel to endemic areas in 13patients, 4were in contact with animals, 4suffered from hepatic steatosis due to alcohol consumption, 3consumed uncontrolled foods, and 2drank water from streams. DISCUSSION: HEV is the cause of acute self-limited hepatitis, although 36.73% of the studied cases had to be hospitalised. However a small number of patients, 10.2%, had fulminant hepatitis requiring liver transplant. Chronic hepatitisE is very infrequent in immunocompetent individuals. The increase in incidence of hepatitisE is due to the introduction of better diagnostic tests in recent years.

Computer-aided drug repurposing to tackle antibiotic resistance based on topological data analysis.

The progressive emergence of antimicrobial resistance has become a global health problem in need of rapid solution. Research into new antimicrobial drugs is imperative. Drug repositioning, together with computational mathematical prediction models, could be a fast and efficient method of searching for new antibiotics. The aim of this study was to identify compounds with potential antimicrobial capacity against Escherichia coli from US Food and Drug Administration-approved drugs, and the similarity between known drug targets and E. coli proteins using a topological structure-activity data analysis model. This model has been shown to identify molecules with known antibiotic capacity, such as carbapenems and cephalosporins, as well as new molecules that could act as antimicrobials. Topological similarities were also found between E. coli proteins and proteins from different bacterial species such as Mycobacterium tuberculosis, Pseudomonas aeruginosa and Salmonella Typhimurium, which could imply that the selected molecules have a broader spectrum than expected. These molecules include antitumor drugs, antihistamines, lipid-lowering agents, hypoglycemic agents, antidepressants, nucleotides, and nucleosides, among others. The results presented in this study prove the ability of computational mathematical prediction models to predict molecules with potential antimicrobial capacity and/or possible new pharmacological targets of interest in the design of new antibiotics and in the better understanding of antimicrobial resistance.

Development of a specific polymerase chain reaction assay for the detection of Basidiobolus.

The etiology of chronic diarrhea is complex in humans and animals. It is always necessary to evaluate a list of differential diagnosis, including bacteria, protozoa and fungi. Basidiobolomycosis is a fungal disease reported sporadically worldwide, mainly caused by B. ranarum, a frequent organism found in soil or in the intestine and skin of lizards and frogs. It is an opportunistic pathogen that causes infections characterized by granulomatous lesions in the subcutaneous tissues as well as in the intestinal wall in humans and animals. In this work we have developed a PCR technique to differentiate Basidiobolus from other causes of intestinal disease in dogs and humans. To test the specificity of the PCR assay we included closely related organisms, common intestinal microbiota and pathogenic organisms, such as Aspergillus, Candida, Cryptosporidium, Escherichia, Giardia, Mucor, Proteus, Rhizopus and Salmonella. Pythium insidiosum, which cause clinically similar disease in dogs but require a different treatment. Only Basidiobolus was positive to the PCR assay.

Severe Acute Hepatitis of Unknown Origin in Children: What Do We Know Today?

In May 2022, the UK International Health Regulations National Focal Point notified World Health Organization of 176 cases of severe acute hepatitis of unknown etiology in children under 10 years of age. From that moment on, cases of severe acute hepatitis of unknown origin in children began to be reported in several countries. As of June 17, 2022, a total of 991 cases had been reported in 35 countries worldwide, 50 children needed a liver transplant and 28 patients died. According to information published by ECDC, 449 cases have been detected in 21 EU countries. The children were between 1 month and 16 years of age. Adenovirus was detected in 62.2% of the analyzed samples. So far, the cause of these cases is unknown and many hypotheses remain open, but hepatitis A-E viruses and COVID-19 vaccines have been ruled out. A possible hypothesis has been published to explain the cause of these cases of severe hepatitis, according to which it could be a consequence of adenovirus infection in the intestine in healthy children previously infected with SARS-CoV-2. No other clear epidemiological risk factors have been identified to date. Thus, at this time, the etiology of the current cases of hepatitis remains under active investigation.

Antibiotic resistant bacteria: current situation and treatment options to accelerate the development of a new antimicrobial arsenal.

INTRODUCTION: Antibiotic resistance is one of the biggest public health threats worldwide. Currently, antibiotic-resistant bacteria kill 700,000 people every year. These data represent the near future in which we find ourselves, a 'post-antibiotic era' where the identification and development of new treatments are key. This review is focused on the current and emerging antimicrobial therapies which can solve this global threat. AREAS COVERED: Through a literature search using databases such as Medline and Web of Science, and search engines such as Google Scholar, different antimicrobial therapies were analyzed, including pathogen-oriented therapy, phagotherapy, microbiota and antivirulent therapy. Additionally, the development pathways of new antibiotics were described, emphasizing on the potential advantages that the combination of a drug repurposing strategy with the application of mathematical prediction models could bring to solve the problem of AMRs. EXPERT OPINION: This review offers several starting points to solve a single problem: reducing the number of AMR. The data suggest that the strategies described could provide many benefits to improve antimicrobial treatments. However, the development of new antimicrobials remains necessary. Drug repurposing, with the application of mathematical prediction models, is considered to be of interest due to its rapid and effective potential to increase the current therapeutic arsenal.

Antibiotic resistance is currently one of the biggest public health threats worldwide. Right now, antibiotic-resistant bacteria kill 700,000 people every year. Many of the available antibiotics are useless against drug resistant bacteria. The present and near future in which we find ourselves is a post-antibiotic era, where the antibiotics we have are unable to combat the bacterial infections that are emerging. In this review, published studies were accessed to explore different techniques that are available to improve existing treatment options. Currently, these strategies cannot replace antibiotic therapy. The reviewed knowledge presents these alternatives as adjuvants to antibiotic treatments. Therefore, research into new antibiotics remains important. This review exposes that the repurposing of known drugs as antibiotics could contribute to the cost-effective search of new antibiotics in a faster and cost-effective way compared to traditional development methods of new antibiotics. The review emphasizes the urgency of identifying new pharmacological targets that can aid in the development of new therapies, and to improve known alternative therapies. Drug repurposing can greatly shorten the time and cost of development of new antibiotics. This strategy adds to the value of certain commercialized molecules, recovering part of the investment made by the pharmaceutic industry. In addition, it provides greater knowledge about other alternative antibiotic therapies and about the mechanisms by which bacteria develop antibiotic resistance.

Evaluation of knowledge about antibiotics and engagement with a research experience on antimicrobial resistance between pre-university and university students for five school years (2017-2021).

Antimicrobial resistance (AMR) remains a serious global health problem. Spain is the fifth country in Europe with the highest consumption of antibiotics, due in part to ignorance of the good use of these drugs and the problem of AMR. To avoid a post-antibiotic era, adequate training on this problem is key to create social awareness. This study aimed to evaluate the impact that the SWICEU project, an academic program about antibiotic discovery, has had on the knowledge of AMR and rational use of antimicrobials in pre-university students from seven schools in the province of Valencia during five academic years (2017-2021), as well as to evaluate the level of satisfaction of university and pre-university students who have participated in the project. For this study, a survey was carried out with multiple-choice questions with a single correct answer to evaluate the knowledge acquired by pre-university students before and after the project. A satisfaction survey was also designed with a Likert scale from the lowest to the highest level of satisfaction for the two groups of students after the project. Data on knowledge surveys indicated an increase in the mean number of correct answers after the sessions. In satisfaction surveys, we highlighted the issue that referred to the project's recommendation. The data obtained confirm this project as a valuable activity, as it allows learning about AMR and the rational use of antibiotics in a pleasing and attractive way for young pre-university and university students.

Innovative gamification and outreach tools to raise awareness about antimicrobial resistance.

Since 2017, the SWICEU team has developed various informative actions and innovative gamification supports to educate and raise awareness about antimicrobial resistance (AMR) and the correct use of antibiotics among the general population especially among young people. This case study presents the results obtained in the last 5 years with the strategies carried out by this team, composed of students and professors of Health Sciences, Industrial Design Engineering, and Communication Sciences at CEU Cardenal Herrera University (CEU UCH) in Valencia (Spain). Over the past 5 years, playful educational supports have been developed to make the health problem of bacterial resistance and the action of antibiotics more understandable among young people. The dissemination media used, with the same objective of teaching and raising awareness about AMR in a creative and innovative way, have been selected according to the trends in digital communication and use of scientific and health content provided by the most recent studies carried out among the Spanish population. These strategies have included decalogues or "tips" with useful advice, infographics, YouTube videos, Twitter threads, online challenges on Kahoot, stories on Instagram, use of QR codes, etc. These actions have also obtained diffusion in the media and have been awarded by different national and international entities. The good results obtained in the case under study allow us to establish recommendations for the design of innovative educational gamification and dissemination supports on AMR, especially aimed at younger audiences.

Synthesis of Quinolones and Zwitterionic Quinolonate Derivatives with Broad-Spectrum Antibiotic Activity.

Quinolones are one of the most extensively used therapeutic families of antibiotics. However, the increase in antibiotic-resistant bacteria has rendered many of the available compounds useless. After applying our prediction model of activity against E. coli to a library of 1000 quinolones, two quinolones were selected to be synthesized. Additionally, a series of zwitterionic quinolonates were also synthesized. Quinolones and zwitterionic quinolonates were obtained by coupling the corresponding amine with reagent 1 in acetonitrile. Antibacterial activity was assessed using a microdilution method. All the compounds presented antibacterial activity, especially quinolones 2 and 3, selected by the prediction model, which had broad-spectrum activity. Furthermore, a new type of zwitterionic quinolonate with antibacterial activity was found. These compounds can lead to a new line of antimicrobials, as the structures, and, therefore, their properties, are easily adjustable in the amine in position 4 of the pyridine ring.

Antibiotic removal does not affect cecal microbiota balance and productive parameters in LP robust rabbit line.

Antimicrobial resistance is an important threat to public health worldwide, being one of the main death causes in 2050. Moreover, global health is currently underpinned by the "One Health" concept, whereby livestock is strictly related to human and environmental health. However, in the case of the meat rabbit industry, antibiotic additives are still added to prevent gastrointestinal diseases. Current food and consumer awareness require the implementation of sustainable production systems, where robustness and resilience are increasingly important. Hence, the aim of this study was to evaluate the effect of antibiotic feed supplementation on microbiota, and productive performance during the rabbit growing period in a robust genetic line. For this purpose, a total of 432 weaned rabbits were randomly housed, cecum samples were taken on the weaning day and at the end of the growing period (28 and 61 days of age, respectively), and 16S rRNA sequencing analysis was performed. Results showed a higher microbiota complexity at the end of growing in both experimental groups. Firmicutes represented the dominant phylum of the cecal community, followed by Bacteroidota in both groups. Moreover, Victivallis and Escherichia-Shigella genera were only identified in the experimental group without antibiotic supplementation at the end of the growing period. In conclusion, antibiotic feed supplementation had no effect on microbiota composition and productive performance in the robust genetic line reared. These results evidence the importance of the development of rabbit robust genetic lines as an alternative tool to antibiotic administration in epizootic enteropathy control.

Commensal Escherichia coli Antimicrobial Resistance and Multidrug-Resistance Dynamics during Broiler Growing Period: Commercial vs. Improved Farm Conditions.

New measures applied to reduce antimicrobial resistances (AMR) at field level in broiler production are focused on improving animals' welfare and resilience. However, it is necessary to have better knowledge of AMR epidemiology. Thus, the aim of this study was to evaluate AMR and multidrug resistance (MDR) dynamics during the rearing of broilers under commercial (33 kg/m2 density and max. 20 ppm ammonia) and improved (17 kg/m2 density and max. 10 ppm ammonia) farm conditions. Day-old chicks were housed in two poultry houses (commercial vs. improved), and no antimicrobial agents were administered at any point. Animals were sampled at arrival day, mid-period and at slaughter day. High AMR rates were observed throughout rearing. No statistical differences were observed between groups. Moreover, both groups presented high MDR at slaughter day. These results could be explained by vertical or horizontal resistance acquisition. In conclusion, AMR and MDR are present throughout rearing. Moreover, although a lower level of MDR was observed at mid-period in animals reared under less intensive conditions, no differences were found at the end. In order to reduce the presence of AMR bacteria in poultry, further studies are needed to better understand AMR acquisition and prevalence in differing broiler growing conditions.

Assessment of Microbiota Modulation in Poultry to Combat Infectious Diseases.

Poultry is one of the main agricultural sub-sectors worldwide. However, public concern regarding animal welfare and antimicrobial resistance has risen in recent years. Due to the influence of management practices on microbiota, it might be considered to evaluate poultry welfare and health. Therefore, the objective of this research was to analyse the influence on microbiota balance of broilers under commercial and optimal farm conditions, using 16S rRNA sequencing analysis. The research was performed in two identical poultry houses (commercial vs. optimal). Results showed a higher level of microbiota complexity in the group reared under optimal farm conditions at the end of rearing. Regarding microbiota composition, Firmicutes was the dominant phylum during the entire growing period. However, the second most prevalent phylum was Proteobacteria at the arrival day, and Bacteroidetes from the mid-period onward in both groups. Moreover, the most predominant genera identified were Oscillospira, Ruminococcus, Bacteroides, and Coprococcus. In conclusion, it is necessary to optimize farm management as much as possible. Using gut microbiota diversity and composition as biomarkers of animal health could be an important tool for infectious disease control, with the aim of reducing the administration of antibiotics at field level.

Low prevalence of hepatitis E infection among pregnant women in Madrid, Spain.

Hepatitis E virus, a cause of sporadic hepatitis in developed countries is present in Spain. The aims of this study were to determine whether the prevalence of IgG anti-hepatitis E virus antibodies has increased in recent years in Spain and the prevalence in a study population at risk of developing the disease following the infection. Serum samples from 1,040 women in the first trimester of pregnancy were studied. The prevalence rate of 3.6% has not increased significantly since 1999 in spite of the large number of immigrants from endemic regions. IgM anti-HEV antibodies were detected in 0.67% of the patients suggesting that although subclinical infection exists the prevalence is very low. The reasons for the differences in the morbidity of HEV in pregnant women in different geographical areas remain unclear. Good hygienic measures and public health conditions are important factors for ensuring low prevalence of hepatitis E in Spain.

[Prevalence of hepatitis E virus (HEV) and risk factors in pig workers and blood donors]. / Prevalencia del virus de la hepatitis E (VHE) y factores de riesgo en trabajadores de explotaciones porcinas y donantes voluntarios.

INTRODUCTION: Hepatitis E virus (HEV) is the main causative agent of enterically transmitted non-A non-B hepatitis with a self-limiting clinical presentation in humans. The increasing number of non-immigrant cases of hepatitis E and the high prevalence detected in pigs suggested that this species is a reservoir. Several studies have been published describing differences in the prevalence of anti-HEV antibodies between people exposed and not exposed to pigs, but the risk factors for the acquisition of the virus have not been well studied. The aim of this work was to study the prevalence of hepatitis E virus (HEV), IgG and IgM antibodies anti-HEV and the risk factors for the acquisition of this virus in a populations exposed and unexposed to pigs. METHODS: Sera from 212 people were tested for the presence of RNA-HEV, IgG and IgM antibodies anti-HEV. Positive results obtained using ELISA assays were confirmed by western-blot. RESULTS: RNA-HEV and IgM anti-VHE were not detected in any of the individuals. Twenty-five samples (11.8%) showed IgG anti-HEV, 21 (18.6%) persons in contact with pigs and 4 (4%) unexposed individuals (P=0.004); 19 (12.8%) had travelled out of Spain in the last year (P=0.507). None of the 25 seropositive people had consumed raw shellfish (P=0.999), whereas 23 (12.6%) had consumed raw vegetables (P=0.387) and 12 (30%) usually drank untreated water (P=0.008). CONCLUSION: These data support that HEV infection should be treated as an occupational disease illness in pig workers. Therefore, systematic application of hygiene measures in this group is highly recommended to avoid exposure to this virus.