National taxation on sugar-sweetened beverages and its association with overweight, obesity, and diabetes.

BACKGROUND: Consumption of sugar-sweetened beverages (SSBs) has been linked to several adverse health outcomes, thus many countries introduced taxation to reduce it. OBJECTIVES: To summarize national SSB taxation laws and to assess their association with obesity, overweight and diabetes. METHODS: We conducted a systematic scoping review up to January 2022 on PubMed, Web of Science, Embase, and Google Search to identify taxes on SSBs. An interrupted time series analysis (ITSA) was conducted on 17 countries with taxation implemented in 2013 or before to evaluate the level and slope modifications in the rate of change of standardized prevalence rates of overweight, obesity, and diabetes. Random-effects meta-regression was used to assess whether year of entry into force of the law, national income, and tax design affected observed results. RESULTS: We included 76 tax laws issued between 1940 and 2020 by 43 countries, which were heterogeneous in terms of tax design, amount, and taxed products. Among children and adolescents, ITSA showed level or slope reduction for prevalence of overweight and obesity in 5 (Brazil, Samoa, Palau, Panama, Tonga) and 6 (El Salvador, Uruguay, Nauru, Norway, Palau, Tonga) countries out of 17, respectively. No clear pattern of modification of results according to investigated factors emerged from the meta-regression analysis. CONCLUSIONS: Taxation is highly heterogeneous across countries in terms of products and design, which might influence its effectiveness. Our findings provide some evidence regarding a deceleration of the increasing prevalence rates of overweight and obesity among children occurring in some countries following introduction of taxation. PROSPERO registration number: CRD42021233309.

Use of oxygen-ozone therapy to improve the effectiveness of antibiotic treatment on infected arthroplasty: protocol for a superiority, open-label, multicentre, randomised, parallel trial.

INTRODUCTION: Surgical site infections still remain a major public health challenge and have become an increasing universal risk, especially for the implantation of orthopaedic devices.Unfortunately, the discovery and increasingly widespread use (especially the misuse) of antibiotics have led to the rapid appearance of antibiotic-resistant strains today; more and more infections are caused by microorganisms that fail to respond to conventional treatments.Oxygen-ozone therapy has been extensively used and studied for decades across various potential medical applications and has provided consistent effects with minimal side effects.This study aims to determine the superiority of oxygen-ozone therapy in combination with oral antibiotic therapy in patients with wound infections after an orthopaedic device implantation when compared with antibiotic therapy alone. METHODS AND ANALYSIS: This is an open-label, multicentre, randomised, parallel-group study that aims to assess the efficacy and safety of oxygen-ozone therapy in combination with oral antibiotic therapy to treat infections in patients (male or female aged ≥18 years) having undergone surgery for the implant of an orthopaedic device. Patients must have at least one (but no more than three) postoperative wounds in the site of surgery (ulcers, eschars and sores) and at least one symptom (pain, burning, redness and malodour) and at least one sign (erythema, local warmth, swelling and purulent secretion) of infection of at least moderate intensity (score ≥2) in the target lesion at the screening visit (patients with wounds without signs of localised infection or with undermining wounds will be excluded).Patients (n=186) will be recruited from five Italian hospitals and studied for 7 weeks. All will be assigned to one of the two treatment groups according to a web-based, centralised randomisation procedure and placed into either the (1) intervention: oxygen-ozone therapy 2-3 times a week for 6 weeks (for a maximum of 15 sessions) simultaneously with an appropriate oral antibiotic therapy prescribed at baseline or (2) control: oral antibiotic therapy prescribed at baseline.The primary outcome is the efficacy and superiority of the treatment (ozone and oral antibiotic therapies); secondary outcomes include the resolution of signs and symptoms, modifications in lesion size and the treatment's safety and tolerability. ETHICS AND DISSEMINATION: This study has been reviewed and approved by the responsible Independent Ethics Committee (IEC) of COMITATO ETICO CAMPANIA NORD, located at 'Azienda Ospedaliera San Giuseppe Moscati di Avellino'.After completion of the study, the project coordinator will prepare a draft manuscript containing the final results of the study on the basis of the statistical analysis. The manuscript will be derived by the co-authors for comments, and after revision, it will be sent to a major scientific journal. Findings will be disseminated via online and print media, events and peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04787575.

Knowledge and beliefs about vaccination in pregnant women before and during the COVID-19 pandemic.

Introduction: Vaccine hesitancy threatens the health of populations and challenges Public Health professionals. Strategies to reduce it aim to improve people's risk perception about vaccine-preventable diseases, fill knowledge gaps about vaccines and increase trust in healthcare providers. During pregnancy, educational interventions can provide a proper knowledge about safety and efficacy of maternal and childhood vaccinations. Fighting hesitancy and clarifying doubts is fundamental during the COVID-19 pandemic, which may have affected people's knowledge and beliefs toward vaccination. This study aimed at assessing if the advent of the pandemic was associated with changes in pregnant women's knowledge and beliefs toward vaccination, and trust in healthcare services. Methods: A repeated cross-sectional study was conducted through self-reported questionnaires in a Roman teaching hospital, where educational classes about vaccinations are routinely held as part of a birthing preparation course. Data were collected on a sample of pregnant women before and during the pandemic. Free-of-charge flu vaccinations were offered to all course participants and adherence to flu vaccination was assessed. Results: The proportion of pregnant women reporting that vaccines have mild side effects and that are sufficiently tested increased from 78.6 to 92.0% (p = 0.001) and from 79.4 to 93.2% (p = 0.001), respectively. There was a reduction from 33.0 to 23.3% (p = 0.065) in the proportion of those declaring that healthcare workers (HCWs) give information only on the benefits and not on the risks of vaccines, and a reduction from 27.3 to 12.1% (p = 0.001) in those reporting that vaccines are an imposition and not a free choice of mothers. Trust in National Health Service (NHS) operators slightly decreased. Among participants, the monthly flu vaccination adherence ranged from 50.0% in November to 29.2% January for 2019-20 flu season, and from 56.3% in September to 14.5% in January for 2020-21 flu season, showing a higher vaccination acceptance in the earlier months of 2020-21 flu season. Conclusions: The pandemic may have positively affected pregnant women's knowledge and opinions about vaccinations and trust in HCWs, despite a possible negative impact on their perceptions about NHS operators. This should inspire Public Health professionals to rethink their role as health communicators.

Polygenic risk prediction models for colorectal cancer: a systematic review.

BACKGROUND: Risk prediction models incorporating single nucleotide polymorphisms (SNPs) could lead to individualized prevention of colorectal cancer (CRC). However, the added value of incorporating SNPs into models with only traditional risk factors is still not clear. Hence, our primary aim was to summarize literature on risk prediction models including genetic variants for CRC, while our secondary aim was to evaluate the improvement of discriminatory accuracy when adding SNPs to a prediction model with only traditional risk factors. METHODS: We conducted a systematic review on prediction models incorporating multiple SNPs for CRC risk prediction. We tested whether a significant trend in the increase of Area Under Curve (AUC) according to the number of SNPs could be observed, and estimated the correlation between AUC improvement and number of SNPs. We estimated pooled AUC improvement for SNP-enhanced models compared with non-SNP-enhanced models using random effects meta-analysis, and conducted meta-regression to investigate the association of specific factors with AUC improvement. RESULTS: We included 33 studies, 78.79% using genetic risk scores to combine genetic data. We found no significant trend in AUC improvement according to the number of SNPs (p for trend = 0.774), and no correlation between the number of SNPs and AUC improvement (p = 0.695). Pooled AUC improvement was 0.040 (95% CI: 0.035, 0.045), and the number of cases in the study and the AUC of the starting model were inversely associated with AUC improvement obtained when adding SNPs to a prediction model. In addition, models constructed in Asian individuals achieved better AUC improvement with the incorporation of SNPs compared with those developed among individuals of European ancestry. CONCLUSIONS: Though not conclusive, our results provide insights on factors influencing discriminatory accuracy of SNP-enhanced models. Genetic variants might be useful to inform stratified CRC screening in the future, but further research is needed.

Enhancement of Vaccination Attitude and Flu Vaccination Coverage among Pregnant Women Attending Birthing Preparation Course.

Most vaccinations are recommended within the 15th month of life, in order to reduce risks and to protect children from the initial stages of their lives. A vaccination training session was carried out during the birthing preparation course, aimed at increasing the attitude toward vaccination in maternal-child age. A questionnaire on vaccination awareness was administered before and after the training session and on-site flu vaccination was offered to women and their companions. The percentage of participants who consider the preparatory course a useful tool to obtain information about vaccines increases significantly from 30.34% at pre-intervention to 64.56% at post-intervention (p < 0.001). There is a significant increase in the mean number of vaccinations that the participants want their children to get. The number of participants believing that there is no relationship between vaccination and autism rose from 41.05 to 72.97% (p < 0.001). In total, 48 out of 119 (40.34%) pregnant women participating in the course and 39 companions were vaccinated for influenza. Vaccination knowledge and attitude significantly increased after a training session dedicated to vaccination as a part of the pregnant pre-birth course, whose aim can be therefore extended to the management of the health of the child, well beyond the period of pregnancy, according to the life-course approach to health.

[The assessment of the sanitation of surfaces and instruments in the context of hospital refection]. / Idoneità igienico-sanitaria delle superfici e degli strumenti nella ristorazione collettiva: analisi di un'esperienza nella realtà ospedaliera.

The Authors present the results of an experience carried out in a University General Hospital, for the assessment of the sanitation of surfaces and instruments in the context of hospital refection. A specific procedure has been quarterly implemented in order to verify the correct execution of the sanitization procedures. In the time-period September 2016 - March 2020 Petri dishes and tampons were used in order to determine the following microbiological parameters and indicators: total bacterial load at 30 degrees C, Coliforms, Listeria monocytogenes, Salmonella spp, Staphylococcus aureus, Escherichia coli and mycetic load. Only 7 out of 82 sanitized surfaces (8.5% of the total) were found to be not complying, only for total bacterial load at 30 degrees C, mycetic load and Coliforms. The systematic application of this procedure and the results of the survey conducted, comforting as a whole, confirm the attention reserved to the hygienic level of surfaces, tools, equipment and utensils, in the context of the centralized catering service of the hospital, in which the Health Department, sharing with the UOC Hospital Hygiene the specific hygienic procedure, has always been at the forefront of the proposal of interventions, considering the increased susceptibility and vulnerability of the hospitalized patients.

A management model for Hospital Hygiene Unit: evidence-based proactive surveillance of potential environmental sources of infection in order to prevent patient's risk.

INTRODUCTION: The aim of this study is to describe a proactive surveillance system of food, water and environmental surfaces, in order to avoid Healthcare-Associated Infections (HAIs) from hospital environment. METHODS: It is a retrospective descriptive study. The surveillance system consists of two integrated phases: pre-analytic and post-analytic. The activities are distinguished in ordinary control activities, performed after scheduled and shared surveys, and compliance activities, performed when it is necessary to establish the adequacy of the destination use, for example opening a new ward. RESULTS: A total of 1,470 Samples were collected and 539 Reports were generated across the five-year study period. Water for human consumption procedure: a statistically significant trend was found only in the total number of Samples collected (p < 0.001). Legionella spp. infection water risk procedure: all Samples and Reports, with the exception of Compliance Report Samples, showed a statistically significant trend (p < 0.001). Pseudomonas aeruginosa water risk procedure: only Ordinary Reports and Compliance Report Samples trend were statistically significant (p = 0.002 and p = 0.028 respectively). Effectiveness of surface sanitization procedure: no trend was statistically significant (p < 0.05). Hospital catering and food surfaces procedure: Samples and Reports yearly number was constant, no trend analysis was performed. HAIs prevalence was never over 5% in the hospital under study. CONCLUSIONS: This surveillance system of water, food and environmental surfaces represents an innovative way of approaching hospital safety for patients and personnel because it overcomes the limitations due to a classic approach limited to a laboratory analytic phase only, according to the best available scientific evidence.

[Hospital foodservice through the Cook Chill system: a two-year experience in a University teaching hospital, Italy]. / La ristorazione in ospedale mediante il sistema "Cook and Chill": un'esperienza di 2 anni in un Policlinico Universitario.

The Authors present their two-year experience regarding an evaluation of the hygienic quality of ready-to-eat foods in a hospital foodservice, both for patients' meals and hospital staff, prepared by using the Cook Chill system. According to the microbiological parameters provided by International Guidelines, 23 of 27 food samples that were collected and analyzed were found to be satisfactory, one was acceptable and only three were unsatisfactory (two for aerobic colony count and one both for aerobic colony count and hygienic procedure). Escherchia coli, Staphylococcus aureus, Salmonella, Listeria monocytogenes, and Clostridium perfringens were absent in all of the analyzed products, The study results are encouraging and confirm the need to always verify that the different phases of production of hospital meals are correctly implemented, even when the foodservice is out-sourced. This has always been considered a priority in the study hospital, where the Health Department is at the forefront both in control and verification of food safety practices and in offering training activities, especially in view of the increased susceptibility of hospitalized patients.

[Resident physicians' participation to the activities of the hospital hygiene unit in a teaching hospital: a pilot study]. / Partecipazione dei medici in formazione specialistica alle attività dell'unità operativa complessa "Igiene ospedaliera" in un policlinico universitario: studio pilota.

INTRODUCTION: The Hospital Hygiene Unit ensures hospital patient safety, through surveillance and control of environmental conditions of risk. In this context, resident physicians in Hygiene and Preventive Medicine of the Catholic University of the Sacred Heart (UCSC) are required to attend the unit to acquire professional skills, for two months (four weeks in the first year of residency and four weeks in the second year). In the initial phase of the rotation, residents are acquainted with the organization and assigned activities. Ongoing meetings with the tutor take place to verify the progress of activities in which they are involved; verification of acquired skills is performed at the end of the period of attendance. The aim of the study was to evaluate resident doctors' opinions about their training experience, in order to assess the perceived quality and pursue continuous improvement of the training program. MATERIALS AND METHODS: A questionnaire was administered to resident physicians attending the first three years of residency; the survey consisted of 11 multiple choice questions on organization, attendance, training and overall satisfaction and 3 open-ended questions on strengths, weaknesses and proposals for improvement. RESULTS: Fourteen of 15 residents (93.3%) completed the questionnaire: seven were male, five were first-year residents, five were second-year and four were third-year residents. Overall, 78% gave a positive assessment of the quality of training; in particular, 11 of 14 residents reported that the experience was very relevant to their training in Hygiene and Preventive Medicine. Responses regarding the training organization were also mostly positive (75%), as were those regarding attendance (57%) and overall satisfaction (67%). Fifty percent reported difficulties in combining this internship with the other activities planned with their tutor. CONCLUSIONS: Positive opinions prevail in all areas of assessment, although there are some aspects that can be improved, including the possibility to extend the period of attendance. Overall, training activities at the Operative Unit of Hospital Hygiene are appreciated by resident physicians, who consider them an important opportunity for professional growth.

[Hygienic safety of infant milk powder formulas in hospital setting]. / La sicurezza igienica del latte in polvere per la prima infanzia nella realtà ospedaliera.

The authors present the results of a study whose aim was to assess the hygienic quality of powder and reconstituted milk for early childhood, in a University General Hospital in Rome, Italy. This procedure is an integral part of the systematic verification activities that the hospital Health Management department considers as a priority for patient safety. The absence of contamination in all tested samples confirms the suitability of adopted procedures to ensure a safe product, considering the increased vulnerability of newborns, especially if preterm.

[Hygienic suitability of food and food-contact surfaces in a hospital canteen: the experience of a University Hospital in Italy]. / Idoneità igienico-sanitaria di alimenti e superfici in una mensa ospedaliera: un'esperienza in un Policlinico Universitario.

The Authors present the results of a study performed during a time-period of two years, to evaluate the hygienic quality of ready-to-eat foods, prepared and served in a hospital catering service, and the microbiological status of food-contact surfaces. Food hygiene was evaluated using non-pathogenic indicator microorganisms. The study was part of the verification activities that the hospital Health Department considers as a priority in order to guarantee patient safety. Only one of 52 food samples tested was considered unsatisfactory; the examined surfaces were not fully satisfactory in one of four cases. The study results, although encouraging as a whole, especially with respect to the hygienic safety of food prepared and served in the hospital, confirm the need to continuously verify that the appropriate environmental sanitation procedures are applied, even in the case of outsourcing. Considering the increased susceptibility of hospitalized patients, this remains a priority in the hospital where the study was performed.

[Street food safety in Rome, Italy]. / La sicurezza alimentare nello "street food": un'esperienza nella città di Roma.

The Authors describe the results of inspections carried out in 22 street food outlets in the city of Rome, Italy, from 7 April to 28 May 2014. In general, structural requirements of outlets were met but some critical aspects related to hygiene, in particular of instruments, surfaces and worktops, were identified. Results suggest the need to ensure compliance with sanitation requirements of this particular type of food outlet, in order to ensure food safety and, consequently, consumers' health.

Extracorporeal Photopheresis for Second-Line Treatment of Chronic Graft-versus-Host Diseases: Results from a Health Technology Assessment in Italy.

OBJECTIVES: To develop a comparative, cost-effectiveness, and budget impact analysis of Therakos online extracorporeal photopheresis (ECP) compared with the main alternatives used for the treatment of steroid-refractory/resistant chronic graft-versus-host disease (cGvHD) in Italy. METHODS: The current therapeutic pathway was identified by searching medical databases and from the results of a survey of practice in Italian clinical reference centers. A systematic review was performed to evaluate the efficacy and safety of second-line alternatives. Budget impact and cost-effectiveness analyses were performed from the Italian National Health Service perspective over a 7-year time horizon through the adaption of a Markov model. The following health states were considered: complete and partial response, stable disease, and progression. A discount rate of 3% was applied to costs and outcomes. RESULTS: The most common alternatives used in Italy for the management of steroid-refractory/resistant cGvHD were ECP, mycophenolate, pentostatin, and imatinib. The literature review highlighted that complete and partial responses are higher with ECP than with the alternatives while serious adverse events are less common. The economic analysis showed that Therakos online ECP represents the dominating alternative, in that it delivers greater benefit at a lower cost. In fact, according to the alternatives considered, cost saving ranged from €3237.09 to €19,903.51 per patient with 0.04 to 0.21 quality-adjusted life-year gained. CONCLUSIONS: Therakos online ECP should be considered an effective, safe, and cost-effective alternative in steroid-refractory/resistant cGvHD. There is inequality in access, and a dedicated reimbursement tariff, however, should be introduced to overcome these barriers.

[Vocational training in public health during medical school: a pilot study]. / Tirocinio professionalizzante in Sanità Pubblica nel Corso di Laurea in Medicina e Chirurgia. Un'esperienza pilota.

UNLABELLED: The need to integrate clinical and public health training of medical students is increasingly important. Future physicians need to be able to deal with new, complex and growing public health challenges. MATERIALS AND METHODS: A literature search was performed through Pubmed to identify the conceptual reference framework. Meetings were carried out to identify the most appropriate modalities and priorities required for drafting the project, to identify the skills to be acquired by students, to decide on teaching formats and methods to assess student learning, to draw up the teaching schedule, to define the statistical methods to be used to assess student satisfaction, and to perform the statistical analysis of results. Training in hospital hygiene and environmental safety was carried out through presentation of a relevant case. After being divided into groups the students attended the three units (Environmental Microbiology, Environmental Xenobiotics, Genetic Epidemiology and Molecular Biology) of the Hygiene Section of a Public Health Institute. Training in Organization and Health Programming involved presentation of a set of indicators for the definition of objectives and assessment of health systems or services. RESULTS: The literature search led to the identification of the relevant literature. With regard to student satisfaction, 96% of those who replied to the questionnaire gave an overall positive review of the training course (at least 3 on a scale from 1 to 5). CONCLUSIONS: the overall high level of student satisfaction suggests that the proposed model may be exportable. Further developments will be the assessment of trends regarding functioning of the organizational model and perceived teaching quality.

Suicidal or homicidal sharp force injuries? A review and critical analysis of the heterogeneity in the forensic literature.

The differential diagnosis between self-inflicted and nonself-inflicted, suicidal and homicidal, injuries is difficult or impossible in many cases and, above all, cannot be made on the basis of information obtained solely from the autopsy or the medicolegal clinical examination. The purpose of this study is to analyze the literature on suicidal and homicidal sharp force injuries and identify the relevant parameters that may help differentiate between suicidal and homicidal deaths. To achieve this goal, a review of 595 potentially relevant articles was performed. After excluding the nonrelevant papers by screening the titles, all abstracts were reviewed, and articles meeting the inclusion criteria underwent a full-text review. The following parameters were compiled into a table: number of cases, localization of the injuries, and number of injuries. The data were statistically analyzed and compared with those available in the forensic literature. On the basis of the heterogeneity of data revealed by the present review, a simple and short checklist of the parameters that should be included when reporting suicides and homicides by sharp force has been proposed.

[Comparison of conventional culture methods and quantitative real-time PCR methods for the detection of Legionella pneumophila in water samples in a large University teaching hospital in Rome, Italy]. / Confronto tra il metodo colturale standard e la real-time PCR per l'identificazione di Legionella pneumophila in campioni di acqua.

The aims of this study were to identify the best threshold value for the real-time PCR method in detecting the presence of Legionella pneumophila in water samples, and to evaluate the prognostic significance of negative results obtained with the molecular method. From 2011 to 2014, 77 water samples were collected from hospital wards of a large University teaching hospital in Rome (Italy) and screened for L.pneumophila by the standard culture method and by real-time PCR. The high sensitivity and negative predictive value of real-time PCR make this method suitable as a quick screening tool to exclude the presence of L. pneumophila in water samples in the hospital setting.

Non-fermentative gram-negative bacteria in hospital tap water and water used for haemodialysis and bronchoscope flushing: prevalence and distribution of antibiotic resistant strains.

This study provides a detailed description of the distribution of non-fermentative gram-negative bacteria (NFGNB) collected in water sources (tap water and water used for haemodialysis and bronchoscope flushing) from different wards of a tertiary care hospital. The aim is to identify risk practices for patients or to alert clinicians to the possible contamination of environment and medical devices. The resistance profile of NFGNB environmental isolates has shown that more than half (55.56%) of the strains isolated were resistant to one or more antibiotics tested in different antimicrobial categories. In particular, 38.89% of these strains were multidrug resistant (MDR) and 16.67% were extensively drug resistant (XDR). The most prevalent bacterial species recovered in water samples were Pseudomonas aeruginosa, Pseudomonas fluorescens, Ralstonia pickettii and Stenotrophomonas maltophilia. Analysis of antibiotic resistance rates has shown remarkable differences between Pseudomonadaceae (P. aeruginosa and P. fluorescens) and emerging pathogens, such as S. maltophilia and R. pickettii. Multidrug resistance can be relatively common among nosocomial isolates of P. aeruginosa, which represent the large majority of clinical isolates; moreover, our findings highlight that the emergent antibiotic resistant opportunistic pathogens, such as R. pickettii and S. maltophilia, isolated from hospital environments could be potentially more dangerous than other more known waterborne pathogens, if not subjected to surveillance to direct the decontamination procedures.

[Definition of "Safety and Hygiene Packages" as a management model for the Hospital Hygiene Service (HHS)]. / Definizione di "Pacchetti Sicurezza e Igiene" come modello organizzativo e gestionale per la sicurezza in Ospedale di un Servizio di Igiene Ospedaliera.

The purpose of this research is to identify and formalize the Hospital Hygiene Service activities and products, evaluating them in a cost accounting management view. The ultimate aim, is to evaluate the financial adverse events prevention impact, in an Hospital Hygiene Service management. A three step methodology based on affinity grouping activities, was employed. This methodology led us to identify 4 action areas, with 23 related productive processes, and 86 available safety packages. Owing to this new methodology, we was able to implement a systematic evaluation of the furnished services.

[Frequency of food-borne infections in an Italian region, before and after abolishing food worker health cards, 1996-2009]. / Studio comparativo delle notifiche di tossinfezioni alimentari in Italia, a livello regionale, prima e dopo l'abolizione del Libretto di Idoneità Sanitaria per gli operatori alimentaristi, nel periodo 1996-2009.

The authors present and discuss the results of a study performed in an Italian region, to compare the frequency of food-borne infections before and after abolishment of food worker health card requirements. Results confirm the efficacy of food safety training for food handlers, in accordance with evidence-based prevention data.

Legionella on board trains: effectiveness of environmental surveillance and decontamination.

BACKGROUND: Legionella pneumophila is increasingly recognised as a significant cause of sporadic and epidemic community-acquired and nosocomial pneumonia. Many studies describe the frequency and severity of Legionella spp. contamination in spa pools, natural pools, hotels and ships, but there is no study analysing the environmental monitoring of Legionella on board trains. The aims of the present study were to conduct periodic and precise environmental surveillance of Legionella spp. in water systems and water tanks that supply the toilet systems on trains, to assess the degree of contamination of such structures and to determine the effectiveness of decontamination. METHODS: A comparative pre-post ecological study was conducted from September 2006 to January 2011. A total of 1,245 water samples were collected from plumbing and toilet water tanks on passenger trains. The prevalence proportion of all positive samples was calculated. The unpaired t-test was performed to evaluate statistically significant differences between the mean load values before and after the decontamination procedures; statistical significance was set at p ≤ 0.05. RESULTS: In the pre-decontamination period, 58% of the water samples were positive for Legionella. Only Legionella pneumophila was identified: 55.84% were serogroup 1, 19.03% were serogroups 2-14 and 25.13% contained both serogroups. The mean bacterial load value was 2.14 × 10(3) CFU/L. During the post-decontamination period, 42.75% of water samples were positive for Legionella spp.; 98.76% were positive for Legionella pneumophila: 74.06% contained serogroup 1, 16.32% contained serogroups 2-14 and 9.62% contained both. The mean bacterial load in the post-decontamination period was 1.72 × 10(3) CFU/L. According to the t-test, there was a statistically significant decrease in total bacterial load until approximately one and a half year after beginning the decontamination programme (p = 0.0097). CONCLUSIONS: This study indicates that systematic environmental surveillance could be a useful approach for assessing the risk of exposure to Legionella bacteria, which still represents a public health threat. According to the study results, an environmental surveillance programme, followed by decontamination procedures where necessary, would decrease the total bacterial count, protecting the health of travellers and workers.