Prevent Pathogen Transmission Research Articles

The Utilization of Native Freshwater Mussel <i>Pilsbryoconcha exilis</i> as Biocontrol of Pathogenic Bacteria <i>Aeromonas hydrophila</i> in Tilapia Aquaculture

This research aims to evaluate the capacity of freshwater mussel Pilsbryoconcha exilis as a biocontrol agent to prevent the transmission of Aeromonas hydrophila in tilapia cultivation. Briefly, 10 tilapia fish with average bodyweight 7,88±0,25 g were subjected to four treatments in the 8-liter aquarium with three replications in a randomized design trial. The treatments were M1 (one mussel for a two-liter of water), M2 (two mussels for a two-liter of water), and two control treatments without mussel ( M+ and M-). All treatments, except the M-, then challenged by adding A. hydrophila live culture to obtain a final density of 105 CFU mL-1 into the aquarium for 7 days duration. The final survival rate of fish, the water-total bacterial count, and the blood profile of animals were assessed. The research revealed that there is a significant impact from the presence of freshwater mussel on tilapia cultivation. Generally, the M2 treatment showed better results with a significant different (P<0,05) according to the survival rate of fish (100±0,00%), water-total bacterial count (4,53±0,03 log CFU mL-1), and fish leucocytes (4,30±0,70x104 cell mm-3). Nonetheless, there was no different (P>0,05) effect on fish erythrocytes among the treatments. Therefore, the feeding activity of freshwater mussel in the water column able to deplete pathogenic bacteria abundance and prevent pathogen transmission along with increasing the survival rate of fish.

Assessment of percent positive agreement between fluorescent marker and ATPase for environmental cleaning monitoring during sequential application in an intensive care unit

Terminal room cleaning is critical in preventing pathogen transmission; however, the optimal cleaning effectiveness assessment modality is still being investigated. We sequentially compared cleanliness assessment agreement between a fluorescent marker and an adenosine triphosphate bioluminescence method, finding no significant differences between modalities.

Photoinactivation of bacteria by hypocrellin-grafted bacterial cellulose

With the aim of developing self-disinfecting materials to prevent pathogen transmission from surfaces to new hosts, here we report a simple and eco-friendly way to prepare photodynamic bacterial cellulose (BC) onto which the naturally-occurring photosensitizer hypocrellin (Hc) has been covalently appended. The resultant hypocrellin-grafted BC membrane (Hc-BC) was characterized by both physical (SEM, TGA, XRD) and spectroscopic (IR, diffuse reflectance UV–visible) methods, and the photosensitizer loading was found to be 155 nmol Hc/mg membrane. Indirect cytotoxicity tests employing mouse skin fibroblast (L929) cells showed no changes in cell viability, demonstrating that the Hc-BC membrane lacked any leachable components (e.g., unreacted coupling agent or hypocrellin) that could be cytotoxic to mammalian cells. The photodynamic antibacterial activity of Hc-BC was evaluated against gram-positive S. aureus (ATCC-6538) and gram-negative E. coli strain 8099. Our results demonstrated a 99.5 + % (2.7 log units) reduction in S. aureus upon illumination (Xe lamp, 65 ± 5 mW/cm2, 420–780 nm; 30 min), however, no statistically significant inactivation of E. coli was observed. Potentiation with potassium iodide was found to increase the antibacterial efficacy of Hc-BC against S. aureus to 99.997% (4.8 log units) at 10 mM KI, while E. coli was inactivated by 99.1% (2 log units) at 100 mM KI, with the increase in inactivation being attributable to short-lived reactive iodide radicals that are the major biocidal agents in the potentiation of Hc-BC by KI. Taken together, our findings demonstrated that hypocrellin-grafted bacterial cellulose is a sustainable material from which potent photodynamic antibacterial materials may be derived.

Increasing Patient Accessibility and Use of Hand Sanitizer Through Introduction of a Single-Dose Packet

BACKGROUND Preventing pathogen transmission via healthcare worker (HCW) hand hygiene (HH) is well-established. Emerging evidence suggests patients contaminate their environment with their flora and acquire pathogens on their hands through HCW and environment contact; therefore, there has been increasing interest in patient HH despite lack of guidance. Single-dose hand sanitizer packets (SDP) were evaluated as a solution for accessible patient HH. METHODS In a 270-bed hospital, Infection Preventionist randomly solicited patient participation in a study during daily rounds. Patients between September 4–17, 2018 were assigned to the control group (n=32), patients between September 18–November 28, 2018 were assigned to the intervention (n=35). A 7-question baseline survey assessing sanitizer accessibility and HH practices was distributed to the control group. The intervention group received a 24-count SDP via admission kit. Participants were not instructed how/when to use the SDP. A 9-question survey was distributed to the intervention group, including questions on hand cleaning practices, sanitizer accessibility, and evaluation of SDP. Results were analyzed with an independent samples t-test (α=0.05). RESULTS The intervention group reported higher access to hand sanitizer than the control (mean of 5-point scale, 4.8 and 3.5, respectively; p˂0.001). Patients in the intervention group had higher sanitizer usage (mean of 4-point scale, 3.8 and 2.7, respectively; p˂0.001) and rated higher that they were able to keep their hands germ-free (mean of 5-point scale, intervention 4.7 and control 3.7; p˂0.001). Soap and water usage was higher in the control group (mean of 4-point scale, control 3.2 and intervention 2.4; p=0.003). CONCLUSIONS Patients reported that SDP increased sanitizer accessibility, helped keep their hands germ-free, and increased their hand sanitizer usage. Considering limitations around sink and wall dispenser accessibility and cost constraints with providing patients individual sanitizer bottles, SDP could be a promising solution for admission kits.

Microbial study of household hygiene conditions and associated Listeria monocytogenes infection risks for Peruvian women.

To develop an exposure and risk assessment model to estimate listeriosis infection risks for Peruvian women. A simulation model was developed utilising Listeria monocytogenes concentrations on kitchen and latrine surfaces in Peruvian homes, hand trace data from Peruvian women and behavioural data from literature. Scenarios involving varying proportions of uncontaminated, or 'clean', surfaces and non-porous surfaces were simulated. Infection risks were estimated for 4, 6 and 8 h of behaviours and interactions with surfaces. Although infection risks were estimated across scenarios for various time points (e.g. 4, 6, 8 h), overall mean estimated infection risks for all scenarios were ≥ 0.31. Infection risks increased as the proportions of clean surfaces decreased. Hand-to-general surface contacts accounted for the most cumulative change in L. monocytogenes concentration on hands. In addition to gaining insights on how human behaviours affect exposure and infection risk, this model addressed uncertainties regarding the influence of household surface contamination levels. Understanding the influence of surface contamination in preventing pathogen transmission in households could help to develop intervention strategies to reduce L. monocytogenes infection and associated health risks.

Effectiveness of an edutainment video teaching standard precautions \u2013 a randomized controlled evaluation study

BackgroundStandard precautions are essential to prevent pathogen transmission and nosocomial infections. We assessed learning effect (primary outcome) and satisfaction (secondary outcome) of watching a 5-min humorous “edutainment (=education and entertainment) video” on Standard Precautions compared to reading a written standard operating procedure (SOP) or receiving no intervention.MethodsThis randomized controlled trial was executed at the University Hospital Zurich, Switzerland, a tertiary care centre with a state-of-the-art infection prevention programme. Healthcare providers (HCPs) of different medical departments were 1:1:1 randomized to watching the edutainment video (video group), reading the SOP (SOP group), or no study-specific intervention (no-intervention group). Online questionnaires included a knowledge assessment about Standard Precautions at time point (TP) 1 immediately after intervention, TP2 after 1 month, and TP3 after 3 months. Information about HCPs’ satisfaction with the learning method was collected. Variables were assessed within and between groups using the appropriate non-parametric tests. Predictors for knowledge of Standard Precautions were assessed by uni- and multivariable linear regression.ResultsOverall, 363 predominantly female (78.2%) HCPs were included. At TP 1 and TP3, the video group scored better on the knowledge assessment against both the SOP and the no-intervention group (TP1 p < .001 and 0.001, TP3 p = 0.036 and 0.048). In the multivariable analysis, being member of the video group was an independent predictor for better knowledge scores. The video was rated higher than the SOP regarding satisfaction with learning experience, and video group participants more frequently indicated they would recommend their learning method to colleagues.ConclusionsWatching an edutainment video proved to be more effective to improve knowledge about Standard Precautions compared to reading an SOP or no intervention. Satisfaction with the learning method was superior in the video group, suggesting higher potential for future uptake.

Identification of Leishmania Species in Naturally Infected Sand Flies from Refugee Camps, Greece.

High infection rates of Leishmania donovani and L. tropica were detected in Phlebotomus spp. sand flies collected from refugee camps in Greece, indicating increased risk of infection among local populations. Detection and treatment of leishmaniasis, community education, and vector control are essential measures to prevent pathogen transmission and protect public health.

An outbreak of trichomonosis in European greenfinches Chloris chloris and European goldfinches Carduelis carduelis wintering in Northern France.

Avian trichomonosis is a common and widespread disease, traditionally affecting columbids and raptors, and recently emerging among finch populations mainly in Europe. Across Europe, finch trichomonosis is caused by a single clonal strain of Trichomonas gallinae and negatively impacts finch populations. Here, we report an outbreak of finch trichomonosis in the wintering populations of Chloris chloris (European greenfinch) and Carduelis carduelis (European goldfinch) from the Boulonnais, in northern France. The outbreak was detected and monitored by bird ringers during their wintering bird ringing protocols. A total of 105 records from 12 sites were collected during the first quarter of 2017, with 46 and 59 concerning dead and diseased birds, respectively. Fourteen carcasses from two locations were necropsied and screened for multiple pathogens; the only causative agent identified was T. gallinae. Genetic characterization was performed by four markers (small subunit ribosomal RNA, hydrogenosomal iron-hydrogenase, and RNA polymerase II subunit 1 genes, and the internal transcribed spacers (ITS) region) and confirmed the T. gallinae strain to be A1, which affects the finch populations of Europe. This was also confirmed by an ITS-based phylogenetic analysis which further illustrated the diversity of the Trichomonas infecting birds. Preliminary data on the survival and dispersion of infected birds were obtained from ring-returns of diseased individuals. The anthropogenic spread of diseases through bird feeding practices is highlighted and some suggestions to prevent pathogen transmission via backyard supplementary feeders for garden birds are given.

Differential expression of carboxylesterases in larva and adult of Culex quinquefasciatus Say (Diptera: Culicidae) from sub-Himalayan West Bengal, India

AbstractCulex quinquefasciatusSay, a widely distributed mosquito in tropical and subtropical areas, is the most important vector of the filarial parasiteWuchereria bancrofti, the causative agent of lymphatic filariasis. In India, filariasis is endemic in 17 States and six Union Territories, putting about 553 million people at risk of infection. Vector control, which aims to prevent pathogen transmission through interventions targeting adult mosquito vectors, is a significant component of control of the disease. Chemical-based control represents a chief strategy in the management of mosquito vectors; however, continuous application of insecticides has led to the development of resistance in many mosquito vectors around the world. The current study aims to observe the variability of expression of carboxylesterase isozymes that play a role in detoxifying insecticides into non-toxic compounds, in different life stages ofCulexmosquitoes, to understand levels of insecticide susceptibility that may be used in integrated mosquito management for efficient vector control.C. quinquefasciatus werecollected from different localities of sub-Himalayan West Bengal, India, and adult and larval bioassays were performed against one organophosphate insecticide (chlorpyrifos) and two synthetic pyrethroid insecticides (deltamethrin and lambda-cyhalothrin). The activity of α- and β-carboxylesterases (quantitative assay) were measured in larvae and adults ofC. quinquefasciatususing a microplate assay, and measured qualitative expression by native polyacrylamide gel electrophoresis. The study shows a differential activity of α- and β-carboxylesterases both in quantitative and qualitative assays. The quantitative assay reveals that larvae exhibit a 12.2-fold higher level activity of α-carboxylesterase and about 5.0-fold higher level of activity of β-carboxylesterase than adults. Some carboxylesterase isozymes, i.e., α-Est I-IV, α-Est VII and α-Est XI-XV were exclusively expressed in larvae, whereas α-Est V-VI and α-Est IX were expressed only in adults. In larvae, all β-Est I-IX were expressed, while in adults only β-Est IV-V was expressed. The results of adult and larval insecticide bioassay are also as per the above findings showing an LC90value of 0.017 ppm, 0.097 ppm and 0.072 ppm in the larva, and LC90value of 0.0015 ppm, 0.721 ppm, 0.364 ppm in adults against chlorpyrifos, deltamethrin and lambda-cyhalothrin, respectively.

Strain, disinfectant, concentration, and contact time quantitatively impact disinfectant efficacy

BackgroundTransmission of healthcare-associated infections caused by antibiotic- and multi-drug resistant (MDR) pathogens (e.g. Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa) are a major concern in patient care facilities. Disinfectant usage is critical to control and prevent pathogen transmission, yet the relationships among strain, disinfectant type, contact time, and concentration are not well-characterized. We hypothesized that there would be significant differences in disinfectant efficacy among clinically relevant strains under off-label disinfectant conditions, but there would be less no differences among at registered label use concentrations and contact times. The purpose of this study was to quantify the effect of disinfectant concentration and contact time on the bactericidal efficacy of clinically relevant strains of S. aureus and P. aeruginosa.MethodsAccelerated hydrogen peroxide (AHP), quaternary ammonium compounds (Quat), and sodium hypochlorite were tested at label and reduced contact times and concentrations against four MDR P. aeruginosa strains and four MRSA strains. Quantitative EPA method MB-25-02 was used to measure disinfectant efficacy reported as log10 reduction.ResultsBoth off-label disinfectant concentrations and contact times significantly affected efficacy of all disinfectants tested. Bactericidal efficacy varied among MRSA and P. aeruginosa strains.ConclusionsThe quantitative disinfectant efficacy method used highlights the inter-strain variability that exists within a bacterial species. It also underscores the need for a disinfectant validation method that takes these variances into account.

Behavioral Plasticity in Probing by Diaphorina citri (Hemiptera, Liviidae): Ingestion from Phloem Versus Xylem is Influenced by Leaf Age and Surface

Diaphorina citri is a major pest of citrus because it transmits Candidatus Liberibacter asiaticus, a phloem-limited bacterium that putatively causes Huanglongbing (HLB). The disease moves slowly through a tree, and the vector facilitates further within-tree movement via transmission of the pathogen. However, this only happens when D. citri stylets contact the phloem, to inoculate bacteria during phloem salivation and acquire bacteria during phloem sap ingestion. Behavioral changes in D. citri associated with different plant parts would affect how long it takes to reach phloem and how long the psyllids stays in phloem to ingest, thereby influencing the risk of disease spread. D. citri feeding was recorded on the abaxial and adaxial surfaces of mature and immature citrus leaves. Adults in the field can be found on these surfaces at all times of year. On abaxial surface of immature leaves, phloem salivation would occur after 11 h on average, but rarely as soon as 0.56 h. The corresponding values on mature leaves were 16 and 2.7. In general, psyllids spent more time ingesting phloem sap on immature leaves than on mature leaves. Psyllids on abaxial surfaces spent more time ingesting from phloem, though the strength of this effect was less than for immature versus mature leaves. In contrast, xylem ingestion increased on mature leaves compared with young. The biological differences that could produce this outcome are discussed. The results discussed herein are of relevance to further studies on the efficacy of an insecticide to act quickly enough to prevent pathogen transmission.

Molecular detection and phylogenetic analysis of tick-borne pathogens in wild Korean water deer and farmed elk in Gyeongbuk and Gangwon Provinces of Korea.

The purpose of this study was to assess tick-borne pathogenic infections in 42 wild Korean water deer (KWD) and 26 farmed elk in the Gyeongbuk and Gangwon Provinces of Korea. Among the 42 wild KWD tested, the eighteen (42.9%) and five (11.9%) samples tested positive for Anaplasma phagocytophilum and A. bovis, respectively, by PCR and DNA sequencing. All positive samples were only from wild KWD. All samples were negative for other tick-borne pathogens tested. Detected 16S rRNA sequences of A. phagocytophilum and A. bovis showed 98.6–99.8% and 94.4–100% identity to those of sequences in GenBank, respectively. Because few studies have examined tick-borne pathogens in wild animals, appropriate control programs and studies are needed to prevent pathogen transmission.

Novel CRISPR/Cas9 gene drive constructs reveal insights into mechanisms of resistance allele formation and drive efficiency in genetically diverse populations.

A functioning gene drive system could fundamentally change our strategies for the control of vector-borne diseases by facilitating rapid dissemination of transgenes that prevent pathogen transmission or reduce vector capacity. CRISPR/Cas9 gene drive promises such a mechanism, which works by converting cells that are heterozygous for the drive construct into homozygotes, thereby enabling super-Mendelian inheritance. Although CRISPR gene drive activity has already been demonstrated, a key obstacle for current systems is their propensity to generate resistance alleles, which cannot be converted to drive alleles. In this study, we developed two CRISPR gene drive constructs based on the nanos and vasa promoters that allowed us to illuminate the different mechanisms by which resistance alleles are formed in the model organism Drosophila melanogaster. We observed resistance allele formation at high rates both prior to fertilization in the germline and post-fertilization in the embryo due to maternally deposited Cas9. Assessment of drive activity in genetically diverse backgrounds further revealed substantial differences in conversion efficiency and resistance rates. Our results demonstrate that the evolution of resistance will likely impose a severe limitation to the effectiveness of current CRISPR gene drive approaches, especially when applied to diverse natural populations.

Transmission of the gut microbiota: spreading of health.

Transmission of commensal intestinal bacteria between humans could promote health by establishing, maintaining and replenishing microbial diversity in the microbiota of an individual. Unlike pathogens, the routes of transmission for commensal bacteria remain unappreciated and poorly understood, despite the likely commonalities between both. Consequently, broad infection control measures that are designed to prevent pathogen transmission and infection, such as oversanitation and the overuse of antibiotics, may inadvertently affect human health by altering normal commensal transmission. In this Review, we discuss the mechanisms and factors that influence host-to-host transmission of the intestinal microbiota and examine how a better understanding of these processes will identify new approaches to nurture and restore transmission routes that are used by beneficial bacteria.

Evaluating the cleaning procedures of meat slicers at retail delis in Metro Vancouver

&#x0D; Background: Ready-to-eat deli meats are widely consumed by the public; however they are also a high risk food for carrying Listeria monocytogenes. Listeriosis, an infection that can result from consumption of Listeria monocytogenes contaminated food, is the leading cause of deaths related to foodborne illness in Canada. Due to structural constraints and inadequate cleaning, mechanical slicers used to process deli meats have been implicated as a major source of Listeria monocytogenes contamination of deli meats. Several governing bodies, including local health authorities have published recommendations on the proper method of cleaning and sanitizing meat slicers to prevent the risk of contamination of deli meats. This study evaluated the compliancy of retail delis in Metro Vancouver to these recommendations and also assessed their knowledge of the risk associated with deli meats. Methods: An in-person, self-administered paper survey was conducted at several retail delis and supermarkets. The survey questions determined the cleaning and sanitation procedures of meat slicers at the establishments and also assed knowledge of the risk associated with deli meats. Both nominal and numerical data was collected and analyzed using a Chi-squre test and a t-test. Results: Based on the data collected, a statistically significant difference was identified between the cleaning procedures practiced by the establishments and those recommended to prevent pathogen transmission through meat slicers. The chi-square test revealed that there is a statistically significant association between the size of the establishment and the adequacy of cleaning procedures, with small-scale delis being less likely to comply with the cleaning practices that are recommended by governing bodies. Conclusion: Cleaning procedures practiced at retail delis and supermarkets are not consistent with those recommended by regulatory agencies to prevent the transmission of pathogens such as Listeria monocytogenes from meat slicers to deli meats. Smaller retail delis are less likely to follow proper cleaning methods than larger supermarket delis. Educational intervention by health authorities may be needed to ensure that food establishments are informed of proper and timely cleaning procedures.&#x0D;

Human quarantine: Toward reducing infectious pressure on chimpanzees at the Taï Chimpanzee Project, Côte d'Ivoire.

Due to their genetic relatedness, great apes are highly susceptible to common human respiratory pathogens. Although most respiratory pathogens, such as human respiratory syncytial virus (HRSV) and human metapneumovirus (HMPV), rarely cause severe disease in healthy human adults, they are associated with considerable morbidity and mortality in wild great apes habituated to humans for research or tourism. To prevent pathogen transmission, most great ape projects have established a set of hygiene measures ranging from keeping a specific distance, to the use of surgical masks and establishment of quarantines. This study investigates the incidence of respiratory symptoms and human respiratory viruses in humans at a human‐great ape interface, the Taï Chimpanzee Project (TCP) in Côte d'Ivoire, and consequently, the effectiveness of a 5‐day quarantine designed to reduce the risk of potential exposure to human respiratory pathogens. To assess the impact of quarantine as a preventative measure, we monitored the quarantine process and tested 262 throat swabs for respiratory viruses, collected during quarantine over a period of 1 year. Although only 1 subject tested positive for a respiratory virus (HRSV), 17 subjects developed symptoms of infection while in quarantine and were subsequently kept from approaching the chimpanzees, preventing potential exposure in 18 cases. Our results suggest that quarantine—in combination with monitoring for symptoms—is effective in reducing the risk of potential pathogen exposure. This research contributes to our understanding of how endangered great apes can be protected from human‐borne infectious disease.

Determinants of chronic otitis media with effusion in preschool children: a case\u2013control study

BackgroundChronic otitis media with effusion (COME) is a prevalent upper airway infection resulting in hearing loss. The aim of this research was to determine risk factors for COME in preschool children.MethodsA case–control design was conducted in Auckland, New Zealand from May 2011 until November 2013. The cases were children aged 3 and 4 years referred for tympanostomy tube placement due to a diagnosis of COME (n = 178). The controls were a random sample of healthy children aged 3 and 4 years from primary care practices (n = 209). The children’s guardians completed an interviewer-administered questionnaire that covered topics including socio-demographic information, pregnancy and birth, infant feeding practices, home environment, and respiratory health. In addition, skin prick tests for atopy were performed. Odds ratios (OR) estimating the risk of COME independently associated with the exposures were calculated using a logistic regression model.ResultsChildren with COME frequently had nasal obstruction (OR: 4.38 [95% CI: 2.37–8.28]), always snored (OR: 3.64 [95% CI: 1.51–9.15]) or often snored (OR: 2.45 [95% CI: 1.04–5.96]), spent more hours per week in daycare (OR per hour/week: 1.03 [95% CI: 1.00–1.05]), had frequent colds (OR: 2.67 [95% CI: 1.59–4.53]), had siblings who had undergone tympanostomy tube placement (OR: 2.68 [95% CI: 1.22–6.02]), underwent long labour (OR: 2.59 [95% CI: 1.03–6.79]), and had early introduction of cow’s milk (OR: 1.76 [95% CI: 1.05–2.97]). Asian ethnicity (OR: 0.20 [95% CI: 0.07–0.53]) and having older siblings (OR: 0.54 [95% CI: 0.31–0.93]) were inversely associated with COME.ConclusionCOME in preschool children was associated with pathogen exposure, respiratory infection, and nasal obstruction. Strategies to prevent pathogen transmission warrant investigation. The novel findings of long labour and early cow’s milk introduction require replication in future studies.

Thiol-ol Chemistry for Grafting of Natural Polymers to Form Highly Stable and Efficacious Antibacterial Coatings.

Bacterial contamination of surfaces and the associated infection risk is a significant threat to human health. Some natural antibacterial polymers with low toxicity are promising coating materials for alleviating pathogenic colonization on surfaces. However, widespread application of these polymers as antibacterial coatings is constrained by coating techniques which are not easily scalable due to stringent reaction conditions. Herein, thiol-ol reaction involving oxidative conjugation between thiol and hydroxyl groups is demonstrated as a facile technique to graft two natural polymer derivatives, agarose (AG) and quaternized chitosan (QCS), as antibacterial coatings on polymer and metal substrates. The substrate surfaces are first treated with oxygen plasma followed by UV-induced grafting of the polymers under atmospheric conditions. Dimercaprol, a FDA-approved drug, is used as both surface anchor and cross-linker of the polymer chains during grafting. The AG coating achieves >2 log reduction in Pseudomonas aeruginosa and Staphylococcus aureus biofilm formation, while the QCS coating reduces bacterial count from contaminated droplets on its surface by >95%. The coatings are noncytotoxic and exhibits a high degree of stability under conditions expected in their potential applications as antibacterial coating for biomedical devices (for AG), and for preventing pathogen transmission in the environment (for QCS).

Role of food in environmental transmission of Helicobacter pylori.

Helicobacter pylori (H.pylori) is a gram-negative bacterium that has infected more than half of the world's population. This pathogen colonizes the human gastric mucosa and is usually acquired during childhood. It is an important cause of peptic ulcers, chronic gastritis and stomach cancer. Among the risk factors for acquisition of H. pylori infection, poor socioeconomic status, poor sanitization and hygiene practices, and contaminated food and water, are the most significant ones. The main route of H. pylori transmission is still unknown. Studies show that H.pylori bacteria can spread directly from one person to the other, or indirectly from an infected person to the environment. Person to person transmission is divided into fecal-oral, gastric-oral, oral-oral, sexual routes. Presently, interpersonal pathways are more acceptable than environmental exposure routes. Literatures indicate the presence and survival of H. pylori in food samples, such as milk, vegetables and meat, and suggest these foods may play an important role in the environmental transmission of this pathogen. In addition, other studies report the presence of H. pylori in the gastric tissue of some animals (e.g. sheep and cow) and therefore, it is likely they participate in the food chain transmission as reservoirs besides human. Although there are findings which indicate the probable role of food products in the environmental transmission of H. pylori, there is still not enough direct evidence to confirm this and more studies are needed. However, attention to food contamination sources (unhygienic water) and controlling them may prevent transmission of pathogens associated with health.

Smartphone text message service to foster hand hygiene compliance in health care workers.

Health care-associated infections are a major worldwide public health issue. Hand hygiene is a major component in the prevention of pathogen transmission in hospitals, and hand hygiene adherence by health care workers is low in many studies. We report an intervention using text messages as reminders and feedback to improve hand hygiene adherence. The study is a historical comparison proof-of-concept study. Eighteen health care workers were monitored during 12 months by a radiofrequency identification system. Afterward we sent 2 types of text messages, congratulation or encouragement, and we studied the evolution of hand hygiene adherence. We recorded 15,723 hand hygiene opportunities, 8,973 before intervention and 6,750 during and after the intervention. Using a multilevel logistic regression analysis, we found a significant increase in hand hygiene adherence during the intervention (odds ratio, 1.68) compared with the historical period. Despite limitations due to the type of study, a text message encouraging personnel to be more vigilant is effective in increasing hand hygiene adherence in health care workers. Text message feedback should be incorporated into multimodal approaches for improving hand hygiene compliance.