A quantitative microbiological risk assessment for Campylobacter in petting zoos

Cross-contamination in the kitchen: A model for quantitative microbiological risk assessment

A quantitative microbiological risk assessment model for the cross-contamination transmission route in the kitchen (KCC) is presented. Bacteria are transmitted from contaminated (chicken) meat to hands, kitchen utensils, and other surfaces, subsequently contaminating a salad. The model aims to estimate the fraction of bacteria on the meat that is ingested due to cross-contamination, determine the importance of the different transmission routes, and assess the effect of scenarios (interventions) on the fraction ingested. The cross-contamination routes defined, bacterial source-to-recipient transfer fractions as available and derived from literature, and important characteristics (e.g., washing in cold water vs. hot water with soap) shaped the KCC model. With this model, 32 scenarios of an eight-step preparation of a "meat and salad" meal in a domestic kitchen were stochastically simulated. The "cutting board-salad" route proved dominant and the salad plays a major role in the final exposure. A realistic scenario (washing hands, cutting board, and knife with cold water after cutting the meat) estimates that a mean fraction of 3.2E - 3 of the bacteria on the meat is ingested. In the case of "hand washing with hot water and soap" and "cutting board and knife replacement," the mean fraction ingested is 3.6E - 6. For a subsequent meal, where the contaminated sources were kitchen fomites, the estimated mean fraction is 4.3E - 4. In case of hamburger, part of the bacteria is unavailable for cross-contamination, resulting in a mean fraction ingested of about 5.4E - 5. The role of the dishcloth in cross-contamination transmission proved to be minor.

Is Personal Protective Equipment Worth the Hassle? Annual Risk of Cryptosporidiosis to Dairy Farmers and How Personal Protective Equipment and Handwashing Can Mitigate It

Cows are known carriers of Cryptosporidium parvum (C. parvum), a protozoa that can cause the gastrointestinal illness cryptosporidiosis in humans. Despite this potential exposure, dairy farmers tend to wear personal protective equipment (PPE) to protect the milk from contamination, rather than to protect themselves from zoonotic diseases, such as cryptosporidiosis. In this study, cow feces were collected from individual cattle on dairy farms and analyzed for C. parvum using qPCR. Quantitative microbial risk assessment (QMRA) was used to determine the risk of cryptosporidiosis to the dairy farmer with and without the use of handwashing and PPE (gloves and masks). The annualized risk of cryptosporidiosis to dairy farmers was 29.08% but was reduced significantly in each of the three interventions. Among the individual interventions, glove use provided the greatest reduction in risk, bringing the annual risk of cryptosporidiosis to 4.82%. Implementing regular handwashing, the use of gloves and a mask brought the annual risk of cryptosporidiosis to 1.29%. This study provides evidence that handwashing and PPE use can significantly reduce the risk of cryptosporidiosis to farmers and is worth implementing despite potential barriers such as discomfort and cost.

Application of hydraulic modelling and quantitative microbial risk assessment (QMRA) for cloudburst management in cities with combined sewer systems

Urban cloudburst management may include the intentional temporary storage of flood water in green recreational areas. In cities with combined sewers, this will expose the population visiting the area to sewage and increase the risk of diarrhoeal disease. We present a unique approach to estimate the risk of diarrhoeal disease after urban flooding. The exposure scenario was: rainwater mixed with sewage flows into a park; sewage with pathogens deposit on the grass; after discharge, a baby plays on the grass and is exposed to the pathogens in the deposited sewage by hand-to-mouth transfer. The work included modelling the transport of sewage into four parks intended to be flooded during future cloudbursts. A flood simulation experiment was conducted to estimate the deposition of pathogens from sewage to grass and transfer from grass to hand. Hand-to-mouth transfer, based on literature values, was used to estimate the ingested dose of pathogens. The probability of illness was estimated by QMRA. The estimated average probability of illness varied between 0.03 and 17%. If the probability of illness is considered unacceptable, the cloudburst plans should be changed, or interventions, e.g. informing the public about the risk or restricting access to the flooded area, should be implemented.

Mobile Zoos and Other Itinerant Animal Handling Events: Current Status and Recommendations for Future Policies

Mobile zoos are events in which non-domesticated (exotic) and domesticated species are transported to venues such as schools, hospitals, parties, and community centres, for the purposes of education, entertainment, or social and therapeutic assistance. We conducted literature searches and surveyed related government agencies regarding existing provisions within laws and policies, number of mobile zoos, and formal guidance issued concerning operation of such events in 74 countries or regions. We also examined governmental and non-governmental guidance standards for mobile zoos, as well as websites for mobile zoo operations, assessed promotional or educational materials for scientific accuracy, and recorded the diversity of species in use. We used the EMODE (Easy, Moderate, Difficult, or Extreme) algorithm, to evaluate identified species associated with mobile zoos for their suitability for keeping. We recorded 14 areas of concern regarding animal biology and public health and safety, and 8 areas of false and misleading content in promotional or educational materials. We identified at least 341 species used for mobile zoos. Mobile zoos are largely unregulated, unmonitored, and uncontrolled, and appear to be increasing. Issues regarding poor animal welfare, public health and safety, and education raise several serious concerns. Using the precautionary principle when empirical evidence was not available, we advise that exotic species should not be used for mobile zoos and similar itinerant events.

Bacterial zoonoses transmitted by household pets and as reservoirs of antimicrobial resistant bacteria

Numerous individuals are committed to growing pet creatures like cats, dogs, and rats etc., pay care for them and as a result of this, there's a boost of their populace in advanced culture. The close interaction between family pets and individuals offers ideal conditions for bacterial transmission. Distinctive sorts of antimicrobial agents are exploited for animal husbandry and studies have revealed that many bacteria have attained confrontation against them viz., Staphylococcus intermedius, Escherichia coli, methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococci and multidrug-resistant Salmonella typhi etc. and a few of these are a prospective for zoonotic transmission. In the current review, the attention has been paid on how household pets, especially dogs disperse the antimicrobial resistance in contrast to that of food animals. A lot of evidences are accessible on food animals and nation-wide scrutiny programmes solely hub on food animals; therefore, for steerage antimicrobial use policy in small animal veterinary exercise as well as for gauging the chance of transmission of antimicrobial resistance to humans' statistics on pet animals are sincerely needed. Transmission of such organisms, especially pathogenic staphylococci, occurs between pets, owners, and veterinary staff, and pets can act as reservoirs of such bacteria; this may additionally have an impact on the use of antimicrobials in human medicine. There is a need to generate statistics concerning each the levels of carriage of such microorganism in pets and the risk factors associated with the switch of the microorganism to human beings who have contact with infected pets, as nicely as to improve hygiene measures in veterinary practice.

Measuring animal exposure in Canada: Foodbook study, 2014-2015

Animal companionship can have many physical and psychological benefits; however, animals can also be a source of zoonotic infection, including enteric illnesses; it has been estimated that in Canada, nearly 85,000 enteric illnesses due to eight pathogens occur each year related to animal contact. There is a lack of baseline data on animal-related exposures in Canada and around the world. This information is critical to inform quantitative and qualitative risk assessments to prioritize intervention efforts in public health and reduce the associated burden of enteric illness. To help address this issue and assist evaluation of the risks associated with animal contact, the Foodbook study, conducted in 2014-2015, assessed exposure to animals, animal food and animal-related venues within the last 7 days among Canadians. Data were analysed by province and territory, age group and urban/rural residency. Overall, dogs and cats were the most commonly reported animal exposures (43.3% and 31.9%, respectively). The data suggest farm animal exposure occurs primarily at a farm/barn, and to a lesser extent at other animal-related venues (e.g., petting zoos or agricultural fairs). Approximately one in 25 respondents handled raw pet food within the last 7 days; the majority of which had also been exposed to a dog (86.4%). Children aged 0-9 years reported relatively high exposure to four types of high-risk animals: rodents (5.6%), poultry (4.0%), reptiles (2.1%) and amphibians (1.8%); with the most vulnerable children aged <5 years also reporting exposure to many of these high-risk animals. These results highlight potential areas for targeted intervention that can focus on high-risk populations (e.g., young children) exhibiting potentially risky behaviour such as being exposed to certain high-risk animals, or handling pet food, treats and raw pet food diets. Additionally, these results support the need to better understand the burden of enteric illness associated with animals and their environments.

Multi-Exposure Pathway Model to Compare Escherichia coli O157 Risks and Interventions

The relative contributions of exposure pathways associated with cattle-manure-borne Escherichia coli O157:H7 on public health have yet to be fully characterized. A stochastic, quantitative microbial risk assessment (QMRA) model was developed to describe a hypothetical cattle farm in order to compare the relative importance of five routes of exposure, including aquatic recreation downstream of the farm, consumption of contaminated ground beef processed with limited interventions, consumption of leafy greens, direct animal contact, and the recreational use of a cattle pasture. To accommodate diverse environmental and hydrological pathways, existing QMRAs were integrated with novel and simplistic climate and field-level submodels. The model indicated that direct animal contact presents the greatest risk of illness per exposure event during the high pathogen shedding period. However, when accounting for the frequency of exposure, using a high-risk exposure-receptor profile, consumption of ground beef was associated with the greatest risk of illness. Additionally, the model was used to evaluate the efficacy of hypothetical interventions affecting one or more exposure routes; concurrent evaluation of multiple routes allowed for the assessment of the combined effect of preharvest interventions across exposure pathways-which may have been previously underestimated-as well as the assessment of the effect of additional downstream interventions. This analysis represents a step towards a full evaluation of the risks associated with multiple exposure pathways; future incorporation of variability associated with environmental parameters and human behaviors would allow for a comprehensive assessment of the relative contribution of exposure pathways at the population level.

A Comparative Exposure Assessment of Campylobacter in Ontario, Canada

To inform source attribution efforts, a comparative exposure assessment was developed to estimate the relative exposure to Campylobacter, the leading bacterial gastrointestinal disease in Canada, for 13 different transmission routes within Ontario, Canada, during the summer. Exposure was quantified with stochastic models at the population level, which incorporated measures of frequency, quantity ingested, prevalence, and concentration, using data from FoodNet Canada surveillance, the peer-reviewed and gray literature, other Ontario data, and data that were specifically collected for this study. Models were run with @Risk software using Monte Carlo simulations. The mean number of cells of Campylobacter ingested per Ontarian per day during the summer, ranked from highest to lowest is as follows: household pets, chicken, living on a farm, raw milk, visiting a farm, recreational water, beef, drinking water, pork, vegetables, seafood, petting zoos, and fruits. The study results identify knowledge gaps for some transmission routes, and indicate that some transmission routes for Campylobacter are underestimated in the current literature, such as household pets and raw milk. Many data gaps were identified for future data collection consideration, especially for the concentration of Campylobacter in all transmission routes.