scholarly journals Risk Factors for Positivity to Shiga Toxin-Producing Escherichia coli and Salmonella enterica in Backyard Production Systems Animals from Metropolitana Region, Chile: A Threat to Public Health?

Author(s):  
Erika Pavez-Muñoz ◽  
Bastián Fernández-Sanhueza ◽  
Constanza Urzúa-Encina ◽  
Nicolás Galarce ◽  
Raúl Alegría-Morán

In the Metropolitana region of Chile there are 3836 backyard production systems (BPS), characterized as small-scale systems. They act as a source of zoonotic pathogens, such as Salmonella enterica and Shiga toxin-producing Escherichia coli (STEC), whose prevalence in BPS has not been fully described. The objective of this study was to determine the positivity for both agents in BPS and to establish the risk factors related to their presence. In each BPS, an epidemiological survey was undertaken, and stool samples were collected to detect these pathogens via bacteriological culture and conventional PCR techniques. Subsequently, multivariable logistic regression models were applied to establish the risk factors associated with their presence. BPS positivity rates of 11.76% for STEC and 4.7% for S. enterica were observed. The systems showed poor welfare standards and a lack of biosecurity measures. The risk factor analysis concluded that the Gini–Simpson index (p = 0.030; OR = 1.717) and the presence of neighboring intensive poultry or swine production systems (p = 0.019; OR = 20.645) act as factors that increased the risk of positivity with respect to STEC. In the case of S. enterica, exchanging embryonated eggs (p = 0.021; OR = 39) and the presence of debeaked chickens (p = 0.001; OR = 156) were determined as factors that increased the risk of positivity for this agent. For positivity with respect to both pathogens, the Gini–Simpson index (p = 0.030; OR = 1.544) and being INDAP/PRODESAL users (p = 0.023; OR = 15.026) were determined as factors that increased the risk, whereas the type of confinement (p = 0.002; OR = 0.019) decreased it. Epidemiological surveillance of these neglected populations is lacking, highlighting the fact that STEC and S. enterica maintenance on BPS represents a potential threat to public health.

Horticulturae ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 68
Author(s):  
Yi-Ju Wang ◽  
Amanda J. Deering ◽  
Hye-Ji Kim

Our previous study reported that fresh produce grown in aquaponic and hydroponic systems can pose potential food safety hazards due to an accidental introduction of contaminated fish and cross-contamination between the systems. In this study, we examined the effects of plant species and age on the likelihood and level of internalization of Shiga toxin-producing Escherichia coli (STEC) in aquaponic and hydroponic systems. Four plant species, basil (Ocimum basilicum L. cv. Genovese), cilantro (Coriandrum Sativum L.), lettuce (Lactuca sativa cv. Cherokee), and kale (Brassica oleracea var. sabellica), received root damage treatment as seedlings before transplanting or mature plants at three weeks after transplanting by cutting off 1-cm tips of one-third of the roots. Enrichments and selective media were used for the isolation, and presumptive positive colonies were confirmed by PCR for the presence of stx1 gene in plant tissues, recirculating water, and fish feces collected at four weeks after transplanting. In hydroponic systems, STEC was found neither in the solution nor in the roots and leaves of all four plant species, possibly through improved sanitation and hygiene practices. However, consistent with our previous findings, STEC was found in the water, on the plant roots, and in the fish feces in aquaponic systems, even after thorough sanitation prior to the study. Regardless of plant age, STEC was internalized in the roots of all plant species when the roots were damaged, but there was no difference in the degree of internalization with STEC among plant species. STEC was present in the leaves only when seedlings received root damage treatment and were grown to maturity, indicating that root damage allows STEC to internalize in the roots within a week, but a longer period is required for STEC to internalize into the leaves. We concluded that root damage on seedlings can cause the internalization of E. coli O157:H7 in the edible parts of leafy vegetables and herbs in soilless production systems.


2019 ◽  
Vol 147 ◽  
Author(s):  
N. L. Adams ◽  
L. Byrne ◽  
T. C. Rose ◽  
G. K. Adak ◽  
C. Jenkins ◽  
...  

Abstract Shiga toxin-producing Escherichia coli (STEC) infection can cause serious illness including haemolytic uraemic syndrome. The role of socio-economic status (SES) in differential clinical presentation and exposure to potential risk factors amongst STEC cases has not previously been reported in England. We conducted an observational study using a dataset of all STEC cases identified in England, 2010–2015. Odds ratios for clinical characteristics of cases and foodborne, waterborne and environmental risk factors were estimated using logistic regression, stratified by SES, adjusting for baseline demographic factors. Incidence was higher in the highest SES group compared to the lowest (RR 1.54, 95% CI 1.19–2.00). Odds of Accident and Emergency attendance (OR 1.35, 95% CI 1.10–1.75) and hospitalisation (OR 1.71, 95% CI 1.36–2.15) because of illness were higher in the most disadvantaged compared to the least, suggesting potential lower ascertainment of milder cases or delayed care-seeking behaviour in disadvantaged groups. Advantaged individuals were significantly more likely to report salad/fruit/vegetable/herb consumption (OR 1.59, 95% CI 1.16–2.17), non-UK or UK travel (OR 1.76, 95% CI 1.40–2.27; OR 1.85, 95% CI 1.35–2.56) and environmental exposures (walking in a paddock, OR 1.82, 95% CI 1.22–2.70; soil contact, OR 1.52, 95% CI 2.13–1.09) suggesting other unmeasured risks, such as person-to-person transmission, could be more important in the most disadvantaged group.


2019 ◽  
Vol 24 (16) ◽  
Author(s):  
Juli Treacy ◽  
Claire Jenkins ◽  
Karthik Paranthaman ◽  
Frieda Jorgensen ◽  
Doris Mueller-Doblies ◽  
...  

An outbreak of Shiga toxin-producing Escherichia coli (STEC) O157:H7 occurred on the Isle of Wight between August and October 2017. Of the seven cases linked to the outbreak, five were identified through the statutory notification process and two were identified through national surveillance of whole genome sequencing data. Enhanced surveillance questionnaires established a common link to a farm, and link to the likely food vehicle, raw drinking milk (RDM). Microbiological investigations, including PCR, identified the presence of STEC O157:H7 in samples of RDM. Analysis of core genome single nucleotide polymorphism (SNP) data of STEC O157:H7 from human stool specimens, animal faecal samples and RDM demonstrated a one SNP difference between isolates, and therefore close genetic relatedness. Control measures that were put in place included suspension of sales and recall of RDM, as well as restrictions on public access to parts of the farm. Successful integration of traditional epidemiological surveillance and advanced laboratory methods for the detection and characterisation of STEC O157:H7 from human, animal and environmental samples enabled prompt identification of the outbreak vehicle and provided evidence to support the outbreak control team’s decision-making, leading to implementation of effective control measures in a timely manner.


2016 ◽  
Vol 237 ◽  
pp. 10-16 ◽  
Author(s):  
Rosa Guzman-Hernandez ◽  
Araceli Contreras-Rodriguez ◽  
Rosa Hernandez-Velez ◽  
Iza Perez-Martinez ◽  
Ahide Lopez-Merino ◽  
...  

2019 ◽  
Vol 12 (6) ◽  
pp. 884-889 ◽  
Author(s):  
Baha Abdalhamid ◽  
Emily L. Mccutchen ◽  
Alyssa C. Bouska ◽  
Zhang Weiwei ◽  
Brianna Loeck ◽  
...  

2019 ◽  
Vol 147 ◽  
Author(s):  
A. F. A. Pires ◽  
L. Patterson ◽  
E. A. Kukielka ◽  
P. Aminabadi ◽  
N. Navarro-Gonzalez ◽  
...  

Abstract Diversified farms are operations that raise a variety of crops and/or multiple species of livestock, with the goal of utilising the products of one for the growth of the other, thus fostering a sustainable cycle. This type of farming reflects consumers' increasing demand for sustainably produced, naturally raised or pasture-raised animal products that are commonly produced on diversified farms. The specific objectives of this study were to characterise diversified small-scale farms (DSSF) in California, estimate the prevalence of Salmonella enterica and Campylobacter spp. in livestock and poultry, and evaluate the association between farm- and sample-level risk factors and the prevalence of Campylobacter spp. on DSSF in California using a multilevel logistic model. Most participating farms were organic and raised more than one animal species. Overall Salmonella prevalence was 1.19% (95% confidence interval (CI95) 0.6–2), and overall Campylobacter spp. prevalence was 10.8% (CI95 = 9–12.9). Significant risk factors associated with Campylobacter spp. were farm size (odds ratio (OR)10–50 acres: less than 10 acres = 6, CI95 = 2.11–29.8), ownership of swine (OR = 9.3, CI95 = 3.4–38.8) and season (ORSpring: Coastal summer = 3.5, CI95 = 1.1–10.9; ORWinter: Coastal summer = 3.23, CI95 = 1.4–7.4). As the number of DSSF continues to grow, evaluating risk factors and management practices that are unique to these operations will help identify risk mitigation strategies and develop outreach materials to improve the food safety of animal and vegetable products produced on DSSF.


2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Jeremiah N. Ngugi ◽  
Eric M. Fèvre ◽  
Georgies F. Mgode ◽  
Mark Obonyo ◽  
Ginethon G. Mhamphi ◽  
...  

Abstract Background Leptospirosis is a neglected zoonosis of public health importance transmitted through contact with contaminated soil, water or urine of infected animals. In pigs the disease is characterized by abortion, still births and weak piglets. A cross-sectional study was conducted in May to July 2018 to estimate the sero-prevalence of leptospirosis and factors associated with seropositivity in slaughter pigs. A questionnaire was used to collect information on animal demographics. Serum was tested for anti-leptospiral antibodies using microscopic agglutination test (MAT) with a panel of 8 serovars. Sera were considered positive for sero-reactivity at a MAT titre ≥1:40 against at least one serovar. Chi-square tests were used to measure the strength of association between the MAT test result and exploratory variables. Results A total of 252 pig serum samples from seven slaughterhouses were tested for Leptospira antibodies by MAT. Of the 252 pigs sampled, 88.8% (244/252) were indigenous breeds; 55.6% (140/252) were female and 88.7% (220/252) were reared in extensive production systems. Eighty-three (32.9%; 83/252) sera samples tested positive on MAT against at least one serovar. Of the 8 serovars, the highest prevalence was recorded for serovar Lora 21.4% followed by Kenya 5.2%, Sokoine 3.6% and Grippotyphosa at 3.2%. Risk factors for leptospirosis seropositivity in pigs were: originating from farms with other types of livestock (OR 2.3; 95% CI 1.0–4.5) and mature pigs (OR 1.9; 95% CI 1.1–3.3). Conclusion This study demonstrates that there is a high prevalence of leptospirosis positive pigs at slaughter in a small-holder livestock keeping region of the Lake Victoria basin. The potential for cross species transmission of pathogenic serovars is highlighted as well as the potential for occupational exposure to slaughterhouse personnel. Improvements in husbandry practices (confinement and rodent control) and public health education among slaughterhouse workers and other high-risk groups is recommended.


Pathogens ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 124 ◽  
Author(s):  
Mthembu ◽  
Zishiri ◽  
Zowalaty

Livestock are an important source of protein and food for humans, however opportunistic pathogens such as Salmonella spp. turn livestock into vehicles of foodborne diseases. This study investigated the prevalence of virulence genes in Salmonella spp. isolated from livestock production systems in two provinces of South Africa. During the period from May to August, 2018, a total of 361 faecal (189), oral (100), environmental (soil (36) and water (27)) and feed (9) samples were randomly collected from different animals (cattle, sheep, goats, pigs, ducks and chickens) that were housed in small-scale livestock production systems from Eastern Cape and KwaZulu-Natal Provinces in South Africa. Salmonella spp. were isolated and identified using microbiological and DNA molecular methods. Salmonella spp. were present in 29.0% of the samples of which 30.2% belonged to the Salmonella enterica species as confirmed by the positive amplification of the species specific iroB gene. Virulence genes that were screened from livestock-associated Salmonella were invA, iroB, spiC, pipD and int1. Statistically significant associations (p < 0.05) were established between the virulence genes, sampling location, animal host as well as the season when samples were collected. Furthermore, statistically significant (p < 0.05) positive correlations were observed between most of the virulence genes investigated. This is one of the recent studies to detect and investigate livestock-associated Salmonella spp. in South Africa. This study highlights the importance of continuous monitoring and surveillance for pathogenic salmonellae. It also demonstrated the detection and prevalence of virulent Salmonella spp. harbored by livestock in South Africa. This study demonstrated the potential risks of pathogenic Salmonella enterica to cause foodborne diseases and zoonotic infections from farm-to-fork continuum using the global one-health approach.


Sign in / Sign up

Export Citation Format

Share Document