Subboiling Moist Heat Favors the Selection of Enteric Pathogen Clostridium difficile PCR Ribotype 078 Spores in Food

The effect of cold storage and cooking on the viability of Clostridioides difficile spores in consumer foods

The increased detection of clinical cases of Clostridioides difficile coupled with the persistence of clostridial spores at various stages along the food chain suggest that this pathogen may be foodborne. This study examined C. difficile (ribotypes 078 and 126) spore viability in chicken breast, beef steak, spinach leaves and cottage cheese during refrigerated (4 °C) and frozen (-20 °C) storage with and without a subsequent sous vide mild cooking (60 °C, 1 h). Spore inactivation at 80 °C in phosphate buffer solution, beef and chicken were also investigated to provide D_80°C values and determine if PBS was a suitable model system for real food matrices. There was no decrease in spore concentration after chilled or frozen storage and/or sous vide cooking at 60 °C. Non-log-linear thermal inactivation was observed for both C. difficile ribotypes at 80 °C in phosphate buffer solution (PBS), beef and chicken. The predicted PBS D_80°C values of 5.72±[2.90, 8.55] min and 7.50±[6.61, 8.39] min for RT078 and RT126, respectively, were in agreement with the food matrices D_80°C values of 5.65 min (95% CI range from 4.29 to 8.89 min) for RT078 and 7.35 min (95% CI range from 6.81 to 7.01 min) for RT126. It was concluded that C. difficile spores survive chilled and frozen storage and mild cooking at 60 °C but may be inactivated at 80 °C. Moreover thermal inactivation in PBS was representative of that observed in real food matrices (beef and chicken).

Chronic nasopharyngeal and otitis media tuberculosis: diagnosis and management difficulties

Nasopharyngeal and otitis media tuberculosis are rare extrapulmonary manifestations of Mycobacterium tuberculosis infection. We present a case of a middle-aged woman with manifestations of both conditions along with a description of the anatomical and temporal evolution of the disease. This case also highlights the difficulty of diagnosis and management of this condition, requiring a multidisciplinary approach. Extrapulmonary tuberculosis must be considered in the differential diagnosis of multiple head and neck conditions, including refractory chronic rhinosinusitis and otitis.

Late prosthetic shoulder joint infection due to Actinomyces neuii in an adult man

A 72-year-old man with a history of right reverse shoulder arthroplasty presented with a 1-month history of erythema, pain and drainage from the right shoulder. Arthrocentesis was performed and synovial fluid gram stain revealed gram-positive rods. Clinical diagnosis of prosthetic shoulder joint infection was made. Orthopaedic surgeons performed irrigation and debridement with resection of the right shoulder prothesis and implantation of an antimicrobial spacer. Operative cultures grew Actinomyces neuii The patient was treated with 6 weeks of ceftriaxone with improvement in both clinical symptoms and laboratory values. Actinomyces species remain a rare cause of late prosthetic joint infection (PJI) due to their slow growing and indolent course. While generalised actinomycosis is often treated with 6-12 months of antibiotics, the treatment course of Actinomyces PJI is not well characterised, with some sources suggesting a minimum of 6 weeks of antimicrobial therapy.

Global and Historical Distribution of Clostridioides difficile in the Human Diet (1981-2019): Systematic Review and Meta-Analysis of 21886 Samples Reveal Sources of Heterogeneity, High-Risk Foods, and Unexpected Higher Prevalence Toward the Tropic

Clostridioides difficile (CD) is a spore-forming bacterium that causes life-threatening intestinal infections in humans. Although formerly regarded as exclusively nosocomial, there is increasing genomic evidence that person-to-person transmission accounts for only <25% of cases, supporting the culture-based hypothesis that foods may be routine sources of CD-spore ingestion in humans. To synthesize the evidence on the risk of CD exposure via foods, we conducted a systematic review and meta-analysis of studies reporting the culture prevalence of CD in foods between January 1981 and November 2019. Meta-analyses, risk-ratio estimates, and meta-regression were used to estimate weighed-prevalence across studies and food types to identify laboratory and geographical sources of heterogeneity. In total, 21886 food samples were tested for CD between 1981 and 2019 (96.4%, n = 21084, 2007–2019; 232 food-sample-sets; 79 studies; 25 countries). Culture methodology, sample size and type, region, and latitude were sources of heterogeneity (p < 0.05). Although non-strictly-anaerobic methods were reported in some studies, and we confirmed experimentally that improper anaerobiosis of media/sample-handling affects CD recovery in agar (Fisher, p < 0.01), most studies (>72%) employed the same (one-of-six) culture strategy. Because the prevalence was also meta-analytically similar across six culture strategies reported, all studies were integrated using three meta-analytical methods. At the study level (n = 79), the four-decade global cumulative-prevalence of CD in the human diet was 4.1% (95%CI = −3.71, 11.91). At the food-set level (n = 232, mean 12.9 g/sample, similar across regions p > 0.2; 95%CI = 9.7–16.2), the weighted prevalence ranged between 4.5% (95%CI = 3–6%; all studies) and 8% (95%CI = 7–8%; only CD-positive-studies). Risk-ratio ranking and meta-regression showed that milk was the least likely source of CD, while seafood, leafy green vegetables, pork, and poultry carried higher risks (p < 0.05). Across regions, the risk of CD in foods for foodborne exposure reproducibly decreased with Earth latitude (p < 0.001). In conclusion, CD in the human diet is a global non-random-source of foodborne exposure that occurs independently of laboratory culture methods, across regions, and at a variable level depending on food type and latitude. The latitudinal trend (high CD-food-prevalence toward tropic) is unexpectedly inverse to the epidemiological observations of CD-infections in humans (frequent in temperate regions). Findings suggest the plausible hypothesis that ecologically-richer microbiomes in the tropic might protect against intestinal CD colonization/infections despite CD ingestion.

ABO blood groups and hepatitis B virus infection: a systematic review and meta-analysis

OBJECTIVE

Hepatitis B virus (HBV) infection is a major public health problem worldwide. Several studies have reported that ABO blood groups may be associated with HBV infection. However, its association is still controversial. We performed a meta-analysis to investigate whether ABO blood groups were associated with HBV infection.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Relevant studies available before 1 December 2019 were identified by searching PubMed, EMBASE, Web of Science, ScienceDirect and the Cochrane Library.

ELIGIBILITY CRITERIA

All cross-sectional or cohort studies from which the data of ABO blood group distribution and HBV infection could be extracted.

DATA EXTRACTION AND SYNTHESIS

Studies were identified and extracted by two reviewers independently. Risk ratios (RRs) and 95% CIs were pooled by random-effect models to quantify this association.

RESULTS

Thirty-eight eligible articles including 241 868 HBV-infected subjects and 6 487 481 uninfected subjects were included. Overall, the risk of HBV infection had decreased by 8% in subjects with blood group B when compared with non-B blood group (RR=0.92, 95% CI 0.86 to 0.98). In the subgroup analyses, the inverse relationship between blood group B and HBV infection remained stable in higher endemic areas (HBV prevalence ≥5%), Asian people, larger sample size studies (≥2000), general population and blood donors, lower middle income group and studies published before the year 2010. Additionally, subjects with blood group O had a 12% increased risk of HBV infection (RR=1.12, 95% CI 1.01 to 1.24) in higher endemic areas. In the sensitivity analysis, the pooled risk estimates of blood group B and HBV infection were still stable.

CONCLUSIONS

Our data suggested that the blood group B was associated with a lower risk of HBV infection. More research is needed to clarify the precise role of the ABO blood group in HBV infection to address the global question of HBV infection.

Genomic Delineation of Zoonotic Origins of Clostridium difficile

Clostridium difficile is toxin-producing antimicrobial resistant (AMR) enteropathogen historically associated with diarrhea and pseudomembranous colitis in hospitalized patients. In recent years, there have been dramatic increases in the incidence and severity of C. difficile infection (CDI), and associated morbidity and mortality, in both healthcare and community settings. C. difficile is an ancient and diverse species that displays a sympatric lifestyle, establishing itself in a range of ecological niches external to the healthcare system. These sources/reservoirs include food, water, soil, and over a dozen animal species, in particular, livestock such as pigs and cattle. In a manner analogous to human infection, excessive antimicrobial exposure, particularly to cephalosporins, is driving the expansion of C. difficile in livestock populations worldwide. Subsequent spore contamination of meat, vegetables grown in soil containing animal feces, agricultural by-products such as compost and manure, and the environment in general (households, lawns, and public spaces) is contributing to a persistent community source/reservoir of C. difficile and the insidious rise of CDI in the community. The whole-genome sequencing era continues to redefine our view of this complex pathogen. The application of high-resolution microbial genomics in a One Health framework (encompassing clinical, veterinary, and environment derived datasets) is the optimal paradigm for advancing our understanding of CDI in humans and animals. This approach has begun to yield critical insights into the genetic diversity, evolution, AMR, and zoonotic potential of C. difficile. In Europe, North America, and Australia, microevolutionary analysis of the C. difficile core genome shows strains common to humans and animals (livestock or companion animals) do not form distinct populations but share a recent evolutionary history. Moreover, for C. difficile sequence type 11 and PCR ribotypes 078 and 014, major lineages of One Health importance, this approach has substantiated inter-species clonal transmission between animals and humans. These findings indicate either a zoonosis or anthroponosis. Moreover, they challenge the existing paradigm and the long-held misconception that CDI is primarily a healthcare-associated infection. In this article, evolutionary, and zoonotic aspects of CDI are discussed, including the anthropomorphic factors that contribute to the spread of C. difficile from the farm to the community.

Complete Genome Sequences of Historic Clostridioides difficile Food-Dwelling Ribotype 078 Strains in Canada Identical to That of the Historic Human Clinical Strain M120 in the United Kingdom

Clostridioides (Clostridium) difficile is a spore-forming anaerobic bacterium that causes severe intestinal diseases in humans. Here, we report the complete genome sequence of the first C. difficile foodborne type strain (PCR ribotype 078) isolated from food animals in Canada in 2004, which has 100% similarity to the genome sequence of the historic human clinical strain M120.

Clostridioides (Clostridium) difficile is a spore-forming anaerobic bacterium that causes severe intestinal diseases in humans. Here, we report the complete genome sequence of the first C. difficile foodborne type strain (PCR ribotype 078) isolated from food animals in Canada in 2004, which has 100% similarity to the genome sequence of the historic human clinical strain M120.

Clostridium difficile colitis and zoonotic origins-a narrative review

Clostridium difficile is a major cause of hospital-associated diarrhoea, and in severe cases leads to pseudomembranous colitis and toxic megacolon. The frequency of C. difficile infection (CDI) has increased in recent decades, with 453 000 cases identified in 2011 in the USA. This is related to antibiotic-selection pressure, disruption of normal host intestinal microbiota and emergence of antibiotic-resistant C. difficile strains. The burden of community-acquired CDI has been increasingly appreciated, with disease identified in patients previously considered low-risk, such as young women or patients with no prior antibiotic exposure. C. difficile has been identified in livestock animals, meat products, seafood and salads. It has been postulated that the pool of C. difficile in the agricultural industry may contribute to human CDI. There is widespread environmental dispersal of C. difficile spores. Domestic households, turf lawns and public spaces are extensively contaminated, providing a potential reservoir for community-acquired CDI. In Australia, this is particularly associated with porcine-derived C. difficile UK PCR ribotype 014/020. In this article, the epidemiological differences between hospital- and community-acquired CDI are discussed, including some emerging evidence for community-acquired CDI being a possible zoonosis.