Case-Control Study of Risk Factors for Sporadic Giardiasis and Parasite Assemblages in North West England

Giardia duodenalis is a major cause of infectious gastroenteritis worldwide, and it is diversified into eight genetic assemblages (A to H), which are distinguishable only by molecular typing. There is some evidence that the assemblages infecting humans (assemblages A and B) may have different transmission routes, but systematically acquired data, combining epidemiological and molecular findings, are required. We undertook a case-control study with Giardia genotyping in North West England, to determine general and parasite assemblage-specific risk factors. For people without a history of foreign travel, swimming in swimming pools and changing diapers were the most important risk factors for the disease. People infected with assemblage B reported a greater number of symptoms and higher frequencies of vomiting, abdominal pain, swollen stomach, and loss of appetite, compared with people infected with assemblage A. More importantly, keeping a dog was associated only with assemblage A infections, suggesting the presence of a potential zoonotic reservoir for this assemblage. This is the first case-control study to combine epidemiological data with Giardia genotyping, and it shows the importance of integrating these two levels of information for better understanding of the epidemiology of this pathogen

提高认识、明确目标推动生理学教学内容、手段和方法的改革

Reference sequences used for Giardia sub-assemblage identification. Sequences are indicated by their GenBank accession number followed by the host of origin. (XLSX 10 kb

Pharmacological Assessment of the Medicinal Potential of Acacia mearnsii De Wild.: Antimicrobial and Toxicity Activities

Acacia mearnsii De Wild. (Fabaceae) is a medicinal plant used in the treatment of microbial infections in South Africa without scientific validation of its bioactivity and toxicity. The antimicrobial activity of the crude acetone extract was evaluated by both agar diffusion and macrobroth dilution methods while its cytotoxicity effect was assessed with brine shrimp lethality assay. The study showed that both bacterial and fungal isolates were highly inhibited by the crude extract. The MIC values for the gram-positive bacteria (78.1–312.5) μg/mL, gram-negative bacteria (39.1–625) μg/mL and fungal isolates (625–5000) μg/mL differ significantly. The bacteria were more susceptible than the fungal strains tested. The antibiosis determination showed that the extract was more (75%) bactericidal than bacteriostatic (25%) and more fungicidal (66.67%) than fungistatic (33.33%). The cytotoxic activity of the extract was observed between 31.25 μg/mL and 500 μg/mL and the LC50 value (112.36 μg/mL) indicates that the extract was nontoxic in the brine shrimp lethality assay (LC50 > 100 μg/mL). These results support the use of A. mearnsii in traditional medicine for treatment of microbial infections. The extract exhibiting significant broad spectrum antimicrobial activity and nontoxic effects has potential to yield active antimicrobial compounds

Environmental Risk and Meningitis Epidemics in Africa

Epidemics of meningococcal meningitis occur in areas with particular environmental characteristics. We present evidence that the relationship between the environment and the location of these epidemics is quantifiable and propose a model based on environmental variables to identify regions at risk for meningitis epidemics. These findings, which have substantial implications for directing surveillance activities and health policy, provide a basis for monitoring the impact of climate variability and environmental change on epidemic occurrence in Africa

High metabolic potential may contribute to the success of ST131 uropathogenic Escherichia coli.

Uropathogenic Escherichia coli (UPEC) is the predominant cause of urinary tract infection in both hospital and community settings. The recent emergence of multidrug-resistant clones like the O25b:H4-ST131 lineage represents a significant threat to health, and numerous studies have explored the virulence potential of these organisms. Members of the ST131 clone have been described as having variable carriage of key virulence factors, and it has been suggested that additional unidentified factors contribute to virulence. Here we demonstrated that ST131 isolates have high metabolic potential and biochemical profiles that distinguish them from isolates of many other sequence types (STs). A collection of 300 UPEC isolates recovered in 2007 and 2009 in the Northwest region of England were subjected to metabolic profiling using the Vitek2 Advanced Expert System (AES). Of the 47 tests carried out, 30 gave a positive result with at least one of the 300 isolates examined. ST131 isolates demonstrated significant association with eight tests, including those for peptidase, decarboxylase, and alkalinization activity. Metabolic activity also correlated with antibiotic susceptibility profiles, with resistant organisms displaying the highest metabolic potential. This is the first comprehensive study of metabolic potential in the ST131 lineage, and we suggest that high metabolic potential may have contributed to the fitness of members of the ST131 clone, which are able to exploit the available nutrients in both the intestinal and urinary tract environments

Exposure, infection, systemic cytokine levels and antibody responses in young children concurrently exposed to schistosomiasis and malaria

Despite the overlapping distribution of Schistosoma haematobium and Plasmodium falciparum infections, few studies have investigated early immune responses to both parasites in young children resident in areas co-endemic for the parasites. This study measures infection levels of both parasites and relates them to exposure and immune responses in young children. Levels of IgM, IgE, IgG4 directed against schistosome cercariae, egg and adult worm and IgM, IgG directed against P. falciparum schizonts and the merozoite surface proteins 1 and 2 together with the cytokines IFN-γ, IL-4, IL-5, IL-10 and TNF-α were measured by ELISA in 95 Zimbabwean children aged 1–5 years. Schistosome infection prevalence was 14·7% and that of Plasmodium infection was 0% in the children. 43. 4% of the children showed immunological evidence of exposure to schistosome parasites and 13% showed immunological evidence of exposure to Plasmodium parasites. Schistosome–specific responses, indicative of exposure to parasite antigens, were positively associated with cercariae-specific IgE responses, while Plasmodium-specific responses, indicative of exposure to parasite antigens, were negatively associated with responses associated with protective immunity against Plasmodium. There was no significant association between schistosome-specific and Plasmodium-specific responses. Systemic cytokine levels rose with age as well as with schistosome infection and exposure. Overall the results show that (1) significantly more children are exposed to schistosome and Plasmodium infection than those currently infected and; (2) the development of protective acquired immunity commences in early childhood, although its effects on infection levels and pathology may take many years to become apparent

Clinical impact of double-faecal immunochemical testing following implementation into standard triage and investigation of primary care referrals in patients with lower gastrointestinal symptoms

BackgroundFaecal immunochemical testing has rapidly been established as the first-line triage for patients with symptoms suspicious for colorectal cancer. However, the reported low compliance of test returns issued from primary care is concerning. This article reports the real-world impact of implementation of a double-faecal immunochemical testing pathway for symptomatic referrals into routine clinical practice.MethodsAll eligible referrals between November 2021 and October 2022 were sent two faecal immunochemical tests via the faecal immunochemical testing interface office. Colorectal investigations were instigated if either test result was ≥10 µg haemoglobin per g. Referrals with double-negative results were reviewed by consultants who decided whether symptoms merited further investigation. Cancer registry follow-up data were cross-checked, and a further electronic registry allowed capture of re-referrals.ResultsSome 5425 patients were triaged using double-faecal immunochemical testing, with 5116 (94.3%) completing at least 1 and 4607 (84.9%) both faecal immunochemical tests. The positivity of one test was 20.8%, rising to 27.8% where both tests were completed. The number of referred patients undergoing colorectal investigation fell from 90% before faecal immunochemical testing-directed pathways to 56.6% owing to a reduction in investigating patients with double-negative results. The double-faecal immunochemical testing pathway had a sensitivity of 94.3% for the detection of colorectal cancer, with 37.5% of cancers with a negative first test being detected by the second. Only 3.3% of patients triaged through the double-faecal immunochemical testing pathway were re-referred.ConclusionThe double-faecal immunochemical testing pathway demonstrated high test return rates, a reduction in unnecessary investigations, and colorectal cancer detection rates similar to preimplementation rates

Malaria and helminth co-infections in outpatients of Alaba Kulito Health Center, southern Ethiopia: a cross sectional study

<p>Abstract</p> <p>Background</p> <p>Distribution of malaria and intestinal helminths is known to overlap in developing tropical countries of the world. Co-infections with helminth and malaria parasites cause a significant and additive problem against the host. The aim of this study was to asses the prevalence of malaria/helminth co-infection and the associated problems among febrile outpatients that attended Alaba Kulito Health Center, southern Ethiopia November and December 2007. A total of 1802 acute febrile patients were diagnosed for malaria. 458 Giemsa-stained thick and thin blood films were used for identification of <it>Plasmodium </it>species and Stool samples prepared using Kato-Katz technique were used to examine for intestinal helminths. Haemoglobin concentration was measured using a portable spectrophotometer (Hemocue HB 201). Anthropometry-based nutritional assessment of the study participants was done by measuring body weight to the nearest 0.1 kg and height to the nearest 0.1 cm.</p> <p>Findings</p> <p>458 of the total febrile patients were positive for malaria. Co infection with <it>Plasmodium </it>and helminth parasites is associated with significantly (p < 0.001) higher anaemia prevalence than single infection with <it>Plasmodium </it>parasites. And this difference was also significant for haemoglobin concentration (F = 10.18, p = 0.002), in which patients co infected with <it>Plasmodium </it>and helminth parasites showed lower mean haemoglobin concentration. More than one-third of the infected cases in both malaria infections and malaria/helminth co infections are undernourished. However the statistics for the difference is not significant.</p> <p>Conclusion</p> <p>Malaria and soil-transmitted helminthiasis obviously contribute to anaemia and low weight status and these conditions are more pronounced in individuals concurrently infected with malaria and soil-transmitted helminths. Hence, simultaneous combat against the two parasitic infections is very crucial to improve health of the affected communities.</p

Open label vancomycin in primary sclerosing cholangitis-inflammatory bowel disease:improved colonic disease activity and associations with changes in host-microbiome-metabolomic signatures

BACKGROUND: We conducted a single-arm interventional study, to explore mucosal changes associated with clinical remission under oral vancomycin (OV) treatment, in primary sclerosing cholangitis associated inflammatory bowel disease (PSC-IBD); NCT05376228.METHOD: Fifteen patients with PSC and active colitis (median faecal calprotectin 459µg/g; median total Mayo score 5) were treated with OV (125mg QID) for 4 weeks and followed-up for a further 4 weeks of treatment withdrawal (8 weeks, end-of-study). Colonic biopsies were obtained at baseline and week 4. Clinical assessments, and serum and stool samples (metagenomics, metatranscriptomics and metabolomics) were collected at weeks 0, 2, 4 and 8. The primary efficacy outcome measure was induction of clinical remission.RESULTS: OV resulted in clinical remission in 12/15 patients and significant reductions in faecal calprotectin. OV was associated with reduced abundances of Lachnospiraceae, genera Blautia and Bacteroides; and enrichment of Enterobacteriaceae, and genera Veillonella, Akkermansia and Escherichia. OV treatment was associated with downregulation of multiple metatranscriptomic pathways (including short chain fatty acid [SCFA] metabolism and bile acid [BA] biotransformation), along with host genes and multiple pathways involved in inflammatory responses and antimicrobial defence; and an upregulation of genes associated with extracellular matrix repair. OV use resulted in loss of specific faecal SCFAs and secondary BAs, including lithocholic acid derivatives. Colitis activity relapsed following OV withdrawal, with host mucosal and microbial changes trending towards baseline.CONCLUSION: Four weeks of OV induces remission in PSC-IBD activity, associated with a reduction in gut bacterial diversity and compositional changes relating to BA and SCFA homeostasis.</p