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Trace metals and metalloids are groups of chemical elements that naturally occur in low concentrations and cycle in the environment driven by natural processes and human activities. They have a persistent and bio-accumulative tendency in the environment, and certain trace metals and metalloids have become a public health concern. This study assesses the concentration of eleven trace metals and a metalloid in sediments and catfish muscle from five study sites in the Eastern Tanzanian River basin. Forty catfish tissues and fifteen sediment samples were collected and analyzed using ICP-MS. Concentrations of As, Cd, Co, Pb, and Zn did not exceed the United States Environmental Protection Agency (USEPA) guideline for pollution of sediments, while Al Cr, Al, Mn, and V with values ranging from (118.54 to 70154.55) indicating moderately polluted. The stations Java-Sadaani and Matandu showed the highest Cr, Ni, and Cu concentrations, but the potential ecological risk index (RI) was low (RI < 95). In the catfish muscle tissue, the levels of Cd, Pb, Cu, and Zn did not surpass the EU and FAO/WHO limits and results ranged from 2.22 to 35.22mg/kg. Low levels of accumulation of Cd, Pb, and As were found in this study compared to catfish muscles from other studies, whereas the concentrations of other trace metals and metalloids analyzed had comparable results. Biota/sediment accumulation factors (BSAF) were all < 1. The weekly metal intake (MWI) results ranged from 6.89E-04 to 2.43E+01 μg/know-1week-1, indicating a low risk as the value did not exceed the FAO/WHO established Permissible Tolerable Weekly Intake (PTWI). The non-carcinogenic health risk result THQ was 4.43E-02 and the carcinogenic health risks result HI was 4.42E-05 which indicated tolerable levels of risks as both the values of the Target Hazard Quotient (THQ) and the Hazard Index (HI) was < 1, and the carcinogenic target risk (TR) is < 0.0001. The highest TR values were observed for Cr and Ni. We recommend a continued monitoring of the changes in trace metal levels in the environment and biota together with continuous public health education on the dangers of high levels of trace metals. [ABSTRACT FROM AUTHOR]

Introduction: Salmonella is one of the most common causes of food-borne outbreaks and infection worldwide. Non-typhoid Salmonella (NTS) infections are common and remain a significant public health problem among important bacterial foodborne diseases. The current study aimed to establish the Non typhoid Salmonella infection and antimicrobial resistance status among selected patients at Morogoro Regional Referral Hospital (MRRH), Morogoro Region, Tanzania, to inform clinical care management and public health interventions. Methodology: A cross-sectional study was conducted using medical records and samples were collected from hospitalised and outpatients between October and December 2021. A total of 153 participants were enrolled in the study and 132 consented to being sampled. The collected samples were analysed using standard microbiological techniques. The isolates were subjected to molecular genotyping, where Polymerase Chain Reaction (PCR) was performed targeting the 16S rDNA gene. PCR products were then submitted for sequencing to establish phylogenetic relatedness. Results: The phylogenetic analysis identified two Salmonella serovars; Salmonella Enteritidis and Salmonella Typhimurium. The isolates were from four adults and seven children patients. The isolates were tested against six antimicrobial agents: tetracycline, trimethoprim, gentamycin, ciprofloxacin, ampicillin and cefotaxime. Further antimicrobial assays were performed by screening 10 antimicrobial resistance genes using PCR. Overall, the highest resistance was observed in ampicillin (100%), whereas the lowest resistance was recorded for ciprofloxacin and gentamicin (9.1%). In addition, four (36.4%) of the isolates were resistant to cefotaxime and three (27.3%) to tetracycline and trimethoprim. The isolates also exhibit the presence of resistance genes for sulfamethoxazole 1&2, tetracycline (tet) A&B, Beta-lactamaseCTXM, Beta-lactamaseTEM, Beta-lactamaseSHV, Gentamycine, Acra and acc3-1 in different occurrences. In conclusion, the overall prevalence of Salmonella species in Morogoro region was 8.3% (11/132) with Salmonella Enteritidis and Salmonella Typhimurium being the only serovars detected from adults and children stool samples. Conclusion: Our investigation showed that both children and adults had been exposed to Salmonella spp. However, the occurrence of NTS was higher in children (5.3% (7/132) compared to adults (3.0% (4/132). To stop zoonotic infections and the development of antimicrobial resistance in the community, this calls for Infection Prevention and Control (IPC) and stewardship programmes on rational use of antimicrobials in both health facilities and at the community level. Author summary: Typhoid fever is claimed to prevail in Morogoro region. Most patients with stomach pain and or diarrhoea go for a diagnosis of typhoid despite the existence of other etiological agents causing the same clinical signs. Sample culture and isolation of bacteria have been a gold-standard method for the detection of disease-causing agents. However, this approach is rarely made by most hospitals, with the exception of regional and district hospitals in the public sector and big hospitals in the private sector. They always rely on the widal test, which suffers from significant limitations in its sensitivity and specificity. It is, therefore, difficult to identify appropriate etiological agents and assess their susceptibility to antimicrobials. Because of that, the contribution of non-typhoid salmonellosis is not featured. The authors have assessed the occurrence of non-typhoid Salmonella in hospitalized and outpatients of all age groups at Morogoro Regional Hospital as a modal to establish its contribution to gastrointestinal infections in the region through both conventional and molecular approaches. It was observed that the infection rate was high in children, and the no-typhoid Salmonella serovars had considerable resistance to the commonly used antimicrobial. This calls for further surveillance of these neglected non-typhoid salmonella in clinical settings [ABSTRACT FROM AUTHOR]

This systematic review describes what "the cutting edge vaccines for Aeromonas hydrophila are". The focus is on types of high tech biotechnological based vaccines, target gene or antigen in developing these vaccines, and challenge model fish species used in vaccines efficacy testing. Vaccines delivery methods, immune response, and their efficacy, adjuvant or carrier systems used, and the overall experimental setup or design of the vaccines under investigation are also described. The search for the original papers published between 2009 and 2018 was conducted in June of 2018, using the PubMed and Google scholar electronic database. Twenty-three (23/4386) studies were included in the final assembly using PRISMA guidelines (Protocol not registered). Recombinant protein vaccines were the highly experimented type of the modern biotechnological based vaccines identified in the selected studies (16/23; 70%). Outer membrane proteins (OMPs) of different β-barrels were shown to be a potential antigenic entity for A. hydrophila vaccines (57%). Intraperitoneal route with conventional carries or adjuvants was the highly applied delivery system while very few studies used herbal based vaccine adjuvants and nanomaterial as a vaccine carrier. Variation was observed in terms of protection levels in the selected studies. The experimental designs partly contributed to the observed variation. Therefore, recombinant vaccines that use new carrier system technologies and delivered through oral route in feeds would have been of great value for use in the prevention and control of A. hydrophila infections in fish. Despite the usefulness as academic tools to identify what is important in pathogenicity of the etiological agent to the host fish, these vaccines are only economically viable in very high-value animals. Therefore, if vaccination is a good option for A. hydrophila group, then simple autogenous vaccines based on accurate typing and evidence-based definition of the epidemiological unit for their use would be the most viable approach in terms of both efficacy and economic feasibility especially in low and middle-income countries (LMIC). [ABSTRACT FROM AUTHOR]