Systematic review of the global epidemiology, clinical and laboratory profile of enteric fever

Background: Children suffer the highest burden of enteric fever among populations in South Asian countries. The clinical features are non-specific, vary in populations, and are often difficult to distinguish clinically from other febrile illnesses, leading to delayed or inappropriate diagnosis and treatment. We undertook a systematic review to assess the clinical profile and laboratory features of enteric fever across age groups, economic regions, level of care and antibiotic susceptibility patterns.Methods: We searched PubMed (January 1964-December 2013) for studies describing clinical features in defined cohorts of patients over varying time periods. Studies with all culture-confirmed cases or those with at least 50% culture-confirmed cases were included. 242 reports were screened out of 4398 relevant articles and 180 reports were included for final review.Results: 96% of studies were from an urban location, 96% were hospital-based studies, with 41% of studies were from South Asia. Common clinical features in hospitalized children include high-grade fever, coated tongue, anaemia, nausea/vomiting, diarrhea, constipation, hepatomegaly, splenomegaly neutrophilia, abdominal distension and GI bleeding. In adults\u27 nausea/vomiting, thrombocytopenia and GI perforation predominate. The case-fatality rate in children under 5 years is higher than school aged children and adolescents, and is highest in Sub Saharan Africa and North Africa/Middle East regions. Multi-drug resistant enteric fever has higher rates of complications than drug sensitive enteric fever, but case fatality rates were comparable in both.CONCLUSIONS: Our findings indicate variability in disease presentation in adults compared to children, in different regions and in resistant vs sensitive cases. Majority of studies are from hospitalized cases, and are not disaggregated by age. Despite higher complications in MDR enteric fever, case fatality rate is comparable to sensitive cases, with an overall hospital based CFR of 2%, which is similar to recent global estimates. This review underscores the importance of further epidemiological studies in community settings among children and adults, and the need for further preventable measures to curtail the burden of disease

A comparison of fluoroquinolones versus other antibiotics for treating enteric fever: meta-analysis

Objectives To review evidence supporting use of fluoroquinolones as first line agents over other antibiotics for treating typhoid and paratyphoid fever (enteric fever)

Challenges in measuring complications and death due to invasive Salmonella infections

Despite the highest burden of Typhoid fever in children globally, exact estimates of morbidity and mortality are lacking due to scarcity of published data. Despite a high prevalence and a socioeconomic burden in developing countries, published data with morbidity and mortality figures are limited especially Africa and South American regions. Data from the community is insufficient and most case fatality estimates are extrapolations from hospital based studies that do not cover all geographical regions, and include cases which may or not be culture confirmed, MDR resistant or sensitive cases, or from mixed populations of age (adults and children). Complications of typhoid such as intestinal perforation, bone marrow suppression, and encephalopathy are dependent on MDR/Fluoroquinolone resistant Salmonella infection, comorbidities such as malnutrition, and health-care access. Data is again insufficient to estimate the true burden of Typhoid Fever in different regions and groups of populations. Although there has been a rapid decline in cases in developed countries with the advent of improved sanitization, timely and easy access to health care and laboratories, this is still not the case in the developing countries where Typhoid deaths are still occurring. The way forward is to develop rapid and cost effective point of care diagnostic tests, put in place validated clinical algorithms for suspected clinical cases, and design prospective, and community based studies in different groups, implement maintenance of electronic health records in large public sector hospitals and regions to identify populations that will benefit most from the implementation of vaccine. Policies on public health education and typhoid vaccine may help to reduce morbidity and mortality due to the disease

Biochar-based geopolymer nanocomposite for COD and phenol removal from agro-industrial biorefinery wastewater : kinetic modelling, microbial community, and optimization by response surface methodology

Agro-industrial biorefinery effluent (AIBW) is considered a highly polluting source responsible for environmental contamination. It contains high loads of chemical oxygen demand (COD), and phenol, with several other organic and inorganic constituents. Thus, an economic treatment approach is required for the sustainable discharge of the effluent. The long-term process performance, contaminant removal and microbial response of AIBW to rice straw-based biochar (RSB) and biochar-based geopolymer nanocomposite (BGC) as biosorbents in an activated sludge process were investigated. The adsorbents operated in an extended aeration system with a varied hydraulic retention time of between 0.5 and 1.5 d and an AIBW concentration of 40–100% for COD and phenol removal under standard conditions. Response surface methodology was utilised to optimize the process variables of the bioreactor system. Process results indicated a significant reduction of COD (79.51%, 98.01%) and phenol (61.94%, 74.44%) for BEAS and GEAS bioreactors respectively, at 1 d HRT and AIBW of 70%. Kinetic model analysis indicated that the Stover-Kincannon model best describes the system functionality, while the Grau model was better in predicting substrate removal rate and both with a precision of between R 2 (0.9008–0.9988). Microbial communities examined indicated the abundance of genera, following the biosorbent addition, while RSB and BGC had no negative effect on the bioreactor's performance and bacterial community structure of biomass. Proteobacteria and Bacteroidetes were abundant in BEAS. While the GEAS achieved higher COD and phenol removal due to high Nitrosomonas, Nitrospira, Comamonas, Methanomethylovorans and Acinetobacter abundance in the activated sludge. Thus, this study demonstrated that the combination of biosorption and activated sludge processes could be promising, highly efficient, and most economical for AIBW treatment, without jeopardising the elimination of pollutants or the development of microbial communities

Parametric optimization and kinetic modelling for organic matter removal from agro-waste derived paper packaging biorefinery wastewater

The state-of-the-art paper packaging biorefinery utilizes cellulose fibrous material from paddy straw and papaya latex to produce packaging products. This in turn generate wastewater with high organic matter content that if disposed without treatment will pollute water bodies and affect aquatic life below water. Therefore, to comply with "clean water and sanitation" (SDG 6) and "life below water" (SDG 14), this study assesses the efficacy of an extended aeration activated sludge (EAAS) in the treatment of paper packaging biorefinery wastewater (PPBW) by employing paddy straw-derived activated carbon as a biosorbent. Findings revealed that the system was able to achieve 95–98.2% and 90.62–94.96% biological oxygen demand (BOD 5 ) and chemical oxygen demand (COD) reduction, respectively. The maximum organic matter removals were achieved at 2-day hydraulic retention time (HRT) and 60% PPBW concentration. To evaluate substrate removal rates, the first-order, modified Stover–Kincannon and Grau second-order models were used. In the modified Stover–Kincannon model, high correlation coefficients values R2 of 0.99986 and 0.99991 were obtained for COD and BOD 5 , respectively. Twenty grams COD/L/day and 50 gBOD 5 /L/day were obtained as Umsr for COD and BOD 5 , respectively, and 20.402 g/L/day and 56.295 g/L/day as K V constants for COD and BOD 5 , respectively. The COD and BOD 5 biokinetic constant values for the Grau second-order organic matter removal rate constant kS were 36 day −1 and 0.78 day −1 , respectively. Here, 0.9989 and 0.99928 were the obtained R2 values for COD and BOD 5 , respectively. The EAAS bioreactor system described by modified Stover–Kincannon model was proven to best suit the experimental data. Therefore, the model can be used in designing an EAAS system and consequently predict the bioreactor behaviour. The result of this study provided a benchmark for the actual implementation of PSAC in PPBW treatment for COD and BOD 5 removal. It has been proven that PSAC biosorbent sourced from a natural agro-waste material is essential and could be used as an efficient substance for organic matter removal. Operating expenses and associated savings were such that PASC was more attractive in an economic analysis of wastewater treatment demands. It is environmentally benign and offers a green treatment option to the PPBW. It could be an alternative to chemical materials because it is harmless to human health and proffer sustainable solution to potable water production