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Bacterial pathogens and resistance causing community acquired paediatric bloodstream infections in low- and middle-income countries: a systematic review and meta-analysis
Background
Despite a high mortality rate in childhood, there is limited evidence on the causes and outcomes of paediatric bloodstream infections from low- and middle-income countries (LMICs). We conducted a systematic review and meta-analysis to characterize the bacterial causes of paediatric bloodstream infections in LMICs and their resistance profile.
Methods
We searched Pubmed and Embase databases between January 1st 1990 and October 30th 2019, combining MeSH and free-text terms for “sepsis” and “low-middle-income countries” in children. Two reviewers screened articles and performed data extraction to identify studies investigating children (1 month-18 years), with at least one blood culture. The main outcomes of interests were the rate of positive blood cultures, the distribution of bacterial pathogens, the resistance patterns and the case-fatality rate. The proportions obtained from each study were pooled using the Freeman-Tukey double arcsine transformation, and a random-effect meta-analysis model was used.
Results
We identified 2403 eligible studies, 17 were included in the final review including 52,915 children (11 in Africa and 6 in Asia). The overall percentage of positive blood culture was 19.1% [95% CI: 12.0–27.5%]; 15.5% [8.4–24.4%] in Africa and 28.0% [13.2–45.8%] in Asia. A total of 4836 bacterial isolates were included in the studies; 2974 were Gram-negative (63.9% [52.2–74.9]) and 1858 were Gram-positive (35.8% [24.9–47.5]). In Asia, Salmonella typhi (26.2%) was the most commonly isolated pathogen, followed by Staphylococcus aureus (7.7%) whereas in Africa, S. aureus (17.8%) and Streptococcus pneumoniae (16.8%) were predominant followed by Escherichia coli (10.7%). S. aureus was more likely resistant to methicillin in Africa (29.5% vs. 7.9%), whereas E. coli was more frequently resistant to third-generation cephalosporins (31.2% vs. 21.2%), amikacin (29.6% vs. 0%) and ciprofloxacin (36.7% vs. 0%) in Asia. The overall estimate for case-fatality rate among 8 studies was 12.7% [6.6–20.2%]. Underlying conditions, such as malnutrition or HIV infection were assessed as a factor associated with bacteraemia in 4 studies each.
Conclusions
We observed a marked variation in pathogen distribution and their resistance profiles between Asia and Africa. Very limited data is available on underlying risk factors for bacteraemia, patterns of treatment of multidrug-resistant infections and predictors of adverse outcomes
Measuring antibiotic availability and use in 20 low- and middle-income countries
Objective To assess antibiotic availability and use in health facilities in low- and middle-income countries, using the service provision assessment and service availability and readiness assessment surveys.
Methods We obtained data on antibiotic availability at 13 561 health facilities in 13 service provision assessment and 8 service availability and readiness assessment surveys. In 10 service provision assessment surveys, child consultations with health-care providers were observed, giving data on antibiotic use in 22 699 children. Antibiotics were classified as access, watch or reserve, according to the World Health Organization’s AWaRe categories. The percentage of health-care facilities across countries with specific antibiotics available and the proportion of children receiving antibiotics for key clinical syndromes were estimated.
Findings The surveys assessed the availability of 27 antibiotics (19 access, 7 watch, 1 unclassified). Co-trimoxazole and metronidazole were most widely available, being in stock at 89.5% (interquartile range, IQR: 11.6%) and 87.1% (IQR: 15.9%) of health facilities, respectively. In contrast, 17 other access and watch antibiotics were stocked, by fewer than a median of 50% of facilities. Of the 22 699 children observed, 60.1% (13 638) were prescribed antibiotics (mostly co-trimoxazole or amoxicillin). Children with respiratory conditions were most often prescribed antibiotics (76.1%; 8972/11 796) followed by undifferentiated fever (50.1%; 760/1518), diarrhoea (45.7%; 1293/2832) and malaria (30.3%; 352/1160).
Conclusion Routine health facility surveys provided a valuable data source on the availability and use of antibiotics in low- and middle-income countries. Many access antibiotics were unavailable in a majority of most health-care facilities
New modelling technique for aperiodic-sampling linear systems
A general input-output modelling technique for aperiodic-sampling linear
systems has been developed. The procedure describes the dynamics of the system
and includes the sequence of sampling periods among the variables to be
handled. Some restrictive conditions on the sampling sequence are imposed in
order to guarantee the validity of the model. The particularization to the
periodic case represents an alternative to the classic methods of
discretization of continuous systems without using the Z-transform. This kind
of representation can be used largely for identification and control purposes.Comment: 19 pages, 0 figure
Systematic review of carbapenem-resistant Enterobacteriaceae causing neonatal sepsis in China.
BACKGROUND: Carbapenems are β-lactam antibiotics which are used to treat severe infections caused by multidrug resistant Enterobacteriacea. The recent emergence and rapid spread of Enterobacteriaceae resistant to carbapenems is a global concern. We undertook a systematic review of the antibiotic susceptibility and genotypic characteristics of carbapenem-resistant Enterobacteriaceae in Chinese neonates. METHODS: Systematic literature reviews were conducted (PubMed/Medline, Embase, Wanfang medical online databases, China National Knowledge Infrastructure (CNKI) database) regarding sepsis caused by carbapenem-resistant Enterobacteriaceae in Chinese neonates aged 0-30 days. RESULTS: 17 studies were identified. Eleven patients in the six studies reported the source of infection. Ten patients (10/11, 90.9%) were hospital-acquired infections. Genotypic data were available for 21 isolates in 11 studies (20 K. pneumoniae, 1 E. coli). NDM-1 was the most frequently reported carbapenem-resistant genotype (81.0%, 17/21). Carbapenem-resistant Klebsiella pneumoniae and Escherichia coli were resistant to many antibiotic classes with the exception of colistin and fosfomycin. Sequence type 105 (ST105) was the most commonly reported K. pneumoniae ST type (30.8%; 4/13), which was from the same hospital in Western China. ST17 and ST20 were the second and third most common K. pneumoniae ST type, 23.1% (3/13) and 15.4% (2/13) respectively. The three strains of ST17 are all from the same hospital in central China. The two strains of ST20, although not from the same hospital, belong to the eastern part of China. CONCLUSIONS: Klebsiella pneumoniae with the NDM-1 genotype was the leading cause of neonatal carbapenem resistant sepsis in China. Hospital acquired infection is the main source of carbapenem resistant sepsis. There is currently no licenced antibiotic regimen available to treat such an infection in China. Improved surveillance, controlling nosocomial infection and the rational use of antibiotics are the key factors to prevent and reduce its spread
Mortality Of The Veined Rapa Whelk, Rapana Venosa, In Relation To A Bloom Of Alexandrium Monilatum In The York River, United States
Veined rapa whelks (Rapana venosa), carnivorous marine gastropods experienced significant mortality during an Alexandrium monilatum bloom in the lower York River, VA in September 2007. Rapa whelks stopped feeding as dissolved oxygen and chlorophyll concentrations increased with the development of the bloom. Whelk mortality was preceded by external signs of stress including reduced ventilation, inability to attach to hard Substrates, periodic Pumping of the opercular plate, and increased mucus production over a period of 24-48 h prior to death. High concentrations (2-7 mu g g(-1) tissue) of goniodimum A, a toxin produced by A. monilatum, were observed in bivalves attached to the shells of rapa whelks. Concentrations of goniodimum A in whelk foot tissue ranged from 0.02-8.39 mu g g(-1). Mortality of rapa whelks was 100%. Mortality of oysters (Crassostrea virginica) and northern quahogs (Mercenaria mercenaria) in the same flow through system was 0%. The symptoms displayed by the rapa whelks in the 24-48 h prior to death were indicative of paralysis and followed a similar time Course documented for other molluscs exposed to toxic A. monilatum
Consumption of oral antibiotic formulations for young children according to the WHO Access, Watch, Reserve (AWaRe) antibiotic groups: an analysis of sales data from 70 middle-income and high-income countries
Background
The 2017 WHO Model List of Essential Medicines for Children (EMLc) groups antibiotics as Access, Watch, or Reserve, based on recommendations of their use as first-choice and second-choice empirical treatment for the most common infections. This grouping provides an opportunity to review country-level antibiotic consumption and a potential for stewardship. Therefore, we aimed to review 2015 levels of oral antibiotic consumption by young children globally.
Methods
We analysed wholesale antibiotic sales in 70 middle-income and high-income countries in 2015. We identified oral antibiotic formulations appropriate for use in young children (defined as child-appropriate formulations [CAFs]) using wholesale data from the IQVIA-Multinational Integrated Data Analysis System database, and we estimated 2015 antibiotic consumption in reference to the 2017 WHO EMLc Access, Watch, Reserve (AWaRe) antibiotic groups. We used three metrics for assessment of intra-country patterns: access percentage, defined as the number of CAF standard units of Access antibiotics divided by the total number of CAF standard units; amoxicillin index, defined as the number of amoxicillin CAF standard units divided by the total number of CAF standard units; and access-to-watch index, defined as the ratio of Access-to-Watch CAF standard units.
Findings
The overall median volume of CAF antibiotic standard units sold in 2015 per country was 74·5 million (IQR 12·4–210·7 million). The median access percentage among the 70 countries was 76·3% (IQR 62·6–84·2). The amoxicillin index was low (median 30·7%, IQR 14·3–47·3). The median access-to-watch index was 6·0 (IQR 3·1–9·8). CAF antibiotic consumption patterns were highly variable between the 70 countries, without a clear difference between high-income and middle-income countries.
Interpretation
Antibiotics in the Access group have a key role in treating young children globally. A simple combination of metrics based on the AWaRe groups can be informative on individual countries' patterns of antibiotic consumption and stewardship opportunities. These metrics could support countries in the development of programmes to improve access to core Access antibiotics, particularly amoxicillin.
Funding
Global Antibiotic R&D Partnership (German Federal Ministry of Health, Médecins Sans Frontières, Netherlands Ministry of Health, Welfare and Sport, and UK Department for International Development)
Nonmonotonic Friction due to Water Capillary Adhesion and Hydrogen Bonding at Multiasperity Interfaces
Global sales of oral antibiotics formulated for children.
Objective: To investigate international consumption patterns of child-appropriate oral formulations of antibiotics by formulation type, with a focus on dispersible tablets, using data from a global sales database. Method: Antibiotic sales data for 2015 covering 74 countries and regional country groups were obtained from the MIDAS® pharmaceutical sales database, which includes samples of pharmacy wholesalers and retailers. The focus was on sales of child-appropriate oral formulations of Access antibiotics in the 2017 World Health Organization's WHO Model list of essential medicines for children. Sales volumes are expressed using a standard unit (i.e. one tablet, capsule, ampoule or vial or 5 mL of liquid). Sales were analysed by antibiotic, WHO region and antibiotic formulation. Findings: Globally, 17.7 billion standard units of child-appropriate oral antibiotic formulations were sold in 2015, representing 24% of total antibiotic sales of 74.4 billion units (both oral and parenteral) in the database. The top five child-appropriate Access antibiotics by sales volume were amoxicillin, amoxicillin with clavulanic acid, trimethoprim-sulfamethoxazole, cefalexin and ampicillin. The proportion of the top five sold for use as a syrup varied between 42% and 99%. Dispersible tablets represented only 22% of all child-appropriate oral formulation sales and made up only 15% of sales of 10 selected Access antibiotics on the model list for children. Conclusion: Globally most child-appropriate oral antibiotics were not sold as dispersible tablets in 2015, as recommended by WHO. There is a clear need for novel solid forms of antibiotics suitable for use in children
Nonmonotonic Friction due to Water Capillary Adhesion and Hydrogen Bonding at Multiasperity Interfaces
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