Epidemiology of post-neonatal bacterial meningitis in Cape Town children

CITATION: Hussey, G. 1997. Epidemiology of post-neonatal bacterial meningitis in Cape Town children. South African Medical Journal, 87(1):51-56.The original publication is available at http://www.samj.org.zaBacterial meningitis is a major cause of childhood morbidity and mortality in South Africa. However, comprehensive regional or national epidemiological data, essential for rational public health interventions, are lacking. The purpose of this 1-year prospective study, from 1 August 1991 to 31 July 1992, was to define the magnitude of the problem of childhood bacterial meningitis in Cape Town. The study group consisted of all children, aged > 1 month to < 74 years, who presented with proven bacterial meningitis at all the hospitals in the Cape Town metropolitan area. During the year 201 cases were identified: 101 (50.2%) were due to Neisseria meningitidis, 74 (36.8%) were due to Haemophilus influenzae and 26 (12.9%) were due to Streptococcus pneumoniae. The overall incidence rate (95% confidence interval) for children less than 14 years, 5 years and 1 year was 34 (30 - 40), 76 (65 - 88) and 257 (213 - 309) per 100 000 children, respectively. The rate was highest in black infants, 416 (316 - 545)/100 000. This was 2 times greater than the rate in coloured infants and about 4.5 times greater than the rate in white infants. The median age of all the children was 10 months. The ages of children with haemophilus and pneumococcal meningitis were similar, 9 and 7.5 months respectively (P = 0.43), while children with meningococcal meningitis were significantly cider (22 months) than the others (P < 0.01). The overall case fatality rate was 5%, and 12.9% of survivors had significant neurological sequelae (disability) on discharge.Publisher’s versio

The role of epidemic resistance plasmids and international high-risk clones in the spread of multidrug-resistant Enterobacteriaceae

Escherichia coli ST131and Klebsiella pneumoniae ST258 emerged in the 2000s as important human pathogens; have spread extensively throughout the world and are responsible for the rapid increase in antimicrobial resistance among E. coli and K. pneumoniae respectively. E. coli ST131 causes extra-intestinal infections, is often fluoroquinolone resistant and associated with Extend-spectrum β-lactamase production especially CTX-M-15. K. pneumoniae ST258 causes urinary and respiratory tract infections and is associated with carbapenemases most often KPC-2 and KPC-3. The most prevalent lineage within ST131 is named fimH30 because it contains the 2 H30 variant of the type 1 fimbrial adhesin gene and recent molecular studies have demonstrated that this lineage emerged in early 2000‟s and was then followed by the rapid expansion of its sublineages H30-R and H30-Rx. K. pneumoniae ST258 comprises of 2 distinct lineages namely clade I and clade II. Moreover, it seems that ST258 is a hybrid clone that was created by a large recombination event between ST11 and ST442. Epidemic plasmids with blaCTX-M and blaKPC belonging to the incompatiblity group F have contributed significantly to the success of these clones. E. coli ST131 and K. pneumoniae ST258 are the quintessential examples of international multidrug-resistant high risk clones.In part by a research grant from the Calgary Laboratory Services (#10006465).http://cmr.asm.orghb201

Coordinated Cluster/Double Star Observations of Dayside Reconnection Signatures

The recent launch of the equatorial spacecraft of the Double Star mission, TC-1, has provided an unprecedented opportunity to monitor the southern hemisphere dayside magnetopause boundary layer in conjunction with northern hemisphere observations by the quartet of Cluster spacecraft. We present first results of one such situation where, on 6 April 2004, both Cluster and the Double Star TC-1 spacecraft were on outbound transits through the dawnside magnetosphere. The observations are consistent with ongoing reconnection on the dayside magnetopause, resulting in a series of flux transfer events (FTEs) seen both at Cluster and TC-1, which appear to lie north and south of the reconnection line, respectively. In fact, the observed polarity and motion of each FTE signature advocates the existence of an active reconnection region consistently located between the positions of Cluster and TC-1, with Cluster observing northward moving FTEs with +/− polarity, whereas TC-1 sees −/+ polarity FTEs. This assertion is further supported by the application of a model designed to track flux tube motion for the prevailing interplanetary conditions. The results from this model show, in addition, that the low-latitude FTE dynamics are sensitive to changes in convected upstream conditions. In particular, changing the interplanetary magnetic field (IMF) clock angle in the model suggests that TC-1 should miss the resulting FTEs more often than Cluster and this is borne out by the observations

ESR and EISCAT observations of the response of the cusp and cleft to IMF orientation changes

International audienceWe report observations of the cusp/cleft ionosphere made on December 16th 1998 by the EISCAT (European incoherent scatter) VHF radar at Tromsø and the EISCAT Svalbard radar (ESR). We compare them with observations of the dayside auroral luminosity, as seen by meridian scanning photometers at Ny Ålesund and of HF radar backscatter, as observed by the CUTLASS radar. We study the response to an interval of about one hour when the interplanetary magnetic field (IMF), monitored by the WIND and ACE spacecraft, was southward. The cusp/cleft aurora is shown to correspond to a spatially extended region of elevated electron temperatures in the VHF radar data. Initial conditions were characterised by a northward-directed IMF and cusp/cleft aurora poleward of the ESR. A strong southward turning then occurred, causing an equatorward motion of the cusp/cleft aurora. Within the equatorward expanding, southward-IMF cusp/cleft, the ESR observed structured and elevated plasma densities and ion and electron temperatures. Cleft ion fountain upflows were seen in association with elevated ion temperatures and rapid eastward convection, consistent with the magnetic curvature force on newly opened field lines for the observed negative IMF By. Subsequently, the ESR beam remained immediately poleward of the main cusp/cleft and a sequence of poleward-moving auroral transients passed over it. After the last of these, the ESR was in the polar cap and the radar observations were characterised by extremely low ionospheric densities and downward field-aligned flows. The IMF then turned northward again and the auroral oval contracted such that the ESR moved back into the cusp/cleft region. For the poleward-retreating, northward-IMF cusp/cleft, the convection flows were slower, upflows were weaker and the electron density and temperature enhancements were less structured. Following the northward turning, the bands of high electron temperature and cusp/cleft aurora bifurcated, consistent with both subsolar and lobe reconnection taking place simultaneously. The present paper describes the large-scale behaviour of the ionosphere during this interval, as observed by a powerful combination of instruments. Two companion papers, by Lockwood et al. (2000) and Thorolfsson et al. (2000), both in this issue, describe the detailed behaviour of the poleward-moving transients observed during the interval of southward Bz, and explain their morphology in the context of previous theoretical work

The effect of electromagnetic radiation in the mobile phone range on the behaviour of the rat

Abstract Electromagnetic radiation (EMR) is emitted from electromagnetic fields that surround power lines, household appliances and mobile phones. Research has shown that there are connections between EMR exposure and cancer and also that exposure to EMR may result in structural damage to neurons. In a study by Salford et al. (Environ Health Perspect 111:881-883, 2003) the authors demonstrated the presence of strongly stained areas in the brains of rats that were exposed to mobile phone EMR. These darker neurons were particularly prevalent in the hippocampal area of the brain. The aim of our study was to further investigate the effects of EMR. Since the hippocampus is involved in learning and memory and emotional states, we hypothesised that EMR will have a negative impact on the subject&apos;s mood and ability to learn. We subsequently performed behavioural, histological and biochemical tests on exposed and unexposed male and female rats to determine the effects of EMR on learning and memory, emotional states and corticosterone levels. We found no significant differences in the spatial memory test, and morphological assessment of the brain also yielded non-significant differences between the groups. However, in some exposed animals there were decreased locomotor activity, increased grooming and a tendency of increased basal corticosterone levels. These findings suggested that EMR exposure may lead to abnormal brain functioning

Colistin non-susceptible Pseudomonas aeruginosa ST654 with blaNDM-1 arrives in North America

This study describes 3 different blaNDM-1 genetic platforms in 3 different species obtained from the same patient who was directly transferred to an institution in Calgary, Canada, following a prolonged hospital stay in India. The blaNDM-1 in the Escherichia coli was located on a 176kb IncA/C plasmid contained within an ISCR1 region. The blaNDM-1 in the Providencia rettgeri was located on a 117kb IncT plasmid contained within Tn3000, while the blaNDM-1 in Pseudomonas aeruginosa was located on the chromosome within an ISCR3 region. This report highlights the plasticity of the genetic regions and environments associated with blaNDM-1. To the best of our knowledge, this is the first report of P. aeruginosa with blaNDM-1 identified in North America and the first report of blaOXA-181in P. rettgeri. The P. aeruginosa belonged to the international high risk clone ST654 and was non-susceptible to colistin. This case emphasizes the need for appropriate infection prevention and control measures and vigilant screening for carbapenem resistant Gram negative bacteria in patients with a history of travel to endemic areas, such as the Indian subcontinent.In part by a research grant from the Calgary Laboratory Services (#10009392).http://aac.asm.org2016-09-30hb201

Isolation and purification of an enzyme hydrolyzing ochratoxin A from aspergillus niger

Ochratoxin A is a mycotoxin produced by several Aspergillus and some Penicillium species which may be present in food and feed products. It can be enzymatically hydrolyzed into ochratoxin α and l-β-phenylalanine, thereby decreasing its toxicity. The ochratoxin A degradation capacity of Aspergillus niger is well known and here we report the isolation and purification of a novel enzyme from A. niger that hydrolyzes this mycotoxin. A wheat germ medium supplemented with ochratoxin A was used to produce the enzyme, which was purified from culture filtrate by acetone precipitation and anion exchange chromatography. An overall purification of 2.5-fold with a recovery of 68% and a final specific activity of 36 U/mg was obtained. The enzyme is a metalloenzyme as it was inhibited at 10 mM EDTA, whereas PMSF had no effect. The ochratoxin A hydrolytic enzyme presented a V max of 0.44 μM/min and a K m of 0.5 mM when the reaction was carried out at pH 7.5 and 37°C.Fundação para a Ciência e a Tecnologia (FCT