Evaluating the transmission risk of SARS-CoV-2 from sewage pollution.

The presence of SARS-CoV-2 in untreated sewage has been confirmed in many countries but its incidence and infection risk in contaminated waters is poorly understood. The River Thames in the UK receives untreated sewage from 57 Combined Sewer Overflows (CSOs), with many discharging dozens of times per year. This study investigated if such discharges provide a pathway for environmental transmission of SARS-CoV-2. Samples of wastewater, surface water, and sediment collected close to six CSOs on the River Thames were assayed over eight months for SARS-CoV-2 RNA and infectious virus. Bivalves were also sampled as an indicator species of viral bioaccumulation. Sediment and water samples from the Danube and Sava rivers in Serbia, where raw sewage is also discharged in high volumes, were assayed as a positive control. No evidence of SARS-CoV-2 RNA or infectious virus was found in UK samples, in contrast to RNA positive samples from Serbia. Furthermore, this study shows that infectious SARS-CoV-2 inoculum is stable in Thames water and sediment for <3 days, while SARS-CoV-2 RNA is detectable for at least seven days. This indicates that dilution of wastewater likely limits environmental transmission, and that detection of viral RNA alone is not an indication of pathogen spillover.

The utility of screening diagnostic tests in identifying associative immune-mediated haemolytic anaemia in dogs.

The study aimed to (1) define the proportion of dogs with immune-mediated haemolytic anaemia (IMHA) that have associative and non-associative disease and (2) evaluate the utility of screening diagnostic tests in identifying potential triggers of associative IMHA. Medical records of 78 dogs diagnosed with IMHA at a specialist hospital in Sydney from July 2008 to August 2017 were reviewed. The original diagnosis was revised according to published guidelines (Garden et al., 2019) as either diagnostic, supportive or suspicious for IMHA. Associative IMHA was confirmed if immunosuppressive therapy was discontinued within six weeks of effective treatment of a potential trigger. Associative IMHA was considered possible when a potential trigger was identified but its significance could not be confirmed. Associative IMHA was confirmed (3) or suspected (7) in 10 dogs (13%, confidence interval [CI] 7.1%-22%), with 68 cases presumed to be non-associative. Associative IMHA was present in 3/29 (10.3%) of dogs with criteria diagnostic for IMHA, 4/42 (9.5%) of dogs with criteria supportive for IMHA and 3/7 (42.9%) of dogs with criteria suspicious for IMHA. Abdominal ultrasound was performed in 68 dogs and identified possible triggers in five (7.3%, CI 3.2% to 16%). Thoracic radiographs were performed in 70 dogs but did not identify any potential triggers (0%, CI 0% to 5.2%). Urine culture was performed in 22 dogs and was positive in three (14%, CI 4.7% to 33.3%). Routine screening tests, particularly thoracic radiographs, have a low yield in identifying potential triggers of associative IMHA, but are more likely to be useful in dogs fulfilling less stringent diagnostic criteria of IMHA.

Precipitation and temperature drive continental-scale patterns in stream invertebrate production.

Secondary production, the growth of new heterotrophic biomass, is a key process in aquatic and terrestrial ecosystems that has been carefully measured in many flowing water ecosystems. We combine structural equation modeling with the first worldwide dataset on annual secondary production of stream invertebrate communities to reveal core pathways linking air temperature and precipitation to secondary production. In the United States, where the most extensive set of secondary production estimates and covariate data were available, we show that precipitation-mediated, low-stream flow events have a strong negative effect on secondary production. At larger scales (United States, Europe, Central America, and Pacific), we demonstrate the significance of a positive two-step pathway from air to water temperature to increasing secondary production. Our results provide insights into the potential effects of climate change on secondary production and demonstrate a modeling framework that can be applied across ecosystems.

Rapid liquid chromatography tandem mass-spectrometry screening method for urinary metabolites of primary hyperoxaluria.

BACKGROUND: The primary hyperoxalurias are inherited disorders of glyoxylate metabolism that lead to overproduction of oxalate, urolithiasis and renal failure. Delays in diagnosis can be costly in terms of preserving renal function. Here we present a rapid liquid chromatography tandem mass-spectrometry screening method for the analysis of metabolites (primary hyperoxaluria metabolites) produced in excess by primary hyperoxaluria patients that include glycolate, glycerate and 2,4-dihydroxyglutarate. METHODS: Assay performance was compared to our existing gas chromatography-mass spectrometry method and clinical utility established by analysis of urine samples from patients with confirmed primary hyperoxalurias (11 PH1, 12 PH2 and 8 PH3) and controls ( n = 12). An additional 67 urine samples from patients with PH3 were used postvalidation to confirm the derived 2,4-dihydroxyglutarate cut-off. RESULTS: Glycolate, glycerate and 2,4-dihydroxyglutarate showed a mean bias of 3.3, -22.8 and 5.7%, respectively, compared to our previously published gas chromatography-mass spectrometry method. The mean total imprecision for glycolate, glycerate and 2,4-dihydroxyglutarate was shown to be 6.4, 10 and 11%, respectively. Clinical assessment confirmed that mean urinary glycolate, glycerate and 2,4-dihydroxyglutarate excretion were significantly elevated in patients with PH1, PH2 and PH3, respectively. The greatest sensitivity and specificity for PH1, PH2 and PH3 was achieved at cut-offs of 193, 100 and 4.9 µmol/mmol for glycolate, glycerate and 2,4-dihydroxyglutarate, respectively. CONCLUSIONS: A rapid screening method for the identification and differentiation of patients with suspected PH1, PH2 and PH3 is presented that allows focussing of genetic testing, saving time, money and, with earlier treatment, potential preservation of renal function for these patients.

Environmental risk, Oxytocin Receptor Gene (OXTR) methylation and youth callous-unemotional traits: a 13-year longitudinal study.

Youth with high callous-unemotional traits (CU) are at risk for early-onset and persistent conduct problems. Research suggests that there may be different developmental pathways to CU (genetic/constitutional vs environmental), and that the absence or presence of co-occurring internalizing problems is a key marker. However, it is unclear whether such a distinction is valid. Intermediate phenotypes such as DNA methylation, an epigenetic modification regulating gene expression, may help to clarify etiological pathways. This is the first study to examine prospective inter-relationships between environmental risk (prenatal/postnatal) and DNA methylation (birth, age 7 and 9) in the prediction of CU (age 13), for youth low vs high in internalizing problems. We focused on DNA methylation in the vicinity of the oxytocin receptor (OXTR) gene as it has been previously implicated in CU. Participants were 84 youth with early-onset and persistent conduct problems drawn from the Avon Longitudinal Study of Parents and Children. For youth with low internalizing problems (46%), we found that (i) OXTR methylation at birth associated with higher CU (age 13) as well as decreased experience of victimization during childhood (evocative epigenetic-environment correlation; birth-age 7), (ii) higher prenatal parental risks (maternal psychopathology, criminal behaviors, substance use) associated with higher OXTR methylation at birth and (iii) OXTR methylation levels were more stable across time (birth-age 9). In contrast, for youth with high internalizing problems, CU were associated with prenatal risks of an interpersonal nature (that is, intimate partner violence, family conflict) but not OXTR methylation. Findings support the existence of distinct developmental pathways to CU.

Ecosystem functioning in stream assemblages from different regions: contrasting responses to variation in detritivore richness, evenness and density.

1. The diversity of species traits in a biological assemblage varies not only with species richness, but also with species evenness and organism density, which together influence the concentration of traits within functional guilds. Potential trait diversity at local scales is also constrained by the regional species pool. Implications of such variation for spatio-temporal variability in biodiversity-ecosystem functioning relationships are likely to be complex, but are poorly understood. 2. In microcosm experiments conducted at laboratories in Sweden, Ireland and Romania, we investigated effects of species richness, evenness and density of stream-living detritivores on two related processes: detritivore leaf-processing efficiency (LPE) and growth. Assemblage composition varied among laboratories: one taxonomic order (Plecoptera) was studied in Sweden, whereas two orders, encompassing wider trait variation, were studied in Romania (Trichoptera and Plecoptera) and Ireland (Trichoptera and Isopoda). 3. Relationships between density and both LPE and growth ranged from negative to positive across the study species, highlighting the potential for density-dependent variation in process rates to alter ecosystem functioning, but indicating that such effects depend on species identity. 4. LPE varied with species diversity in the two more heterogeneous assemblages, but whereas LPE in the Romanian study was generally enhanced as richness increased, LPE in the Irish study increased only in less-even polycultures dominated by particular species. Transgressive overyielding was detected in the Irish experiment, indicating complementary resource use and/or facilitation (complementarity). These mechanisms could not be distinguished from the selection effect in the Romanian study. 5. Growth was elevated in Romanian species mixtures, reflecting positive complementarity, but lower than expected growth in some Swedish mixtures was associated with negative complementarity, indicating interspecific interference competition. 6. Our results emphasize the potential importance of detritivore diversity for stream ecosystem functioning, but both the effects of diversity on the studied processes, and the mechanisms underlying those effects, were specific to each assemblage and process. Such variability highlights challenges in generalizing impacts of diversity change for functional integrity in streams and other ecosystems in which the occurrence of important species traits fluctuates over relatively small spatio-temporal scales.

Variable and strain dependent colonisation of chickens by Escherichia coli O157.

The prevalence of enterohaemorrhagic Escherichia coli (EHEC) O157 in poultry is considered minimal compared with other species, especially ruminants. However, deliberate inoculation studies have shown that poultry are readily and persistently infected by this organism but that the mechanism of colonisation is independent of intimin, a recognised factor in host-EHEC interactions in mammalian species, and may be dependent upon flagella. Few strains of EHEC O157 have been tested in poultry and here 1-day-old and 6-week-old chicks were inoculated with seven non-toxigenic E. coli O157 strains in separate experiments. Persistence was measured semi-quantitatively by bacteriological assessment of E. coli O157 cultured from cloacal swabs (shedding score). In the 1-day-old chick model that was monitored for 43 days, all seven strains established well after inoculation. In the 6-week-old chicken model, one strain established and gave consistently high shedding for the duration of the experiment (156 days). Whereas of the remaining six strains, two persisted for 113 days, two persisted for 43 days, one persisted for 22 days and one strain was never detected.

Procedures performed by pediatric transport nurses: how "advanced" is the practice?

INTRODUCTION: Pediatric interfacility transport teams often rely on advanced practice nurses as primary care providers. These individuals may be required to transport patients without the presence of a physician. There is, however, little information in the medical literature regarding how frequently advanced practice transport nurses perform advanced procedures, how often these procedures are successfully performed, and the rate of complications associated with nurse-performed procedures. PURPOSE: The purpose of this study was to determine how frequently advanced practice transport nurses were called on to perform advanced procedures and to determine the nurses' procedural success and complication rates. DESIGN: Prospective convenience sample of consecutive pediatric interfacility transports. METHODS: Transport nurses collected data on 336 pediatric interfacility transports that were performed during a 4-month period beginning in May 1997. All patient transports occurring during the study period were included. Data regarding procedures were recorded on data collection sheets. This data included the type of procedure performed, the outcome of the procedure, and the complications associated with the procedure. The number of attempts required to successfully complete the procedure was not recorded. During or after the patient's hospitalization, the medical record was reviewed to identify potential complications related to the transport that may not have been recorded on the data collection sheet. RESULTS: Nurses performed 95.2% of transports without the presence of a physician. Twenty-six patients (8.8%) required advanced procedures. Nurses performed eight tracheal intubations. Personnel at the referring hospital performed the remaining procedures. All tracheal intubations by transport nurses were successful. There were no complications related to these procedures. All patients were transported to the receiving hospital without incident. CONCLUSIONS: Although they had considerable training for advanced procedures, the transport nurses rarely used these skills. All tracheal intubations performed by transport nurses were successful, and there were no adverse consequences related to intubation by a transport nurse.

Autism and Parkinson's disease.

The pathogenesis of Parkinson's disease, a neurodegenerative disorder, is multifaceted, having a variety of genetic and environmental factors. There is considerable evidence to support the role of toxins, particularly pesticides and herbicides, in at least some of those affected (presumably, mostly the genetically vulnerable). The pathogenesis of autism is no less complex, but little is known about the potential role of toxins for autism, a neurodevelopmental disorder. The incidence of autism appears to be rising, and early exposure to synthetic chemicals is one suspect for this rise. Impaired detoxification of certain chemicals may be common to autism and Parkinson's disease. Further study of environmental influences for either disorder may lead to important insights regarding causation for both, and perhaps for other neurodegenerative and neurodevelopmental disorders as well.

Should parents accompany pediatric interfacility ground ambulance transports? The parent's perspective.

Parental accompaniment can be a positive experience for the parent and the patient, as perceived by the parent. It can also be accomplished effectively without hindering the delivery of intratransport medical care by a nurse/nurse or nurse/physician transport team. This survey, along with the responses from other parents, led our team to adopt the position that a parent is welcome and encouraged to accompany the transport team if he or she wishes to. The team has recognized the importance of the family unit during the stressful period surrounding an acute medical issue and interfacility transport. The transport team reserves the option to ask that a parent not ride along if they suspect the parent might not function as a supportive team member (ie, the parent is belligerent, inebriated, or hostile). The parent normally rides in the passenger seat of the ambulance, and we encourage him or her to interact with the patient as much as possible. Occasionally parents ride in the back of the ambulance if the patient's situation allows for that option (ie, no anticipated need for potential interventions, number of team personnel, etc.).

Diabetes and transport: a potentially bittersweet combination.

These cases represent a portion of the spectrum of medical issues that may be seen in patients with a diagnosis of IDDM. As the first case suggests, knowledge of the disease process and an expanded differential diagnosis is imperative when acting as medical command for these patients. Interfacility transport does not only involve rapid and safe transport between institutions, but must also offer the highest level of expertise available for the referring physician and the patient. For this reason, we recommend the immediate availability of a senior level experienced pediatric physician for involvement in all but the most routine pediatric interfacility transports. Rapid recognition at the time of initial presentation or transport of the correct diagnosis in patient one may have altered potential outcome. Case 2 represents a potential untoward outcome which might be potentiated or exacerbated by the care given during transport. Although this patient's transport time was short, a similar patient may present who needs prolonged transport. The patient might also present to the transport service prior to neurologic deterioration. One must be prepared to intervene for all potential complications as they arise. Case 3 represents a patient whose physical examination suggested more intense therapy was needed than is offered by many DKA protocols. It is important to listen to what the patients are trying to tell us, rather than relying strictly on protocols or guidelines. While protocols or guidelines offer a menu of potential therapies, one must be prepared to vary from these guidelines if suggested by the patient's condition. Recognition of delayed capillary refill in patient 3 allowed for an increase in fluid administration and rapid patient improvement. While not evident with the presented short transports, the use of point of care testing in a transport vehicle can be useful for these types of patients. The opportunity to closely monitor blood chemistry evaluations and gasses can give insight about an ongoing process, suggest therapies, and help direct interventions that, in the past, often waited until the patient arrived at the receiving hospital. That additional information can be invaluable for the ill patient whose outcome may hinge on early recognition of subtle changes with subsequent appropriate interventions.