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Introduction: Optimizing naloxone dosing in the context of increasing fentanyl and ultra-potent opioid (UPO) prevalence is an important consideration for emergency health care providers. The goal of this systematic review was to evaluate the association between initial and cumulative naloxone doses on effective reversal and adverse events in undifferentiated and fentanyl/UPO overdoses. Methods: We searched Embase, MEDLINE, Cochrane Central Register of Controlled Trials, DARE, CINAHL, Science Citation Index, reference lists, toxicology websites, and conference proceedings from July to October 2018 and back to 1972. Our search included pertinent indexing terms for UPOs. We included interventional and observational studies reporting on naloxone administration for opioid toxicity reversal in people ≥12 years old. Additionally, we accessed non-traditional evidence sources (case reports and series) given this rapidly changing field. We conducted inclusion screens, data extraction and quality assessments in duplicate. We summarized study characteristics and where reported, analyzed number of patients with clinical response. Response was defined as not receiving further naloxone doses and remaining alive. Results: We included 174 studies (108 case reports and series, 55 observational, 9 interventional) with 26,660 subjects (median age 35.1; 74.2% male). We observed lower response among patients exposed to fentanyl/UPO versus heroin for initial naloxone doses ≤0.4mg (56.8% versus 80.2%) and > 0.4mg (27.0% versus 82.1%). Mean cumulative doses were higher for fentanyl/UPO (2.10 mg, SD 1.80 mg) versus heroin (1.48 mg, SD 1.68 mg) overdoses. In North American studies the median cumulative dose used was higher for fentanyl/UPO versus heroin overdoses. A dose-response curve for fentanyl/UPO studies showed marked variability in doses among responders, indicating heterogeneity. Adverse events reporting was inconsistent; 10% of subjects experienced withdrawal based on studies in which they were reported. Conclusion: This is the first systematic review to summarize proportion of patients with clinical response by naloxone dose provided. While variable reporting, study quality, heterogeneity, and our outcome definitions limit the conclusions we can draw, it appears that higher initial doses and in some cases, higher cumulative naloxone doses were used and may be necessary to reverse toxicity due to fentanyl/UPO compared to other opioids. High-quality prospective studies assessing effectiveness and safety are needed.
Introduction: Increasing opioid prescribing has been linked to an epidemic of opioid misuse. Our objective was to synthesize available evidence about patient-, prescriber-, medication-, and system-level risk factors for developing opioid misuse from prescribed opioids among patients presenting with pain unrelated to cancer. Our hypothesis was that we would identify risk factors predisposing patients to developing opioid misuse. Methods: We developed a systematic search strategy and applied it to nine electronic reference databases and six clinical trial registries. We hand searched related journals and conference proceedings, the reference lists of included studies, and the top 100 hits on Google. We included studies where a medical professional exposed adults or children to an opioid through a prescription. We excluded studies with over 50% cancer patients, palliative patients, and those with illicit opioid initiation. Two reviewers independently reviewed titles, abstracts, and full texts, and extracted data using standardized forms. We assessed study quality using risk of bias. We synthesized effect sizes of dichotomous risk factors on opioid misuse using inverse variance random-effects meta-analysis, and the inverse variance-weighted mean difference between opioid misusers and non-misusers for continuously measured factors. We conducted an a priori defined subgroup analysis among opioid-naïve patients. Results: Among 9,629 studies, 67 met our inclusion criteria. Among those who had been prescribed outpatient opioids, the following factors were associated with the development of misuse: a prior history of illicit drug use (OR: 4.21, 95% CI: 2.31-7.65), recent benzodiazepine use (OR: 2.57, 95% CI: 1.23-5.38), any mental health diagnosis (OR: 2.45, 95% CI: 1.91-3.15), any short acting (IR) opioid prescription (OR: 2.40, 95% CI: 1.15-5.02), younger age (OR: 2.19, 95%CI: 1.81-2.64), and male sex (OR: 1.23, 95% CI: 1.10-1.36). Among studies limiting their population to opioid-naïve patients, younger age was the most significant risk factor for opioid misuse (OR: 5.42, 95% CI:1.51-19.43). Conclusion: Of the risk factors examined, non-cancer pain patients with a prior history of substance use or mental health diagnoses were at highest risk for prescription opioid misuse. Younger opioid-naïve patients were at highest risk of misuse. Clinicians should consider these risk factors when managing acute pain in the emergency department.
Determining infectious cross-transmission events in healthcare settings involves manual surveillance of case clusters by infection control personnel, followed by strain typing of clinical/environmental isolates suspected in said clusters. Recent advances in genomic sequencing and cloud computing now allow for the rapid molecular typing of infecting isolates.
To facilitate rapid recognition of transmission clusters, we aimed to assess infection control surveillance using whole-genome sequencing (WGS) of microbial pathogens to identify cross-transmission events for epidemiologic review.
Clinical isolates of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, and Klebsiella pneumoniae were obtained prospectively at an academic medical center, from September 1, 2016, to September 30, 2017. Isolate genomes were sequenced, followed by single-nucleotide variant analysis; a cloud-computing platform was used for whole-genome sequence analysis and cluster identification.
Most strains of the 4 studied pathogens were unrelated, and 34 potential transmission clusters were present. The characteristics of the potential clusters were complex and likely not identifiable by traditional surveillance alone. Notably, only 1 cluster had been suspected by routine manual surveillance.
Our work supports the assertion that integration of genomic and clinical epidemiologic data can augment infection control surveillance for both the identification of cross-transmission events and the inclusion of missed and exclusion of misidentified outbreaks (ie, false alarms). The integration of clinical data is essential to prioritize suspect clusters for investigation, and for existing infections, a timely review of both the clinical and WGS results can hold promise to reduce HAIs. A richer understanding of cross-transmission events within healthcare settings will require the expansion of current surveillance approaches.
Recent infection testing algorithms (RITA) for HIV combine serological assays with epidemiological data to determine likely recent infections, indicators of ongoing transmission. In 2016, we integrated RITA into national HIV surveillance in Ireland to better inform HIV prevention interventions. We determined the avidity index (AI) of new HIV diagnoses and linked the results with data captured in the national infectious disease reporting system. RITA classified a diagnosis as recent based on an AI < 1.5, unless epidemiological criteria (CD4 count <200 cells/mm3; viral load <400 copies/ml; the presence of AIDS-defining illness; prior antiretroviral therapy use) indicated a potential false-recent result. Of 508 diagnoses in 2016, we linked 448 (88.1%) to an avidity test result. RITA classified 12.5% of diagnoses as recent, with the highest proportion (26.3%) amongst people who inject drugs. On multivariable logistic regression recent infection was more likely with a concurrent sexually transmitted infection (aOR 2.59; 95% CI 1.04–6.45). Data were incomplete for at least one RITA criterion in 48% of cases. The study demonstrated the feasibility of integrating RITA into routine surveillance and showed some ongoing HIV transmission. To improve the interpretation of RITA, further efforts are required to improve completeness of the required epidemiological data.
In 785 mother–child (50% male) pairs from a longitudinal epidemiological birth cohort, we investigated associations between inflammation-related epigenetic polygenic risk scores (i-ePGS), environmental exposures, cognitive function, and child and adolescent internalizing and externalizing problems. We examined prenatal and postnatal effects. For externalizing problems, one prenatal effect was found: i-ePGS at birth associated with higher externalizing problems (ages 7–15) indirectly through lower cognitive function (age 7). For internalizing problems, we identified two effects. For a prenatal effect, i-ePGS at birth associated with higher internalizing symptoms via continuity in i-ePGS at age 7. For a postnatal effect, higher postnatal adversity exposure (birth through age 7) associated with higher internalizing problems (ages 7–15) via higher i-ePGS (age 7). Hence, externalizing problems were related mainly to prenatal effects involving lower cognitive function, whereas internalizing problems appeared related to both prenatal and postnatal effects. The present study supports a link between i-ePGS and child and adolescent mental health.
The present review revisits three hypothesized models that potentially could explain how prenatal maternal stress influences fetal development, birth outcomes, and subsequent developmental psychopathology. These models were mostly based on animal models, and new evidence for these models from human studies is evaluated. Furthermore, divergent trajectories from prenatal exposure to adversities to offspring affected outcomes are reviewed, including the comparison of studies on prenatal maternal stress with research on maternal substance use and maternal malnutrition during pregnancy. Finally, new directions in research on the mechanism underlying prenatal stress effects on human offspring is summarized. While it is concluded that there is abundant evidence for the negative associations between prenatal maternal stress and offspring behavioral, brain, and psychopathological outcomes in humans, there is no consistent evidence for specific mechanisms or specific outcomes in relation to stress exposure in utero. Rather, principles of multifinality and equifinality best describe the consequences for the offspring, suggesting a generic vulnerability and different pathways from prenatal adversities to developmental psychopathology, which complicates the search for underlying mechanisms. New and promising directions for research are provided to get a better understanding of how prenatal stress gets under the skin to affect fetal development.
Supportive social relationships can reduce both psychological and physiological responses to stressful experiences. Recently, studies have also assessed the potential for social relationships to buffer the intergenerational transmission of stress. The majority of these studies, however, have focussed on social learning as a mechanism responsible for the intergenerational transmission of stress. Evidence of biological mechanisms is lacking. The objective of the current study was, therefore, to determine whether the association between maternal adverse childhood experiences (ACEs) and infant hypothalamic–pituitary–adrenal (HPA) axis function is mediated by maternal HPA axis function during pregnancy and moderated by social support. Data were from 243 mother–infant dyads enrolled in a prospective longitudinal cohort (the Alberta Pregnancy Outcomes and Nutrition Study). Maternal history of ACEs was retrospectively assessed while maternal perceived social support and salivary cortisol were assessed prospectively at 6–22 weeks gestation (Time 1) and 27–37 weeks gestation (Time 2), and infant cortisol reactivity to a laboratory stressor and maternal perceived social support were assessed at 5–10 months postnatal (Time 3). Results revealed that maternal HPA axis function during pregnancy mediated the effects of maternal ACEs on infant HPA axis reactivity, suggesting that the maternal HPA axis is a mechanism by which maternal early life stress is transmitted to offspring. Furthermore, social support in the prenatal and postnatal periods moderated the cascade from maternal ACEs to infant HPA axis reactivity. Specifically, prenatal social support moderated the association between ACEs and maternal HPA axis function during pregnancy, and postnatal social support moderated the association between maternal HPA axis function and infant cortisol reactivity. These findings highlight the social sensitivity of the HPA axis and suggest the utility of social relationships as an intervention target to reduce the effects of maternal early life stress on infant outcomes.
Psychotropic medication use and psychiatric symptoms during pregnancy each are associated with adverse neurodevelopmental outcomes in offspring. Commonly, studies considering medication effects do not adequately assess symptoms, nor evaluate children when the effects are believed to occur, the fetal period. This study examined maternal serotonin reuptake inhibitor and polypharmacy use in relation to serial assessments of five indices of fetal neurobehavior and Bayley Scales of Infant Development at 12 months in N = 161 socioeconomically advantaged, non-Hispanic White women with a shared risk phenotype, diagnosed major depressive disorder. On average fetuses showed the expected development over gestation. In contrast, infant average Bayley psychomotor and mental development scores were low (M = 84.10 and M = 89.92, range of normal limits 85–114) with rates of delay more than 2–3 times what would be expected based on this measure's normative data. Controlling for prenatal and postnatal depressive symptoms, prenatal medication effects on neurobehavioral development were largely undetected in the fetus and infant. Mental health care directed primarily at symptoms may not address the additional psychosocial needs of women parenting infants. Speculatively, prenatal serotonin reuptake inhibitor exposure may act as a plasticity rather than risk factor, potentially enhancing receptivity to a nonoptimal postnatal environment in some mother–infant dyads.
Background: Acromegaly is associated with significant morbidity. The purpose of this study was to establish characteristics and outcomes of patients treated for acromegaly at The Ottawa Hospital, to compare our results with published reports from other centers and to identify opportunities to improve patient care. Methods: A retrospective chart review of patients surgically and medically treated for acromegaly between January 1, 2007 and December 31, 2016 was completed. Demographic information, biochemical data, presenting features, disease comorbidities, treatment interventions, and were collected. Results: Fifty-one patients were identified using CCI/ICD-10 codes and IGF-1 levels. Similar to other centers, the majority of patients had a macroadenoma (78.4% vs 11.8%) with a high percentage invading the cavernous sinus (57.5%). While surgical intervention was performed in 90% of patients, only 23.3% of patient achieved surgical cure (IGF-1 normalization within reference range). Approximately 30% of patients were controlled with adjuvant medical therapy while more than 40 % had elevated IGF-1 levels at last follow-up. Radiotherapy was less commonly used. Conclusions: Despite a multi-modal treatment approach for acromegaly, outcomes are variable. This study highlights the need for further research to better understand factors associated with surgical cure, response to medical therapy and the role of radiotherapy.
Research focus in recent years on magnetic behaviour of transition metal (TM) ions embedded in semiconductors has shifted from intrinsic effects to extrinsic effects such as the formation of nanoclusters of the TM ions and the influence of the host matrix on their magnetic behaviour. Our studies, using conversion electron Mössbauer Spectroscopy and magnetization measurements, on SiO2 and Al2O3 substrates implanted with 4 at. % Fe, show ferromagnetic behaviour of α-Fe clusters in amorphous SiO2, but α-Fe2O3 clusters displaying superparamagnetic relaxation in crystalline Al2O3.
Objectives: Preterm children demonstrate deficits in executive functions including inhibition, working memory, and cognitive flexibility; however, their goal setting abilities (planning, organization, strategic reasoning) remain unclear. This study compared goal setting abilities between very preterm (VP: <30 weeks/<1250 grams) and term born controls during late childhood. Additionally, early risk factors (neonatal brain abnormalities, medical complications, and sex) were examined in relationship to goal setting outcomes within the VP group. Methods: Participants included 177 VP and 61 full-term born control children aged 13 years. Goal setting was assessed using several measures of planning, organization, and strategic reasoning. Parents also completed the Behavior Rating Inventory of Executive Function. Regression models were performed to compare groups, with secondary analyses adjusting for potential confounders (sex and social risk), and excluding children with major neurosensory impairment and/or IQ<70. Within the VP group, regression models were performed to examine the relationship between brain abnormalities, medical complications, and sex, on goal setting scores. Results: The VP group demonstrated a clear pattern of impairment and inefficiency across goal setting measures, consistent with parental report, compared with their full-term born peers. Within the VP group, moderate/severe brain abnormalities on neonatal MRI predicted adverse goal setting outcomes at 13. Conclusions: Goal setting difficulties are a significant area of concern in VP children during late childhood. These difficulties are associated with neonatal brain abnormalities, and are likely to have functional consequences academically, socially and vocationally. (JINS, 2018, 24, 372–381)
Objectives: Studies suggest that impairments in some of the same domains of cognition occur in different neuropsychiatric conditions, including those known to share genetic liability. Yet, direct, multi-disorder cognitive comparisons are limited, and it remains unclear whether overlapping deficits are due to comorbidity. We aimed to extend the literature by examining cognition across different neuropsychiatric conditions and addressing comorbidity. Methods: Subjects were 486 youth consecutively referred for neuropsychiatric evaluation and enrolled in the Longitudinal Study of Genetic Influences on Cognition. First, we assessed general ability, reaction time variability (RTV), and aspects of executive functions (EFs) in youth with non-comorbid forms of attention-deficit/hyperactivity disorder (ADHD), mood disorders and autism spectrum disorder (ASD), as well as in youth with psychosis. Second, we determined the impact of comorbid ADHD on cognition in youth with ASD and mood disorders. Results: For EFs (working memory, inhibition, and shifting/ flexibility), we observed weaknesses in all diagnostic groups when participants’ own ability was the referent. Decrements were subtle in relation to published normative data. For RTV, weaknesses emerged in youth with ADHD and mood disorders, but trend-level results could not rule out decrements in other conditions. Comorbidity with ADHD did not impact the pattern of weaknesses for youth with ASD or mood disorders but increased the magnitude of the decrement in those with mood disorders. Conclusions: Youth with ADHD, mood disorders, ASD, and psychosis show EF weaknesses that are not due to comorbidity. Whether such cognitive difficulties reflect genetic liability shared among these conditions requires further study. (JINS, 2018, 24, 91–103)
The aim of this study was to ascertain farmers’ knowledge of the risk of spread of infection from animals to humans, and their transmission prevention practices. This was a survey of farmers who submitted material to Ireland's Regional Veterinary Laboratories in 2015. There was an 84% response rate (1044 farmers). Ninety per cent of farmers were not aware that infection can be acquired from apparently healthy animals. Over half were not aware that disease could be contracted from sick poultry or pets. Conversely, the knowledge of the risk to pregnant women of infection from birthing animals was high (88%). Four-fifths of farmers sourced drinking water from a private well, and of these, 62% tested their water less frequently than once a year. Of dairy farmers, 39% drank unpasteurised milk once a week or more frequently. Veterinarians were the most commonly cited information source for diseases on farms. The survey findings indicate that the level of farmers’ knowledge and awareness of the spread of infection from animals to humans is a concern. Further education of the farming community is needed to increase awareness of both the potential biohazards present on farms and the practical measures that can be taken to mitigate the risk of zoonoses.
Whole apples have not been previously implicated in outbreaks of foodborne bacterial illness. We investigated a nationwide listeriosis outbreak associated with caramel apples. We defined an outbreak-associated case as an infection with one or both of two outbreak strains of Listeria monocytogenes highly related by whole-genome multilocus sequence typing (wgMLST) from 1 October 2014 to 1 February 2015. Single-interviewer open-ended interviews identified the source. Outbreak-associated cases were compared with non-outbreak-associated cases and traceback and environmental investigations were performed. We identified 35 outbreak-associated cases in 12 states; 34 (97%) were hospitalized and seven (20%) died. Outbreak-associated ill persons were more likely to have eaten commercially produced, prepackaged caramel apples (odds ratio 326·7, 95% confidence interval 32·2–3314). Environmental samples from the grower's packing facility and distribution-chain whole apples yielded isolates highly related to outbreak isolates by wgMLST. This outbreak highlights the importance of minimizing produce contamination with L. monocytogenes. Investigators should perform single-interviewer open-ended interviews when a food is not readily identified.
To determine the length and position of a thyroidectomy scar that is cosmetically most appealing to naïve raters.
Images of thyroidectomy scars were reproduced on male and female necks using digital imaging software. Surgical variables studied were scar position and length. Fifteen raters were presented with 56 scar pairings and asked to identify which was preferred cosmetically. Twenty duplicate pairings were included to assess rater reliability. Analysis of variance was used to determine preference.
Raters preferred low, short scars, followed by high, short scars, with long scars in either position being less desirable (p < 0.05). Twelve of 15 raters had acceptable intra-rater and inter-rater reliability.
Naïve raters preferred low, short scars over the alternatives. High, short scars were the next most favourably rated. If other factors influencing incision choice are considered equal, surgeons should consider these preferences in scar position and length when planning their thyroidectomy approach.
Four flares were observed on the late-type binary YY Gem in March 1988 during a total monitoring time of 408 min. The flares were unusual in that there is a periodicity in their occurrence, being separated by 48 ± 3 min. Considering the flares to be formed as a stochastic process, we find that the probability of these events occurring by chance is 0.5%. Modelling indicates that for quite reasonable input parameters (e.g. a spot field strength of 1000 G and a filament with mass per unit length of 106g cm-1), the flare periodicity can be explained in terms of filament oscillations. The only requirement is that there should be a filament at these heights where the magnetic field drops inversely proportional to the height.
The algal polysaccharides laminarin (LAM) and fucoidan (FUC) have potent anti-inflammatory activities in the gastrointestinal tract. Our objective was to examine the impact of prior consumption of LAM and/or FUC on pathology and inflammation following a dextran sodium sulfate (DSS) challenge in pigs. Pigs (n 7/group) were assigned to one of five experimental groups for 56 d. From 49–55 d, distilled water or DSS was administered intragastrically. The experimental groups were: (1) basal diet + distilled water (control); (2) basal diet + DSS (DSS); (3) basal diet + FUC + DSS (FUC + DSS); (4) basal diet + LAM + DSS (LAM + DSS); and (5) basal diet + LAM + FUC + DSS (LAMFUC + DSS). The DSS group had decreased body-weight gain (P < 0·05) and serum xylose (P < 0·05), and increased proximal colon pathology score (P < 0·05), diarrhoeal score (P < 0·001) and colonic Enterobacteriaceae (P < 0·05) relative to the control group. The FUC + DSS (P < 0·01), LAM + DSS (P < 0·05) and LAMFUC + DSS (P < 0·05) groups had improved diarrhoeal score, and the LAMFUC + DSS (P < 0·05) group had improved body weight relative to the DSS group. The FUC + DSS group (P < 0·001), LAM + DSS group (P < 0·05) and LAMFUC + DSS group (P < 0·001) had lower IL-6 mRNA abundance relative to the DSS group. The LAM + DSS group had reduced Enterobacteriaceae in proximal colon digesta relative to the DSS group (P < 0·05). In conclusion, FUC or a combination of FUC and LAM improved body-weight loss, diarrhoeal scores and clinical variables associated with a DSS challenge in pigs, in tandem with a reduction in colonic IL-6 mRNA abundance.
Non-right handedness (NRH) is reportedly more common in very preterm (VPT; <32 weeks’ gestation) children compared with term-born peers, but it is unclear whether neonatal brain injury or altered brain morphology and microstructure underpins NRH in this population. Given that NRH has been inconsistently reported to be associated with cognitive and motor difficulties, this study aimed to examine associations between handedness and neurodevelopmental outcomes in VPT 7-year-olds. Furthermore, the relationship between neonatal brain injury and integrity of motor tracts (corpus callosum and corticospinal tract) with handedness at age 7 years in VPT children was explored. One hundred seventy-five VPT and 69 term-born children completed neuropsychological and motor assessments and a measure of handedness at 7 years’ corrected age. At term-equivalent age, brain injury on MRI was assessed and diffusion tensor measures were obtained for the corpus callosum and posterior limb of the internal capsule. There was little evidence of stronger NRH in the VPT group compared with term controls (regression coefficient [b] −1.95, 95% confidence interval [−5.67, 1.77]). Poorer academic and working memory outcomes were associated with stronger NRH in the VPT group. While there was little evidence that neonatal unilateral brain injury was associated with stronger NRH, increased area and fractional anisotropy of the corpus callosum splenium were predictive of stronger NRH in the VPT group. VPT birth may alter the relationship between handedness and academic outcomes, and neonatal corpus callosum integrity predicts hand preference in VPT children at school age. (JINS, 2015, 21, 610–621)
The experiment investigated the effect of maternal dietary supplementation of seaweed-derived polysaccharides (SDP) (–SDP v. +SDP, n 20) from day 83 of gestation until weaning (day 28) on selected sow faeces and piglet digesta microbiota populations, piglet small-intestinal morphology, and intestinal nutrient transporter and inflammatory cytokine gene expression at birth, 48 h after birth and weaning. The effect of maternal dietary treatment on the piglet gene expression profile of inflammatory cytokines in the colon following a lipopolysaccharide (LPS) challenge was also investigated. Dietary SDP reduced sow faecal Enterobacteriaceae gene numbers at parturition. Small-intestinal morphology, nutrient transporter and cytokine gene expression in newborn piglets did not differ between maternal dietary treatments (P > 0·10). At 48 h after birth, sodium–glucose-linked transporter 1 gene expression was down-regulated in the ileum of piglets suckling the SDP-supplemented sows compared with those suckling the basal sows (P = 0·050). There was a SDP × LPS challenge interaction on IL-1 and IL-6 gene expression in the colon of piglets (P < 0·05). The gene expression of IL-1 and IL-6 was down-regulated in the LPS-challenged colon of piglets suckling the SDP sows compared with those suckling the basal sows (P < 0·05). However, there was no difference in IL-1 and IL-6 gene expression in the unchallenged colon between treatment groups. At weaning, piglets suckling the SDP-supplemented sows had increased villus height in the jejunum and ileum compared with those suckling the basal-fed sows (P < 0·05). In conclusion, maternal dietary SDP supplementation enhanced the immune response of suckling piglets and improved gut morphology, making them more immune competent to deal with post-weaning adversities.
In the present study, a 2 × 2 factorial arrangement was conducted to investigate the effect of maternal supplementation with seaweed extracts ( − SWE v. +SWE, n 20) from day 83 of gestation until weaning (day 28) on post-weaning (PW) growth performance, faecal score, faecal enterotoxigenic Escherichia coli (ETEC) toxin quantification, intestinal histology and cytokine mRNA of unchallenged and ETEC-challenged pigs. Pigs were ETEC challenged on day 9 PW. There was a maternal treatment × challenge (SWE × ETEC) interaction effect on growth performance and faecal score (P< 0·05). Pigs from SWE-supplemented sows and ETEC-challenged (SE) had higher average daily gain (ADG) during 0–13 d PW and reduced faecal score during 0–72 h post-challenge than those from basal-fed sows and ETEC-challenged (BE) (P< 0·05). However, there was no difference between unchallenged pigs from the SWE-supplemented sows (SC) and basal-fed sows (BC) (P>0·10). Pigs from the SWE-supplemented sows had reduced heat-labile enterotoxin gene copy numbers than those from the basal-fed sows (P< 0·05). Maternal SWE supplementation increased the villus height in the ileum of pigs (P< 0·05). There was a SWE × ETEC interaction effect (P< 0·05) on IL-6 mRNA and a SWE × gastrointestinal (GI) region interaction effect (P< 0·05) on transforming growth factor-β1 (TGF-β1) and TNF-α mRNA. IL-6 mRNA was down-regulated in SC pigs than BC pigs (P< 0·05). However, there was no difference in IL-6 mRNA between SE and BE pigs. The mRNA of TGF-β1 and TNF-α was down-regulated in the colon of pigs from the SWE-supplemented sows compared with those from the basal-fed sows (P< 0·05). However, there was no difference in TGF-β1 and TNF-α mRNA in the ileum between the pigs from the SWE-supplemented sows and basal-fed sows. In conclusion, maternal SWE supplementation improves ADG and the aspects of GI health of weaned pigs following an ETEC challenge.