The view of Hong Kong parents on secondary use of dried blood spots in newborn screening program.

BACKGROUND: Residual dried blood spots (rDBS) from newborn screening programmes represent a valuable resource for medical research, from basic sciences, through clinical to public health. In Hong Kong, there is no legislation for biobanking. Parents' view on the retention and use of residual newborn blood samples could be cultural-specific and is important to consider for biobanking of rDBS. OBJECTIVE: To study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents. METHODS: A mixed-method approach was used to study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents of children 0-3 years or expecting parents through focus groups (8 groups; 33 participants) and a survey (n = 1012, 85% mothers) designed with insights obtained from the focus groups. We used framework analysis to summarise the themes as supportive factors, concerns and critical arguments for retention and secondary use of rDBS from focus group discussion. We used multiple logistic regression to assess factors associated with support for retention and secondary use of rDBS in the survey. RESULTS: Both in focus groups and survey, majority of parents were not aware of the potential secondary use of rDBS. Overall secondary use of rDBS in medical research was well accepted by a large proportion of Hong Kong parents, even if all potential future research could not be specified in a broad consent. However parents were concerned about potential risks of biobanking rDBS including leaking of data and mis-use of genetic information. Parents wanted to be asked for permission before rDBS are stored and mainly did not accept an "opt-out" approach. The survey showed that parents born in mainland China, compared to Hong Kong born parents, had lower awareness of newborn screening but higher support in biobanking rDBS. Higher education was associated with support in rDBS biobanking only among fathers. CONCLUSION: Long-term storage and secondary use of rDBS from newborn screening for biomedical research and a broad consent for biobanking of rDBS are generally acceptable to Hong Kong parents given their autonomy is respected and their privacy is protected, highlighting the importance of an accountable governance and a transparent access policy for rDBS biobanks.

Arbidol and Other Low-Molecular-Weight Drugs That Inhibit Lassa and Ebola Viruses.

Antiviral therapies that impede virus entry are attractive because they act on the first phase of the infectious cycle. Drugs that target pathways common to multiple viruses are particularly desirable when laboratory-based viral identification may be challenging, e.g., in an outbreak setting. We are interested in identifying drugs that block both Ebola virus (EBOV) and Lassa virus (LASV), two unrelated but highly pathogenic hemorrhagic fever viruses that have caused outbreaks in similar regions in Africa and share features of virus entry: use of cell surface attachment factors, macropinocytosis, endosomal receptors, and low pH to trigger fusion in late endosomes. Toward this goal, we directly compared the potency of eight drugs known to block EBOV entry with their potency as inhibitors of LASV entry. Five drugs (amodiaquine, apilimod, arbidol, niclosamide, and zoniporide) showed roughly equivalent degrees of inhibition of LASV and EBOV glycoprotein (GP)-bearing pseudoviruses; three (clomiphene, sertraline, and toremifene) were more potent against EBOV. We then focused on arbidol, which is licensed abroad as an anti-influenza drug and exhibits activity against a diverse array of clinically relevant viruses. We found that arbidol inhibits infection by authentic LASV, inhibits LASV GP-mediated cell-cell fusion and virus-cell fusion, and, reminiscent of its activity on influenza virus hemagglutinin, stabilizes LASV GP to low-pH exposure. Our findings suggest that arbidol inhibits LASV fusion, which may partly involve blocking conformational changes in LASV GP. We discuss our findings in terms of the potential to develop a drug cocktail that could inhibit both LASV and EBOV.IMPORTANCE Lassa and Ebola viruses continue to cause severe outbreaks in humans, yet there are only limited therapeutic options to treat the deadly hemorrhagic fever diseases they cause. Because of overlapping geographic occurrences and similarities in mode of entry into cells, we seek a practical drug or drug cocktail that could be used to treat infections by both viruses. Toward this goal, we directly compared eight drugs, approved or in clinical testing, for the ability to block entry mediated by the glycoproteins of both viruses. We identified five drugs with approximately equal potencies against both. Among these, we investigated the modes of action of arbidol, a drug licensed abroad to treat influenza infections. We found, as shown for influenza virus, that arbidol blocks fusion mediated by the Lassa virus glycoprotein. Our findings encourage the development of a combination of approved drugs to treat both Lassa and Ebola virus diseases.

Effect of a commercial anionic dietary supplement on urinary pH and concentrations of electrolytes and pH in blood of horses.

Aims: To compare urine urinary pH, blood pH and concentration of electrolytes in blood of healthy horses fed an anionic salt supplement to achieve diets with a dietary cation-anion difference (DCAD) of -40 or 0 mEq/kg DM, with horses a fed a diet with a DCAD of 85 mEq/kg DM.Methods: Eight healthy horses received each of three diets in a randomised crossover design. Diets consisted of grass hay and concentrate feed, with a varying amount of an anionic supplement to achieve a DCAD of 85 (control), 0 or -40 mEq/kg DM. They were fed for 14 days each with a washout period of 7 days between. Urine pH was measured daily and blood samples were collected on Days 0, 7 and 14 of each study period for the measurement of pH and concentration of electrolytes.Results: Four horses voluntarily consumed the anionic supplement with their feed, but four horses required oral supplement administration via dose syringe. During the study period mean urine pH was lower in horses fed diets with a DCAD of 0 (6.91; SD 0.04) and -40 (6.83; SD 0.04) mEq/kg DM compared to the control diet (7.30; SD 0.04). Compared with horses fed the control diet, mean urine pH was lower in horses fed the 0 and -40 mEq/kg DM diets on Days 1-12 and 14 (p < 0.05) of the study period. On Day 13 it was only lower in horses fed the -40 mEq/kg DM diet (p < 0.01). Urine pH was similar for horses fed the 0 and -40 mEq/kg DM diets (p = 0.151). The DCAD of the diet had no effect on blood pH, ionised Ca or anion gap. Mean concentrations of bicarbonate in blood were affected by diet (p = 0.049); they were lower when horses were fed the 0 mEq/kg diet relative to the control diet on Day 14.Conclusions and clinical relevance: The anionic supplement reduced urine pH in horses fed diets with a DCAD of 0 or -40 mEq/kg DM compared with 85 mEq/kg DM. However as urinary pH did not fall below pH 6.5, the pH below which calcium carbonate uroliths do not form, this reduction in urine pH is unlikely to be clinically significant. The supplement was variably palatable and showed minimal promise as an effective urinary acidifier at the doses administered in this study.

Correction to: In utero exposure to gestational diabetes and adiposity: does breastfeeding make a difference?

In the original version of this article, the Publisher incorrectly listed the affiliation of the author, G.M. Leung. The correct affiliation for this author should be: School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.

In utero exposure to gestational diabetes and adiposity: does breastfeeding make a difference?

BACKGROUND/OBJECTIVES: Short-term breastfeeding from mothers with gestational diabetes (GDM) may programme metabolism and increase offspring diabetes risk. We examined the association of in utero GDM exposure with adiposity from infancy to adolescence, and whether any association was modified by breastfeeding during early infancy. METHODS: In the prospective Chinese birth cohort "Children of 1997" (n = 7342, 88% follow-up rate), generalised estimate equations with multiple imputation were used to assess associations of in utero GDM exposure with age- and sex-specific body mass index (BMI) z-score during infancy (3 and 9 months), childhood (2- < 8 years) and adolescence (8-16 years), adjusted for sex, parity, maternal age, birth place, preeclampisa, smoking, and family socio-economic position. We also tested whether the associations differed by mode of infant feeding (always formula-fed, mixed, always breastfed) during the first three months of life. RESULTS: In utero GDM exposure (7.5%) was associated with a lower BMI z-score during infancy (-0.13, 95% confidence interval (CI) -0.22, -0.05) but higher BMI z-scores during childhood (0.14, 95% CI 0.03, 0.25) and adolescence (0.25 95% CI 0.11, 0.38). Breastfeeding for the first three months did not modify the association of in utero GDM status with subsequent BMI (all p values for interaction >0.4). CONCLUSIONS: In utero GDM exposure was associated with greater adiposity during childhood and adolescence. Breastfeeding in early infancy from mothers with GDM was not associated with greater adiposity in children and thus should still be encouraged.

Dietitian-led lifestyle modification programme for obese Chinese adolescents with non-alcoholic fatty liver disease: a randomized controlled study.

BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is increasing. This study evaluated the efficacy of a dietitian-led lifestyle modification programme (D-LMP) to reduce NAFLD in obese adolescents. METHODS: Subjects with intra-hepatic triglyceride content (IHTC) equal to or greater than 5% diagnosed by proton-magnetic resonance spectroscopy (1H-MRS) were enroled and randomly assigned to either the D-LMP intervention or conventional paediatrician-led consultation (P-CON) group. Subjects in the P-CON group received usual care consisting of a consultation by a paediatrician with the child and parents every 16 weeks. Intention-to-treat analysis was used for data analysis. RESULTS: Fifty-two subjects were recruited, with 26 in each group. After the initiation phase (at week-16), there was a greater difference in the change in the IHTC and BMI z-score in the D-LMP group (P = 0.029 and <0.001, respectively) and there was a decrease in dietary intake of fat content (P = 0.019). After 52 weeks of the maintenance phase, both groups had reductions of IHTC to 2-3% and there was no intergroup difference in the rate of reduction. During the maintenance phase, parents' involvement was minimal in the D-LMP group, with only three parents accompanying their children to attend the dietitian sessions. In contrast, over 90% of the parents in the P-CON group regularly accompanied their children to attend the consultations suggesting the possibility that regular parental and paediatrician involvement may contribute to increasing awareness on fatty liver complications. Multivariate analysis showed that only reduction in body fat remained as an independent factor associated with remission of NAFLD at the end of both study phases. CONCLUSIONS: A dietitian-led lifestyle modification intervention reduced IHTC, BMI z-score and body fat in obese Chinese adolescents with NAFLD. To sustain the effect of this intervention, regular parental and paediatrician involvement may be important.

Prognosis of the infected diabetic foot ulcer: a 12-month prospective observational study.

AIMS: To determine clinical outcomes and explore prognostic factors related to ulcer healing in people with a clinically infected diabetic foot ulcer. METHODS: This multicentre, prospective, observational study reviewed participants' data at 12 months after culture of a diabetic foot ulcer requiring antibiotic therapy. From participants' notes, we obtained information on the incidence of wound healing, ulcer recurrence, lower extremity amputation, lower extremity revascularization and death. We estimated the cumulative incidence of healing at 6 and 12 months, adjusted for lower extremity amputation and death using a competing risk analysis, and explored the relationship between baseline factors and healing incidence. RESULTS: In the first year after culture of the index ulcer, 45/299 participants (15.1%) had died. The ulcer had healed in 136 participants (45.5%), but recurred in 13 (9.6%). An ipsilateral lower extremity amputation was recorded in 52 (17.4%) and revascularization surgery in 18 participants (6.0%). Participants with an ulcer present for ~2 months or more had a lower incidence of healing (hazard ratio 0.55, 95% CI 0.39 to 0.77), as did those with a PEDIS (perfusion, extent, depth, infection, sensation) perfusion grade of ≥2 (hazard ratio 0.37, 95% CI 0.25 to 0.55). Participants with a single ulcer on their index foot had a higher incidence of healing than those with multiple ulcers (hazard ratio 1.90, 95% CI 1.18 to 3.06). CONCLUSIONS: Clinical outcomes at 12 months for people with an infected diabetic foot ulcer are generally poor. Our data confirm the adverse prognostic effect of limb ischaemia, longer ulcer duration and the presence of multiple ulcers.

Waist-to-height ratio as a measure of abdominal obesity in southern Chinese and European children and adolescents.

BACKGROUND: Waist-to-height ratio (WHtR), with a 0.5 threshold (WHtR0.5), is regarded as a simple age- and gender-independent criterion of abdominal obesity (AO) and a better predictor than the 90th percentile of waist circumference (WCP90). OBJECTIVE: An analysis of gender and ethnic differences of WHtR and other AO indices between children and adolescents from southern China (HK: Hong-Kong, China) and Europe (LD: Lódz, Poland). SUBJECTS: Two large cross-sectional surveys of children and adolescents aged 7-19 years, one from LD (13 172) and one from HK (14 566). METHODS: The percentile and standardized values of WHtR and other parameters (WC, body mass index (BMI)) were assessed using the LMS method. The WHtR values corresponding to WCP90 and to the BMI definition of global obesity (BMIP95) were evaluated with the polynomial regression model. The compliance of the AO prevalence data, obtained with two criteria (WCP90 vs WHtR0.5) was analyzed using Cohen's kappa index (κC). RESULTS: The WHtR data of Polish subjects were generally higher than those of their HK peers, and the ethic differences increased with age. The WHtR values of HK boys showed a stronger relationship with BMI z-score. WHtR corresponding to WCP90 assumed values <0.5. An application of Cohen's kappa coefficient (κC) to Polish subjects showed either 'substantial' (κC>0.6) or 'almost perfect' (κC>0.8) agreement in the AO prevalence for both criteria (WCP90 and WHtR0.5). For these criteria, either 'fair' (κC <0.4) or 'moderate' (κC<0.6) AO consistency ratings were observed among HK girls. In HK boys, a significant difference in the prevalence of AO was observed, independent of the criterion used. CONCLUSIONS: Our results provide further evidence of the need for developing ethnic-specific WC charts and for recommending that a WHtR cutoff of 0.5 may not be appropriate to predict cardiometabolic risk in children of different ethnic groups.

Using cognitive pre-testing methods in the development of a new evidenced-based pressure ulcer risk assessment instrument.

BACKGROUND: Variation in development methods of Pressure Ulcer Risk Assessment Instruments has led to inconsistent inclusion of risk factors and concerns about content validity. A new evidenced-based Risk Assessment Instrument, the Pressure Ulcer Risk Primary Or Secondary Evaluation Tool - PURPOSE-T was developed as part of a National Institute for Health Research (NIHR) funded Pressure Ulcer Research Programme (PURPOSE: RP-PG-0407-10056). This paper reports the pre-test phase to assess and improve PURPOSE-T acceptability, usability and confirm content validity. METHODS: A descriptive study incorporating cognitive pre-testing methods and integration of service user views was undertaken over 3 cycles comprising PURPOSE-T training, a focus group and one-to-one think-aloud interviews. Clinical nurses from 2 acute and 2 community NHS Trusts, were grouped according to job role. Focus group participants used 3 vignettes to complete PURPOSE-T assessments and then participated in the focus group. Think-aloud participants were interviewed during their completion of PURPOSE-T. After each pre-test cycle analysis was undertaken and adjustment/improvements made to PURPOSE-T in an iterative process. This incorporated the use of descriptive statistics for data completeness and decision rule compliance and directed content analysis for interview and focus group data. Data were collected April 2012-June 2012. RESULTS: Thirty-four nurses participated in 3 pre-test cycles. Data from 3 focus groups, 12 think-aloud interviews incorporating 101 PURPOSE-T assessments led to changes to improve instrument content and design, flow and format, decision support and item-specific wording. Acceptability and usability were demonstrated by improved data completion and appropriate risk pathway allocation. The pre-test also confirmed content validity with clinical nurses. CONCLUSIONS: The pre-test was an important step in the development of the preliminary PURPOSE-T and the methods used may have wider instrument development application. PURPOSE-T proposes a new approach to pressure ulcer risk assessment, incorporating a screening stage, the inclusion of skin status to distinguish between those who require primary prevention and those who require secondary prevention/treatment and the use of colour to support pathway allocation and decision making. Further clinical evaluation is planned to assess the reliability and validity of PURPOSE-T and it's impact on care processes and patient outcomes.

Spinal Cord Hamartomatous Myelodysplasia in 2 Horses With Clinical Neurologic Deficits.

Two horses euthanized for neurologic deficits were diagnosed with hamartomatous myelodysplasia of the spinal cord. One was a 5-week-old Holsteiner colt exhibiting spasms of muscle rigidity in the extensor muscles of the limbs and epaxial muscles, and the other was a 3-year-old Thoroughbred colt exhibiting progressive ataxia and hypermetria in the pelvic limbs. Each had focal disorganization of the white and gray matter of the spinal cord forming a mass interspersed with neurons, glial cells, and disoriented axon bundles. In the Holsteiner colt, the mass was at the level of C5 and included islands of meningeal tissue contiguous with the leptomeninges. The mass occluded the central canal forming hydromyelia cranial to the occlusion. In the Thoroughbred colt, the mass was at the level of L1 on the dorsal periphery of the spinal cord and did not involve the central canal.

Normative values of motor performance and their relationship with BMI status in Hong Kong preschoolers.

This study aimed to establish sex- and age-specific reference values for motor performance (MP) in Hong Kong preschoolers aged 3-5 years old and examine the relationship between MP and BMI status. A cross-sectional study was conducted among 5579 preschoolers in Hong Kong. Three MP tests were administered, and height and weight information were collected. GAMLSS was used to compute the normative values of the motor tests. Boys outperformed girls in activities requiring muscle strength and power, while girls outperformed boys in activities requiring balance and coordination. The MP scores increased with age for both overarm beanbag throw and standing long jump for both sexes, while the one-leg balance scores showed larger differences between P50 and P95 in older preschoolers. Children with excessive weight performed worse in standing long jump and one-leg balance compared to their healthy weight peers. This study provides valuable information on the MP of preschoolers in Hong Kong, including sex- and age-specific reference values and the association between BMI status and MP scores. These findings can serve as a reference for future studies and clinical practice and highlight the importance of promoting motor skill development in preschoolers, particularly those who are overweight or obese.

Evidence-based decisions for local and systemic wound care.

BACKGROUND: Decisions on local and systemic wound treatment vary among surgeons and are frequently based on expert opinion. The aim of this meta-review was to compile best available evidence from systematic reviews in order to formulate conclusions to support evidence-based decisions in clinical practice. METHODS: All Cochrane systematic reviews (CSRs), published by the Cochrane Wounds and Peripheral Vascular Diseases Groups, and that investigated therapeutic and preventive interventions, were searched in the Cochrane Database up to June 2011. Two investigators independently categorized each intervention into five levels of evidence of effect, based on size and homogeneity, and the effect size of the outcomes. RESULTS: After screening 149 CSRs, 44 relevant reviews were included. These contained 109 evidence-based conclusions: 30 on venous ulcers, 30 on acute wounds, 15 on pressure ulcers, 14 on diabetic ulcers, 12 on arterial ulcers and eight on miscellaneous chronic wounds. Strong conclusions could be drawn regarding the effectiveness of: therapeutic ultrasonography, mattresses, cleansing methods, closure of surgical wounds, honey, antibiotic prophylaxis, compression, lidocaine-prilocaine cream, skin grafting, antiseptics, pentoxifylline, debridement, hyperbaric oxygen therapy, granulocyte colony-stimulating factors, prostanoids and spinal cord stimulation. CONCLUSION: For some wound care interventions, robust evidence exists upon which clinical decisions should be based.

The role of vitamin C in pneumonia and COVID-19 infection in adults with European ancestry: a Mendelian randomisation study.

BACKGROUND: High dose vitamin C infusion has been proposed to treat critically ill patients, including patients with pneumonia and severe COVID-19. However, trials have shown mixed findings. Here we assessed the unconfounded associations of vitamin C with COVID-19 and pneumonia using the Mendelian randomisation approach. METHODS: This is a separate-sample Mendelian randomisation study using publicly available data. We applied single nucleotide polymorphisms (SNPs) that were associated with plasma vitamin C, in a recent genome-wide association study (GWAS) as genetic instruments to the GWAS of severe COVID-19, COVID-19 hospitalisation and any infection in the COVID-19 host genetics initiative and the GWAS of pneumonia in the UK Biobank, to assess whether people with genetically predicted higher levels of plasma vitamin C had lower risk of severe COVID-19 and pneumonia. RESULTS: Genetically predicted circulating levels of vitamin C was not associated with susceptibility to severe COVID-19, COVID-19 hospitalisation, any COVID-19 infection nor pneumonia. Similar results were obtained when a weighted median and MR-Egger methods were used. CONCLUSIONS: Mendelian randomisation analysis provided little evidence for an association of genetically predicted circulating levels of vitamin C with COVID-19 or pneumonia and thus our findings provided little support to the use of vitamin C in prevention and treatment in these patients, unless high dose vitamin C infusion has therapeutic effects via different biological pathways.

Economic evaluation of a randomized controlled trial of ultrasound therapy for hard-to-heal venous leg ulcers.

BACKGROUND: A pragmatic, multicentre randomized controlled trial (VenUS III) was conducted to determine whether low-dose ultrasound therapy increased the healing rate of hard-to-heal leg ulcers. This study was a cost-effectiveness analysis of the trial data. METHODS: Cost-effectiveness and cost-utility analyses were conducted alongside the VenUS III trial, in which patients were randomly allocated to either ultrasound treatment administered weekly for 12 weeks along with standard care, or standard care alone. The time horizon was 12 months and based on the UK National Health Service (NHS) perspective. RESULTS: The base-case analysis showed that ultrasound therapy added to standard care was likely to be more costly and provide no extra benefit over standard care alone. Individuals who received ultrasound treatment plus standard care took a mean of 14.7 (95 per cent confidence interval - 32.7 to 56.8) days longer to heal, had 0.009 (-0.042 to 0.024) fewer quality-adjusted life years and had higher treatment costs by £ 197.88 (-35.19 to 420.32). Based on these point estimates, ultrasound therapy plus standard care for leg ulcers was dominated by standard care alone. The analysis of uncertainty showed that this treatment strategy is unlikely to be cost-effective. CONCLUSION: Ultrasound treatment was not cost-effective for hard-to-heal leg ulcers and should not be recommended for adoption in the NHS.

Breakfast frequency inversely associated with BMI and body fatness in Hong Kong Chinese children aged 9-18 years.

The present study assessed the relationship between breakfast frequency and measures of obesity in Hong Kong Chinese children aged 9-18 years. A total of 11,570 children (50 % boys) underwent anthropometric measurements and completed a simple self-administered dietary behaviour questionnaire. Their parents completed a questionnaire providing demographic information. Breakfast frequency was assessed by a single question, 'How many days over the past week did you have breakfast?' Children were categorised into three groups: skippers (ate breakfast 0-2 times/week); semi-skippers (ate breakfast 3-4 times/week); non-skippers (ate breakfast 5-7 times/week), to assess all associated characteristics. Of the 3644 primary and 7926 secondary school students, 8 % (8·7 % of boys and 6·9 % of girls) and 14 % (14 % of boys and 15 % of girls), respectively, were breakfast skippers. The prevalence of obesity among breakfast skippers, semi-skippers and non-skippers was, respectively, 9·8, 10·6 and 3·8 % (P < 0·001) for primary school students and 3·9, 3·1 and 2·4 % (P < 0·001) for secondary school students. The 12 % of Hong Kong children aged 9-18 years who skipped breakfast had higher BMI, BMI z-scores and percentage of body fat (PBF) than their counterparts. The dose effects of breakfast frequency (unstandardised regression coefficient, P < 0·001) on BMI and PBF were, respectively, -0·125 kg/m2 and -0·219 % for boys and -0·165 kg/m2 and -0·353 % for girls, adjusting for physical activity per additional breakfast meal per week. Further study is recommended to elucidate whether regular breakfast consumption may have a role in the prevention of childhood obesity.

Implications of using World Health Organization growth reference (2007) for identifying growth problems in Hong Kong children aged 6 to 18 years.

OBJECTIVE: To evaluate the implications of replacing Hong Kong's 1993 growth references (HK1993) with the World Health Organization's 2007 references (WHO2007) for children aged 6 to 18 years. DESIGN: Cross-sectional study. SETTING: Thirty-six randomly selected primary and secondary schools in Hong Kong. PARTICIPANTS: A total of 14 842 children and adolescents aged 6 to 18 years in Hong Kong during 2005/06. MAIN OUTCOME MEASURES: Creation of age-specific z-scores for height, weight, and body mass index relative to HK1993 and WHO2007 references. RESULTS: Use of WHO2007 instead of HK1993 could classify an additional 1.4% children aged 6 to 10 years and 2.8% children aged 11 to 18 years as having a short stature. Using WHO2007, respective proportions that could be classified as underweight and obese increased by 3.5% and 2.1% among children aged 6 to 10 years, and 5.5% and 1.6% among children aged 11 to 18 years. CONCLUSIONS: Use of WHO2007 could increase clinical workload and patient and parent anxiety by 'over-diagnosing' short stature and underweight. Although WHO2007 may have a role in international comparative research, retention of HK1993 would seem appropriate from a clinical perspective.

Acute gastroenteritis in Hong Kong: a population-based telephone survey.

A population-based telephone survey of acute gastroenteritis (AG) was conducted in Hong Kong from August 2006 to July 2007. Study subjects were recruited through random digit-dialing with recruitments evenly distributed weekly over the 1-year period. In total, 3743 completed questionnaires were obtained. An AG episode is defined as diarrhoea >or=3 times or any vomiting in a 24-h period during the 4 weeks prior to interview, in the absence of known non-infectious causes. The prevalence of AG reporting was 7%. An overall rate of 0.91 (95% CI 0.81-1.01) episodes per person-year was observed with women having a slightly higher rate (0.94, 95% CI 0.79-1.08) than men (0.88, 95% CI 0.73-1.04). The mean duration of illness was 3.6 days (S.D.=5.52). Thirty-nine percent consulted a physician, 1.9% submitted a stool sample for testing, and 2.6% were admitted to hospital. Of the subjects aged >or=15 years, significantly more of those with AG reported eating raw oysters (OR 2.4, 95% CI 1.3-4.4), buffet meals (OR 1.8, 95% CI 1.3-2.5), and partially cooked beef (OR 1.8, 95% CI 1.2-2.7) in the previous 4 weeks compared to the subjects who did not report AG. AG subjects were also more likely to have had hot pot, salad, partially cooked or raw egg or fish, sushi, sashimi, and 'snacks bought at roadside' in the previous 4 weeks. This first population-based study on the disease burden of AG in Asia showed that the prevalence of AG in Hong Kong is comparable to that experienced in the West. The study also revealed some 'risky' eating practices that are more prevalent in those affected with AG.

Vascular lesions in pigs experimentally infected with porcine circovirus type 2 serogroup B.

Vasculitis is a hallmark lesion of the severe form of systemic porcine circovirus-associated disease (PCVAD). In 2 experimental studies with porcine circovirus type 2 serogroup b (PCV2b), 2 pigs developed fatal PCVAD with acute vasculitis, and 5 related pigs developed chronic lymphohistiocytic and plasmacytic peri- and endarteritis. Five of these pigs (1 with acute vasculitis and 4 with chronic vasculitis) had also been inoculated with bovine viral diarrhea virus type 1 (BVDV1) or BVDV1-like virus. Vascular lesions were similar, independent of whether pigs had been inoculated singly with PCV2b or dually with PCV2b and BVDV1 or BVDV1-like virus. The acute vasculitis was accompanied by marked pulmonary and mesenteric edema and pleural effusion. In situ hybridization demonstrated abundant intracytoplasmic porcine circovirus type 2 (PCV2) nucleic acid in endothelial, smooth muscle-like, and inflammatory cells within and around affected arteries. The pigs with lymphohistiocytic and plasmacytic vasculitis had lesions of systemic PCVAD, including multisystemic lymphoplasmacytic and histiocytic or granulomatous inflammation. PCV2 nucleic acid was detected in renal tubule epithelial cells, mononuclear inflammatory cells, and rare endothelial cells in noninflamed vessels in multiple tissues of these animals. The 2 pigs with acute vasculitis had no PCV2-specific antibodies (or a low titer of), whereas the pigs with lymphohistiocytic and plasmacytic vasculitis developed high antibody titers against this virus. These observations suggest that (1) acute vasculitis observed in the current studies is directly caused by PCV2b, (2) chronic vasculitis may in part be mediated by the subsequent immune response, and (3) host factors and viral strain may both contribute to vasculitis in animals infected with PCV2b.