Yingxi Chen

Incidence of acute respiratory infections in Australia

We used a national survey of 7578 randomly selected respondents in 2008-2009 to identify the period prevalence of acute respiratory infection (ARI) by season and state, and to estimate the incidence of ARI in the Australian community. A case was defined as any episode of cold or flu with at least one of the following symptoms: fever, chills, sore throat, running nose, or cough in the past 4 weeks. Frequency data were weighted to the Australian population. The response rate to the survey was 49%, and 19·9% (1505/7578) of respondents reported an ARI in the previous 4 weeks, which extrapolated to 68·9 million cases [95% confidence interval (CI) 65·1-72·7] of ARI in Australia annually. The incidence was 3·2 (95% CI 3·0-3·4) cases of ARI/person per year, and was highest in young children and lowest in older people. ARI imposes a significant burden on Australian society.

Risk factors for acute respiratory infection in the Australian community.

Objectives The objective of this study was to identify the risk factors for ARI in the Australian community. Methods We used a national survey of 7578 randomly selected respondents in 2008–2009 to identify the risk factors of ARI. A case was defined as a person experiencing cold or flu with one or more symptoms of: fever, chills, sore throat, runny nose, or cough in the previous four weeks. Results There were 19.8% (1505/7578) of respondents who reported ARI in the four weeks prior to the survey. Age was an independent risk factor for ARI, with the risk of acquiring ARI decreasing as age increased. Respondents reporting asthma (OR 1.4, 95%CI: 1.2–1.7) or having someone in their house attending childcare (OR 1.6, 95%CI: 1.2–2.1) were more likely to report ARI. Conclusions It is important to identify ways of interrupting transmission of ARI amongst children. Improving identification of risk factors will enable targeted interventions for this exceedingly common syndrome.

Clostridium difficile Infection and Risk of Colectomy in Patients with Inflammatory Bowel Disease: A Bias-adjusted Meta-analysis.

Background: Clostridium difficile infection (CDI) is a common complication of inflammatory bowel diseases (IBDs) and is associated with worse outcome. Variable rates of colectomy have been reported among IBD complicated by CDI. We conducted a systematic review and meta-analysis of studies to assess the association between CDI and colectomy among patients with IBD. Methods: The literature was systematically searched using PubMed from inception through April 2016. Studies were limited to cohort, case–control, and cross-sectional studies reporting colectomy risk stratified by CDI in patients with IBD. We estimated summary ORs and 95% CIs using the quality-effects model. Study quality was assessed using an adaptation of the Newcastle–Ottawa scale. Results: Six studies were included in the meta-analysis, comprising 8 data sets. Results from meta-analysis showed that CDI was a significant risk factor for colectomy among patients with IBD, mainly patients with ulcerative colitis, almost doubling the odds (OR 1.90; 95% CI, 1.23–2.93). There was significant heterogeneity across studies (Q = 22.02, P < 0.001; I2 = 68%). Funnel plots were grossly asymmetrical. Results of sensitivity analysis restricting studies to those reporting ulcerative colitis only and studies using laboratory tests to confirm CDI were consistent with the result from the main analysis. Conclusions: CDI is a significant risk factor for colectomy in patients with IBD. Further research is needed to investigate the attributable risks of surgery due to CDI among patients with Crohns disease.

Use of Proton Pump Inhibitors and the Risk of Hospitalization for Infectious Gastroenteritis.

Introduction To quantify the association between PPI use, type and dose and infectious gastroenteritis hospitalization in a population-based cohort of middle-aged and older adults. Methods Prospective study of 38,019 concession card holders followed up over 6 years in the Sax Institute’s 45 and Up Study. Data from the baseline questionnaire were linked to prescription medication, hospitalization, notifiable disease, cancer registry and death datasets from 2006–2012. Associations between PPI use and gastroenteritis hospitalization were examined using Cox regressions with age as the underlying time variable. Results Among 38,019 participants, the median age was 69.7 years, and 57.3% were women. Compared to non-users, current PPI users were more likely to be older, and have a higher BMI. During follow-up there were 1,982 incident gastroenteritis hospitalizations (crude rate: 12.9 per 1000 person-years, 95% CI: 12.3–13.5). PPI use was significantly associated with infectious gastroenteritis hospitalization (aHR 1.4, 95% CI: 1.2–1.5). Among current users, a dose-response relationship was observed between the average daily dose (DDD) dispensed per day and infectious gastroenteritis hospitalization (Ptrend<0.001). We also observed higher rates of infectious gastroenteritis hospitalization and greater PPI use among participants with a history of chronic bowel problems (aHR 2.2, 95% CI: 1.9–2.5). There was no difference in risk by type of PPI. Recent use of H2 receptors was not associated with gastroenteritis hospitalization. Conclusion PPI use is associated with an increased risk of infectious gastroenteritis hospitalization. Clinicians should be aware of this risk when considering PPI therapy.

Norovirus Disease in Older Adults Living in Long-Term Care Facilities: Strategies for Management

Purpose of ReviewNoroviruses are the most common cause of gastroenteritis outbreaks in long-term care facility (LTCFs). This review summarizes the most up-to-date knowledge on norovirus infection in LTCFs with the aim of identifying potential strategies for management.Recent FindingsLTCF residents are at greater risk of norovirus infection. Early identification of norovirus infection and prompt initiation of appropriate supportive therapy are required to reduce morbidity and mortality. Measures to prevent outbreaks and reduce the risk of norovirus infection in LTCFs include timely diagnosis and implementation of infection control interventions to limit virus transmission.SummaryCurrent guidelines for prevention and control are based on generic principles of infection control. Real-time reverse transcription-quantitative polymerase chain reaction assays have been the gold standard for the rapid and sensitive detection of noroviruses. With the recent breakthroughs of human norovirus in vitro culture, doors are now opened to evaluate the efficacy of environmental disinfectants and hand hygiene options. Additionally, development of licensed vaccines against noroviruses may provide another important tool for infection prevention among high-risk individuals.

A population-based longitudinal study of Clostridium difficile infection-related hospitalization in mid-age and older Australians

Clostridium difficile is the principal cause of infectious diarrhoea in hospitalized patients. We investigated the incidence and risk factors for hospitalization due to C. difficile infection (CDI) in older Australians. We linked data from a population-based prospective cohort study (the 45 and Up Study) of 266 922 adults aged ⩾45 years recruited in New South Wales, Australia to hospitalization and death records for 2006-2012. We estimated the incidence of CDI hospitalization and calculated days in hospital and costs per hospitalization. We also estimated hazard ratios (HR) for CDI hospitalization using Cox regression with age as the underlying time variable. Over a total follow-up of 1 126 708 person-years, 187 adults had an incident CDI hospitalization. The crude incidence of CDI hospitalization was 16·6/100 000 person-years, with a median hospital stay of 6 days, and a median cost of AUD 6102 per admission. Incidence increased with age and year of follow-up, with a threefold increase for 2009-2012. After adjustment, CDI hospitalization rates were significantly lower in males than females (adjusted HR 0·6, 95% confidence interval 0·4-0·7). CDI hospitalization rates increased significantly over 2009-2012. There is a need to better understand the increasing risk of CDI hospitalization in women.

Burden of Clostridium difficile infection: Associated hospitalization in a cohort of middle-aged and older adults

HighlightsCDI hospitalizations had longer hospital stay, greater costs, and higher proportion with in‐hospital deaths compared to non‐CDI hospitalization.Of patients hospitalized with CDI, 7.3% died during hospitalization.Digestive, cardiovascular, neoplastic and respiratory diseases constituted nearly half of principal diagnoses for which CDI was a secondary diagnosis. Background: Clostridium difficile is the principal cause of infectious diarrhea in hospitalized patients. The aim of this study was to describe and compare length of stay (LOS), costs, and in‐hospital deaths for C difficile infection (CDI) and non‐CDI hospitalizations, in a cohort of middle‐aged and older Australians. Methods: We used survey data from the 45 and Up Study, linked to hospitalization and death data. We calculated the average LOS and costs per hospitalization, and the proportion of in‐hospital deaths for CDI and non‐CDI hospitalizations. We then compared hospitalizations with CDI as a secondary diagnosis to non‐CDI hospitalizations by stratifying hospitalizations based on principal diagnosis and then using generalized linear models to compare LOS and in‐hospital costs, and logistic regression for in‐hospital deaths, adjusting for age and sex. Results: There were 641 CDI hospitalizations during 2006‐2012. The average LOS was 17 days; the average cost per hospitalization was AUD 12,704; and in 7.3% of admissions (47 out of 641) the patient died. After adjusting for age and sex, hospitalizations with CDI were associated with longer LOS, higher costs, and a greater proportion of in‐hospital deaths compared with hospitalizations with similar principal diagnosis but without CDI. Conclusions: CDI places additional burden on the Australian hospital system, with CDI patients having relatively lengthy hospital stays and high costs.

High incidence of hospitalisation due to infectious gastroenteritis in older people associated with poor self-rated health

Objectives To estimate the incidence and risk factors for gastroenteritis-related hospitalisations in older adults. Design Longitudinal cohort study. Participants The 45 and Up Study is a large-scale Australian prospective study of adults aged ≥45 years (mean 62.7 years) at recruitment in 2006–2009. Self-reported demographic, health and dietary information at recruitment from 265 440 participants were linked to infectious gastroenteritis hospitalisation data. Outcome measures We estimated the incidence of hospitalisation for infectious gastroenteritis, and calculated HRs using Cox regression, adjusting for sociodemographic, health and behavioural variables, with age as the underlying time variable. Results There were 6077 incident infectious gastroenteritis admissions over 1 111 000 person-years. Incidence increased exponentially with increasing age; from 2.4 per 1000 (95% CI 2.2 to 2.5) in individuals aged 45–54 years to 9.5 per 1000 (95% CI 9.2 to 9.8) in those aged 65+ years. After adjustment, hospitalisation due to infectious gastroenteritis was significantly more common in those reporting use of proton pump inhibitors (HR 1.6, 95% CI 1.5 to 1.7), and those with poorer self-rated health (HR 4.2, 95% CI 3.6 to 4.9). Conclusions Infectious gastroenteritis results in hospitalisation of approximately 1% of people ≥65 years old each year. Early recognition and supportive treatment of diarrhoea in older patients with poorer self-rated health may prevent subsequent hospitalisation.

Efficacy of Anthelminthic Drugs and Drug Combinations Against Soil-transmitted Helminths: A Systematic Review and Network Meta-analysis

Background Periodic mass distribution of benzimidazole anthelminthic drugs is the key strategy to control soil-transmitted helminths (STHs) globally. However, benzimidazoles have low efficacy against Trichuris trichiura, and there are concerns about benzimidazole resistance potentially emerging in humans. Therefore, identifying alternative drug regimens is a pressing priority. We present a systematic review and network meta-analysis comparing the efficacy of 21 different anthelminthic drug regimens, including standard, novel, and combination treatments. Methods We searched PubMed, Medline, Embase, Web of Science, and Cochrane databases and identified studies comparing anthelminthic treatments to each other or placebo. The outcomes calculated were relative risk (RR) of cure and difference in egg reduction rates (dERR). We used an automated generalized pairwise modeling framework to generate mixed treatment effects against a common comparator, the current standard treatment (single-dose albendazole). Results Our search identified 4876 studies, of which 114 were included in the meta-analysis. Results identified several drug combinations with higher efficacy than single-dose albendazole for T. trichiura, including albendazole-ivermectin (RR of cure, 3.22 [95% confidence interval {CI}, 1.84-5.63]; dERR, 0.97 [95% CI, .21-1.74]), albendazole-oxantel pamoate (RR, 5.07 [95% CI, 1.65-15.59]; dERR, 0.51 [95% CI, .50-.52]), mebendazole-ivermectin (RR, 3.37 [95% CI, 2.20-5.16]), and tribendimidine-oxantel pamoate (RR, 4.06 [95% CI, 1.30-12.64]). Conclusions There are several promising drug combinations that may enhance the impact of STH control programs on T. trichiura, without compromising efficacy against Ascaris lumbricoides and hookworm. We suggest further, large-scale trials of these drug combinations and consideration of their use in STH control programs where T. trichiura is present. International Prospective Register of Systematic Reviews Registration CRD42016050739.