Parasitic and parachute research in global health

Global health advocates often speak the language of eradication. It is reassuring to see the Editors of The Lancet Global Health turn their attention to another eradication effort:that of so-called parachute researchers and parasitic research (June Issue). The Editors raise the important issue of exploitative research, from which individuals from predominantly high-income countries extract data and knowledge from predominantly low-income and middle-income countries without due acknowledgement of local partners and collaborators

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.The study was funded by the Commonwealth Department of Health, and study conduct was overseen by a committee comprised of representatives from Australian government agencies and departments

The Risk of Reported Cryptosporidiosis in Children Aged < 5 Years in Australia is Highest in Very Remote Regions

The incidence of cryptosporidiosis is highest in children <5 years, yet little is known about disease patterns across urban and rural areas of Australia. In this study, we examine whether the risk of reported cryptosporidiosis in children <5 years varies across an urban-rural gradient, after controlling for season and gender. Using Australian data on reported cryptosporidiosis from 2001 to 2012, we spatially linked disease data to an index of geographic remoteness to examine the geographic variation in cryptosporidiosis risk using negative binomial regression. The Incidence Risk Ratio (IRR) of reported cryptosporidiosis was higher in inner regional (IRR 1.4 95% CI 1.2-1.7, p < 0.001), and outer regional areas (IRR 2.4 95% CI 2.2-2.9, p < 0.001), and in remote (IRR 5.2 95% CI 4.3-6.2, p < 0.001) and very remote (IRR 8.2 95% CI 6.9-9.8, p < 0.001) areas, compared to major cities. A linear test for trend showed a statistically significant trend with increasing remoteness. Remote communities need to be a priority for future targeted health promotion and disease prevention interventions to reduce cryptosporidiosis in children <5 years

Foodborne disease outbreaks in Australia 2001-2009

BACKGROUND: Analysis of surveillance data from foodborne disease outbreaks can help identify high-risk aetiological agents, food vehicles and settings. This information may help prevent future illness by informing the development of public health policy

Clostridium difficile classification overestimates hospital acquired infections

BACKGROUND Clostridium difficile infections are common among hospitalised patients, with some infections acquired in hospital and others in the community. International guidelines classify cases as hospital-acquired if symptom onset occurs >2 days after admission. This classification informs surveillance and infection control, but has not been verified by empirical or modelling studies. AIMS To assess current classification of C. difficile acquisition using a simulation model as a gold standard. METHODS We simulated C. difficile transmission in a range of hospital scenarios. We calculated the sensitivity, specificity and precision of classifications that use cut-offs ranging from 0.25 hours to 40 days. We identified the optimal cut-off that correctly estimated the proportion of cases that were hospital acquired and the balanced cut-off that had equal sensitivity and specificity. FINDINGS The recommended two-day cut-off overestimated the incidence of hospital-acquired cases in all scenarios and by >100% in the base scenario. The two-day cut-off had good sensitivity (96%) but poor specificity (48%) and precision (52%) to identify cases acquired during the current hospitalisation. A five-day cut-off was balanced and a six-day cut-off was optimal in the base scenario. The optimal and balanced cut-offs were more than two days for nearly all scenarios considered (ranges four to nine days and two to eight days). CONCLUSIONS Current guidelines for classifying C. difficile infections overestimate the proportion of cases acquired in hospital in all model scenarios. To reduce misclassification bias, an infection should be classified as being acquired prior to admission if symptoms begin within five days of admission

Modelling diverse sources of Clostridium difficile in the community: importance of animals, infants and asymptomatic carriers

Clostridium difficile infections (CDIs) affect patients in hospitals and in the community, but the relative importance of transmission in each setting is unknown. We developed a mathematical model of C. difficile transmission in a hospital and surrounding community that included infants, adults, and transmission from animal reservoirs. We assessed the role of these transmission routes in maintaining disease and evaluated the recommended classification system for hospital and community-acquired CDIs.This work was supported by an Australian National Health and Medical Council Senior Research Fellowship [#1058878 to A.C.A.C.] and an Australian Government Research Training Program Scholarship to A.M

Sequelae of foodborne Illness caused by 5 pathogens, Australia, Circa 2010

In Australia circa 2010, 4.1 million (90% credible interval [CrI] 2.3–6.4 million) episodes of foodborne gastroenteritis occurred, many of which might have resulted in sequelae. We estimated the number of illnesses, hospitalizations, and deaths from Gu

Reported waterborne outbreaks of gastrointestinal disease in Australia are predominantly associated with recreational exposure

Objective: To examine the frequency and circumstances of reported waterborne outbreaks of gastroenteritis in Australia. Method: Examination of data reported to OzFoodNet between 2001 and 2007. Results: During these seven years, 6,515 gastroenteritis outbreaks were reported to OzFoodNet, most of which were classifed as being transmitted person-to-person or from an unknown source. Fifty-four (0.83%) outbreaks were classifed as either 'waterborne' or 'suspected waterborne', of which 78% (42/54) were attributed to recreational water and 19% (10/54) to drinking water. Of the drinking water outbreaks, implicated pathogens were found on all but one occasion and included Salmonella sp. (fve outbreaks), Campylobacter jejuni (three outbreaks) and Giardia (one outbreak). Conclusions: There have been few waterborne outbreaks detected in Australia, and most of those reported have been associated with recreational exposure. However, there are difficulties in identifying and categorising gastroenteritis outbreaks, as well as in obtaining microbiological and epidemiological evidence, which can result in misclassifcation or underestimation of water-associated events. Implications: Gastroenteritis surveillance data show that, among reported waterassociated gastroenteritis outbreaks in Australia, recreational exposure is currently more common than a drinking water source. However, ongoing surveillance for waterborne outbreaks is important, especially as drought conditions may necessitate replacement of conventional drinking water supplies with alternative water sources, which could incur potential for new health risks

Modelling diverse sources of Clostridium difficile in the community: importance of animals, infants and asymptomatic carriers

Clostridium difficile infections (CDIs) affect patients in hospitals and in the community, but the relative importance of transmission in each setting is unknown. We developed a mathematical model of C. difficile transmission in a hospital and surrounding community that included infants, adults, and transmission from animal reservoirs. We assessed the role of these transmission routes in maintaining disease and evaluated the recommended classification system for hospital and community-acquired CDIs. The reproduction number in the hospital was <1 (range: 0.16-0.46) for all scenarios. Outside the hospital, the reproduction number was >1 for nearly all scenarios without transmission from animal reservoirs (range: 1.0-1.34). However, the reproduction number for the human population was 3.5-26.0%) of human exposures originated from animal reservoirs. Symptomatic adults accounted for <10% transmission in the community. Under conservative assumptions, infants accounted for 17% of community transmission. An estimated 33-40% of community-acquired cases were reported but 28-39% of these reported cases were misclassified as hospital-acquired by recommended definitions. Transmission could be plausibly sustained by asymptomatically colonized adults and infants in the community or exposure to animal reservoirs, but not hospital transmission alone. Underreporting of community-onset cases and systematic misclassification underplays the role of community transmission