Unhealthy landscapes: policy recommendations on land use change and infectious disease emergence

Anthropogenic land use changes drive a range of infectious disease outbreaks and emergence events and modify the transmission of endemic infections. These drivers include agricultural encroachment, deforestation, road construction, dam building, irrigation, wetland modification, mining, the concentration or expansion of urban environments, coastal zone degradation, and other activities. These changes in turn cause a cascade of factors that exacerbate infectious disease emergence, such as forest fragmentation, disease introduction, pollution, poverty, and human migration. The Working Group on Land Use Change and Disease Emergence grew out of a special colloquium that convened international experts in infectious diseases, ecology, and environmental health to assess the current state of knowledge and to develop recommendations for addressing these environmental health challenges. The group established a systems model approach and priority lists of infectious diseases affected by ecologic degradation. Policy-relevant levels of the model include specific health risk factors, landscape or habitat change, and institutional (economic and behavioral) levels. The group recommended creating Centers of Excellence in Ecology and Health Research and Training, based at regional universities and/or research institutes with close links to the surrounding communities. The centers' objectives would be 3-fold: a) to provide information to local communities about the links between environmental change and public health ; b) to facilitate fully interdisciplinary research from a variety of natural, social, and health sciences and train professionals who can conduct interdisciplinary research ; and c) to engage in science-based communication and assessment for policy making toward sustainable health and ecosystems.

Virulence determinants of infectious bursal disease virus

The very virulent (vv) pathotype of infectious bursal disease virus (IBDV) has spread rapidly throughout Europe, Asia, and the Middle East. Although Australia is currently unaffected, there remains the potential for incursion of an exotic isolate. The aim of this study was to identify putative virulence determinants of IBDV to facilitate the development of improved diagnostic assays for detection and characterisation of vvIBDV isolates. Sequencing of Indonesian vvIBDV Tasik94 revealed a unique substitution [ A�¨S222] in the hypervariable region (HVR) of viral protein (VP) VP2, which did not appear to impinge on virulence or antigenicity. Phylogenetic analyses indicated that Tasik94 was closely related to Asian and European vvIBDV strains. Extensive alignment of deduced protein sequences across the HVR of VP2 identified residuesI242 I256 and I294 as putative markers of the vv phcnotype. Comparison of the pathology induced by mildly-virulent Australian IBDV 002/73 and Indonesian vvIBDV Tasik94, revealed that histological lesions in the spleen, thymus and bone marrow were restricted to Tasik94-infected birds, suggesting the enhanced pathogenicity of vvIBDV might be attributed to replication in non-bursal lymphoid organs. The biological significance of the VP2 HVR in virulence was assessed using recombinant viruses generated by reverse genetics. Both genomic segments of Australian IBDV 002/73, and recombinant segment A constructs in which the HVR of 002/73 was replaced with the corresponding region of either tissue culture-adapted virus or vvIBDV (Tasik94), were cloned behind T7 RNA polymerase promoter sequences. In vitro transcription/translation of each construct resulted in expression of viral proteins. Co-transfection of synthetic RNA transcripts initiated replication of both tissue culture-adapted parental and recombinant viruses, however attempts to rescue non-adapted viruses in specific-pathogen-free (SPF) chickens were unsuccessful. Nucleotide sequence variation in the HVR of VP2 was exploited for the development of a new diagnostic assay to rapidly detect exotic IBDV isolates, including vvIBDV, using reverse transcription polymerase chain reaction (RT-PCR) amplification and Bmrl restriction enzyme digestion. The assay was capable of differentiating between endemic and exotic IBDV in 96% of 105 isolates sequenced to date.

Real-time early infectious outbreak detection systems using emerging technologies

The use of emerging technologies ( such as RFID - Radio Frequency Identification and remote sensing) can be employed to reduce health care costs and also to facilitate the automatic streamlining of infectious disease outbreak detection and monitoring processes in local health departments. It can assist medical practitioners with fast and accurate diagnosis and treatments. In this paper we outline the design and application of a real-time RFID and sensor-base Early Infectious (e.g., cholera) Outbreak Detection and Monitoring (IODM) system for health care.

Teachers' risk perception and needs in addressing infectious disease outbreak

The outbreak of the Influenza A (H1N1) virus has led to numerous precautionary school closures in several countries. No research is available on the school teachers’ perceptions as a health protective resource in controlling communicable disease outbreaks. The purposes of this study were to examine the risk perception, the perceived understanding of preventive measures and contingency plans, and the needs of school teachers before the imminent outbreak of H1N1. This survey was conducted with 1,169 Hong Kong school teachers before school closures due to the H1N1 outbreak. The results showed that the teachers were well aware of H1N1 but were still worried about the spread of H1N1 infection. The teachers’ worries depended on their psychological reaction, the adequacy of the control measures, government support in providing infectious disease knowledge, perceived understanding of preventive measures and contingency plans, students and parents’ awareness, and the need for support from health professionals.

Use of ultraviolet C (UVC) radiation to inactivate infectious hematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV) in fish processing plant effluent

We determined the stability of infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicemia virus (VHSV) suspended in either fish processing plant effluent blood water (EBW) or culture media and examined the effectiveness of UVC radiation to inactivate IHNV and VHSV suspended in both solutions. Without exposure to UVC, IHNV and VHSV were maintained in 4°C blood water for up to 48 hours without significant reduction in virus titer. However when exposed to UVC radiation using a low pressure mercury vapour lamp collimated beam, IHNV and VHSV were inactivated, and the efficacy of UVC radiation was dependent upon the solution and virus type being treated. A 3-log reduction for VHSV and IHNV in culture media was achieved at 3.28 and 3.84 mJ cm-2, respectively. The UV dose needed for a 3-log reduction of VHSV in EBW was 3.82 mJ cm-2. However, exposure of IHNV in EBW to the maximum UVC dose tested (4.0 mJ cm-2) only led to a 2.26-log-reduction. Factors such as particle size, and possible association of viruses with suspended EBW particulate, were not investigated in this study, but may have contributed to the difference in UVC effectiveness. Future work should emphasize improved filtration methods prior to UV treatment of processing plant EBW at an industrial scale.

Nano-lactoferrin in diagnostic, imaging and targeted delivery for cancer and infectious diseases

Lactoferrin (Lf) is a natural occurring iron binding protein present in many mammalian excretions and involved in various physiological processes. Lf is used in the transport of iron along with other molecules and ions from the digestive system. However its the modulatory functions exhibited by Lf in connection to immune response, disease regression and diagnosis that has made this protein an attractive therapeutic against chronic diseases. Further, the exciting potentials of employing nanotechnology in advancing drug delivery systems, active disease targeting and prognosis have also shown some encouraging outcomes. This review focuses on the role of Lf in diagnosing infection, cancer, neurological and inflammatory diseases and the recent nanotechnology based strategies.

Direct processing of clinically relevant large volume samples for the detection of sexually transmitted infectious agents from urine on a microfluidic device

Urine is a preferred specimen for nucleic acid-based detection of sexually transmitted infections (STIs) but represents a challenge for microfluidic devices due to low analyte concentrations. We present an extraction methodology enabling rapid on-chip nucleic acid purification directly from clinically relevant sample volumes up to 1 ml and subsequent PCR amplification detection.

Managing the risks from new and emerging infectious disease: the 'one health' paradigm

The global risk from new and emerging infectious diseases continues to grow with recognition that, for the most part, the pathogens involved emerge from animals to infect humans. Recognizing the complexity of these interactions and the need for a strong interdisciplinary approach to effectively manage these risks, new partnerships are being forged under the general umbrella of 'one health'. Involving human health, animal health, and environmental health exponents, solutions are sought for how to prevent as well as respond to the threats. But is this approach working? Whilst a number of key meetings continue to be held under the One Health umbrella, are we really seeing measureable progress in risk prevention and mitigation? Focusing research on the drivers for emergence, on modeling the risks, on improved diagnostics, and on targeted vaccines could considerably enhance our ability to prevent and respond. Ensuring the uptake and applications of new diagnostics and vaccines will be the key to prevention and response, but achieving this will require policies that drive further the One Health collaborations. Such policies should ensure that scant available resources are targeted toward the identified outcomes through research delivery and uptake, and that we genuinely work as "one world" in tackling the very real risks we face

Measuring underreporting and under-ascertainment in infectious disease datasets: a comparison of methods

 Background: Efficient and reliable surveillance and notification systems are vital for monitoring public health and disease outbreaks. However, most surveillance and notification systems are affected by a degree of underestimation (UE) and therefore uncertainty surrounds the 'true' incidence of disease affecting morbidity and mortality rates. Surveillance systems fail to capture cases at two distinct levels of the surveillance pyramid: from the community since not all cases seek healthcare (under-ascertainment), and at the healthcare-level, representing a failure to adequately report symptomatic cases that have sought medical advice (underreporting). There are several methods to estimate the extent of under-ascertainment and underreporting. Methods. Within the context of the ECDC-funded Burden of Communicable Diseases in Europe (BCoDE)-project, an extensive literature review was conducted to identify studies that estimate ascertainment or reporting rates for salmonellosis and campylobacteriosis in European Union Member States (MS) plus European Free Trade Area (EFTA) countries Iceland, Norway and Switzerland and four other OECD countries (USA, Canada, Australia and Japan). Multiplication factors (MFs), a measure of the magnitude of underestimation, were taken directly from the literature or derived (where the proportion of underestimated, under-ascertained, or underreported cases was known) and compared for the two pathogens. Results: MFs varied between and within diseases and countries, representing a need to carefully select the most appropriate MFs and methods for calculating them. The most appropriate MFs are often disease-, country-, age-, and sex-specific. Conclusions: When routine data are used to make decisions on resource allocation or to estimate epidemiological parameters in populations, it becomes important to understand when, where and to what extent these data represent the true picture of disease, and in some instances (such as priority setting) it is necessary to adjust for underestimation. MFs can be used to adjust notification and surveillance data to provide more realistic estimates of incidence. © 2014 Gibbons et al.; licensee BioMed Central Ltd.

Effective coordination and management of emerging infectious diseases in wildlife populations

A transdisciplinary, One Health approach is proposed for the coordination of wildlife health diagnostics, research, and policy development. In some countries, considerable effort has been made to establish specific activities including surveillance and integration of wildlife health within diagnostic and research laboratories. We suggest that some of these activities can be improved and many countries still require national structures to deal with wildlife disease investigation and management. We also suggest that scientists in this field should actively engage with national and international organizations and conferences to influence the development of policy, diagnostics, research, and management of emerging wildlife diseases.

Wildlife infectious disease dynamics in the context of seasonality and bird migration

The thesis contains chapters that elucidate questions with regards to wildlife infectious disease dynamics - avian influenza in particular - and how those dynamics are affected by seasonality and avian migration.

Australasian Society of Infectious Diseases updated guidelines for the management of Clostridium difficile infection in adults and children in Australia and New Zealand

The incidence of Clostridium difficile infection (CDI) continues to rise, whilst treatment remains problematic due to recurrent, refractory and potentially severe nature of disease. The treatment of C. difficile is a challenge for community and hospital-based clinicians. With the advent of an expanding therapeutic arsenal against C. difficile since the last published Australasian guidelines, an update on CDI treatment recommendations for Australasian clinicians was required. On behalf of the Australasian Society of Infectious Diseases, we present the updated guidelines for the management of CDI in adults and children.