A Metapopulation Model of Tuberculosis Transmission with a Case Study from High to Low Burden Areas

Tuberculosis (TB) is a growing problem worldwide, especially with the emergence and high prevalence of multidrug-resistant strains. We develop a metapopulation model for TB spread, which is particularly suited to investigating transmission between areas of high and low prevalence. A case study of cross-border transmission in the Torres Strait region of Australia and Papua New Guinea (PNG) is considered and a sensitivity analysis is conducted. We find that only 6 of the 50 parameters analysed are important to the cumulative number of clinically active TB patients in the entire region. Of these, only the detection rate in PNG is found to be an important intervention parameter. We therefore give insight into the extent the area with the high burden of TB (PNG in the case study) is dominating the TB dynamics of the entire region. Furthermore, the sensitivity analysis results give insight into the data that most important to collect and refine, which is found to be data relating to the PNG parameters

Floodway Design Process Revisted

Floodways are small road structures that are meant to be overtopped by floodwater during a flood event with relatively low average recurrence interval and expected to be in complete functional stage after the flood water recedes. The severity of 2011 and 2013 flood events in Queensland damaged the floodways in the state causing a huge impact mainly to the rural community during the recovery and rehabilitation stage. Therefore, the resilience of these small critical road structures is of great importance for the survival, safety and recovery stages during such events. Using a case study region in Lockyer Valley Regional Council area, the authors found that majority of the structural damage was caused due to the heavy impact load from the boulders/logs that came with the flood water. Another aspect reviewed was the damage sustained by floodway aprons due to excessive debris loading. This is of particular concern since aprons are the most expensive component of a floodway to repair or replace. Since floodways encounter many forces throughout their service life thorough review and investigation of current design standards are required in order to improve floodway resilience. In an attempt to develop a floodway design process, this paper focusses on the analysis of two types of floodways and reports the procedure used to develop design charts. Detailed finite element analysis is demonstrated by using one type of floodway. Finally, the contribution that resulted from the structural analysis is linked with the current floodway design guide

Avian Influenza H5N1 Transmission in Households, Indonesia

BACKGROUND: Disease transmission patterns are needed to inform public health interventions, but remain largely unknown for avian influenza H5N1 virus infections. A recent study on the 139 outbreaks detected in Indonesia between 2005 and 2009 found that the type of exposure to sources of H5N1 virus for both the index case and their household members impacted the risk of additional cases in the household. This study describes the disease transmission patterns in those outbreak households. METHODOLOGY/PRINCIPAL FINDINGS: We compared cases (n = 177) and contacts (n = 496) in the 113 sporadic and 26 cluster outbreaks detected between July 2005 and July 2009 to estimate attack rates and disease intervals. We used final size household models to fit transmission parameters to data on household size, cases and blood-related household contacts to assess the relative contribution of zoonotic and human-to-human transmission of the virus, as well as the reproduction number for human virus transmission. The overall household attack rate was 18.3% and secondary attack rate was 5.5%. Secondary attack rate remained stable as household size increased. The mean interval between onset of subsequent cases in outbreaks was 5.6 days. The transmission model found that human transmission was very rare, with a reproduction number between 0.1 and 0.25, and the upper confidence bounds below 0.4. Transmission model fit was best when the denominator population was restricted to blood-related household contacts of index cases. CONCLUSIONS/SIGNIFICANCE: The study only found strong support for human transmission of the virus when a single large cluster was included in the transmission model. The reproduction number was well below the threshold for sustained transmission. This study provides baseline information on the transmission dynamics for the current zoonotic virus and can be used to detect and define signatures of a virus with increasing capacity for human-to-human transmission

Embedding cultural competence in faculty : a mixed-methods evaluation of an applied Indigenous proficiency workshop

One of the most pressing issues in Australian society is the gap between Indigenous and non-Indigenous health and life expectancies (Marmot, 2017). Australia agreed with the World Health Organisation’s 2008 Closing the Gap in a Generation report (WHO, 2008), spending approximately 5.6% of government expenditure towards ameliorating this gap (Gardiner-Garden & Simon-Davies, 2012), yet there have been only minimal positive outcomes (Alford, 2015; Gannon, 2018). In applied terms, this means Indigenous people are still dying younger (Anderson et al., 2016), scoring higher on psychological distress (Markwick, Ansari, Sullivan, & McNeil, 2015) and suffering poorer indices on all chronic diseases (e.g. Walsh & Kangaharan, 2016; Thompson, Talley, & Kong, 2017). The level of complexity involved in addressing these “wicked” or seemingly “impossible to solve” health problems is made worse by the lack of any pan-national strategic planning and/or intervention evaluation (Lokuge et al., 2017), even though there has been a plethora of programs and projects designed to improve Indigenous health (see for example, AGPC, 2016). Leaders in health and educational institutions must consider why there is a lack of progress in closing the gap in Indigenous health and life expectancies. Addressing the inequities in Indigenous health requires a determinant of health approach (Mitrou et al., 2014), as 39% of the gap in health outcomes can be explained by social determinates (AIHW, 2017; Markwick, Ansari, Sullivan, Parsons, & McNeil, 2014). The social determinant considered to most reliably predict Indigenous poor health is racism (Kelaher, Ferdinand, & Paradies, 2014; Paradies, 2006; Paradies & Cunningham, 2009; Paradies et al., 2015; Paradies, Truong, & Priest, 2014)

Free vibration behaviour of fibre composite sandwich beams with debonds

Although perfect bond between the skin and the core is a common assumption, an important issue that needs to be considered in using a composite beam or slab is the development of debonding between the skin and the core. Debonding refers to separation of skin from the core material in composite sandwiches. Although much research has been carried out to investigate dynamic behaviour of fully bonded composites, research on this aspect for debonded composites is scarce. This study concentrates on investigating the dynamic behaviour of fibre composite sandwich beams with debonds. A parametric investigation is carried out to assess the influence of various parameters of concern including length and width of the debond, location of debond, size and support conditions of the beam on the free vibration behaviour, using the finite element package Strand7. In the model developed with Strand7, rigid links and master slave links are used to connect skin and core in bonded and debonded regions respectively. Published results for free vibration behaviour for GFRP panels will first be used to compare the analytical results to validate the developed model. Furthermore a spring model is implemented between the skin and the core of debonded beams to take the probable contact conditions into account. A general reflection through the parametric investigation is that the extent of natural frequency variation with respect to debonding length increases with the order of the natural frequency. Further it is observed that the change in frequency with change in debonding length is much more significant for the full width debonding when compared to half width debonding. It is also perceived that the extent of variation of natural frequency due to debonding in composite beams depends on the degree of contact anticipated in the debonding region

The (local) disease model. S = Susceptible, L = Latently infected, N = non-infectious clinically apparent TB, I = infectious clinically apparent TB, D = Detected but not yet treated, T = undergoing Treatment but still infectious.

<p>The parameters are described in the text and summarised in the table in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0034411#pone.0034411.s001" target="_blank">File S1</a>. Here .</p

The relative sensitivities of the intervention parameters at ‘2032’.

<p>The relative sensitivities of the intervention parameters at ‘2032’.</p

Sensitivity analysis of the model parameters, comparing the relative monotonicity of the cumulative number with active TB (I+N+D+T) for all sub-populations with various parameters.

<p>‘PNG’ refers to sub-population (1,1) parameters.</p