Modelling The Effects Of Immunity On Influenza Transmission - Implications For Prevention And Vaccine Development
Funder
National Health and Medical Research Council
Funding Amount
$275,767.00
Summary
There is uncertainty about how many people can be infected by a single person with influenza at the start of an outbreak. Some data suggest that a single generation of transmission can infect 10-20 other people. With such a rate of growth (ie 10-20 fold every 3 days) the spread of an influenza outbreak is virtually unstoppable. Other data suggest that each person with influenza infects less than 2 other people on average. With such a lower rate of growth, control would be more feasible. Our proj ....There is uncertainty about how many people can be infected by a single person with influenza at the start of an outbreak. Some data suggest that a single generation of transmission can infect 10-20 other people. With such a rate of growth (ie 10-20 fold every 3 days) the spread of an influenza outbreak is virtually unstoppable. Other data suggest that each person with influenza infects less than 2 other people on average. With such a lower rate of growth, control would be more feasible. Our project will use data from historic and contemporary outbreaks of influenza and build mathematical models to explain the rate of growth of an influenza outbreak in terms of: 1. The proportion of people exposed to influenza who do not become ill (although there can be evidence of infection if careful studies are made). This proportion is about 33%. 2. The proportion of people who are protected from influenza by immunity, whether induced by vaccination or by past exposure to natural influenza infection (this can vary from 0% in isolated populations which have not seen influenza for many years up to 80 or 90% in urbanised populations that are exposed to influenza almost every season). 3. Different rates of contact between different people and groups of people - some may be exposed so often that their immunity is boosted regularly without them becoming severely ill; others, living in more isolated circumstances, may be rarely exposed, but when they are, they are more likely to become severely ill. 4. The effects of influenza vaccine in inducing protective immunity - it is well known that there is good protection if the vaccine is well matched to the circulating virus. 5. The effects of live virus infection in inducing (short-lived) protection against a wider range of influenza viruses. Our model results will be used to guide vaccine design and pandemic planning.Read moreRead less
Using Mathematical Models To Assess The Impact Of Interventions To Reduce Sexually Transmitted Infections In Australia
Funder
National Health and Medical Research Council
Funding Amount
$562,276.00
Summary
Sexually transmitted infections (STIs) are an increasing public health problem in Australia. Australia's recent National Transmissible Infections Strategy identified chlamydia control, STI prevention in gay men and STIs in Aboriginal and Torres Strait Islander communities as priority areas. We propose to develop mathematical models of STI transmission and use these to help understand and identify the most cost-effective interventions to reduce the impact of STIs on Australian populations.
Mathematical Modelling Of Bacterial Carriage In Children
Funder
National Health and Medical Research Council
Funding Amount
$421,746.00
Summary
Children exposed to larger numbers of other children are at risk of persistent bacterial infections. Such circumstances explain the high rates of ear and chest infections, and skin sores seen in children in historical times. Changing social circumstances (smaller families, better housing, nutrition and hygiene), as well as the introduction of antibiotics, explain the decline of such infections in affluent communities since the early 20th century. However, even today, in affluent countries, child ....Children exposed to larger numbers of other children are at risk of persistent bacterial infections. Such circumstances explain the high rates of ear and chest infections, and skin sores seen in children in historical times. Changing social circumstances (smaller families, better housing, nutrition and hygiene), as well as the introduction of antibiotics, explain the decline of such infections in affluent communities since the early 20th century. However, even today, in affluent countries, children attending group child care are at high risk of ear infections. As many bacteria are resistant, antibiotics are now much less effective than when they were first introduced. Furthermore, there is a continuing load of infection for children in Aboriginal communities, in PNG and other developing countries, causing hearing loss, chronic respiratory problems, and heart disease and renal disease in later life. Using data previously collected from other studies in Indigenous communities and children in child care, mathematical models allow us to ask what if?, and answer important public health questions: 1. What environmental and public health measures can reduce the cycle of cross-infection in child-care and high-risk populations? 2. What coverage rates with pneumococcal vaccine will eliminate the vaccine-specific bacteria from child care centres, from the wider community, and from high risk populations? 3. Will infections with bacteria not covered by vaccine then increase? 4. Will the resistant bacteria tend to disappear if antibiotic use is restricted? 5. Under what circumstances will antibiotics help to control infection? The modelling will promote understanding of the social and health costs of bacterial infection in Aboriginal communities and child care and use educational scenarios to promote uptake of the most cost-effective and socially acceptable interventions.Read moreRead less
Antagonist Of Corticotrophin Releasing Hormone As Therapeutic Agents For The Prevention Of Premature Birth In Humans
Funder
National Health and Medical Research Council
Funding Amount
$376,650.00
Summary
In developed countries the most common cause of the death of a newborn baby is premature delivery. Pre-term delivery remains the greatest cause of neonatal mortality in the western world and a major consumer of health dollars (approx. $5-7B per year in the US alone). However, a delay in the onset of labour from 20 to 25 weeks has been shown to result in a 55% greater probability of infant survival (550 fewer deaths per 1000). This project will allow: The development of new drugs that will allow ....In developed countries the most common cause of the death of a newborn baby is premature delivery. Pre-term delivery remains the greatest cause of neonatal mortality in the western world and a major consumer of health dollars (approx. $5-7B per year in the US alone). However, a delay in the onset of labour from 20 to 25 weeks has been shown to result in a 55% greater probability of infant survival (550 fewer deaths per 1000). This project will allow: The development of new drugs that will allow the extension of pregnancy term The development of protocols that will in turn reduce neonatal mortality. Additionally we believe that these new agents will be useful in preventing the onset of labour after fetal surgery. Currently there are no effective treatments capable of substantially changing delivery dates. Available therapeutics delay the onset of labour, at best, 24 hours. However, recent exciting results from our laboratories show that rising concentrations of the placental peptide Corticotrophin Releasing Hormone (CRH) are associated with the onset of labour. Further, we have also delayed the onset of labour in pregnant sheep by infusing a relatively insoluble CRH antagonist into the sheep fetus. Labour commenced ONLY AFTER the drug was withdrawn from the mother. This project builds upon an interdisciplinary team: medicinal chemists, molecular modellers, pharmacologists and endocrinologists, to further develop an exciting Australian discovery. Successful completeion of this research will, for the first time, allow the control of pregnancy duration MAXIMISING the benefits to mother and child, reducing mortality and later life morbidities typically associated with premature birth.Read moreRead less
Modelling The Interaction Between Sexually Transmitted Infections And HIV Transmission To Inform Public Health Policy
Funder
National Health and Medical Research Council
Funding Amount
$543,624.00
Summary
Other sexually transmitted infections (STIs) increase the risk of acquiring or transmitting HIV. Using mathematical models the population level effects of this increased risk will be investigated. This work will inform the design of effective and efficient STI treatment programs that aim to reduce the number of HIV infections in Australian gay men, prevent HIV epidemics in Aboriginal and Torres Strait Island communities, and slow the growth of HIV in Papua New Guinea.
Physical, Lifestyle And Psychosocial Determinants Of Spinal Pain Development In Adolescents
Funder
National Health and Medical Research Council
Funding Amount
$682,800.00
Summary
This project aims to understand the development of back and neck pain in adolescence. By the age of 16 around half of all adolescents have suffered back pain and one third have suffered neck pain. For many adolescents this pain is disabling and over a third of sufferers miss school, miss recreation and seek medical help. The current understanding of back and neck pain in adolescence is quite limited - restricting the effectiveness of initiatives to prevent adolescents having to suffer spinal pai ....This project aims to understand the development of back and neck pain in adolescence. By the age of 16 around half of all adolescents have suffered back pain and one third have suffered neck pain. For many adolescents this pain is disabling and over a third of sufferers miss school, miss recreation and seek medical help. The current understanding of back and neck pain in adolescence is quite limited - restricting the effectiveness of initiatives to prevent adolescents having to suffer spinal pain and of treatment of those adolescents unlucky enough to have an episode. Better understanding and interventions for adolescent spinal pain will also have longer term implications by reducing adult spinal pain. Four out of 5 adults will experience spinal pain. In the USA treating adult back pain is the 4th largest health care cost. Many adults with chronic back pain had their first episode during adolescence. A better understanding of spinal pain in adolescence may help prevent it developing into a lifelong disability. We will collect information from 2,000 adolescents on their experience of back and neck pain and on potential physical, lifestyle and psychosocial risk factors. We believe factors such as their posture, muscle capacity, TV and computer use, mental health and social situation all combine to influence whether a person develops back or neck pain. The project is unique as it will not only collect a broad range of information during adolescence, but will also make use of a large database of health, developmental and psychosocial information already collected from these children since birth. With a better understanding of the development of spinal pain we will be able to develop guidelines to help prevent these problems. We will also be able to develop better treatment plans for sub-groups of adolescents with a particular combination of risk factors. Together these initiatives will assist in understanding and breaking the pathway to chronic spinal pain.Read moreRead less
A reduced capacity to recover balance following an imbalance episode contributes to the high incidence of falls in older adults. The goal of the present study is to determine how age-related differences in lower extremity neuromuscular and biomechanical properties are related to balance recovery capacity and falls incidence. A detailed understanding of this relationship is necessary for the development of efficacious exercise-based interventions for the prevention of falls.
Measuring The Productive Efficiency Of Hospitals - A Comparison Of Parametric And Non-parametric Approaches
Funder
National Health and Medical Research Council
Funding Amount
$61,815.00
Summary
In the face of rising health service costs, an ageing population, and falling private health insurance rates, the efficient use of scarce health service resources has become a central theme in health system reform. Productive (or technical) efficiency is a key aspect of health system reform - that given health services are produced with the minimum feasible amount of resources. Despite the importance of technical efficiency there have been few published studies in Australia which measure technic ....In the face of rising health service costs, an ageing population, and falling private health insurance rates, the efficient use of scarce health service resources has become a central theme in health system reform. Productive (or technical) efficiency is a key aspect of health system reform - that given health services are produced with the minimum feasible amount of resources. Despite the importance of technical efficiency there have been few published studies in Australia which measure technical efficiency in the health sector. This study will develop theoretical and empirical approaches to measuring technical efficiency in the production of hospital services using data from Victoria. Measures of hospital technical efficiency will be developed using two quantitative modelling approaches: stochastic frontier modelling and data envelopment analysis. Results will be used to investigate the impact of patient and hospital characteristics on efficiency, and to identify economies of scale and scope in the provision of hospital services. The robustness of results to changes in variables, the sample of hospitals studied, and model assumptions will be tested, and two techniques will be compared to assess their appropriateness in the health services context which has not previously been done. Criteria for assessing the approaches include the degree to which: assumptions affect the robustness of results; the techniques capture the salient features of health services production; and the techniques produce similar rankings and estimates of inefficiency. The methods used will represent a significant contribution to international knowledge of hospital efficiency measurement, and the relationships between hospital characteristics, casemix, and efficiency. The study wil provide improved measures of hospital efficiency in Victoria, and will inform debate on hospital funding policy.Read moreRead less