Climate Change and Disease Pattern - Literature review Example

Title: Name: Institution Name: List of Content Introduction Transmission Vulnerability Factors a. Environmental Vulnerability b. Social Vulnerability c. Economical Vulnerability Health early warning systems Diagnosis Vaccination Treatment Prevention Conclusion References Introduction The imbalance between outgoing and incoming radiation in the earth atmosphere is what causes climate change. As the radiation of the sun reaches the atmosphere, some of these radiations are being absorbed by the surface of the earth and reemitted from the surface of the earth as infrared radiation (McMichael, Woodruff & Hales 2006). Infrared radiation is then absorbed by greenhouse gases-methane, carbon dioxide, and nitrous oxide. Concentration of greenhouse gases in the atmosphere has reached record levels, world temperature is rising at a fast rate and this has altered the atmosphere hydrologic cycle (IGWG 2004). Since, warmer air is able to retain more moisture than cooler air. The effect of this will cause some part of the world to have more rainfall, and some more drought, and severe weather events. Because of changing rainfall patterns and rising temperatures, climate changes in the world have an effect on the burden of infectious diseases that are transmitted by insect vectors such as mosquitoes and water that is contaminated (Currie & Jacups 2003). At higher temperatures that comes about as a results of the effect of climate changes. Insect vectors tend to be more active, for example, mosquitoes such as anopheles species that are responsible in transmitting Japanese Encephalitis (JE), will require temperatures above 16 degrees centigrade to complete their life cycles. The impact of climate changes are severe, it has resulted in the introduction of certain infectious diseases into geographical regions that were unaffected (Green 2006). For example, spread of Japanese Encephalitis (JE) into highlands, where Japanese Encephalitis (JE) disease previously did not exist. The spread of malaria is happening in region that was much wetter and warmer than usual; effect of this has resulted in high rates of death and illness, because the disease has spread into a largely non-immune population (ECU 2006). Climate changes will also the affect the spread and transmission rates vector-borne diseases. The rise in temperature due climate change has been found to affect the rate of pathogen maturation and replication within vector mosquitoes, the density of vector mosquitoes in a particular area, and increases the likelihood of infection (Green and Preston 2006). Therefore, that population that has little or no immunity to infections will be at risk (Hennessy, Pittock, Walsh, Suppiah, McInnes and Bathols 2004). In the world, the prevalence of threats to people health and diseases depend largely on region climate. Climate-related disturbances in ecological systems, while extreme temperature will result in deaths, such as changes in parasites that cause disease, will directly impact on the serious infectious diseases (Patz & Olson 2006). In addition, warm temperatures can increase water and air pollution, which in turn people health. Individual health is strongly affected by technological, social, environmental, economic and political factors. The extent in which climate change will have an impact on human health will vary by the duration and extent of exposure to climate change itself, by region, by society’s ability to cope to or adapt with the change, and by relative vulnerability of population groups (Watson, Zinyoera & Moss 1996). Transmission The growing risk of Japanese Encephalitis (JE) is considered to be caused by climate change on human health. Warmer temperature due to climate change has created those conditions that are favor vectors and germs spread such mosquitoes. Particular subtropical and warm temperate regions of far north Queensland, Australia would be more vulnerable to Japanese Encephalitis. Japanese Encephalitis (JE) virus is transmitted in a mosquito enzootic cycle and vertebrate such as pigs and birds amplifying hosts. In Queensland, Australia The viral infection rates in mosquito’s vector range from less than one per cent to three per cent. These species of mosquitoes thrive in rural Queensland where their larvae breed in ground pools. Thus all elements of the transmission cycle occur in rural areas and human infections occur principally in this setting. Because animals amplifying hosts while agricultural activities may be situated near towns or cities. Japanese Encephalitis (JE) virus is usually transmitted seasonally in most areas of Queensland. The patterns of transmission of Japanese Encephalitis (JE) virus are correlated with the abundance of vectors mosquitoes. The abundance of mosquitoes will fluctuate with the amount of rainfall experienced in a region, in some locations in Queensland, irrigation that is associated with agricultural activities is another factor that affecting the spread of vector mosquitoes, and transmission of Japanese Encephalitis (JE) virus may occur year-round. The annual incidence of Japanese Encephalitis (JE) ranges from 1 to 10 per 10,000 people, and most of the cases usually occur in children under 10 years of age. Seroprevalence studies for Japanese Encephalitis (JE) indicate exposure by adulthood (Vaughn and Hoke 2000). In Asia, about 55,000 cases of Japanese encephalitis (JE) disease are reported each year (Pittock 2003). Japanese Encephalitis (JE) virus is rampant in most part of western Pacific and Asia, but local transmission has not been observed in Europe, Africa, or the Americas. For a person travelling to the region where Japanese Encephalitis (JE) is rampant the risk of contracting the disease is very low but varies based on destination, duration, season, and activities (Vaughn and Hoke 2000). Domestic pigs that have been infected will act as amplifying hosts. Pig keeping in Queensland has been noted to be an important risk factor that helps in the transmission to people. In tropical areas of Queensland, cases of Japanese Encephalitis (JE) infections occur more sporadically and its peaks have been observed to occur during the rainy season. Migrations of birds during summers in also play a role in dispersing Japanese Encephalitis (JE) virus. International travel, accidental transportation of vectors, and human migration is of little importance since viremia in human beings is usually of short duration and low and because human beings are dead-end hosts (Smith 2004). Proximity to Papua New Guinea makes inhabitants of the Torres Strait Islands vulnerable to Japanese Encephalitis (JE) virus through wind-borne mosquitoes, also, re-establishment of the disease if the conditions become more favorable (Hennessy et el 2004). Vulnerability Factors a) Environmental Vulnerability Environmental factors that contribute in the spread of Japanese Encephalitis (JE) include chemical, physical and biological elements. Changes in physical environment have been at considerable cost to resources such as rivers and aquifers, soil and aquifers, and biodiversity. Also, materials that have been released into the environment have contributed to the issues that could have an impact on the spread of vector mosquitoes in Queensland. Environment is a principal factor that has increased the vulnerability of indigenous people being exposed to climate hazards, and the high reliance on environment by indigenous people to sustain their cultural practices and traditional livelihoods. Indigenous people living in Queensland are similarly identified. Many of these people are sensitive to direct and indirect impacts of climate change on many aspects of their lives, also their low adaptive capacity (Pittock 2003). The health concerns and needs for Indigenous people are different to that of mainstream health requirements for non-indigenous people (Pittock 2003). Many indigenous people living in Queensland are sensitive to environmental changes, and these changes have an impact on their physical and mental well-being via disturbance of their cultural practices (Smith 2004; Jackson 2005). For example, environmental changes due to climate change have affected traditional activities such as ceremonial practices, bush tucker and hunting collection and this has affected nutritional intake as well as mental health of indigenous people (Ellemor 2005). Preexisting psychological and physical factors that have been caused by poverty and dispossession has further challenge the ability of indigenous communities in Queensland to cope with health impacts of climate change (Ellemor 2005). The impact of temperature changes, along with precipitation changes, on a range of Japanese Encephalitis (JE) transmission rates tend to be very locally specific, and this will depend with a combination of many physical factors and presence of necessary ‘vector’ host such as mosquitoes or mammals or birds (Jackson 2005). In addition, increase in humidity and temperature will have an impact on the time taken for the vector mosquitoes to develop to an infectious stage (Patz & Olson 2006). In other places studies have shown Japanese Encephalitis (JE) transmission rates have a significant association with heavy rainfall. Storm surges and coastal erosion caused by floods and heavy rains on many occasion has threaten the infrastructure that is vital to emergency rescues. This has reduced the ability for emergency management agencies in Queensland to act effectively against vector mosquitoes (Jackson 2005). b) Social Vulnerability According to Blaikie et al (1994) argue that families that have access to social networks and resources are less vulnerable to diseases. Although families that are well-off may experience greater losses than the poor families. It can be argued families that are well-off are more resilient in that they are able to recover more quickly from a stimulus/stress than poor families. A number of sub-groups have been identified to be vulnerable to health impacts of climate changes (Currie & Jacups, 2003). These sub-groups that have high risk in Japanese Encephalitis (JE) include young, aged, homeless, indigenous groups, disabled and those individuals who have compromised health. In Queensland, Indigenous peoples and their communities have been found to be vulnerable to Japanese Encephalitis (JE) because of lower standards of living and existing health problems than non-indigenous groups (Green & Preston 2006). A lack of basic infrastructure in remote indigenous communities contributes to a poor adaptive capacity and even greater vulnerability. Young children have been found to be sensitive to Japanese Encephalitis (JE) because of higher metabolic and an immature immune system. Pre-existing Japanese Encephalitis (JE) disease or illnesses and medication can increase vulnerability to a range of potential health impacts (Ellemor 2005). c) Economical Vulnerability Japanese Encephalitis (JE) vulnerability depends on the level of institutions and economic developments (Allen Consulting Group 2005). Economic vulnerability is more in Queensland where institutional and economic circumstances are less favorable. Also, it has been noted vulnerability is highest where there is “the greatest sensitivity to climate change and the least adaptability” (Watson, Zinyoera & Moss 1996). Many indigenous people live in remote areas of Australia, majority of them live in settlements in north of Australia. Most of communities found in these settlements have inadequate healthcare services and frequently have dilapidated housing that attract host vectors, a lack of meaningful employment opportunities and insufficient or inappropriate health services (AIHW 2006). The shortage of nurses and doctors for these communities provides a level of stress on the public health system that has been compounded with the impacts of Japanese Encephalitis (JE) caused by climate change. The problem of Japanese Encephalitis (JE) has been further been exacerbated by high population growth rates of indigenous population (Ellemor 2005). An increase in the number of indigenous people living on coastal and in floodplains areas has proportionately increase the number of people exposed to Japanese Encephalitis (JE) disease (Patz & Olson 2006). Health early warning systems A fundamental requisite for Japanese Encephalitis (JE) adaptation is to improve surveillance and monitoring of the disease and mortality in sensitive regions (Allen Consulting Group 2005). In Queensland as compare to the rest of the country, Japanese Encephalitis (JE) disease surveillance systems are poorly and inconsistent managed (Hennessy, Pittock, Walsh, Suppiah, McInnes & Bathols, 2004). The challenge to the authorities in Queensland is to empower communities particularly indigenous as well as incorporate strong public health infrastructures in those regions so as to achieve effective disease surveillance. Health early warning systems are important in the context of Japanese Encephalitis (JE) disease, extreme weather events that spread the disease, and the pattern of outbreaks of the disease. The effectiveness of health early warning systems will largely depend on the current and past disease surveillance and monitoring, and accurate and reliable climatic forecasts (McMichael, Woodruff and Hales 2006). Health early warning systems are a win-win strategy that has been widely adapted in other regions such as Japan as a strategy that reduces the risk of Japanese Encephalitis (JE) disease whilst increasing adaptive capacity that is most essential in the context of Queensland region. The findings of recent reports have highlighted the urgent need for improved technologies and surveillance systems, especially for Japanese Encephalitis (JE) in Queensland region and for increased cooperation between authorities that are responsible in the identification and public health response to disease and outbreaks (AIHW 2006). Diagnosis For a person suffering from Japanese Encephalitis (JE) diagnosis is made primarily on the basis of the patient’s symptoms and the knowledge of the kinds of sickness to a particular geographic location (Endy and Nisalak 2002). Most techniques used to diagnose Japanese encephalitis don’t yield quick results. In most cases Immunofluorescence tests is used to verify the disease; mostly used where special viral markers will react with antibodies in the body that have been tagged with a fluorescent chemical (Arai, Matsunaga and Takasaki T, et al 2004). Japanese encephalitis (JE) test results take time until week two but other tests can be used in comparing the presence and quantity of particular antibodies in the spinal fluid or human blood within week one with those present in the week tow of the sickness (Halstead and Jacobson 2008). Vaccination The estimated incidence of persons contracting Japanese encephalitis disease among travelers to Asia from non-endemic countries is less than one case per one million travelers (McMichael, Woodruff and Hales 2006). But the risk increases for travelers or expatriates who have longer duration of stay or whose plans include extensive outdoor activities in remote places (Currie and Jacups 2003). Since early 70’s only 56 cases of Japanese encephalitis among visitors or travelers from non-endemic countries have been recorded in the literature; since a Japanese encephalitis vaccine was licensed, only 5 per cent cases of Japanese encephalitis infection have been reported among travelers in Australia (Vaughn and Hoke 2000). Most of Japanese encephalitis cases are non-specific febrile or asymptomatic illness. Less than one per cent of Japanese encephalitis infections results in symptomatic neuroinvasive disease. However, when Japanese encephalitis disease does occur in a person, it usually very severe with a high case of fatality rate. For people travelling to areas that are rampant with Japanese encephalitis disease, vaccine that contains inactivated Japanese encephalitis virus can be used (Vaughn and Hoke 2000). The vaccine works by stimulating the immune response of a person to the Japanese encephalitis virus, without causing the disease. When the human body is exposed to viruses and bacteria, the immune system will produce antibodies against these foreign organisms. Ixiaro vaccine is widely used to prevent Japanese encephalitis. Ixiaro is a vaccine that contain in activated form of viruses or extracts that cause the Japanese encephalitis disease (Endy and Nisalak 2002). The vaccine will stimulate the body immune system to produce antibodies against the Japanese encephalitis virus and is given to prevent this disease in people travelling to areas where the virus is a high risk (Halstead and Jacobson 2008). Treatment There are no specific treatments that can be used to treat Japanese encephalitis. Antibiotics that are used are not effective against virus that causes the disease (Halstead and Jacobson 2008). Treatment of Japanese encephalitis usually targeted at symptomatic relief of the patient. In addition, treatment will also depend on the complications that are involved. Doctors will give a patient found to be suffering from Japanese encephalitis intravenous fluids that will help the patient maintain the hydration status. The doctor can then subscribe painkillers to reduce the associated pain. Also, Anticonvulsants to control seizures, ventilation support, and feeding are the standard treatments. In extreme cases surgical intervention may be used (Pittock 2003). Prevention The most important prevention method for people visiting endemic region is avoidance of vector mosquito that transmits the virus, particularly at night (Arai, Matsunaga, Takasaki et al. 2008) This can be achieved through the use of bed nets when a person is sleeping, also the use of mosquitoes repellent with diethyltoluamide (DEET) when the risk of contact with vector mosquitoes is high (Ellemor 2005). Other interventions that can be use to control vector mosquitoes is via use of larva-killing agents and insecticides, which have not proved efficacious (Halstead and Jacobson 2008). Conclusion The health status of people living in remote areas is likely to be adversely affected by the effects of climate change in a number of indirect and direct ways. This has reflected on the vulnerability of indigenous communities to reduced adaptive capacity and environmental change. This situation has created a challenge to the local governments or state to provide adequate levels of advance management, planning and care to reduce climate-related risks. Those factors that make management, prevention and treatment of Japanese encephalitis disease to be complex include the lack of public health infrastructure appropriate to the likely scale of the problem. There is need for more funding from the government for primary health care programs that will be used to prevent and treat Japanese encephalitis disease, more preventative facilities to lower existing burden of disease, more doctors and nurses in communities with cross-cultural awareness, improvement of infrastructure in outstations and communities, and greater education about how to reduce Japanese encephalitis disease and the provision of resources to implement appropriate activities to do so. References AIHW (2006) Australia's Health 2006. (Australian Institute of Health and Welfare, Canberra). Allen Consulting Group (2005) Climate Change Risk and Vulnerability: Promoting an efficient adaptation response in Australia. (Australian Greenhouse Office, Canberra). Arai S, Matsunaga Y, Takasaki T, et al. (2008). Japanese encephalitis: surveillance and elimination effort in Japan from 1982 to 2004. Jpn J Infect Dis; 61:333. Blaikie, P., Cannon, T., Davis, I. and Wisner, B. (1994). At Risk: Natural Hazards, People’s Vulnerability, and Disasters. London: Routledge. Currie, B. and Jacups, S. (2003) 'Intensity of Rainfall and Severity of Melioidosis, Australia'. Emerging Infectious Diseases 9, 1538-1542. ECU (2006) Australian Indigenous HealthInfoNet, Edith Cowan University http://www.healthinfonet.ecu.edu.au/ Ellemor, H. (2005) 'Reconsidering emergency management and Indigenous communities in Australia'. Environmental Hazards 6, 1-7. Green, D. (2006) How Might Climate Change Affect Island Culture in the in the Torres Strait? CSIRO research paper 011 (CSIRO, Aspendale). Green D, and Preston B (2006) Climate Change Impacts on Remote Indigenous Communities in Northern Australia. www.dar.csiro.au/sharingknowledge/regions.html Halstead, S, Jacobson, J. (2008). Japanese encephalitis vaccines. In: Vaccines, 5th ed, Plotkin, S, Orenstein, W, Offit, P (eds), Saunders Elsevier. Hennessy, K., Pittock, A., Walsh, K., Suppiah, R., McInnes, K. and Bathols, J. (2004) Climate change in the Northern Territory: consultancy report for the Northern Territory Department of Infrastructure, Planning and Environment. (CSIRO, Aspendale) Ellemor, H. (2005) 'Reconsidering emergency management and Indigenous communities in Australia'. Environmental Hazards 6, 1-7. Endy TP, Nisalak A. (2002). Japanese encephalitis virus: ecology and epidemiology. Curr Top Microbiol Immunol; 267:11. Jackson, S. (2005) 'A burgeoning role for Aboriginal knowledge'. ECOS June-July 2005. IGWG (2004) Environmental Health Needs of Indigenous Communities in Western Australia. The 2004 survey and its findings.www.dia.wa.gov.au/EHNCC/EHNS2004/EHNSReport2004.pdf McMichael, A., Woodruff, R. and Hales, S. (2006) 'Climate change and human health: present and future risks'. The Lancet Mar 11; 367(9513):859-69. Patz, J. and Olson, S. (2006) 'Malaria risk and temperature: Influences from global climate change and local land use practices'. Proceedings of the National Academy of Sciences 103, 5635-5636. Pittock, B. (2003) Climate Change: An Australian Guide to the Science and Potential Impacts. (Australian Greenhouse Office, Canberra, Australia). Smith, B. (2004) 'Some Natural Resource Management Issues for Indigenous People in Northern Australia'. Paper pres. Arafura Timor Research Facility Forum, ANU. Vaughn DW, Hoke CH Jr. The epidemiology of Japanese encephalitis: prospects for prevention. Epidemiol Rev 2000; 14:197. Watson, R.T., Zinyoera, M.C., and Moss, R.H. 1996. Climate Change. ( 1995). Impacts, Adaptations and Mitigation of Climate Change: Scientific-Technical Analysis. Contribution of Working Group II to the Second Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge: Cambridge University Press. Read More