The United Nations Framework Convention on Climate Change - Literature review Example

Transmission of the Dengue virus is mostly influenced by climate change among other factors. According to Intergovernmental Panel on Climate Change (IPCC), climate change refers to the change of state of the climate that can be identified by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer. These changes that occur over a period of time can be attributed to human activities or natural variability. However, the United Nations Framework Convention on Climate Change defines climate change as that change which can be attributed directly or indirectly to human activity that significantly changes the composition of the global atmosphere. This is in addition to natural climate variability observed over comparable time periods (IPCC, 2007). Climate change is expected to bring about more severe and long-lasting outbreaks of vector-borne diseases, and greatly influence modes of transmission across countries (Dunstan et al, 2008). These expected changes are likely to affect the movement of blood products all over the world. In recent times, the outbreak of dengue fever resulted into a long and unexpected shortage of fresh blood products. In the coming years in Australia, the areas that favor transmission of dengue fever are predicted to spread out to several states and include new populations if effective measures are not put in place to control climate change. In this paper the role that climate change plays in the transmission of dengue fever is investigated. It is hypothesized that climate change is likely to affect supply of blood by altering the movement of vector-borne disease. The following fifteen literature reviews try to demonstrate and support this assumption (Gibbons & Vaughn, 2002) According to Beebe et all (2009.) most of the observed average warming over the last 50 years have been due to increase in greenhouse gases and it is likely that there is a considerable human induced warming. In recent years, the Australian public has been increasingly concerned about the impact of pollution on its air and water. This concern has led to research and speculation about the ability to control the harmful effects of certain technologies on the natural environment. The IPCC (2007)report described the described the fundamental problem in terms of a clash between the speed of change in human civilization and the environment; has also noted that most vital natural resources are rapidly being exhausted. The report further claimed that human civilization had been changing and becoming more complex at an accelerating rate, the ideas, facts and procedures that make up science and technology at any given time serve as a platform for future progress. However, the report explicitly stated some of the limitations in measuring global climatic changes. For example, it noted that climate changes are not easy to determine or detect due to adaptation and non-climatic drivers. In addition, there is a problem of analyzing and monitoring changes taking place in extreme events such as drought as well as the frequency and intensity of precipitation. The IPCC report found that greenhouse gases emission, at the current time would increase the level of warming and bring about many changes during the 21st century. These changes were estimated to be more severe than those of the 20th century. Indeed the report provided a raft of measures that were seen as important in stabilizing levels of GHG concentrations that had been observed. Stabilization according to the IPCC report would be achieved by deploying a portfolio of technologies. And those expected to be commercialized in coming years. Natural cycles of purification can absorb only a limited amount of certain artificial substances before ecological damage is done. Water pollution occurs when streams, rivers, lakes, and oceans can no longer purify themselves. When the wind, rain, and snow can no longer remove the particles deposited in the air by machines of various kinds, pollution is the result (IPCC, 2007) Sometimes technologies that seem benign and that are taken for granted as part of everyday life unanticipated consequences (Liumbruno et al, 2008). Earlier in this century pesticides and herbicides revolutionized agriculture, making it much more productive. Subsequent research has linked many of theses chemicals to the destruction of fish and birds and to certain cancers in humans. Along the same lines, for many years humans used aerosol containers for purposes ranging from personal hygiene to applying whipped cream to ice-cream sundaes. In the mid 1970s the suspicion that a propellant used in aerosol cans was eroding the atmospheric ozone layer, which protects humans from harmful radiation, led to the use of different propellants. In many cases the technology exists to control environmental damage, but powerful interests do not wish to shoulder the cost of doing so (Wu et al, 2009). Here the problem becomes one of creating a political consensus around a solution. Reiter (2008) explains that the technology needed to get out of jams that earlier inventions have helped put humans into does not yet exist. Therefore, advanced economies around the world are consuming energy in the form of oil, which is becoming depleted and for which an adequate substitute has not been found. Any technological solution to this and other problems will almost inevitably contribute top a whole new generation of crises. In addition, further research would be needed to improve the technological performance, reduce costs and achieve social acceptability of new technologies. What is clear from the study by Wu et al, (2009) is that climate change is on and increasing and if immediate measures are not put in place, then the observed changes in the climate would continue to affect the health of people. In addition, technological breakthroughs are also a recipe of other problem. The global changes in climate that are being observed currently are predicted to have adverse effects on the health of people (Reiter, 2008). In Australia, these effects comprises of increased occurrences of vector-borne diseases as well as the geographical areas affected (Wu et al, 2009). Other areas of concern include the number of people affected, number of deaths as well as hospitalizations from exposure to heat in addition to incidences of bacterial infections such as gastroenteritis. In a journal article by Randolph et al. (2007) the authors argued that if no concrete actions were to be taken to mitigate the effects of climate change by lowering carbon emissions, then the distribution of dengue-transmission would advance southward along the Queensland coast and also encompass the northern parts of Western Australia. The authors hypothesized that transmission areas were likely to increase to areas like New South Wales along the east coast all the way to Port Hedland in Western Australia if conditions were wetter. In addition, transmission was expected to occur throughout the Northern Territory. According to the article, if a several outbreaks of dengue were to take place concurrently in several areas, the supply of blood would be greatly reduced in Australia. The authors identified that people who were living in town and cities and who were not exposed to dengue fever before would suffer most during an outbreak. In a research article by Kuno (1995), it was found that dengue fever was on the rise worldwide and that it was a common health problem in Australia. Recent studies have also shown that dengue fever has continued to be one of the leading health problems in Queensland in northern Australia. It has been found that the disease is associated with serious health complications such as the reduction of the availability of fresh blood products leading to serious illness. Therefore dangue fever is a potentially dangerous disease transmitted by Aedes aegypti mosquito (Kuno, 1995). The dengue viruses are transmitted between humans through a bite from Aedes aegypti (Wu et al, 2009). When dengue virus enters the human body through the bloodstream it spreads throughout the human body. In the human body, dengue infections causes fever, general body aches, headache and occasionally may result into minor bleeding. According to Kuno (1995) the occurrence of dengue fever may progress into a life threatening complication known as dengue hemorrhagic fever. This happens after a subsequent infection with another dengue serotype (Reiter, 2008). Australia is potentially vulnerable to increased occurrence of dengue fever; however, the virus is not yet endemic in the country (Bulto et al, 2006).There has been a sporadic outbreak of dengue fever in northern Queensland. Several incidences of dengue have been reported in international travelers who return in dengue endemic countries then transmit the viral infection to other people. According to literature study on blood transfusion and dengue, there are no reports of blood transfusion-associated dengue in endemic countries; however, there have been reports of possible transmission of dengue in health care setting in Hong Kong and Singapore (Kuno, 1995). Wilder-Smith & Schwartz (2005) observe that the level of viremia required to cause clinical dengue fever cases in unknown. However, the potential risk to blood supplies is high in endemic countries. A study which included the collection of blood specimen across Australia by the Australian Red Cross Blood Service (ARCBS) indicated that an estimated 26,000 blood donations from remunerated volunteer donors are required weekly or more than 1.35 per year represents 0.06 units for each person yearly for a population of 22 million to be used for screening test (Bulto et al, 2006). Currently, there is no screening test available for the dengue virus, specimen obtained from platelets and red cells in a dengue pandemic area or from travelers are not used for screening even if they are obtained from asymptomatic patients since, they may carry the virus unknowingly (Wilder-Smith & Schwartz, 2005). Plasma collected from dengue fever prone areas have been used to manufacture blood products after being passed through a process known as fractionation. From 1992 to 2006, there were over 3,000 confirmed cases of dengue fever in Australia. On average, there are approximately 200 cases annually and additional subclinical cases associated with minor symptoms. There were five death cases attributed to dengue fever during the period. The spread of dengue fever in non endemic regions such as northern Queensland are sporadic with variation in the number cases occurring yearly. In the same period, the occurrences of dengue outbreaks became more regular with major and minor outbreaks being recorded. The major causes were attributed to international travel in Australia, particularly, in the northern part of Queensland (Wilder-Smith & Schwartz, 2005). Public health authorities in northern state of Australia have embarked on measures to curb the outbreak of dengue through public education to campaign for the eradication of mosquitoes and their breeding sites. Recently, more than 900 cases recorded from the outbreak that made the ARCBS to require extra donations from various parts of Queensland to ensure sufficient provision of blood supply for screening tests. In addition, health officials have prohibited the use of fresh blood from dengue pandemic areas until no new incidences are reported (Bulto et al, 2006). Climate change is a factor that has led to the spread of dengue fever, the vector borne disease has shown a clear related pattern because rainfall and temperature leads to the spread of mosquito vectors with the likelihood that they will transmit the dengue virus from one person to another. The use of global climate models indicates that increases in temperature have implications to the increases to the latitudinal range of the spread and transmission intensity in dengue pandemic areas. Thus, climate change is one of the factors that have led to the proliferation of the dengue virus in marginal areas. Studies have revealed that, temperature affects insect survival time, habitats, maturation and infective periods of the Aedes Aegypti. Gubler DJ. (2007) used a predictive model to come up with an estimate changes to dengue transmission. The model used predicted global dengue presence with an accuracy of 90 % in those areas which were thought to have more than 50% chances of transmission. This meant that some areas that returned a lower than 50% probabilities were still considered for dengue transmission. The problem with this model is that it does not predict vector distribution but rather regions that are suited for future transmission. It is therefore a subjected method and is guided by urban features as well as infrastructure. For example, the author determined that near universal water reticulation in non-remote areas of Australia had reduced domestic storage and therefore, A .aegypti breeding sites as well. These behaviors and infrastructures are subject to change. However, Gibbons & Vaughn (2002) have shown that human adaptation to climate change could lead to further spreading of the Aedes mosquito in Australia and other epidemics. Although the authors, however, did not include transmission intensity, it is a likely outcome of climate change. Health professionals in Australia estimated the costs from 2006 to 2008, but never accounted for any changes in costs over time in the primary care intervention (Liumbruno et al, 2008). The assumption made was that, the projected costs to curb the spread would remain the same over time and the epidemiology of dengue fever would not change. Thus, the transmission patterns of dengue would become an established epidemic in Australia leading to an increase in the costs of health related systems above estimated values for each person. The prevailing scenario would lead to periods with few or no cases of dengue fever. Hence, there is need to embark on a massive campaign to eradicate mosquitoes and their habitats, especially in urban centers. The eradication program requires trained personnel to participate in a broad scale and intensive community education and awareness and the destruction of the breeding sites in selected hot spots and local areas in the urban centers where the outbreak of dengue has been an outbreak of dengue virus. However, there have been no assumptions made concerning international travelers and future tourism patterns which may have implications to the spread of dengue virus. Currently, dengue outbreaks in Australia follow a cycle starting with an infected traveller from a dengue endemic country and enter into the country. This has contributed to cases of dengue infections and the introduction dengue hemorrhagic disease (Liumbruno et al, 2008). Severity and symptoms of dengue fever vary from person to person. Factors that cause the spread and severity of the disease include ethnic background, age, sex, nutritional status, genotype of the infecting virus, and the efficiency of the health care system. Hence, it is important to consider the future of Australia’s health system, demography, social, and environmental factors that may lower the severity of the disease to match the current trend. The study by Gould & Higgs (2009) shows that there are few cases of dengue fever related deaths in Australia, with figures indicating few deaths each year. However, the number of deaths associated to exposure to dengue serotypes is projected to increase if the transmission of dengue virus becomes more prevalent and the virus become endemic as the risk of getting recurrent infections increases (Gould & Higgs, 2009). In future, it is assumed that cases of dengue and dengue hemorrhagic fever will be likely to increase. The disease is very common among children because older patients especially in the northern part of Queensland have a long period for dengue serotypes, meaning that the older people or those previously infected, for example international travelers, are very susceptible to the disease. The occurrence of dengue serotypes may frequently occur in the coming years due to increased virus activity, random chance, and increased tourism activities across the globe. Global climate change could increase the likelihood of the outbreak of the viral infection, for instance, it is predicted that there is likelihood in the spread of dengue fever in various parts of the world such as South America, Australia and Africa. Low risk areas, particularly, India, the Middle East, and South East Asia may become potential high risk areas for dengue infections due to climate change. The global climatic models illustrates that there is the possibility of an increase in the transmission intensity in various geographic locations such as the northern states of Australia, India, Thailand, eastern and the horn of Africa, as well as, South and central America (Gould & Higgs, 2009). The use of empirical models has led to the prediction that the potential of dengue virus is likely to increase in major urban areas even with a slight increase in temperature (Gould & Higgs, 2009). In Australia, the use of climate models suggest that the supply of blood and dengue are climatic problems, hence, there is a correlation between dengue fever and climatic variables. Climate change has been recorded in various parts of the world with incidences of dengue fever predicted to increase in many countries. The likelihood for the changes in climate to affect future supply of blood widens scope to other vector-borne pathogens. The transmission of other vector-borne viruses in Australia is not known at the moment. Randolph et al. (2007) posits that viruses such as Ross River virus and Murray Valley Encephalitis are expected to continue to increase in intensity as well as spread more geographically as conditions for mosquito replication become more conducive. This is expected to impact negatively on Australia’s blood supply. Climate change effects have also been determined to contribute to future shortages across the world as other global vector-borne diseases become affected. According to a modeling by Reiter (2008), it was determined that there is considerable evidence that transmission of vector-borne diseases was expanding geographically. According to Reiter, P. (2007) the emergence of Chikungunya in Italy led to the reduction of blood supply and manufacture of plasma. Indeed movement of blood and its products also affects the safety of blood. The risk of transmission is not contained in an affected area and is likely to lead to local transmission in an area that was not affected previously. Climate change in Australia, just like in other parts of the world will be affected by carbon emissions (Jury, 2008).The level of emissions on the other hand depend on the actions of the governments concerned, and more so, those that are currently polluting the environment more. While climate mitigation efforts are still being pursued, strong reductions in emissions are required so as to the average rate of global warming. It has been observed that a 50% reduction in emission by 2040 is needed to stabilize carbon dioxide concentration below 450ppm and warming below 2C (Wu et al, 2009). From this discussion, it is clear that climate change is causing much harm to people and there international actions to reduce carbon dioxide are needed. The above literatures seem to support the hypothesis that climate change is likely to affect supply of blood by altering the movement of vector-borne disease. However, the virus that transmits dengue fever as well as the vector are very sensitive to climate and, therefore, even a small increase in average world temperatures will most likely affect transmission of the vector-borne disease. As shown by recent outbreaks of dengue disease, it is impossible to control the disease as climate changes. On the other hand, it is not easy to access the impacts of climate change on any health outcomes so as to determine likely changes in distribution. These studies show how climate changes can affect the supply of blood in Australia by extending the areas that favor dengue virus and also they illustrate the need for a global concern as well as the importance for future research to determine climate impacts on health. References Beebe N, Cooper R, Mottram P, Sweeney A. 2009. 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