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Here is a term paper on ‘Climate Change and Human Health’ for class 9, 10, 11 and 12. Find paragraphs, long and short term papers on ‘Climate Change and Human Health’ especially written for school and college students.
Climate Change and Human Health
Term Paper Contents:
- Term Paper on the Introduction to Climate Change and Human Health
- Term Paper on Vectors and Vector Borne Diseases
- Term Paper on the Reemergence of Diseases
- Term Paper on Waterborne Infectious Diseases
- Term Paper on the Remarks on Climate Change and Human Health
Term Paper # 1. Introduction to Climate Change and Human Health:
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In 2003, heat waves killed 35,000 people in Europe out of which 14,300 where from France only. Majority of them were geriatric population more than 75 years of age. The nature of illness was heat exhaustion or heat stroke, cardiovascular and kidney diseases. City dwellers are at particular risk because of elevated temperature in cities known as urban heat island effect.
Global warming is acknowledged by the scientists around the world to be a reality and to have been caused primarily by the human activities associated with civilization. As the earth warms, the delicate balance of climate, weather events of climate and life is disrupted. Consequences threaten human health and, ultimately, survival. WHO reports that long-term climate changes profoundly affect the pillars of public health including water, sanitation, air quality, food and level of allergens?
Human life is dependent on the dynamics of the earth’s climate system. The interactions of the atmosphere, oceans, terrestrial and marine biospheres, cryospheres and land surfaces determine the earth’s surface climate. The temporal and spatial changes in temperature and moisture are likely to change the ecology and biology of vectors as well as intermediate hosts (human beings, animals), which aggravates the incidences of disease transmission.
Such reemergence of diseases are categorized as vector borne parasitic diseases (malaria, leishmaniasis, kala-azar, Chaga’s disease, filaria, etc.), viral diseases (dengue fever, yellow fever, West Nile fever, Rift Valley fever, tick borne encephalitis, etc.) and bacterial rickettsial diseases like Lyme borreliosis, tularemia and plague.
India is afflicted with six major vector borne diseases namely malaria, kala-azar, dengue, chikungunya, filariasis and Japanese encephalitis. Malaria ranks number one and has the largest disease burden (illnesses, deaths, financial costs and other indicators) of any vector-borne diseases worldwide.
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Term Paper # 2. Vectors and Vector Borne Diseases:
Some 350-500 million people of the world are suffering from malaria, resulting in the deaths of one to three million people. If global temperature increases by 2-3°C, as expected, it is estimated that the population at risk for malaria will increase by 3- 5 per cent, which means that millions of additional people would probably become infected with malaria each year. It is estimated that annually there are over 100 million cases of dengue infection worldwide.
The case-fatality rate of its more serious form, dengue haemorrhagic fever (DHF), is about 5 per cent, mostly among children and young adults (CDC, 2010). As per National Vector Borne Disease Control Programme (NVBDCP), in 2007, cases and deaths due to Japanese encephalitis, dengue and visceral leishmaniasis were 4022 (963), 5534 (69) and 44001 (189) respectively. In India, around 60,000 suspected cases of chikungunya were also reported in 2007. In addition to mortality, vector borne diseases cause morbidity of millions of persons resulting in loss of man-days causing economic loss.
Climate change has the potential to alter the average exposure of human populations to vectors by changing the geographical distribution of conditions that are suitable for the vectors and disease pathogens. An increase in global temperatures will result in an expansion of warm temperature regimens into higher altitudes and latitudes. Any associated changes like rainfall in tropical and subtropical zones will also render habitats more or less suitable for vectors.
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Climate change will affect both the invertebrate vectors and the development of pathogens in those vectors. Basic biological considerations indicate that with global warming, the duration of the growth season will increase, allowing more generations of vectors each year in cooler areas. Mosquitoes and other vectors are highly sensitive to the changes of temperature.
The higher temperature causes:
i. Boosting of reproductive rates, lengthening of the breeding seasons and increased susceptibility to bites.
ii. Shortening of the time to mature the pathogens to an infectious state.
iii. Expanding the mosquitoes’ range to higher elevations and more northern latitudes, potentially putting previously unexposed population at risk.
Ticks maintain multiple and diverse disease agents (including bacteria, viruses, and parasites) and serve as bridging vectors between animal reservoirs of the disease and humans. Changing weather patterns associated with climate change have induced shifts in the distribution of vector ticks carrying Lyme disease. Modelling indicates that in the future, the tick that carries Lyme disease will expand to Canada.
Fleas are best known as vectors of the causative agent of plague. Plague has caused millions of human deaths, especially during the black death of the middle ages. Plague still exists, notably in New Mexico, where its prevalence seems to correlate with the timing and amount of precipitation.
Recently, studies of plague transmission in the United States found that the pattern of human plague cases has shifted northward as temperatures have warmed. It is predicted that some northward expansion of the disease could occur from New Mexico into Wyoming and Idaho.
Term Paper # 3. Reemergence of Diseases:
Reemergence of diseases refers to disease outbreaks, which are previously controlled with ease by chemotherapy but now developed resistance and reappearing in the form of epidemics. Changes in the local ecological patterns not only increase vector densities but also facilitates the reintroduction of newer pathogens.
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Such changes in the habitats are further compounded with breakdown of the vector control measures. Alterations in the hydrological cycles (rainfall-evaporation cycle), melting of glaciers and failure in ‘flushing mechanisms’ of warm sea water from Gulf region to the Atlantic ocean are the added attributes.
The ecology and epidemiology of vector borne diseases can be better described by the concepts of disease triangle of host-pathogen-environment (Figure 20.1). This problems are further complicated with recently documented reports of pesticides menace.
The later includes physiological resistance, decrease in agricultural growth (especially rice), alteration in ‘bird life cycle’ and pyrethroids induced health hazards like hormonal changes and carcinomatous conditions due to reduced cholinesterase levels in the exposed population.
Successful control over the vector borne diseases could be summarized under following heads:
i. Effective surveillance to provide feedbacks assuming that the benchmarks have been established.
ii. Viable public health infrastructure to deliver the services,
iii. Detection of actual cases and their reporting to the competent authority,
iv. Community ownership of the newly developed control measures,
v. Climate forecasting and early warning system by developing suitable outbreak indicators,
vi. Research and development in the field of malaria genome project and developing newer antimalarial molecules or recombinant vaccines,
vii. Use of biopesticides (entomopathogens) like Gambusia affinis (mosquito fish) or Mesocyclops asperiornis (copepod).
Term Paper # 4. Waterborne Infectious Diseases:
Like vector borne diseases, waterborne infectious diseases are also strongly affected by changing climate. During drought, water scarcity results in poor sanitation and much of the population can be exposed to potentially contaminated water. For example, there is currently an epidemic of cholera in northern Kenya during severe drought.
Like drought, excess rainfall and flooding can also contribute to epidemics of waterborne infectious diseases, because of poor sanitation resulting from run-off from overflowing sewage lines or the contamination of water by livestock. An example is the 1993 epidemic of diarrhoeal disease due to Cryptosporidium in Milwakee after heavy spring rains.
Global warming also rises water borne infectious diseases due to change in water cycle. Infectious diarrhoea is caused by bacteria, virus and parasite due to contamination from food and drinking water. It is predicted that by2030, there will be 10 per cent more diarrhoeal disease and is expected to be increased due to climate change and that will primarily affect the health of young children. Indeed, the impact on children might well be amplified by the effects of such diseases on malnutrition, development and cognition.
Cholera outbreaks usually occur from bacterial contamination from river, estuaries and coastal water. Scientists could observe that there exists a strong correlation between increase in sea surface temperature and onset of cholera epidemic. Vibrio cholera is a natural inhabitant of the coastal, estuarine and riverine areas of tropical and temperate regions. The micro-organism is known to have been traveled by land, water and air via international trade and migration of population.
It has been observed that warm water along the coast, coupled with plankton blooms fostered by El Nino rains helped to multiply the cholera bacteria in the ocean. Sea surface temperature and plankton blooms could be considered as effective indicators in predictive markers of cholera outbreak. Higher water levels carry infected water further inland in one hand and reduction in salinity (due to influx of water) on the other, which worsen the situation.
In this regard the declaration of Rita Colwel, the Director of the National Science Foundation (USA) may be quoted:
“We can learn from the oceans as a vector of life and death, health and disease; a purveyor of environmental process; and a model of environmental and human health”.
Term Paper # 5. Remarks on Climate Change and Human Health:
Global change drivers are identified to have been left severe impacts on human health. These drivers are intensification of agriculture, variation of vegetation density, trade and travel, industrialization and population migration (Figure 20.2).
Climate change is a new problem in the field of human health but little research effort has so far been directed to measure the effects of long-term climate change on vector borne and other reemerging diseases. Many of the principles and problems (variability in monitoring and surveillance, necessity for long data sets to overcome statistical noise cofounding variables, publication bias, etc.) applied to detect the changes in human diseases.
However, there are significant additional challenges mainly involved with differentiating climate influences from the other multiple determinants of vector borne disease transmission. Therefore, field based epidemiological research on climate influences on disease causation requires even greater emphasis on differentiation between the effects of coexistent climate and non- climate factors. Many environmental and socioeconomic factors have affected the distribution and seasonality of vector borne diseases in recent years.
The need of the hour is to develop holistic approach to risk assessment (outbreak indicators) of vector borne diseases under climate changes. Appropriate tools for the management response must be developed on the basis of adaptation technologies, cultural parameters, public health infrastructure and resources. Newer statistical models are to be innovated to forecast the resurgence of diseases in terms of meteorological data, local ecological indicators including vector density, immunological status of human hosts.
To combat the consequences of climate change, we need to act in time by developing tools for early warning for seasonal forecasts, plan public health infrastructures, allocate resources and strengthen surveillance programs. Adaptation strategies must be considered to reduce disease burden, injuries, disabilities and death. It is concluded that culturally, economically, socially and environmentally sustainable programs may improve human health and personal development. Situation may also demand appropriate legislation in this regard.