Controlling Malaria as a Significantly Intricate Disease - Assignment Example

Controlling Malaria: A Critical Evaluation of the Malaria Vaccine When speaking of diseases, Malaria is a significantly intricate and complicated one. The history and both past and present seriousness of it must be understood, and in order to come to a clearer and more knowledgeable viewpoint, the following questions must be addressed: 1. What is malaria 2. What has been used in the past to control malaria 3. What is used now to control malaria 4. How does this treatment work physiologically 5. How is this vaccine in comparison to the previous methods of control 6. What effect is this having and what effect will it have on controlling malaria in the future By thoroughly discussing these six questions, we can gain a more intellectual and definitive objective on this subject matter. This is what will be dissertated in the following. What is Malaria Malaria is literally defined as "An infectious disease characterized by cycles of chills, fever, and sweating, caused by a protozoan of the genus Plasmodium in red blood cells, which is transmitted to humans by the bite of an infected female anopheles mosquito." ("Dictionary", 2006). Plasmodium has four different species of one-celled parasites, and malaria can be caused by any one of these. Although four species of malaria parasites can infect humans and cause illness, only malaria caused by Plasmodium falciparum is potentially life-threatening. It is this form of malaria which is responsible for "80% of cases and 90% of deaths." ("Wikipedia", 2006). It is children under the age of five and pregnant women who are the most vulnerable to the severe forms of malaria. Once a person is bitten by the female anopheles mosquito, young forms of the malaria parasite are then injected into the person's blood. The parasites then travel through the person's bloodstream and into the liver, where they continue to grow to their next stage of development. Approximately a week later, the parasites will leave the liver and reenter the bloodstream. They then invade the red blood cells, finish growing, and begin to multiply quickly. "The number of parasites increases until the red blood cells burst, releasing thousands of parasites into the person's bloodstream. The parasites attack other red blood cells, and the cycle of infection continues, causing the common signs and symptoms of malaria." ("DHPE", 2006). Persons who are infected with malaria will typically experience cycles of chills, fever, and sweating that usually recur every 1, 2, or 3 days. The serious attack of the malaria parasites on the person's red blood cells often makes the person's temperature rise and the person will therefore probably feel quite hot. Following this, the subsequent bursting of red blood cells makes the person feel cold and have hard, shaking chills. The most usual diagnosis of malaria involves a microscopic examination of blood films, because "each of the four major parasite species has distinguishing physical characteristics visible under a microscope." ("Wikipedia", 2006). Malaria is considered to be a worldwide problem, in that many countries have been experiencing a current sudden resurgence in cases caused by Plasmodium falciparum, and due to urban migration, poverty, and poor sanitation, malaria has now returned to the cities where it was once eliminated. However, the potential also exists for malaria to become re-established in places such as the United States. In fact, currently, about 1,200 malaria cases are reported each year in the United States. There is as of present no vaccine against malaria. What has Been Used in the Past to Control Malaria The goal of controlling malaria is to reduce as much as possible the health impact of malaria on a population, by means of using the resources available, while also taking into account other health priorities. Although controlling malaria certainly does not eliminate the disease totally, complete elimination of the malaria parasite would constitute eradication. "While eradication is more desirable, it is not currently a realistic goal for most of the countries where malaria is endemic." ("CDC", 2006). During the 1890s and 1990s, the burden of malaria increased in many areas, especially in third-world countries were it was already most imminent, and the reasons for this increase were resistance to the antimalarial drugs which were used quite commonly in that era. The first recorded treatment of malaria actually dates back to 1600, when "the bitter bark of the Cinchona tree in Peru was used by the native Peruvian Indians." ("Nobel", 2006). It was in 1889 that the protozoal (single celled parasite) cause of malaria was discovered by Alphonse Laveran, who was working in Algeria at the time, and who then went on to begin his research on the disease at the military hospital of Bone in Algeria. Through his research and findings, Laveran was nonetheless successful, using his primitive method of examination, in distinguishing and describing most of the more important forms adopted by these new bodies, which varied greatly in their appearance. There was also the discovery of the insecticide DDT in 1942, which was founded by Paul Muller the Nobel Prize Laureate in Physiology or Medicine, 1948. "Subsequently, widespread systematic control measures such as spraying with DDT, coating marshes with paraffin (to kill Anopheles mosquito larvae), draining stagnant water, and the widespread use of nets and cheap, effective drugs such as chloroquine were implemented - with impressive results." ("Nobel", 2006). Chloroquine was a very effective drug for both treatment and prophylaxis of malaria. The first recording of use of chloroquine was in the 1940s shortly after the Second World War and was effective in curing all forms of malaria, with the positive conclusion of few side effects and low in cost. Alebrin (or Mepacrine) was a drug which was first developed in the early 1930s, and although at the time of the Second World War it was used as a prophylaxis on a large scale because it was then considered a safe drug, it is now considered to have too many undesirable side effects and is therefore no longer used. Mefloquine (or Larium) was first introduced in 1971, and "is related structurally to quinine." ("Nobel", 2006). Widespread resistance has also come around for this drug, which today also shows many undesirable side effects - two significant explanations for the decline in its use today. Halofantrin (or Halfan) is a drug which is not related to quinine, and was first introduced in the 1980s. Again, this is another drug which resulted in having bad side effects, as well as the gaining of resistance to the drug itself. Halofantrin has in fact been associated with neuropsychiatric disturbances, and "is contradicted during pregnancy and is not advised to women who are breastfeeding. Abdominal pain, diarrhea, puritus, and skin rash have also been reported." ("Nobel", 2006). Malarone is a drug which was released in the 1990s, and is in fact still used as a prophylactic in some countries. The drug combination has been found to be 95% effective in otherwise drug resistant falciparum malaria. Artemisinin was originally derived from a Chinese herbal remedy and covers a group of products. While they are highly used in Southeast Asia, they are not licensed much in the Western world. Although the spraying of DDT never truly eradicated the mosquitoes anywhere, it was certainly a great cause in the slow and progressive deterioration of the malaria situation, and was the most notorious method for controlling malaria in the past. What is Used now to Control Malaria Although some of the drugs from the past are continued to be used for the control of malaria, there are also new methods which have come about. There are effective anti-malaria drugs and the W.H.O. emphasizes early diagnosis and the prompt treatment of malaria. However, again alike the past, there are continued major problems of drug resistance, particularly to chloroquine which has been the mainstay of malaria treatment, especially in Africa, because of its low cost and relative freedom from side effects. DDT continues to be highly recommended in the control of malaria in today's world, mainly because of its cheapness per unit weight and its durability. Although DDT was banned from use in agriculture during the 1960s by the head of the EPA, William Ruckelshaus, the allowance of use on humans remains. This is due to the fact that countless studies have been conducted into the potential impacts of DDT on human health, yet none of them have been able to find any concrete evidence whatsoever of causing actual harm upon humans. "DDT is remarkably non-toxic to humans; people have tried to commit suicide by eating it and failed miserably." (Tren & Coticelli, 2005). How Does This Treatment Work Physiologically The way this vaccine works physiologically is that it is directed against the form of the malaria parasite that is injected by mosquitoes, which is known as the sporozoite. Afterwards, after immunization takes place, antibodies and white blood cells are produced which can then prevent the sporozoite from surviving or from further development in the liver. How is This Vaccine in Comparison to the Previous Methods of Control The vaccine which is still being developed was used to protect 2,022 children in Mozambique and actually cut the risk in half of developing severe malaria by 58%. Professor Pedro Alonso, lead researcher in the developmental aspects of the malaria vaccine, said that "We believe a malaria vaccine, even of moderate efficacy, could make a huge impactIt's difficult to imagine that we will have in the near future a magic bullet that by itself can sort out the problem of malariaJust like any other malaria control tool we have, like insecticide treated netsnone of them is 100% effective." ("BBC", 2006). The main difference between this vaccine and the methods used to control malaria in the past is just that - the past methods were used to control whereas this method is a vaccine. The difference in the statistical results is astounding, and what is planned to come in the future is even that much more remarkable. What Effect is This Having and What Effect Will it Have on Controlling Malaria in the Future In terms of the progressing vaccine for malaria, it will have a great impact on controlling malaria in the future. Regardless of the fact that it is not 100% effective, the results are sure to be astounding. This vaccine, although there are many others in development as well, has been shown to be the most promising yet. Allan Shapira, of Roll Back Malaria, said: "The research is very high quality and the findings are very encouraging." ("BBC", 2006). This vaccine brings hope, especially to third-world countries where malaria, even today, is basically an ongoing epidemic. As Mozambique's Minister of Health, Dr. Francisco Songane, says: "Malaria is the number one killer of African children. We did this not only for the people of Mozambique, but for the people all over Africa whose health and development suffer greatly from this terrible disease." ("BBC", 2006). References Akogbeto, M. 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Retrieved March 21, 2006, from http://www.mg.co.za/articlePage.aspxarticleid=256050&area=/insight/insight__africa/ "The Wellcome Trust". (2006). Malaria. Retrieved March 22, 2006, from http://www.wellcome.ac.uk/en/malaria/ "Wikipedia". (2006). DDT. Retrieved March 23, 2006, from http://en.wikipedia.org/wiki/DDT#Properties "WMR". (2006). World Malaria Report. Retrieved March 23, 2006, from http://www.rbm.who.int/wmr2005/html/exsummary_en.htm Yaro, A. S., Dao, A., Adamou, A., Crawford, J. E., Ribeiro, J. M. C., Gwadz, R., et al. The distribution of hatching time in Anopheles gambiae. Malaria Journal, 5:19. Read More