Filariasis
Filariasis or Lymphatic filariasis is considered as the forth most important cause of permanent disability around the world (WHO, 1998). Filariasis is also known by the name elephantiasis as it results in clinical symptoms such as swollen limbs and/or hardened, thickened skin. According to the WHO estimates there are a billion people at risk in approximately 80 countries. Over 120 million people already have been infected with Filariasis, and over 40 million are seriously debilitated and disfigured by the disease (Ottesen et al. pp. 491-503). This disease is a parasitic disease caused by thread-like worms or filariae and is commonly found in tropical areas. It is estimated that each adult worm survive for about six years in the human lymphatic system, and female worms release millions of microfilariae or the immature worms that circulate in the blood.
Though the infection is generally acquired early in childhood, however the symptoms of the chronic disease do not appear until adulthood. There are also cases where people with Lymphatic filariasis never develop clinical signs of their infections. However, studies show that such people actually have hidden, internal damage to the kidneys and lymphatic system. The damage to the lymphatic system generally causes fluid to collect and results in swelling in the arms, legs, breasts and genitals which is also called lymphoedema (Mortimer, pp. 1-20). In general, lymphoedema occurs together with acute episodes of local inflammation involving skin, lymph nodes and lymphatic vessels due to bacterial infections. Such infections cause elephantiasis, a hardening and thickening of the skin (Burri et al. pp. 671-74). Sometimes men also can suffer from hydrocoele, a fluid-filled enlargement of the sacs around the testes.
Lymphatic filariasis is primarily considered as a disease of the poor as in recent years, this disease has steadily increased because of the expansion of slum areas and poverty, particularly in Africa and the Indian sub-continent. As many filariasis patients are physically incapacitated it further hampers the person’s ability to perform there by reducing his earning capacity. Lymphatic filariasis exerts too much social burden on individual. Due to the diseases in men, genital damage is a severe handicap leading to physical limitations and social stigmatization. In the case of women, shame and taboos are also linked with the disease (WHO n.p. 2000).
Malaria
Malaria is a vector-borne infectious disease caused by protozoan parasites which is widespread in tropical and subtropical regions, including parts of the Americas, Asia, and Africa. Every year, it causes disease in approximately 515 million people and kills between one and three million. It is severe mostly among young children in Sub-Saharan Africa (Snow, pp. 214-217). The causal agent of Malaria is a parasite called Plasmodium, which is transmitted via the bites of infected mosquitoes. Malaria is transmitted to people by mosquitos. The scientific name of the particular type of mosquito is Anopheles. An infected Anopheles mosquito bites a person and injects the malaria parasites into the blood. The parasites multiply in human body in the liver and then infect red blood cells.
Symptoms of malaria include fever, headache, and vomiting, and generally appear between 10 and 15 days after the mosquito bite. It is said that if malaria is not treated immediately, it can become life-threatening by disrupting the blood supply to vital organs. Additionally, today the resistance developed by the parasites to a number of malaria medicines is a major problem.
Malaria is also another disease commonly linked with poverty, but is also a cause of poverty and a major hindrance to economic development. Though there is not any external deformity caused as in the case of Lymphatic filariasis, Malaria is a cause of concern to the economically backward people. In general the costs to individuals and their families include purchase of drugs for treating malaria at home, other hospital expenses and treatment at, lost days of work, absence from school in case of children or teachers; expenses for preventive measures and above all the expenses for burial in case of deaths.
Yellow fever
Yellow fever or jaundice is an acute viral disease (Schmaljohn 1998). It is an important cause of hemorrhagic illness in many African and South American countries. According to the estimates of World Health Organization (WHO) as of 2001, yellow fever causes 200,000 illnesses and 30,000 deaths every year in unvaccinated populations (WHO n.pag 2000). Infection causes a wide spectrum of disease, from mild symptoms to severe illness and death. Even though an effective vaccine has been available for more than 60 years, the number of people infected over the last few decades has increased and yellow fever is now a serious public health concern.
In general it is seen that the virus remains silent in the body during an incubation period of three to six days in the body. There are two distinct phases of the disease called the acute phase and the toxic phase. While some infections have no symptoms whatsoever, the initial, “acute”, phase is generally characterized by fever, muscle pain, prominent backache, headache, shivers, loss of appetite, nausea and/or vomiting. Often, the high fever is paradoxically linked with a slow pulse. After three to four days most patients improve and their symptoms disappear.
Studies have estimated that 15% of the cases enter a “toxic phase” within 24 hours. Fever reappears and several body systems are affected simultaneously. The people with yellow fever rapidly develop jaundice and complain of abdominal pain with vomiting. Bleeding can occur from the mouth, nose, eyes and/or stomach followed by the appearance of blood in the vomit and faeces. Kidney function deteriorates which can range from abnormal protein levels in the urine (albuminuria) to complete kidney failure with no urine production (anuria). In general, half of the patients in the “toxic phase” die within 10-14 days and others recover without significant organ damage (WHO n.pag 2001).
Till date there is no specific treatment for yellow fever. People with yellow fever can combat dehydration and fever with oral rehydration salts and paracetamol. Further, any superimposed bacterial infection should be treated with a suitable antibiotic. In serious cases the patient must be immediately shifted to the nearby hospital. Intensive supportive care may improve the outcome for seriously ill patients. However these facilities are rarely available in poorer, developing countries. Vaccination is the single most important measure for preventing yellow fever especially in the poor countries (WHO n.pag 2001). Though yellow fever does not cause much social stigma in people, it definitely causes economic burden on people. People who are from a weak financial background lose several working days.
Dengue fever
Dengue fever is acute febrile diseases, found in the tropics and Africa, with a geographical spread similar to malaria. However the major difference is that malaria is often eradicated in major cities, whereas dengue is often found in urban areas of developed tropical nations, including Singapore, Taiwan or Brazil. Dengue is caused by one of four closely related virus serotypes of the genus Flavivirus, family Flaviviridae, each serotype is sufficiently different that there is no cross-protection and epidemics caused by multiple serotypes (hyperendemicity) can occur. Dengue is transmitted to humans by the Aedes aegypti (rarely Aedes albopictus) mosquito, which feeds during the day (Wikipedia, 2007). Therefore, it is important to protect oneself from mosquito bites in the day time.
It is an acute illness of sudden onset that usually follows with symptoms of headache, fever, exhaustion, severe joint and muscle pain, swollen glands (lymphadenopathy), and rash. The presence of fever, rash, and headache and other pains is mainly characteristic of dengue. Dengue strikes people with low levels of immunity, especially, those from poor financial background. Since it is caused by one of four serotypes of virus, it is possible to get dengue fever multiple times. Therefore, an attack of dengue produces immunity for a lifetime to that particular serotype to which the patient was exposed and not the other three serotype.
Dengue is widespread all through the tropics and subtropics. Outbreaks have occurred in the Caribbean, including Puerto Rico, the U.S. Virgin Islands, Cuba, and Central America. In general, it is also transmitted from one country to another by the tourists returning from areas with widespread dengue, including Tahiti, the South Pacific, Southeast Asia, the West Indies, India, and the Middle East. According to the World Health Organization, there were 188,684 cases of dengue reported in 2006, with Indonesia having 57% of the reported cases (Cunha and Stöppler).
There is no specific treatment regime for Dengue as the mainstay of treatment is supportive therapy. Patients are recommended to increase oral fluid intake to prevent dehydration. Supplementation with intravenous fluids may be necessary to prevent dehydration and significant concentration of the blood if the patient is unable to maintain oral intake. Additionally, platelet transfusion is indicated in rare cases if the platelet level drops significantly (< 20,000) or if there are significant bleeding. Besides, the presence of melena may indicate internal gastrointestinal bleeding requiring platelet and/or red blood cell transfusion (Cunha and Stöppler).
Rapid spread of dengue in Asia-Pacific Region is especially attributed to globalization, rapid unplanned and unregulated urban development, poor water storage and substandard sanitary conditions. Dengue is mainly a man-made health problem. Other than the risk of death, dengue causes ill health and serious adverse social and economic losses.
In conclusion, if we compare all the four diseases- Filariasis, Malaria, Yellow Fever, and Dengue, it can be said that all the four are diseases common in the developing and underdeveloped countries. Persons most vulnerable are those with no or little protective immunity against the disease. In developing countries, the harmful effects of these diseases may combine with those of other highly prevalent diseases and conditions, such as malnutrition, HIV/AIDS, and anemia of all causes. Such combinations can have severe results, especially if they occur repeatedly. Additionally, since Filariasis is also associated with serious stigma due to physical appearance, people with this disease are comparatively more affected.
Work cited
- Cunha JP and Stöppler MC Dengue Fever MedicineNet, Inc. Web.
- Mortimer PS Investigation and management of lymphoedema, Vas Med Rev (1990) 1:1-20.
- Ottesen EA, Duke BOL, Karam M, et al Strategies and tools for the control/elimination of lymphatic filariasis, Bulletin of the World Health Organization, (1997) 75 (6):491-503.
- Snow RW, Guerra CA, Noor AM, Myint HY, Hay SI. The global distribution of clinical episodes of Plasmodium falciparum malaria. Nature (2005) 434 (7030): 214-217.
- WHO World Health Report. (1998) Geneva: World Health Organization.
- WHO Lymphatic filariasis, Fact sheet N°102, (2000) World Health Organization. Web.
- Wikipedia Dengue fever Wikimedia Foundation, Inc., (2007) Web.