Eradicating or Mitigating Malaria - Coursework Example

Running header: Assignment- Malaria Student’s name: Name of institution: Instructor’s name: Course code: Date of submission: Introduction- brief background information and justification Malaria is an infectious disease that is caused by a parasite known as plasmodium (Packard, 2007). Malaria is usually carried and transmitted through the bite of an infected female mosquito (Webb, 2009). Malaria usually affects humans and it is caused by eukaryotic protists that belong to the genus plasmodium. It is usually one of the oldest and most common infectious diseases known to occur in human beings (Shah, 2010). Hundreds of millions of people are disabled by malaria throughout the world every year. In the human body, the malaria parasites are known to multiply in the liver, after which they affect the red blood cells. Malaria is very common in the tropical and subtropical regions of the world. It is also widespread in Asia, America and Sub-Saharan Africa (Sutherland, et el 2010). The consistently high temperatures and significant amounts of rainfall are the main conditions that make malaria more prevalent in these regions. High humid conditions coupled with consistent temperatures and the availability of stagnant water enables the mosquito larva to mature (Kilama, & Ntoumi, 2009). This provides the mosquito with the ideal environment that they need to continuously breed. Malaria was discovered by Charles Louis Alphonse Laveran in 1880 (Juma, 2011). Charles Louis Alphonse Laveran was working in the military hospital in Constantine, Algeria when he keenly observed a blood smear of a patient who had just died as a result of malaria so as to look for parasites (Sutherland & Hallett, 2009). The human blood cells that are affected by the disease are the red blood cells. After an infected female mosquito bites a person, the symptoms of malaria usually start to appear after 10-15 days (Fernando, Rodrigo & Rajapakse, 2010). The disease can sometimes get to life-threatening levels, especially if not treated on time. This is because it is known to disrupt the supply of blood to into the vital organs of the human body. Some of the symptoms that are exhibited by humans suffering from malaria include headache, fever and vomiting. As reported earlier, if malaria is not treated on time, it may get to the point where it causes death in humans (Suh, 2005). People have been engaged in a lot of efforts to try and reduce the transmission of the disease (Freedman, 2008). Such efforts have included distributing inexpensive mosquito nets, use of insect repellants when in areas that malaria is prevalent, spraying insecticides inside houses so as to kill the mosquitoes carrying the malaria parasite and draining stagnant waters that are known to be ideal breeding ground for mosquitoes because they lay their eggs under such conditions (Day, 2008). All these measures have one thing in common in that they are aimed at reducing and preventing the amount of mosquitoes available to bite someone. There is a variety of malaria medication that is available for the treatment of malaria (Sesay, Milligan, Touray & Sowe, 2011). However, in some regions of the world, the malaria parasites have developed resistance to most of these malaria medicines. The disease is caused by a protozoan. Severe malaria is largely caused by Plasmodium falciparum (Pates & Curtis, 2005). The world malaria report of 2010 released by World Health Organization (WHO) reveals that there are more than 225 million reported cases of malaria each year. This kills close to 781,000 people on an annual basis (Sutherland, et el 2010). This accounts for 2.23% of the total deaths that occur in the world on annually. Generally, malaria parasites multiply within the liver and move to the red blood cells where they weaken the body and further multiply. Malaria is important because of the magnitude of the disease (Kilama, & Ntoumi, 2009). It is linked to very many health complications and is known to be the cause of very many deaths every year. It is therefore very important to understand malaria, its causes, it symptoms and ways through which its spread can be controlled. This is the only way that we can be sure of having the ability to control the disease and reduce the impact of the disease to our society (Sutherland & Hallett, 2009). This paper discusses in details, the causative agent of malaria and gives factual information about the disease on different levels in the human body such as on the whole organism and the cellular level. The paper also gives ways of diagnosing the disease and the challenges of doing this. It finally discusses therapy of the disease and the effects on the cells. Causative agent or aetiology of disease The causative agent of malaria is a parasite. The parasite is called plasmodium (Suh, 2005). The plasmodium parasite is carried and transmitted to human by the female anopheles mosquito. As the causative agent of malaria in humans, the plasmodium protozoan is known to have four different species namely: plasmodium falciparum, plasmodium vivax, plasmodium ovale and plasmodium malariae (Fernando, Rodrigo & Rajapakse, 2010). Out of the four different species of plasmodium, the plasmodium falciparum is responsible for most of the malaria infections in man and is known to be the most lethal and dangerous. The causative agent was identified in 1880 by Charles Louis Alphonse Laveran. He was working in a hospital when he keenly observed a blood smear of a patient who had just died as a result of malaria. He identified the causative agent as he was looking for parasites (Freedman, 2008). The causative agent interacts with the host through the female anopheles mosquito. The female anopheles mosquito comes into contact with the human body and pierces the epithelium of the host. At this time, the female anopheles mosquito is interested in obtaining its food in form of a blood meal. In the process, it releases plasmodium falciparum into the human blood stream (Day, 2008). This plasmodium falciparum protozoan is contained in the salivary glands of the female anopheles mosquito. At the time when the female anopheles mosquito injects the plasmodium falciparum into the human blood stream, the protozoan is in the sporozite stage in the life cycle of the entire pathogen. Human beings are the reservoirs of plasmodium falciparum. This means that the female anopheles mosquito must have acquired the protozoan from another human being almost nine to seventeen day before as it was looking for its blood meal. This is the only way it is able to transmit the disease to another host (Packard, 2007). The host will therefore have sporozites of the pathogen in the blood stream and is now likely to be infected with malaria after some days (Sutherland, et el 2010). Disease information- whole organism level In some cases, the disease is known to be endemic and this normally makes the host to respond poorly to the malaria. Inadequate immune responses in the host’s body are the major cause of deaths due to malaria (Packard, 2007). Plasmodium falciparum sometimes has the ability to evade the human immune system. This is because plasmodium falciparum has multiple morphologies in their life cycles while they are inside the human body. This allows it to keep changing surface antigens. The protozoan also leaves a portion of its life within the cells found in the liver and the red blood cells (Sutherland, et el 2010). The symptoms of malaria are normally seen on the body when the merozites are released into the blood stream and they attack the red blood cells. These symptoms of malaria usually reside on a 48 hour cycle. It is in this cycle that the most serious symptoms of malaria are seen. In some cases, the body of the host is said to contribute greatly to the pathology of the parasite. This takes place when the host’s body releases excessive tumor necrosis factor (TNF) and interleukin. This causes sickness in the form of malaria (Fernando, Rodrigo & Rajapakse, 2010). At the whole body level, the disease has various symptoms on the host including fever, vomiting, anemia, shivering, hemoglobinuria, convulsions, arthralgia and retinal damage (Sutherland, et el 2010). The classic symptom of malaria however is the cyclical occurrence of sudden coldness. This is usually followed by rigor. Fever and sweating then occur for every 36 to 48 hours (Fernando, Rodrigo & Rajapakse, 2010). These symptoms are known to be worse in children because they are more affected by the disease as compared to adults. They sometimes experience abnormal posturing and severe brain damages as a result of malaria (Suh, 2005). Disease information- organ/tissue/cellular level Once the sporozites have been transmitted into the host’s body via the epithelia, they travel via the host’s blood stream and straight to the liver. Once they reach the host’s liver, they proceed to enter the cells of the liver and stay there for a period of 8-14 days. During this period, they mature into schizonts (Sutherland, et el 2010). Before maturity, the sporozites are covered with a protein that is known as circumsporozite. This protein is responsible for mediating the adhesion of the sporozite to hepatocytes. The schizonts are released into the host’s blood stream as merozites. This is done after a week or so (Fernando, Rodrigo & Rajapakse, 2010). They enter into the red blood cells which spread them to the entire body of the host and cause the host to start experiencing symptoms of the disease after which the disease may become fully blown. The merozites that attack the red blood cells are then said to multiply asexually after which they undergo further maturity and become ring-shaped trophozites within the blood stream of the host (Packard, 2007). In most cases, once the plasmodium falciparum parasite is inside the body of the host, it becomes difficult for the host to be able to defend himself or herself from having full blown malaria unless he or she had taken some anti-malaria medication (Shah, 2010). This is because the parasite lodge themselves on the liver of the host after which they find their way to the red blood cells, therefore making the host’s body weak and unable to defend itself from infection because the body’s defense mechanism has been attacked (Sutherland, et el 2010). However, this does not cause permanent changes to the host’s cells because malaria can be treated and the parasites are destroyed. The cells will therefore go back to their normal functioning. The cellular features sought for diagnosis simply include the structures of the parasite. It is the structure of the parasite that is sought after in blood samples during diagnosis so as to determine whether a person is suffering from malaria or not (Freedman, 2008). Once the plasmodium falciparum has entered the red blood cells, some of it may differentiate into gametocytes. These gametocytes multiply sexually. When a female anopheles mosquito is taking a blood meal from the cells of such a human reservoir, the gametocytes are ingested by the mosquito (Fernando, Rodrigo & Rajapakse, 2010). Once inside the mosquito, the female and male gametocytes produce zygotes. The zygotes further develop into oocytes within the guts of the female anopheles mosquito (Sutherland, et el 2010). The oocytes are responsible for the production of the sporozites which will be moved to the salivary glands of the anopheles mosquito (Sutherland & Hallett, 2009). This completes the life cycle of the plasmodium falciparum and it can then be transmitted to another person as the female anopheles mosquito is taking a blood meal from another person. This is how the entire cycle continues and malaria is spread from one person to the next (Kilama, & Ntoumi, 2009). Diagnostic methods- efficacy, advantages, constraints and/or problems The most common way that malaria is diagnosed is through microscopically examining blood. Blood has been the most common agent being examined in the diagnosis of malaria but urine and saliva have also been in use as alternatives to blood when diagnosing malaria. The examination of blood films is the most reliable, preferred and economic method of diagnosing malaria (Kilama, & Ntoumi, 2009). This is because all the four major parasites of malaria have distinguishing features and characteristics. Traditionally, two sorts of blood films are usually used. These are thin films and thick films. The thin films are the same as usual blood films. They allow species to be identified because of the appearance of the parasites. The thick films on the other hand allow the microscopists to view and screen larger volumes of blood. These thick films are about eleven times more sensitive compared to the thin films (Freedman, 2008). It is therefore easier to pick up low levels of infection using the thick films. However, one disadvantage is that the appearance of the parasite is so much distorted that it becomes difficult to distinguish between the different species of the parasite (Packard, 2007). It may not be easy to tell exactly which parasite is in the blood sample because they have been distorted by the magnification. The use of blood films however remains the most efficient diagnosis of malaria and it is advantageous because it is very reliable and fairly cheap compared to other methods. With blood tests, it is also easier to detect the levels of the parasites that have infected the blood of the host. In other words, it is easy to determine the extent to which the host is infected by the malaria parasites (Fernando, Rodrigo & Rajapakse, 2010). Antigen tests can also be used to diagnose malaria in cases where microscopy is not available. Laboratory staffs who do not know how to effectively diagnose malaria using the blood films can use antigen tests. These are commercial tests which require a drop of blood where the blood is dropped on a dip stick and the kit automatically conducts the teat on its own for around 15 to 20 minutes. The results of the test can then be visually read through observing the presence or absence of colored strips on the dip stick (Kilama, & Ntoumi, 2009). The use of antigen tests is advantageous because it is very convenient to use them in the field since they are easy to carry and use kits. Another advantage is that the threshold for detection of parasites with the antigen kits is much higher because it is in the range of 100 parasites per µ of blood. The greatest disadvantage of the antigen tests to diagnose malaria is that the dip sticks are usually qualitative and not quantitative. This means that the dip sticks can only determine of the parasites are available in the human blood. They can however not determine the quantity or level of infection of the blood by the parasites. This means that they cannot tell how many parasites are available in the blood (Freedman, 2008). Another method that can be used to diagnose malaria is the molecular method. These methods are found in some clinical laboratories. PCR is one of the molecular methods which is more accurate than microscopy (Killeen, Chitnis, Moore, & Okumu, 2011). Accuracy is one advantage of the molecular systems. The disadvantage of such methods such as PCR is that it is a very expensive method. It is not cheap to conduct these tests, therefore making people avoid it unless they can afford it (Kilama, & Ntoumi, 2009). Therapy- effects on cells and tissues Malaria has very few therapeutic effects on the body of the host. This is because most strains of malaria can be treated by therapeutic drugs. Even though drug treatment of malaria is not always easy, it is safe (Sutherland, et el 2010). Most strains of malaria have become resistant to drugs but ne drugs that are strong enough are being developed to ensure that malaria is dealt with accordingly. There are many harmless therapies and preventive measures that can be used to prevent and treat malaria. One of these methods is the application of repellents which will discourage mosquitoes from biting a person (Kilama, & Ntoumi, 2009). This method does not harm the cells in any way because it is done externally. The repellent is applied on the skin so as to keep mosquitoes away. The use insecticides such as mosquito coils, aerosol insecticides and vaporizing mats are used to keep mosquitoes away from rooms (Fernando, Rodrigo & Rajapakse, 2010). Direct inhalation of these insecticides may have adverse effects to the cells of human beings. Bed nets are also one of the most effective methods of screening mosquitoes and keeping them away from the body. They have little or no effect on the cell but one should ensure that they can breathe well and is not suffocated by the nets (Packard, 2007). Conclusion Understanding malaria is one of the most important steps towards eradicating or mitigating it. There has been a lot of research in the field of malaria with the sole aim of coming up with proper and workable vaccines that will ensure it is prevented from spreading and killing people. As seen in the essay, malaria is the world’s most important parasitic disease. Malaria is a disease that kills more people than any other known communicable disease apart from tuberculosis. In many African countries and other developing regions of the world, malaria is known to have adverse effects on the lives of people by increasing the medical costs or the days of labor that have been lost. The disease is still very prevalent and is still a threat to the lives of many individuals unless it is fully taken care of. Researchers and scientists have been engaged in constant efforts to try and come up with an effective and inexpensive vaccine to prevent the spread of the disease. More than 90 countries of the world inhabited by 2,400,000 consider malaria a public health problem. This translates to about 40% of the world’s total population. There have been various interventions and breakthroughs in the understanding of malaria. The World Health Organization (WHO) has made tremendous steps towards the prevention and treatment of malaria. For example, the WHO has come up with four basic technical elements which are part of their global malaria control strategy. The first technical element that they have identified entails providing early diagnosis to the disease and ensuring prompt treatment. The second basic technical element is the planning and implementing of selective and sustainable measures of preventing the disease such as vector control. The WHO also recommends early detection of the disease so as to enable its prevention and the containment of any epidemics that may arise as a result of the disease. The World Health Organization (WHO) finally proposes and supports the strengthening of the capacity of local research initiatives. This is done through promoting regular assessment of the malaria situations in various countries. This entails examination of the economic, social and ecological determinant of the disease so as to come up with viable ways of mitigating it and its effects. References Day, N. (2008). 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