The Chikungunya Virus: Symptoms and Causes

The Chikungunya Virus: Symptoms and Causes Chikungunya virus, also known as Chikungunya fever, is most often found in urban areas of India and also in other countries such as Africa and other regions in Southeast Asia. They tend to appear in very crowded areas, which allow transmission of the virus to be more efficient. It is a single stranded, enveloped RNA virus that is a part of the genus Alphavirus (Riezebos-Brilman). All Alphavirus are transmitted to Humans through infected mosquitoes, which for Chikungunya virus in particular, does not cause as deadly symptoms as does other viruses. Although Chikungunya has not been reported to cause death in Humans, its symptoms can still affect some individuals adversely. These symptoms can be long-lasting; however they seem to eventually disappear. There is not one specific treatment for Chikungunya fever, but it can be treated separately by each symptom (Chikungunya). Even though there are not any specific treatments for Chikungunya fever, there are many prevention methods or strate gies that can be used to avoid mosquitos. In order for Chikungunya virus to gain entrance into Humans, it must first infect mosquitoes. Mosquitoes become infected by biting Humans that are already infected with Chikungunya virus and the mosquitos can then infect Humans who are not infected. Specifically the vector that mainly transmits the infection is the mosquito Aedes aegypti, which are also known as the yellow fever mosquito (Chikungunya). After Aedes aegypti spreads the infection to Humans by biting into the skin, the virus primarily does all of its replication in the cytoplasm. It starts off by attaching its surface protein to the host cells receptor on its plasma membrane where it then enters the cell by endocytosis and transported to endosomes. Uncoating of the capsid occurs by acidification which involves a change in pH eventually causing the capsid to uncoat. The capsid is a regular, icosahedral, twenty-faced structure that holds the genome. The genome is comprised of a positive single-stranded RNA, which is theref ore classified as Baltimore class IV. When the genome is free of the capsid, it can skip transcription and go straight to mRNA processing (because it is a positive strand) and translation in the cytoplasm. A crucial step that initiates translation involves eIF2-alpha, which allows normal-house keeping genes to shut off. Also, during translation, the first ORF is translated, which encodes for four particular proteins (nsP1, nsP2, nsP3 and nsP4) that makes replicase (a viral protein). Replicase forms the negative strand intermediate (42S RNA) and which will then in turn create more positive stranded RNA. After translation, the capsid is assembled by ribosomes and the lipid-protein envelope (only proteins in envelope are glycoproteins) is assembled at the plasma membrane where it egresses the cell by budding (Riezebos-Brilman). Upon replication of Chikungunya virus, there are many symptoms and diseases that affect Humans. Most symptoms start to show within one to twelve days and sometimes symptoms do not even show. One of the most common symptoms that first appears is fever (which is why is it commonly known as Chikungunya fever). Fevers can be as high as 104ÂÂ °F, which can last from days to weeks. Other common symptoms that appear in the beginning of infection are fever, chills, vomiting, joint pain, headaches, vomiting, swelling of joints, bleeding/hemorrhage, fatigue, muscle pain, and rash (Bhowmikb). One symptom in particular that is the most often seen symptom is arthritis. The word Chikungunya comes from an African root that means bend over, which is refers to arthritis (Just The Facts: Chikungunya). Even though almost all of these symptoms can be prolonged (days to weeks to even months), they eventually disappear. The virus lipid envelope is what allows the immune system to detect it. The symptoms are very similar to Dengue, which is seen in the same areas as where Chikungunya virus is present and also which is why Chikungunya virus is often misdiagnosed as Dengue. The only way to differentiate the difference between Dengue and Chikungunya virus is by performing a blood test (ELISA), which can be time consuming. Although it is important that the two diseases are distinguished from one another, many doctors use the symptoms to distinguish between the two viruses simply for the fact because blood testing takes too long (Chikungunya). Even after diagnoses, the virus or disease cannot be treated because there is no vaccine or a particular antiviral treatment. For the most part, symptoms are individually treated and medications such as ibuprofen, paracetamol, or naproxen are suggested to relive symptoms of fever, headaches, aching. Often times NSAIDA pills are given to those who are infected to treat only certain symptoms. There have been a few clinical trials in the making. One for example, is a prototype vaccine that has been successful in monkeys, but will soon be tested on Humans later this year. The vaccine is live and it allows the immune system to recognize the outer layer of the virus but does not allow the immune system to recognize the virus genome (which essentially prevents replication from occurring). They then isolated antibodies from the virus and put them into mice, which were also protected against the virus (Maugh). Since there are only clinical trials in the making as of now and since there is not one specific treatment, it is highly recommended, that fluids are frequently taken. An abundance of rest is also recommended and also infected people should avoid staying out doors from other potential mosquito exposure. Avoiding potential mosquito exposure will essentially help to avoid transmission rate in a given region to rise. It is a good idea to have prevention methods in mind since there is not a specific treatment for Chikungunya fever. An example of a prevention method is using mosquito repellents containing DEET (Bhowmikb) or Picaridin on clothes and on the skin. Also when staying indoors, a well-netted/screened area or air conditioned areas would help prevent transmission. When outdoors, on the other hand, wearing long clothing that covers most of the skin can help prevent mosquito bites. Also, getting clear of any source of mosquitos around living areas would help prevent mosquito existence vastly. Areas such as birdbaths, standing water from flowering pots, barrels, and pet dishes would clear a large source of mosquitoes (Chikungunya). Large sources where mosquitoes usually exist are urban areas because Humans are good reservoirs for the virus. Those areas that are especially surrounded with poverty, environmental tragedies (such as natural disasters), tropical climate predominantly year round, and areas where public health is corrupted are prime spots for mosquitos and are also good spots for a virus to transmit by mosquito-Human-mosquito. Many third world countries are targets for Chikungunya fever. Countries such as India, Pakistan, South Africa, and the Philippines have been seen with problems with this particular disease. In areas where there is an abundance of mosquitos and where poverty has flourished, nets or screens are usually used to prevent mosquitos from entering households. Since there is an abundance of the disease in third world countries, there is an issue of money. Most of these countries cannot afford to provide every household with screening or net and therefore transmission becomes easier. Not only is location an issue but demographic is also. Anyone who is bitten by a mosquito is at risk for being infected, but some people show symptoms more than others. For instance, some individuals do not show any symptoms. This is primarily seen in children. Pregnant women can be at risk for passing it to their children. They can be infected at any time of their pregnancy but they are usually only at risk for passing it to their child if it is in their bloodstream during the time of delivery. Also, mortality rate is very low and is rarely seen but it does increase with increasing age. Perhaps the reason why Chikungunya fever is a problem in various countries around the world is due to the fact that there is no actual treatment and there is only medicine available to help ease the symptoms. Also it seems as if there have been various clinical trials (Dwivedi) arising due to a recent rising epidemic in countries such as India and South Africa. Though this virus is not viewed as detrimental compared to other viruses to populations because of low mortality rate, it still has been arising symptomatic problems in certain people, such as those who experience joint pains or swelling of joints for years (Chikungunya). Not only are the symptoms themselves a problem, but the fact that they can last for so long and they that they can cause multiple symptoms at one time. Since the virus does tend to show up frequently in third world countries money tends to be an issue. There are so many families whom come from poverty and cannot afford to pay for medication that requires to be taken over such a long period of time. Therefore if there were a specific treatment for Chikungunya virus, then maybe is would not be an epidemic in certain countries.