As You all know that Malaria has been spread over lots of areas around pakistan please have some know how about this disease and take some precautionary measures ... below text is taken from wikipedia .. i have selected most important part of it .. we should all be educated and should educate others about it..
Signs and symptoms from Wikipedia
Symptoms of malaria include fever, shivering, arthralgia (joint pain),vomiting, anemia (caused by hemolysis), hemoglobinuria, retinal damage,[14] and convulsions. The classic symptom of malaria is cyclical occurrence of sudden coldness followed by rigor and then fever and sweating lasting four to six hours, occurring every two days in P. vivax andP. ovale infections, while every three days for P. malariae.[15] P. falciparum can have recurrent fever every 36–48 hours or a less pronounced and almost continuous fever. For reasons that are poorly understood, but that may be related to high intracranial pressure, children with malaria frequently exhibit abnormal posturing, a sign indicating severe brain damage.[16] Malaria has been found to cause cognitive impairments, especially in children. It causes widespread anemia during a period of rapid brain development and also direct brain damage. This neurologic damage results from cerebral malaria to which children are more vulnerable.[17][18] Cerebral malaria is associated with retinal whitening,[19]which may be a useful clinical sign in distinguishing malaria from other causes of fever.[20]
Severe malaria is almost exclusively caused by P. falciparum infection, and usually arises 6–14 days after infection.[21] Consequences of severe malaria include coma and death if untreated—young children and pregnant women are especially vulnerable. Splenomegaly (enlarged spleen), severeheadache, cerebral ischemia, hepatomegaly (enlarged liver),hypoglycemia, and hemoglobinuria with renal failure may occur. Renal failure is a feature of blackwater fever, where hemoglobin from lysed red blood cells leaks into the urine. Severe malaria can progress extremely rapidly and cause death within hours or days.[21] In the most severe cases of the disease, fatality rates can exceed 20%, even with intensive care and treatment.[22] In endemic areas, treatment is often less satisfactory and the overall fatality rate for all cases of malaria can be as high as one in ten.[23] Over the longer term, developmental impairments have been documented in children who have suffered episodes of severe malaria.[24]
Pathogenesis
Malaria develops via two phases: an exoerythrocytic and an erythrocytic phase. The exoerythrocytic phase involves infection of the hepatic system, or liver, whereas the erythrocytic phase involves infection of the erythrocytes, or red blood cells. When an infected mosquito pierces a person's skin to take a blood meal, sporozoites in the mosquito's saliva enter the bloodstream and migrate to the liver. Within minutes of being introduced into the human host, the sporozoites infect hepatocytes, multiplying asexually and asymptomatically for a period of 8–30 days.[38]Once in the liver, these organisms differentiate to yield thousands ofmerozoites, which, following rupture of their host cells, escape into the blood and infect red blood cells, thus beginning the erythrocytic stage of the life cycle.[38] The parasite escapes from the liver undetected by wrapping itself in the cell membrane of the infected host liver cell.[39]
Within the red blood cells, the parasites multiply further, again asexually, periodically breaking out of their hosts to invade fresh red blood cells. Several such amplification cycles occur. Thus, classical descriptions of waves of fever arise from simultaneous waves of merozoites escaping and infecting red blood cells.
Diagnosis
The mainstay of malaria diagnosis has been the microscopic examination of blood.[47] Although blood is the sample most frequently used to make a diagnosis, both saliva and urine have been investigated as alternative, less invasive specimens.[48]
Areas that cannot afford laboratory diagnostic tests often use only a history of subjective fever as the indication to treat for malaria. Using Giemsa-stained blood smears from children in Malawi, one study showed that when clinical predictors (rectal temperature, nailbed pallor, and splenomegaly) were used as treatment indications, rather than using only a history of subjective fevers, a correct diagnosis increased from 2% to 41% of cases, and unnecessary treatment for malaria was significantly decreased.[49]
Prevention
Methods used in order to prevent the spread of disease, or to protect individuals in areas where malaria is endemic, include prophylactic drugs, mosquito eradication and the prevention of mosquito bites.
The continued existence of malaria in an area requires a combination of high human population density, high mosquito population density and high rates of transmission from humans to mosquitoes and from mosquitoes to humans. If any of these is lowered sufficiently, the parasite will sooner or later disappear from that area, as happened in North America, Europe and much of the Middle East. However, unless the parasite is eliminated from the whole world, it could become re-established if conditions revert to a combination that favours the parasite's reproduction.[citation needed] Many countries are seeing an increasing number of imported malaria cases owing to extensive travel and migration.
Medications
Several drugs, most of which are also used for treatment of malaria, can be taken preventively. Chloroquine may be used where the parasite is still sensitive.[60] However due to resistance one of three medications: mefloquine (Lariam),doxycycline (available generically), and the combination of atovaquone and proguanil hydrochloride (Malarone) is frequently needed.[60] Doxycycline and the atovaquone and proguanil combination are the best tolerated with mefloquine associated with higher rates of neurological and psychiatric symptoms.[60]
Indoor residual spraying
Indoor residual spraying (IRS) is the practice of spraying insecticides on the interior walls of homes in malaria affected areas. After feeding, many mosquito species rest on a nearby surface while digesting the bloodmeal, so if the walls of dwellings have been coated with insecticides, the resting mosquitos will be killed before they can bite another victim, transferring the malaria parasite.
The first pesticide used for IRS was DDT.[62] Although it was initially used exclusively to combat malaria, its use quickly spread to agriculture. In time, pest-control, rather than disease-control, came to dominate DDT use, and this large-scale agricultural use led to the evolution of resistant mosquitoes in many regions. The DDT resistance shown by Anopheles mosquitoes can be compared to antibiotic resistance shown by bacteria.
Mosquito nets and bedclothes
Mosquito nets help keep mosquitoes away from people and greatly reduce the infection and transmission of malaria. The nets are not a perfect barrier and they are often treated with an insecticide designed to kill the mosquito before it has time to search for a way past the net. Insecticide-treated nets (ITNs) are estimated to be twice as effective as untreated nets and offer greater than 70% protection compared with no net.[72] Although ITNs are proven to be very effective against malaria, less than 2% of children in urban areas in Sub-Saharan Africa are protected by ITNs. Since theAnopheles mosquitoes feed at night, the preferred method is to hang a large "bed net" above the center of a bed such that it drapes down and covers the bed completely.
Vaccination
Immunity (or, more accurately, tolerance) does occur naturally, but only in response to repeated infection with multiple strains of malaria.[73] Vaccines for malaria are under development, with no completely effective vaccine yet available. The first promising studies demonstrating the potential for a malaria vaccine were performed in 1967 by immunizing mice with live, radiation-attenuated sporozoites, providing protection to about 60% of the mice upon subsequent injection with normal, viable sporozoites.[74] Since the 1970s, there has been a considerable effort to develop similar vaccination strategies within humans. It was determined that an individual can be protected from a P. falciparum infection if they receive over 1,000 bites from infected yet irradiated mosquitoes.[75]
[edit]Other methods
Education in recognizing the symptoms of malaria has reduced the number of cases in some areas of the developing world by as much as 20%. Recognizing the disease in the early stages can also stop the disease from becoming a killer. Education can also inform people to cover over areas of stagnant, still water e.g. Water Tanks which are ideal breeding grounds for the parasite and mosquito, thus cutting down the risk of the transmission between people. This is most put in practice in urban areas where there are large centers of population in a confined space and transmission would be most likely in these areas.
Treatment
When properly treated, a patient with malaria can expect a complete recovery.[
--
Please visit www.vuzs.net For Current & Old Papers, Quizzes, Assignments and study material.
--
You received this message because you are subscribed to the Google
Groups "vuZs" group.
--
To post a new message on this group, send email to vuZs@googlegroups.com
--
Message Posting Rules: http://vuzs.net/faq/4795-vuzs-google-groups-basic-rules-for-posting-messages.html
--
To unsubscribe from this group, send email to vuZs+unsubscribe@googlegroups.com
--
To join this group Send blank email from your virtual university email address to
vuZs+subscribe@googlegroups.com
or visit
http://groups.google.com/group/vuZs/subscribe
---
For more information Contact vuZs Manager at info@vuzs.net
No comments:
Post a Comment