https://encrypted-tbn0.google.com/images?q=tbn:ANd9GcSpzp85jtunte19_0BbNbP583vQyhTuhm8ms6o1dE3U41hENzjW

25 April, 2012

Text Box: SUSTAIN GAINS, SAVE LIVES

 

By

Dr. Asad Ali

Faculty of Agriculture, AWKUM, Anbar, Swabi

 

https://encrypted-tbn3.google.com/images?q=tbn:ANd9GcS3R1L0kQ0frz2bkAG8TXPnhgVKIULl5CfeBOxwgXXwjhg1vmFX Malaria is a parasitic disease caused by Plasmodium and transmitted by Anopheles mosquito. Malaria involves high fevers, shaking chills, flu-like symptoms, and anemia.

 

Causes, incidence, and risk factors

Malaria is caused by a parasite that is passed from one human to another by the bite of infected Anopheles mosquitoes. After infection, the parasites (called sporozoites) travel through the bloodstream to the liver, where they mature and release another form, the merozoites. The parasites enter the bloodstream and infect red blood cells.

The parasites multiply inside the red blood cells, which then break open within 48 to 72 hours, infecting more red blood cells. The first symptoms usually occur 10 days to 4 weeks after infection, though they can appear as early as 8 days or as long as a year after infection. The symptoms occur in cycles of 48 to 72 hours.

Most symptoms are caused by:

·         The release of merozoites into the bloodstream

·         Anemia resulting from the destruction of the red blood cells

 

·         Large amounts of free hemoglobin being released into circulation after red blood cells break open

  Malaria can also be transmitted from a mother to her unborn baby (congenitally) and by blood transfusions. Malaria can be carried by mosquitoes in temperate climates, but the parasite disappears over the winter.

The disease is a major health problem in much of the tropics and subtropics. The WHO estimates that there are 300-500 million cases of malaria each year, and more than 1 million people die from it. It presents a major disease hazard for travelers to warm climates.

In some areas of the world, mosquitoes that carry malaria have developed resistance to insecticides. In addition, the parasites have developed resistance to some antibiotics. These conditions have led to difficulty in controlling both the rate of infection and spread of this disease.

There are four types of common malaria parasites. Recently, a fifth type, Plasmodium knowlesi, has been causing malaria in Malaysia and areas of southeast Asia. Another type, falciparum malaria, affects more red blood cells than the other types and is much more serious. It can be fatal within a few hours of the first symptoms.

 

Symptoms

 

·         Anemia

·         Bloody stools

·         https://encrypted-tbn2.google.com/images?q=tbn:ANd9GcRG0NZfyWEdLzOVrkGD2a2e6w61a98aXQfodAJ5pBN0ObHgTZpN Chills

·         Coma

·         Convulsion

·         Fever

·         Headache

·         Jaundice

·         Muscle pain

·         Nausea

·         Sweating

·         Vomiting

 

Signs and tests

 

During a physical examination, the doctor may find an enlarged liver or enlarged spleen. Malaria blood smears taken at 6 to 12 hour intervals confirm the diagnosis.

complete blood count (CBC) will identify anemia if it is present.

 

Treatment

Malaria, especially Falciparum malaria, is a medical emergency that requires a hospital stay. Chloroquine is often used as an anti-malarial medication. However, chloroquine-resistant infections are common in some parts of the world.

Possible treatments for chloroquine-resistant infections include:

·         The combination of quinidine or quinine plus doxycyclinetetracycline, or clindamycin

·         Atovaquone plus proguanil (Malarone)

·         Mefloquine or artesunate

·         The combination of pyrimethamine and sulfadoxine (Fansidar)

The choice of medication depends in part on where you were when you were infected.

Medical care, including fluids through a vein (IV) and other medications and breathing (respiratory) support may be needed.

Expectations (prognosis)

The outcome is expected to be good in most cases of malaria with treatment, but poor in Falciparum infection with complications.

Complications

·         Brain infection (cerebritis)

·         Destruction of blood cells (hemolytic anemia)

·         Kidney failure

·         Liver failure

·         Meningitis

·         Respiratory failure from fluid in the lungs (pulmonary edema)

·         Rupture of the spleen leading to massive internal bleeding (hemorrhage)

 

Prevention

 

Most people who live in areas where malaria is common have gotten some immunity to the disease. Visitors will not have immunity, and should take preventive medications.

The types of anti-malarial medications prescribed will depend on the area you visit.

·         Chloroquine has been the drug of choice for protecting against malaria. But because of resistance, it is now only suggested for use in areas where Plasmodium vivaxP. oval, and P. malariae are present. Falciparum malaria is becoming increasingly resistant to anti-malarial medications.

People who are taking anti-malarial medications as preventive measure may still become infected. The best way is to avoid mosquito bites by

·         wearing protective clothing over the arms and legs,

·         using screens on windows, and

·         using insect repellent.

References

1.    Fairhurst RM, Wellems TE. Plasmodium species (Malaria). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 275.

2.    Krogstad DJ. Malaria. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier. 2007:chap 366.

 

Acknowledgements: Thanks to Dr. M. Faisal Anwar Malik and Dr. Muhammad Qasim