Malaria is a mosquito-borne infectious disease caused by various species of the parasitic protozoan microorganism called Plasmodium. Malaria is a disease that man has battled with for a long time. It is even thought to have brought the Roman Empire to its knees. Malaria was so prevalent during the Roman times that the disease is also called ‘Roman Fever’.Causes of Malaria
- Bitten by an infected mosquito.
- Use of shared and infected syringes.
- Organ transplantation.
- From an infected mother to her baby during birth.
Symptoms of malaria
- It includes fever, fatigue, chills, vomiting, and headaches.
- Diarrhea, anemia, muscle pain.
- Profuse sweating and convulsions.
- Bloody stools.
- In severe the cases, malaria can be devastating; seizures, coma and finally death.
It is due to the efforts of a physician, Sir Ronald Ross, we today know that Malaria is caused by a protozoan parasite which is transmitted by infected mosquitoes. His deep research showed that specifically the female Anopheles stephensi mosquito or female Anopheles mosquito is the vector of the disease which enabled us to address the problem directly and save thousands of lives.
Malaria Life Cycle
Malaria parasite exists in the form of a motile sporozoite. The vector of malaria i.e. the female Anopheles mosquito transmits the malarial sporozoites into the hosts. When an infected mosquito bites a human, the sporozoites are injected into the blood through the mosquito’s saliva. The sporozoites travel into our body and accumulate in the liver. These parasites initially multiply within the liver, by damaging the liver and rupturing the blood cells in the body. The main weapon of malaria is its destruction of the red blood cells. The parasites reproduce asexually in the RBCs, bursting the cells and releasing more parasites to infect more cells. The rupture of red blood cells by the malaria parasite releases a toxin called hemozoin which causes the patient’s chills.
When the female Anopheles mosquito bites an infected human, the parasites enter the mosquito’s body along the human blood it is drinking. It is inside the mosquito’s body that the actual development and maturing of the parasite happens. The parasites produced in the human body reach the intestine of the mosquito where the male and females cells fertilize each other to lead to the formation of a sporozoite. On maturing, the sporozoite breaks out the mosquito’s intestine and migrate to the salivary glands. Once they reach salivary glands, they wait till the mosquito bites another human and the process of infection and disease begins all over again. It is prudent however to observe that the complete development of the malaria parasite takes place in two different hosts; humans and mosquitoes.
Prevention of malaria
Malaria is one of the major causes of preventable death in the world today. It affects more than 500 million people worldwide and causes 1 to 2 million deaths every year. It is a tropical infectious disease. The work to develop a malaria vaccine is an important tool for the future generations and is ongoing. There is two-way to deal with malaria, prevent a mosquito bite i.e preventative steps or attack the parasites once they have infiltrated our body.
The first method advocates the use of mosquito nets and mosquito repellent such as permethrin to prevent mosquitoes from biting you. The second form of treatment uses a chemical called Quinine present in the bark of a cinchona tree. A form of drug chloroquine has proven very effective against malaria though not a vaccine.
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