Malaria: Causes, Symptoms, Treatment, and Prevention

Causative Agent

Malaria in humans is caused by four species of the protozoan parasite Plasmodium: P. falciparum, P. vivax, P. ovale, and P. malariae. Among these, P. falciparum is the most infectious and lethal.

Vector

The primary vector for malaria is the female Anopheles mosquito.

Description

Malaria is the most significant tropical parasitic disease globally, causing more deaths than tuberculosis. It has had a devastating impact on many developing countries, particularly in Africa, resulting in numerous fatalities, high medical costs, and significant loss of workdays.

Symptoms

• Attacks of fever
• Anemia
• Chills
• Joint pain
• Headaches

In cerebral malaria, infected red blood cells obstruct brain blood vessels, potentially damaging vital organs and often leading to death.

Transmission

Malaria parasites are transmitted from person to person by female Anopheles mosquitoes. Male mosquitoes do not transmit the disease as they feed exclusively on plant juices. The parasites develop in the mosquito's gut and are transmitted through the saliva during subsequent blood meals. Once in the human host, the parasites travel through the bloodstream to the liver, where they invade cells and multiply.

The spread of malaria is often exacerbated by factors such as:

• Road construction
• Mining
• Sawmill operations
• New agricultural and irrigation projects, especially in developing areas like the Amazon
• Disintegration of health services
• Armed conflicts
• Mass refugee movements

Treatment

Malaria can typically be cured with antimalarial drugs. Symptoms like fever, chills, joint pain, and headache usually resolve quickly once the parasite is eliminated. However, in certain regions, the parasites have developed resistance to some antimalarial drugs, particularly chloroquine. Patients in these areas require treatment with alternative, often more expensive, drugs. Severe cases of malaria, including cerebral malaria, necessitate hospitalization.

In endemic regions with high transmission rates, people are frequently infected and gradually develop immunity to the disease. Children remain particularly vulnerable until they acquire this immunity.

Prevention

Effective malaria prevention requires detailed knowledge of the local vector's ecology and the behavior of people in endemic areas. The challenge of malaria control in tropical countries is compounded by inadequate health infrastructure and poor socioeconomic conditions. The situation has become more complex in recent years due to increased resistance to commonly used antimalarial drugs.