Definition and Overview

Malaria is a serious, life-threatening mosquito-borne disease that infects a person’s blood with parasites. It can be caused by a single mosquito bite and can lead to fatal results when not promptly diagnosed and treated. Thus, it is important to recognize its symptoms at the soonest possible time. These symptoms include high fever, headache, muscle pain, diarrhea, and vomiting.

The symptoms of malaria may begin to manifest within 1 to 3 weeks after infection, but there are cases wherein the symptoms only appear after a year, with the parasite initially lying dormant in the patient’s body. Thus, if the symptoms are observed within a one to two-year period of suspected exposure or visit to areas where malaria outbreaks have been reported, medical attention is highly advised.

Causes of Condition

Malaria is mainly caused by a parasite called Plasmodium, which is transmitted by Anopheles mosquitoes, particularly the female ones that thrive in tropical and subtropical climates. A mosquito carrying the Plasmodium parasite can instantly pass it on to a person’s bloodstream with a single bite. Once in the bloodstream, the parasite will travel to the liver and, from there, infect the red blood cells causing them to burst, at which point symptoms begin to manifest. These mosquitoes typically bite from sundown to nighttime. Although Plasmodia parasites come in many different types, only five of them can cause malaria among humans.

It is also possible to contract malaria through a blood transfusion, an organ transplant, and the use of an infected needle, but such cases can be easily avoided and are therefore quite rare.

A person’s risk of getting bitten by a parasite-carrying mosquito and become infected with malaria is affected by very specific factors, such as:

  • Living in tropical regions
  • Traveling to or visiting specific countries where malaria has been reported

Regions affected by malaria include:

  • Africa
  • South America
  • Central America
  • Haiti
  • Dominican Republic
  • Islands in the Pacific
  • Some parts of Asia
  • Some parts of Middle East

Due to this, people traveling to these regions are advised to seek necessary precautions prior to their trip, and to seek emergency medical care if they experience the symptoms of malaria even a year after getting back from their trip. Despite the fact that malaria thrives only in tropical areas, thousands of people were diagnosed with the disease even in countries with temperate climate, such as the UK, particularly due to recent travels to affected areas.

There are many ways to avoid becoming infected with the disease even when traveling to affected countries. These include:

  • Wearing clothing that covers the arms and legs to protect oneself from mosquito bites
  • Applying insect repellents on exposed areas of the body
  • Using insecticide-treated mosquito nets while sleeping
  • Taking a complete course of antimalarial tablets exactly as instructed by the prescribing physician. Doctors can prescribe malaria prevention tablets during a pre-travel consultation.

Key Symptoms

The main symptoms of malaria include:

  • High fever
  • Headache
  • Vomiting
  • Diarrhea
  • Muscle pain
  • Nausea
  • Convulsions
  • Bloody stools
  • Sweating profusely
  • Moderate to severe chills
  • Drop in blood sugar

As some of these are also symptoms of a cold and other types of less serious infections, it is important to observe the symptoms and seek medical attention if they seem to be getting worse. Also, it is important to consider the risk factors involved, such as if the patient has been on a recent trip to a tropical region, to determine whether it is time to go to the doctor.

Unless the condition is promptly diagnosed and treated, the patient faces risk of developing more serious complications, such as:

  • Cerebral malaria – This is characterized by blockages in the small blood vessels that deliver blood to the brain. Unless prevented on time, this can cause seizures, permanent brain damage, or even a coma.

  • Severe anemia – The infection may render the red blood cells unable to deliver enough oxygen to the entire body. The lack of oxygen may cause weakness, drowsiness, or fainting.

  • Congenital malaria – This occurs when a pregnant woman becomes infected and passes the disease on to her baby.

  • Pulmonary edema – This occurs when fluid builds up in the lungs and causes breathing difficulties.

  • Organ failure – This occurs when the parasites cause major damage to the patient’s vital organs, such as the kidneys and liver.

Malaria is also more threatening when it affects babies, young children, pregnant women, and the elderly. Thus, individuals who fall into these categories are usually advised against traveling to high-risk areas.

Diagnosis of the disease can be done using a simple blood test, and the results are usually received the same day. Thus, treatment can be started right away.

Who to See and Types of Treatments Available

If a person is exhibiting symptoms of malaria and has been on a recent trip to high-risk areas, he or she should be brought to the emergency room or to a general physician or family doctor, who can request for a blood test to diagnose the problem. As mentioned earlier, it is important to seek medical care right away as the disease can progress very quickly. However, when caught and treated early, it can be easily treated and the patient is highly likely to make a complete recovery.

The primary treatment for the disease involves the same antimalarial tablets that are prescribed as a precautionary measure. The dosage and the period of medication will be decided based on the following factors:

  • The specific type of infection involved
  • The severity of symptoms
  • If complications have arisen
  • The place of infection
  • Medical history
  • Previous usage of an antimalarial medication
  • Existing health condition, such as an ongoing pregnancy

A person who has used a specific antimalarial tablet in the past may need to use a different type as Plasmodia parasites can develop immunity to the common medications that are currently in use.

As of now, a vaccine to prevent malaria is not yet available, but is actively being developed by scientists all over the world.


  • Fairhurst RM, Wellems TE. Malaria (plasmodium species). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 276.

  • Patel SS. Malaria. In: Auerbach PS. Wilderness Medicine. 6th ed. Philadelphia, PA: Elsevier Mosby; 2012:chap 49.

Share This Information: