MALARIA

 

by dr. Darwin Manurung

What is malaria?

Malaria is a serious and sometimes fatal disease caused by a parasite that commonly infects a certain type of mosquito which feeds on humans. People who get malaria are typically very sick with high fevers, shaking chills, and flu-like illness. Four kinds of malaria parasites infect humans: Plasmodium falciparum, P. vivax, P. ovale, and P. malariae. In addition, P. knowlesi, a type of malaria that naturally infects macaques in Southeast Asia, also infects humans, causing malaria that is transmitted from animal to human (“zoonotic” malaria). P. falciparum is the type of malaria that is most likely to result in severe infections and if not promptly treated, may lead to death. Although malaria can be a deadly disease, illness and death from malaria can usually be prevented.

About 1,700 cases of malaria are diagnosed in the United States each year. The vast majority of cases in the United States are in travelers and immigrants returning from parts of the world where malaria transmission occurs, including sub-Saharan Africa and South Asia.

Globally, the World Health Organization estimates that in 2016, 216 million clinical cases of malaria occurred, and 445,000 people died of malaria, most of them children in Africa. Because malaria causes so much illness and death, the disease is a great drain on many national economies. Since many countries with malaria are already among the poorer nations, the disease maintains a vicious cycle of disease and poverty.

What cause malaria?

Malaria can occur if a mosquito infected with the Plasmodium parasite bites you. There are four kinds of malaria parasites that can infect humans: Plasmodium vivaxP. ovaleP. malariae, and P. falciparum. P. falciparum causes a more severe form of the disease and those who contract this form of malaria have a higher risk of death. An infected mother can also pass the disease to her baby at birth. This is known as congenital malaria.

How is malaria transmitted?

Usually, people get malaria by being bitten by an infective female Anopheles mosquito. Only Anopheles mosquitoes can transmit malaria and they must have been infected through a previous blood meal taken from an infected person. When a mosquito bites an infected person, a small amount of blood is taken in which contains microscopic malaria parasites. About 1 week later, when the mosquito takes its next blood meal, these parasites mix with the mosquito’s saliva and are injected into the person being bitten.

Because the malaria parasite is found in red blood cells of an infected person, malaria can also be transmitted through blood transfusion, organ transplant, or the shared use of needles or syringes contaminated with blood. Malaria may also be transmitted from a mother to her unborn infant before or during delivery (“congenital” malaria). Malaria is not spread from person to person like a cold or the flu, and it cannot be sexually transmitted. You cannot get malaria from casual contact with malaria-infected people, such as sitting next to someone who has malaria.

What are the symptoms of malaria?

The symptoms of malaria typically develop within 10 days to 4 weeks following the infection. In some cases, symptoms may not develop for several months. Some malarial parasites can enter the body but will be dormant for long periods of time.

Common symptoms of malaria include:

 

How is malaria diagnosed?

Your doctor will be able to diagnose malaria. During your appointment, your doctor will review your health history, including any recent travel to tropical climates. A physical exam will also be performed.

Your doctor will be able to determine if you have an enlarged spleen or liver. If you have symptoms of malaria, your doctor may order additional blood tests to confirm your diagnosis.

These tests will show:

  • whether you have malaria
  • what type of malaria you have
  • if your infection is caused by a parasite that’s resistant to certain types of drugs
  • if the disease has caused anemia
  • if the disease has affected your vital organs

Malaria can cause a number of life-threatening complications. The following may occur:

  • swelling of the blood vessels of the brain, or cerebral malaria
  • an accumulation of fluid in the lungs that causes breathing problems, or pulmonary edema
  • organ failure of the kidneysliver, or spleen
  • anemia due to the destruction of red blood cells
  • low blood sugar

How malaria is malaria treated?

Malaria can be a life-threatening condition, especially if you’re infected with the parasite P. falciparum. Treatment for the disease is typically provided in a hospital. Your doctor will prescribe medications based on the type of parasite that you have.

In some instances, the medication prescribed may not clear the infection because of parasite resistance to drugs. If this occurs, your doctor may need to use more than one medication or change medications altogether to treat your condition.

Additionally, certain types of malaria parasites, such as P. vivax and P. ovale, have liver stages where the parasite can live in your body for an extended period of time and reactivate at a later date causing a relapse of the infection.

If you’re found to have one of these types of malaria parasites, you’ll be given a second medication to prevent a relapse in the future.

What’s the long-term outlook for people with malaria?

People with malaria who receive treatment typically have a good long-term outlook. If complications arise as a result of malaria, the outlook may not be as good. Cerebral malaria, which causes swelling of the blood vessels of the brain, can result in brain damage. The long-term outlook for patients with drug-resistant parasites may also be poor. In these patients, malaria may recur. This may cause other complications.

Tips to prevent malaria

There’s no vaccine available to prevent malaria. Talk to your doctor if you’re traveling to an area where malaria is common or if you live in such an area. You may be prescribed medications to prevent the disease.

These medications are the same as those used to treat the disease and should be taken before, during, and after your trip. Talk to your doctor about long-term prevention if you live in an area where malaria is common. Sleeping under a mosquito net may help prevent being bitten by an infected mosquito. Covering your skin or using bug sprays containing DEET may also help prevent infection.

If you’re unsure if malaria is prevalent in your area, the CDC has an up-to-date map of where malaria can be found.