Malaria is a life-threatening disease. It’s typically transmitted through the bite of an infected Anopheles mosquito. Infected mosquitoes carry the Plasmodium parasite. When this mosquito bites you, the parasite is released into your bloodstream.
Once the parasites are inside your body, they travel to the liver, where they mature. After several days, the mature parasites enter the bloodstream and begin to infect red blood cells. Within 48 to 72 hours, the parasites inside the red blood cells multiply, causing the infected cells to burst open. Learn more about mosquitoes and treating mosquito bites.
The parasites continue to infect red blood cells, resulting in symptoms that occur in cycles that last two to three days at a time.
Malaria is typically found in tropical and subtropical climates where the parasites can live. The World Health Organization (WHO) estimates that about 3.2 billion people are at risk of malaria.
In the United States, the Centers for Disease Control and Prevention (CDC) report 1,700 cases of malaria annually. Most cases of malaria develop in people who travel to countries where malaria is more common.
Malaria can occur if a mosquito infected with the Plasmodium parasite bites you. An infected mother can also pass the disease to her baby at birth. This is known as congenital malaria. Malaria is transmitted by blood, so it can also be transmitted through:
- an organ transplant
- a transfusion
- use of shared needles or syringes
The symptoms of malaria typically develop within 10 days to 4 weeks following the infection. In some people, 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:
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:
Malaria can be a life-threatening condition. 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.
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.
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.