What is malaria?

Learn how the disease is transmitted, what the symptoms are, how to treat it — and how to prevent malaria in the first place.
mosquito bites
Even though there is a chance malaria could be a life-threatening disease, most people do recover.Getty Images
By Madeline Merinuk

Malaria is a disease that’s transmitted by mosquitoes. It is treatable (and preventable), but in severe cases malaria can be deadly. While it may not seem like much of a threat to Americans, about 2,000 cases get diagnosed in the U.S. annually, according to the CDC, though the majority of these cases are contracted during people's travels outside the States.

What are the causes of malaria?

People typically get malaria from a mosquito bite. Mosquitoes can become infected with several different malaria parasites from the Plasmodium genus that can be transmitted to humans. If bitten by one of these mosquitoes, the parasite will release into your bloodstream, which will then cause symptoms of malaria.

Dr. Chistopher Plowe, the director of the Duke Global Health Institute, told TODAY that the most common transmission is via mosquito bite, but there are some very rare circumstances in which malaria could be transmitted in other ways, such as through the shared use of syringes, or through organ transplants or blood transfusions. The CDC also notes that it's possible for malaria to be transmitted from mother to infant before or during birth. Plowe said that other than these rare exceptions, malaria is cannot be transmitted from person to person.

What are the symptoms of malaria?

According to the CDC, symptoms of malaria tend to start appearing within 10 days to four weeks after being infected. Rarely will symptoms show months after infection, but it is possible in some cases. Symptoms of malaria typically include:

  • Shivering
  • Chills
  • High fever
  • Profuse sweating
  • Headache
  • General malaise
  • Nausea
  • Vomiting
  • Abdominal pain
  • Diarrhea
  • Muscle pain

Malaria can also cause anemia, jaundice, seizures and mental confusion. In severe cases, it can present some life-threatening complications. For example, the blood vessels in your brain could swell, or malaria could lead to organ failure in your kidneys, liver or spleen, according to the CDC.

Plowe told TODAY he has personally contracted malaria four times while working in Africa, so he can personally speak to experiencing the symptoms. He emphasized that for the most part, people in the U.S. who have malaria contracted it abroad, and brought it back to the U.S. with them. “Virtually all U.S. cases are returning travelers,” he said.

How is malaria treated?

Your doctor should be able to diagnose you with malaria from a physical exam and will likely ask you about any recent travels. If you have an enlarged spleen or liver, and the doctor detects symptoms of malaria, you'll likely be sent to get bloodwork done to confirm the diagnosis.

If diagnosed, Plowe said doctors can prescribe certain medicines based on the severity of your diagnosis, and most cases are effectively treated that way. “Most people recover pretty quickly,” he said.

Some of these parasites have a resistance to drugs, which could prompt your doctor to prescribe multiple medications, or even admit you to the hospital to have your airways regulated, or to get a blood transfusion if necessary, said Plowe.

Even though there is a chance malaria could be a life-threatening disease, most people do recover — as long as there are no complications that arise while infected.

How is malaria prevented?

If you travel to a place where you'll be at risk of contracting malaria, Plowe said the most effective way to prevent getting infected is to get a prescription for anti-malarial medication from your doctor before you leave and take it as directed. “There’s a lot of misinformation on the Internet about the side effects of malaria pills… of course every pill has side effects, but everyone should be able to tolerate at least one variation of an anti-malarial drug,” said Plowe.

If traveling to a subtropical climate, you can reduce your exposure to mosquitoes by wearing long pants and long-sleeved shirts or sleeping with a bed net, if possible.

Is there a vaccination for malaria?

There is no licensed vaccine for malaria in the U.S., according to Plowe, although there is an approved one in Europe. “It doesn’t work very well, but it’s better than nothing,” said Plowe. He says the WHO is still working to create a vaccination that works and is cost-effective in Africa, where the virus is more prevalent.