How Malaria Spreads

What you need to know
  • Most people get malaria from the bite of an infective mosquito.
  • Most cases of malaria in the U.S. are in people who have traveled to or from areas where malaria is widespread.
  • Once infected with malaria, it can take several days or even months to feel sick.


Malaria is a disease caused by a parasite.

How it spreads

Most people get malaria when bitten by a mosquito infected with the malaria parasite. Only female Anopheles mosquitoes can spread malaria. For the Anopheles mosquito to become infected, they must bite, or take a blood meal, from a person with the malaria parasites. About one week later, the mosquito will inject the parasites via her saliva into the next person she bites. And the cycle of infection continues.

In rare occasions, malaria can spread through

  • blood transfusions,
  • organ transplant,
  • sharing needles or syringes contaminated with malaria-infected blood, or
  • congenitally, meaning from a mother to her unborn infant before or during delivery.

How it does not spread

Malaria is not contagious. People can’t spread malaria to other people like a cold or the flu. You can’t get malaria through casual contact (sitting next to a person with malaria), close physical contact, or sexual contact.

Factors that increase risk

Anyone can get malaria. Most cases occur in people who live in countries with widespread malaria. People from countries with no malaria can become infected when they travel to countries with malaria.

Plasmodium falciparum is the type of malaria that most often causes severe and life-threatening malaria. It is very common in many countries in Africa south of the Sahara Desert.

Populations most at risk

Individuals with the most risk of getting very sick and dying from malaria include

  • People who have little or no immunity to malaria. This can include young children and pregnant women or travelers coming from areas with no malaria.
  • People heavily exposed to the bites of mosquitoes infected with P. falciparum.
  • People living in rural areas who lack access to health care.

Due to these risk factors, an estimated 90% of deaths caused by malaria occur in Africa south of the Sahara Desert. And most of these deaths occur in children under 5 years of age.