Risk factors
The greatest risk factor for developing malaria is to live in or to visit areas where the disease is common. These include the tropical and subtropical regions of:
Sub-Saharan Africa
South and Southeast Asia
Pacific Islands
Central America and northern South America
The degree of risk depends on local malaria control, seasonal changes in malaria rates and the precautions you take to prevent mosquito bites.
Risks of more-severe disease
People at increased risk of serious disease include:
Young children and infants
Older adults
Travelers coming from areas with no malaria
Pregnant women and their unborn children
In many countries with high malaria rates, the problem is worsened by lack of access to preventive measures, medical care and information.
Immunity can wane
Residents of a malaria region may be exposed to the disease enough to acquire a partial immunity, which can lessen the severity of malaria symptoms. However, this partial immunity can disappear if you move to a place where you’re no longer frequently exposed to the parasite.