Cerebral malaria is a serious neurological complication of severe malaria that affects about 1% of children under the age of 5 who have been infected with Plasmodium falciparum.
An overview of malaria
The Plasmodium genus of unicellular protozoan parasites are responsible for causing the disease malaria in humans, the most deadly of which includes Plasmodium falciparum. Each year, malaria affects about 219 million people, with about 500,000 people dying each year from this disease. It is estimated that about 93% of the people who die from malaria reside in sub-Saharan Africa, many of whom are under the age of 5.
Humans typically acquire malaria after being bitten by an infected female mosquito of the Anopheles genus. In addition, blood-borne transmission through the transfusion of blood products, transplantation, or needle-sharing, as well as congenital transmission of malaria can also occur. Once infected, malaria can either evolve into simple or severe forms, the latter of which is a less frequent presentation of this disease.
Severity of malaria
The severity of malaria is often dependent upon the immune status of the host, as well as the area in which malaria has been acquired. For example, areas that have a stable endemic of P. falciparum will often find that severe malaria commonly occurs in children up to 5 years of age, whereas older children and adults will experience less severe forms of the infection due to partial immunity. Comparatively, areas with lower endemic rates will have a less defined age distribution of severe malaria.
Initially, malaria will cause nonspecific flu-like symptoms including malaise, anorexia, lassitude, dizziness, headache, body aches, nausea, vomiting, and chills. The progression of malaria into more severe symptoms will often depend upon the infecting parasite. For example, infection by P. vivax and P. ovale will typically cause a classical malaria paroxysm that includes three symptom stages, beginning with a cold stage, followed by a hot stage, and ending with a sweating stage.
Most of the severe complications of malaria will occur in individuals who have been infected with P. falciparum. Severe malaria is often defined as the presence of Plasmodium in peripheral blood. Some of the complications of severe malaria can involve the central nervous system, which is otherwise referred to as cerebral malaria, the pulmonary system, renal system, and/or the hematopoietic system. The progression to these complications is often rapid and can lead to death in many cases.