Malaria is a life-threatening mosquito-borne blood disease caused by a Plasmodium parasite. It is transmitted to humans through the bite of the female Anopheles mosquito. Once an infected mosquito bites a human, the parasites multiply in the host's liver before infecting and destroying red blood cells.
Uncomplicated malaria - This is diagnosed when symptoms are present, but there are no signs to indicate severe infection or dysfunction of the vital organs. This form can become severe malaria if left untreated, or if the host has poor or no immunity. Symptoms of uncomplicated malaria typically last 6 to 10 hours and recur every second day. Some strains of the parasite can have a longer cycle or cause mixed symptoms. As symptoms resemble those of flu, they may be undiagnosed or misdiagnosed in areas where malaria is less common.
In uncomplicated malaria, symptoms progress as follows, through cold, hot, and sweating stages, a sensation of cold with shivering, fever, headaches, and vomiting, seizures sometimes occur in younger people with the disease, sweats, followed by a return to normal temperature, with tiredness. In areas where malaria is common, many patients recognize the symptoms as malaria and treat themselves without visiting a doctor.
Severe malaria - In severe malaria, clinical or laboratory evidence shows signs of vital organ dysfunction. Symptoms of severe malaria include, fever and chills, impaired consciousness, prostration, or adopting a prone position, multiple convulsions, deep breathing and respiratory distress, abnormal bleeding and signs of anemia, clinical jaundice and evidence of vital organ dysfunction, Severe malaria can be fatal without treatment.
Causes - Malaria happens when a bite from the female Anopheles mosquito infects the body with Plasmodium. Only the Anopheles mosquito can transmit malaria. When an infected mosquito bites a human host, the parasite enters the bloodstream and lays dormant within the liver. The host will have no symptoms for an average of 10.5 days, but the malaria parasite will begin multiplying during this time. The new malaria parasites are then released back into the bloodstream, where they infect red blood cells and multiply further. Some malaria parasites remain in the liver and are not released until later, resulting in recurrence. An unaffected mosquito becomes infected once it feeds on an infected individual. This restarts the cycle.
Treatment and prevention - Treatment aims to eliminate the Plasmodium parasite from the patient's bloodstream. Those without symptoms may be treated for infection to reduce the risk of disease transmission in the surrounding population.