Is an acute and sometimes chronic infectious disease characterized by cycles of chills, fever, prostration and sweating, caused by the parasitic infection of red blood cells by a protozoan which is transmitted by the bite of an infected female mosquito and rarely via blood transfusion.

Malaria is caused by protozoan parasites of the genus Plasmodium. Four species of Plasmodium can produce the disease in its various forms:

Plasmodium falciparum Plasmodium vivax Plasmodium ovale Plasmodium malaria

P. falciparum is the most widespread and dangerous of the four: untreated it can lead to fatal cerebral malaria. Malaria parasites are transmitted from one person to another by the female anopheline mosquito. The males do not transmit the disease as they feed only on plant juices. There are about 380 species of anopheline mosquito, but only 60 or so are able to transmit the parasite. Like all other mosquitoes, the anophelines breed in water, each species having its preferred breeding grounds, feeding patterns and resting place. Their sensitivity to insecticides is also highly variable. Plasmodium develops in the gut of the mosquito and is passed on in the saliva of an infected insect each time it takes a new Blood meal. The parasites are then carried by the Blood in the victim's Liver where they invade the cells and multiply.The parasite spends most of its life in the red Blood cells of humans. Female mosquitoes transmit the parasites by first ingesting them when feeding on an infected person's Blood and then injecting them when biting another person. On entering a human, the parasite invades a Liver Cell, takes on a new form and makes copies of itself. Eventually, the Liver Cell ruptures and releases the parasites to the bloodstream where they infect red Blood cells. Within the Blood cells, most parasites reproduce again, which kills the cells and the parasites then invade more Blood cells. Other parasites, while in the Blood cells, develop into male and female forms. When these cells are sucked up by a mosquito, the cells burst, freeing the sexual forms of the paraSsite. Within the mosquito, the two forms merge to create an oocyst. After maturing, the oocyst ruptures to release thousands of parasites, which migrate to the mosquito's Salivary glands, awaiting her next bite.

The general symptoms include Headache, nausea, fever, Vomiting and flu-like symptoms, although these symptoms may differ depending on the type of plasmodium that caused the infection Malaria causes a flu-like illness and these would include:

Fever rigors headaches sweating tiredness myalgia (limbs and back) abdominal pain diarrhoea loss of appetite orthostatic Hypotension Nausea slight Jaundice Cough enlarged Liver and Spleen (sometimes not palpable) vomiting

Fever in the first week of travel in a malaria-risk area is unlikely to be malaria; however, any traveller feeling ill should seek immediate medical care. Although malaria is unlikely to be the cause, any Fever should be promptly evaluated. If you or your child becomes ill with a Fever or flu-like illness while travelling in a malaria-risk area and up to 1 year after returning home, seek immediate medical care. Tell your health care provider where you have been travelling.

Malaria is difficult to diagnose under the best circumstances. Definitive diagnosis is based on the observation through a microscope of parasites in the red blood cells of a patient. Newer diagnostic tools include fluorescent staining, genetic probes and antigen detection in the form of a dip stick, but these methods are not widely used. The most important step of diagnosis is to recognize the symptoms of malaria, so the patient can receive treatment.

The normal treatments for malaria infection are drugs based on quinine, or a combination drug therapy known as ACTs, based on artemisinin (which is expensive).

Local cost and availability of antimalarial drugs. Area of malaria acquisition (i.e. drug resistance pattern of P. falciparum). Prior chemoprophylaxis. Known allergies. Concomitant illnesses other than malaria. Age and pregnancy. Likely patient compliance with therapy. Risk of re-exposure to malaria after treatment

P.falciparum: This species was originally sensitive to chloroquine. However, strains resistant to this and other antimalarial drugs are now commonplace. Because the parasite is able to multiply very rapidly and sequester within the microvasculature, a life threatening illness may develop in a very short space of time. Uncomplicated malaria (where patients can take oral therapy) can usually be treated effectively with one of three regimens: The treatment of malaria normally calls for admission to hospital, because it may be malignant malaria, which can have a fatal outcome in only a few days. In addition, there is an increasing level of resistance of the malaria parasite, particularly P. falciparum, to several of the known antimalarial products. The same antimalarial agents may be used to treat malaria as to prevent it, but if you have caught malaria in spite of using the correct preventive medication, a different product should be used to combat the possibility of resistant parasites. Severe malaria (where patients have Coma, Jaundice, renal failure, hypoglycaemia, lactic acidosis, severe anaemia, high parasite count, hyperpyrexia) is ideally treated in an intensive care or high dependency unit where patients can be monitored closely both clinically and biochemically. Intravenous quinine is the treatment of choice but rapid injection can lead to Hypotension, dysrhythmias and death. P. malariae, P. ovale. : Treatment for the eradication of these two strains of malaria is the same as that for P. vivax except it is not necessary to give primaquine to those patients with P. malariae. P.vivax: Most strains of P. vivax are still sensitive to chloroquine, although some chloroquine resistant strains have been reported This drug will clear the erythrocyte stages of the parasite but it has no effect on the exo-erythrocytic Liver stage and a course of primaquine (an 8-amino-quinoline) is required for radical cure.

The best way to prevent malaria is to avoid being bitten by a mosquito, since the disease is transmitted by the bite of the malaria. Apart taking measures to prevent being bitten in the first place, antimalarial drugs must also be taken before entering a high risk area. The time that you are most susceptible to be bitten is between dusk and dawn - outdoors and inside, but some preventative measures can be used to avoid the bite of the mosquito. Various ways can be followed to reduce the risk of being bitten, but following all available recommendations will help reduce the risk.

Wearing protective clothing Using proprietary insect repellent Sleeping under a mosquito net Fixing your house / room to be mosquito "un-friendly"

Once the diagnosis of malaria has been made on the basis of a positive blood smear or strong clinical suspicion, then treatment should be started without delay. Chloroquine remains the mainstay in the treatment of malaria. The other drugs that are often used include Mefloquine, Tetracyclines, Primaquine, Pyrimethamine, Proguanil and Quinine. Newer drugs like Halofantrine, Artesunate and Qinghaosu are being used for cases of Chloroquine-resistant malaria. Except for the Falciparum malaria, patients who receive adequate treatment for the other forms, most often have an uneventful recovery. However, resistance to the conventional drugs is increasing and is a major cause for worry. Cerebral malaria is a medical emergency and even with the best of treatment there is a substantial mortality rate.

Cerebral malaria Death Mother-infant transmission - pregnant mother can infect the foetus. Low birth weight (see Pregnancy symptoms) Anaemia Jaundice Kidney failure Fluid imbalance Enlarged Spleen Enlarged Liver Blackwater Fever Hematuria Liver complications Brain complications

Malaria can cause anaemia and Jaundice, and can lead to Coma, renal failure, acute Respiratory distress, and death.