Malaria is a serious and sometimes fatal disease caused by a group of malaria parasites, namely Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale, Plasmodium vivax and Plasmodium knowlesi. It is commonly found in many parts of tropical and sub-tropical areas where the climate is warm, like Africa, South-East Asia and South America.
Symptoms of malaria include fever, chills, headache, muscle pain and weakness, cough, vomiting, diarrhoea and abdominal pain. Complications include anaemia, generalised convulsion, circulatory collapse, organ failure such as kidney failure, coma and death if the disease is not treated promptly.
Mode of transmission
Malaria is a vector-borne communicable disease transmitted by an infected female Anopheline mosquito. When the mosquito bites a malaria patient, the mosquito becomes infected and will pass on the disease when it bites another person. Malaria is not transmitted from person to person. However, malaria can be transmitted through contaminated blood or blood product transfusion, organ transplant, or shared needles or syringes. Malaria may also be transmitted from a mother to her foetus/newborn baby before or during delivery.
The incubation period varies with different species of Plasmodium. This usually ranges from 7 – 30 days but may be up to months or even longer after the bite of an infected Anopheline mosquito.
There are effective drugs against malaria but early diagnosis and prompt treatment are crucial. The doctor would prescribe a course of anti-malarial drugs with other supportive measures. The patient should complete the whole course of medication to ensure clearance of the malaria parasites.
General measures on preventing mosquito-borne diseases
Help prevent mosquito proliferation
Pregnant women and children of 6 months or older can use DEET-containing insect repellent. For children who travel to countries or areas where mosquito-borne diseases are endemic or epidemic and where exposure is likely, children aged 2 months or above can use DEET-containing insect repellents with a concentration of DEET up to 30%. For details about the use of insect repellents and the key points to be observed, please refer to 'Tips for using insect repellents'.
For more information about control and prevention of mosquito breeding, please visit the website of the Food and Environmental Hygiene Department (FEHD) at http://www.fehd.gov.hk/english/pestcontrol/handbook_prev_mos_breeding.html