Human malaria is caused by 4 species of protozoal parasites of the genus Plasmodium, ie. P.falciparum, P.vivax, P.malariae and P.ovale. The most prevalent species found in Thailand are P.falciparum and P.vivax. Falciparum malaria is the most dangerous form of the disease and can be fatal. Vivax and ovale malaria often remain quiescent in the liver and, at times, are released into the bloodstream and cause recurrence of the disease. |
| |
|
 Endemic areas |
| |
The endemic areas of malaria in Thailand are along the border provinces, especially in the hilly and forested areas where there are breeding places of anopheline mosquitoes, the vectors of malaria.
Provinces where malaria incidence is highest are Mae Hong Son, Tak, Trat, Ranong, Kanchanaburi, Chanthaburi, Sa Kaeo, Prachuap Khiri Khan, Ratchaburi and Chumphon.
|
| |
|
| Transmission |
| |
Malaria is transmitted to humans through the bite of infected female Anopheles mosquitos. |
| |
|
| Life cycle |
| |
| |
|
| |
|
| |
1. Malaria parasites in the outer wall of the mosquito's stomach.
2. Infective stage of malaria parasites in the salivary glands of a mosquito vector.
3. Malaria parasites (hypnozoites) in the human liver.
4. Hypnozoites are released into the bloodstream.
5. Sexual stages of malaria parasites. |
| |
|
| Symptoms |
| |
Usual presenting symptoms occurred 10-14 days after mosquito's bite is fever accompanied by headache, muscle pain, nausea, vomiting and anorexia. The classical symptoms of the disease, which the name paludism is derived from, are rigor, high fever, followed by sweating; these symptoms occur only in some cases. |
| |
|
| Diagnosis |
| |
By blood examination for malaria parasites. |
| |
|
| |
|
| |
|
| Treatment |
| |
Malaria is curable if the patient receives an accurate diagnosis and prompt treatment. However, severe infections or drug resistance may occur and lead to death.
The patient should not treat him/herself but medical consultation is recommended.
|
| |
|
| Prevention |
| |
The preventive measure for those who have to enter malaria endemic areas, is to prevent themselves from being bitten by a mosquito vector, eg. |
| |
- put on clothes to cover the entire body, preferably light color
- apply mosquito repellent to the exposed area of the body
- sleep in a bed-net; an impregnated bed-net provided more efficacy in control
- a screened bedroom should be sprayed with an insecticide before use
|
| |
In Thailand, chemoprophylaxis is not recommended due to drug resistance, and side-effects may also occur. If someone has any of the above symptoms and suspects of malaria, they should seek urgent medical advice. |
Facebook