It is an intracellular protozoan parasite. It is also a digenetic parasite i.e. it needs two hosts for completion of lifecycle one is human and the other is female anopheles mosquito. Female anopheles mosquito also acts as a vector ( an insect which transmits causative agent from one person to another). Only 4 species of Plasmodium are infective to man which causes malaria.
P.vivax → BenginTertian Malaria
P. falciparum → Malignant Tertian Malaria
P. malaria → Quartan Malaria
P. ovale → Mild Tertian Malaria
Plasmodium falciparum is the most dangerous species. It cause cerebral malaria and black water fever.
Phylum : Protozoa
Class : Sporozoa
Genus : Plasmodium
Species : Vivax
Common name : Malarial parasite
In Nepal, it is common in terai region. 10 districts of the hilly region are reported as malaria free district.
It mostly occurs in two different morphological stages:
|It is a fully grown feeding stage of plasmodium.||It is a non-infecting stage of plasmodium.|
|It is formed in human RBC.||It is formed in salivary glands of mosquito.|
|It is in rounded or amoeboid shape.||It is in sickle- shaped.|
|Nucleus is eccentric.||Nucleus is present in the centre.|
|The body is covered with plasmalemma.||Body is covered with the pellicle.|
|It is non- motile.||It is motile.|
|Food vacuole contains toxic haemozoin pigment.||Food vacuole contains apical cap and secretory glands for penetration of the host cell.|
It is the period between initial infection of sporozoites and appearance of the first symtom. It is of 14 days in P.vivax.
The rise of malarial fever at the interval of every 48 hours is called paroxysm. Such fever is also called intermittent or relapsing fever.
It is the reoccurrence of malarial symptoms after the certain time period of treatment. It is caused by crypto merozoites of the previous infection as they are unaffected by anti-malarial drugs.