Preventive medicine for the tropics by Lucas and
Culles (2009) states that the life cycle of the malaria parasite is in two
phases which are “the period of development in the mosquito and the period of
infection in man”.
Culles (2009) states that the life cycle of the malaria parasite is in two
phases which are “the period of development in the mosquito and the period of
infection in man”.
When the mosquito ingest the infected blood a
period of development of plasmodium occur in the body of the mosquito. This
development period is usually between 10 – 14days.
period of development of plasmodium occur in the body of the mosquito. This
development period is usually between 10 – 14days.
During this period, there is the production of
sporozoites which are stored in the saliva of the mosquito. At these stages,
the sporozoites are ready for transmission into their victim.
sporozoites which are stored in the saliva of the mosquito. At these stages,
the sporozoites are ready for transmission into their victim.
When this infected mosquito bites man, it
introduces this sporozoites into the blood stream. The sporozoites stays in the
blood stream for about 30 minutes or less before invading tissues of the body
preferably the liver cells.
introduces this sporozoites into the blood stream. The sporozoites stays in the
blood stream for about 30 minutes or less before invading tissues of the body
preferably the liver cells.
Ajayi (2002) stressed that depending on the type of
malaria parasites that is plasmodium vivax. Plasmodium malariae or plasmodium
falciparum. The incubation in the liver varies from 12 – 16 days. The infected
liver cells then ruptures and the malaria parasite which develops in the
parachymal cell of the liver are liberated some of them penetrate the red blood
cell while others enter other liver cell further. In preventive medicine for
the tropics by lucas and cilies, the authors are of the opinion that the
sporozoites in the parachymal cells of the liver develop to form menozoites
which are liberated from the liver cells in the blood stream.
malaria parasites that is plasmodium vivax. Plasmodium malariae or plasmodium
falciparum. The incubation in the liver varies from 12 – 16 days. The infected
liver cells then ruptures and the malaria parasite which develops in the
parachymal cell of the liver are liberated some of them penetrate the red blood
cell while others enter other liver cell further. In preventive medicine for
the tropics by lucas and cilies, the authors are of the opinion that the
sporozoites in the parachymal cells of the liver develop to form menozoites
which are liberated from the liver cells in the blood stream.
The period of development in the liver cells is
called the pre-erythrocytic phase while the release of the merozoites into the
blood stream start another phase called erythrocytic phase. The merazoites
develop into a ringa shape called trophozoites in the red blood cells. This
trophozoites mature to form schizont containing merozoites. Many of them
re-infect other red blood cells to form erythrocytic schizogony.
called the pre-erythrocytic phase while the release of the merozoites into the
blood stream start another phase called erythrocytic phase. The merazoites
develop into a ringa shape called trophozoites in the red blood cells. This
trophozoites mature to form schizont containing merozoites. Many of them
re-infect other red blood cells to form erythrocytic schizogony.
A response do unknown stimulus cause a number of
the released merozoites after erythrocytic schizogony to form male and female
gametocyst. In this form which believed to be inserted in man which provides
the reservoir of infection and makes the mosquito cycle to continue while they
remain in the red blood cells for the period of their survival which is usually
120 days.
the released merozoites after erythrocytic schizogony to form male and female
gametocyst. In this form which believed to be inserted in man which provides
the reservoir of infection and makes the mosquito cycle to continue while they
remain in the red blood cells for the period of their survival which is usually
120 days.
Some of the merozoites liberated from the liver do
not enter into the blood stream but re-infect the liver to continue the
pre-erythrocytic cycle and this type of merozoites are responsible for the
exo-erythrocytic cycle. The eventual discharge of the merozoites from the
exo-erythrocytic form into the blood results in re-invasion of the red blood
cells so producing a relapse in an affected patient.
not enter into the blood stream but re-infect the liver to continue the
pre-erythrocytic cycle and this type of merozoites are responsible for the
exo-erythrocytic cycle. The eventual discharge of the merozoites from the
exo-erythrocytic form into the blood results in re-invasion of the red blood
cells so producing a relapse in an affected patient.
This exo-erythrocytic form occurs in plasmodium
vivax, plasmodium ovale and plasmodium malariae but in plasmodium falciparum,
the exo-erythrocytic form do not persist, this follows therefore that when the
erythrocytic phase is adequately treated, no relapse occur.
vivax, plasmodium ovale and plasmodium malariae but in plasmodium falciparum,
the exo-erythrocytic form do not persist, this follows therefore that when the
erythrocytic phase is adequately treated, no relapse occur.
Therefore it is very rare for relapse to occur
after one year of freedom from exposure to malaria infection.
after one year of freedom from exposure to malaria infection.