LIFE CYCLES OF MALARIAL ORGANISM IN MOSQUITO (ANOPHELES) AND MAN 



IN THE LIVER, 1st 

 Exoerythrocyti 



1 Sporozoite enters blood 



2 Sporozoite enters liver eel 

 3,4 Asexual cycle 

 5,6.7 Second asexual cycle 



THE MOSQUITO 

 Stomach 



etocytes (sex cells) 



re cells 



izotion 



individuol (zygote) 



n Woll of Stomach 



Ookinete forms oocyst 

 , 18 Division into 

 sporozoites 



19 Sporozoites freed 



20 Sporozoites enter 

 salivary glands 

 escape mto blood 

 Mitti saliva 



N HUMAN BODY 



BLOOD 

 CAPILLARIES 



8 

 9 

 10 

 II 



12 



THE BLOOD STREAM, 7th DAY ON 



Erythrocytic stages (in red cells) 



Ring stage 



Ameboid stage 



Schizonf stage 



Merozoites escaping from blood cells 



Gametocytes form (sexuol phase) 3rd week 



Fig. 21.15. Life history of the parasite, Plasmodium vivax, which causes benign 

 tertian malaria. In the human body. An infected female Anopheles mosquito bites 

 and injects saliva containing the parasites into the blood of its victim. Stages 1,2; 

 the parasites travel in the blood and enter the liver cells. Stages 3-7; the parasites 

 multiply in the liver cells. Stages 8-12; the parasites leave the liver, enter the blood; 

 many but not all invade the red blood cells, multiply and the red cells burst; 

 gametocytes (sexual phase) develop in some of the red blood cells. In the mosquito. 

 A female mosquito of the genus Anopheles bites and sucks blood from a person 

 whose blood contains developing gametocytes of Plasmodium vivax. Stages 12-15; 

 in the stomach the male and female cells mature, fertilization occurs and young 

 parasites develop. Stages 16-20; phases of growth and multiplication occur in the 

 wall of the stomach, followed by release, migration and entrance into the salivary 

 glands. The parasites are now ready for distribution into any individual whom the 

 mosquito may bite. 



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