Plasmodium species (continued)
YOUNG TROPHOZOITES--RING FORMS
SPECIMEN OF CHOICE: Capillary blood.
TIME OF COLLECTION: About 8 to 12 hours after the fever peak and about 8 to 12
hours intervals thereafter (midway between the fever peaks results in clearly defined
REPORT AS PLASMODIUM SPECIES: Unless 5 or more young rings per oil
immersion field without Schuffner's granules are present: this case represents P.
falciparum (thin smear only).
CHROMATIN DOT: Small; magenta-red.
CYTOPLASM: Light blue; 1 to 3 mcm in size.
HEMOZOIN PIGMENT: Usually absent.
INFECTED ERYTHROCYTE: May be macrocytic and pale with Schuffner's granules in
cases of P. vivax and P. ovale.
See Figures 1-1, 2-1, and 4-1 in Appendix C for additional illustrations.
Figure 2-19. Ring forms of Plasmodia.