Plasmodium falciparum | Plasmodium vivax | Plasmodium ovale | Plasmodium malariae | Plasmodium knowlesi[1-7] | |
Geography | Tropical, temperate zones | Tropical, temperate zones, absent from West Africa | Tropical, endemic in West Africa, present in Philippines, Indonesia, and Papua New Guinea | Tropical, isolated pockets | Southeast Asia |
RBC preference | RBCs of all ages | Young RBCs (reticulocytes) | Young RBCs (reticulocytes) | Older RBCs | RBCs of all ages |
Infected RBC diameter | Normal | Larger than normal | Larger than normal | Normal or smaller than normal | Normal |
Ameboid trophozoites | No | Yes | Yes | No | No |
Band forms | No | No | No | Yes | Yes |
Schizont* | 16 to 20 merozoites; very rare in peripheral circulation | 20 to 24 merozoites | 4 to 16 merozoites (8 typical) | 6 to 12 merozoites (8 or 10 typical) | 8 to 16 merozoites (10 typical) |
Parasitemia | Can be very high | Usually <2% | Usually <2% | Usually very low | Can be high |
Disease severity | End organ damage and death can occur | End organ damage and death less common than P. falciparum but can occur | Severe disease uncommon | Severe disease rare | Severe disease can occur |
Chloroquine resistance | Yes | Yes | No | Rare | No |
Relapses from liver | No | Yes | Yes | No | No |
Incubation period | 12 days (8 to 25) | 14 days (8 to 25; occasionally months) | 15 days (9 to 17) | 18 days (15 to 30; occasionally months to years) | 11 days (9 to 12) |
Prepatent period¶ | 11 days | 12 daysΔ | 12 days | 32 days | Uncertain in naturally infected humans |
Cycle in red cell | 48 hours | 48 hours | 48 hours | 72 hours | 24 hours |
RBC: red blood cell.
* Identification of a schizont with >12 merozoites in the peripheral circulation is an important diagnostic clue for P. vivax. In general, schizonts of P. falciparum are very rarely seen in blood films; they occur only in the setting of severe disease with hyperparasitemia.
¶ The prepatent period is the time from mosquito bite to the first appearance of parasites in the peripheral blood (as detected by microscopy).
Δ The latency period of vivax is typically longer than falciparum (refer to UpToDate table summarizing time to symptoms for each species).آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟