Exoerythrocytic development of Plasmodium gallinaceum in the White Leghorn chicken

Abstract

Plasmodium gallinaceum typically causes sub-clinical disease with low mortality in its primary host, the Indian jungle fowl Gallus sonnerati. Domestic chickens of European origin, however, are highly susceptible to this avian malaria parasite. Here we describe the development of P. gallinaceum in young White Leghorn chicks with emphasis on the primary exoerythrocytic phase of the infection. Using various regimens for infection, we found that P. gallinaceum induced a transient primary exoerythrocytic infection followed by a fulminant lethal erythrocytic phase. Prerequisite for the appearance of secondary exoerythrocytic stages was the development of a certain level of parasitemia. Once established, secondary exoerythrocytic stages could be propagated from bird to bird for several generations without causing fatalities. Infected brains contained large secondary exoerythrocytic stages in capillary endothelia, while in the liver primary and secondary erythrocytic stages developed primarily in Kupffer cells and remained smaller. At later stages, livers exhibited focal hepatocyte necrosis, Kupffer cell hyperplasia, stellate cell proliferation, inflammatory cell infiltration and granuloma formation. Because P. gallinaceum selectively infected Kupffer cells in the liver and caused a histopathology strikingly similar to mammalian species, this avian Plasmodium species represents an evolutionarily closely related model for studies on the hepatic phase of mammalian malaria.

The Efficacy of Artesunate, Chloroquine, Doxycycline, Primaquine and a Combination of Artesunate and Primaquine against Avian Malaria in Broilers

“…This high mortality rate has been recorded in many previous reports [2, 15]. The IUC group revealed the highest number of schizonts in the liver, spleen, kidneys and brain that accorded with the higher mortality rate in this group.…”

Exo-erythrocytic development of avian malaria and related haemosporidian parasites

“…Both the localization and the sequence of appearance of cryptozoites, metacryptozoites and phanerozoites in different organs and tissues varies markedly depending on mode of infection, parasite species, parasite strain characteristics, age of birds, intensity of infection, stage of infection, and some other factors [4, 10, 53–55, 61, 73, 91, 92, 114, 115, 128]. …”

“…Brain damage leading to ischaemic changes is among the most severe pathologies caused by the human malaria parasite Plasmodium falciparum and many species of avian malaria, but the mechanisms of pathology during human falciparum malaria and bird malaria are different [4, 10, 12, 53, 94, 136, 137]. Both in birds and humans, cerebral malaria is due to interruption of the circulation in brain vessels (Fig.…”

Looking under the skin: the first steps in malarial infection and immunity

“…Nonetheless, the development of avian Plasmodium spp. in the skin 75 , the similarity between host cell invasion by P. yoelii and P. falciparum sporozoites 76 , and an early description of Plasmodium vivax in a human lymph node 77 all point to the possibility that a skin-draining lymph node component in the PE phase of the Plasmodium spp. life cycle is more conserved than previously appreciated.…”