Malaria: Origin of the Term “Hypnozoite”

@article{Markus2011MalariaOO,
  title={Malaria: Origin of the Term “Hypnozoite”},
  author={Miles B. Markus},
  journal={Journal of the History of Biology},
  year={2011},
  volume={44},
  pages={781-786}
}
  • M. Markus
  • Published 2011
  • Biology, Medicine
  • Journal of the History of Biology
The term “hypnozoite” is derived from the Greek words hypnos (sleep) and zoon (animal). Hypnozoites are dormant forms in the life cycles of certain parasitic protozoa that belong to the Phylum Apicomplexa (Sporozoa) and are best known for their probable association with latency and relapse in human malarial infections caused by Plasmodium ovale and P. vivax. Consequently, the hypnozoite is of great biological and medical significance. This, in turn, makes the origin of the name “hypnozoite” a… 
The hypnozoite concept, with particular reference to malaria
  • M. Markus
  • Biology, Medicine
    Parasitology Research
  • 2010
TLDR
This paper is based on a presentation by the author, as a Life Member of the American Society of Tropical Medicine and Hygiene, to its 59th Annual Meeting in Atlanta, Georgia, USA, 3–7 November 2010, and explains how the name “hypnozoite” is applicable to a latent stage in the life cycle of Plasmodium but to some apparently dormant forms of other kinds of apicomplexan parasites as well.
Biological concepts in recurrent Plasmodium vivax malaria
TLDR
It is argued that the authors need to take into account the possibility of a dual or multiple extra-vascular origin of P. vivax non-reinfection recurrences, not arbitrarily discount it, and the existence of a P.vivax reservoir(s) is a topical subject and one of practical importance for malaria eradication.
Do hypnozoites cause relapse in malaria?
  • M. Markus
  • Biology, Medicine
    Trends in parasitology
  • 2015
TLDR
The hypnozoite theory of relapse needs to be re-evaluated in view of the recent, increased focus on P. vivax and liver stages of Plasmodium.
Origin of recurrent Plasmodium vivax malaria: a new theory.
  • M. Markus
  • Medicine
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde
  • 2011
TLDR
New findings indicate that there might well be a second cause of recurrent P. vivax malaria, thought to originate from a dormant liver form.
Clinical implications of a gradual dormancy concept in malaria
TLDR
It is proposed that 8-aminquinolines may be considered in a relapse-type recrudescence regardless of the causal Plasmodium sp.
Lessons Learned for Pathogenesis, Immunology, and Disease of Erythrocytic Parasites: Plasmodium and Babesia
TLDR
Compared similarities and differences in the pathogenesis of Babesia and host immune responses are compared, showing cellular and innate immunity are critical for the clearance of both pathogens.
Dormancy in mammalian malaria.
  • M. Markus
  • Biology, Medicine
    Trends in parasitology
  • 2012
TLDR
There is indirect evidence that, contrary to what is generally assumed, activation of hypnozoites might not be the only cause of recurrent Plasmodium vivax malaria, and some suggestions are made for demystifying work on hyp nozoites and quiescent merozoites.
Etiopathogenesis and Pathophysiology of Malaria
TLDR
The uncomplicated falciparum malaria clinical frame ranges from asymptomatic infection to classic symptoms such as fever, chills, sweating, headache, and muscle aches, however, malaria can also evolve into severe life-threatening complications, including cerebral malaria, severe anemia, respiratory distress, and acute renal failure.
Malaria Parasites, Traditional Medicinal Plants and Artediffusin (Tehranolide) as a New Candidate of Antimalaria Agent
TLDR
It was shown that Malaria mortality in children under the age of four increased 11-fold within six years of the emergence of the chloroquine-resistance, providing the reasons for research for new anti malarial drugs.
Tafenoquine for the prophylaxis, treatment and elimination of malaria: eagerness must meet prudence.
TLDR
Tafenoquine is a PQ analog with a longer half-life that enables radical cure of malaria with a single dose and overcomes adherence issues associated with PQ, thereby increasing effectiveness in real-life settings.
...
1
2
3
4
...

References

SHOWING 1-10 OF 14 REFERENCES
Targeting the hypnozoite reservoir of Plasmodium vivax: the hidden obstacle to malaria elimination.
TLDR
The only clinical therapy against relapse of vivax malaria is the 8-aminoquinoline, primaquine, which has the drawback of causing haemolysis in genetically sensitive patients and requires 14 days of treatment.
Demonstration of hypnozoites in sporozoite-transmitted Plasmodium vivax infection.
Hypnozoites of two strains of the human relapsing malaria parasite, Plasmodium vivax, have been detected among maturing 7- and 10-day pre-erythrocytic schizonts in liver biopsies of chimpanzees
Relapses in primate malaria: discovery of two populations of exoerythrocytic stages. Preliminary note.
TLDR
The symptoms appearing after the transfusion of the blood unit containing penicillin were identical with those observed after the injection of cephazolin and consistent with an allergic reaction to Penicillin, indicating that the reaction in the patient was related to the presence ofPenicillin in the transfused blood unit.
Seventy-five years of Resochin® in the fight against malaria
TLDR
In regions where it has not been in use against malaria tropica for quite some time due to the development of resistances, Resochin® (chloroquine) has regained some of its efficacy.
Observations on early and late post-sporozoite tissue stages in primate malaria. II. The hypnozoite of Plasmodium cynomolgi bastianellii from 3 to 105 days after infection, and detection of 36- to 40-hour pre-erythrocytic forms.
TLDR
Experiments involving the intravenous injection into susceptible monkeys of 48 to 85 x 10(6) sporozoites derived from mosquitoes of a different species and source than employed previously appeared to rule out the circulation as a vehicle for dissemination of any putative early intermediate hepatotropic forms from another site.
Electron microscopy of stages of Isospora felis of the cat in the mesenteric lymph node of the mouse
TLDR
Stages of Isospora felis of the cat in the mesenteric lymph node of the mouse 25 days after oral inoculation with oocysts, have been described at the ultrastructural level, with a biological function similar to that of the tissue cyst stage of other genera of isosporan coccidia.
Observations on early and late post-sporozoite tissue stages in primate malaria. I. Discovery of a new latent form of Plasmodium cynomolgi (the hypnozoite), and failure to detect hepatic forms within the first 24 hours after infection.
TLDR
Although a new, previously unrecognized, uninucleate latent stage of 5 micrometer diameter (the "hypnozoite") was detected among large maturing schizonts in the 7-day and later biopsies, no intrahepatic parasites were found in tissue taken at 24 hours or earlier, despite the presence of up to 61 7- day schizontS and eight hypnozoites per 5 X 8 mm section.
Rechutes dans la malaria: revue des travaux récents
De nombreuses theories ont ete avancees pour expliquer le phenomene de rechute dans le paludisme. On constate que certains sporozoides se transforment en hypnozoites qui deviennent actifs plus tard
THE MALARIAL HYPNOZOITE
...
1
2
...