PLoS ONE (Jan 2011)

Features and prognosis of severe malaria caused by Plasmodium falciparum, Plasmodium vivax and mixed Plasmodium species in Papua New Guinean children.

  • Laurens Manning,
  • Moses Laman,
  • Irwin Law,
  • Cathy Bona,
  • Susan Aipit,
  • David Teine,
  • Jonathan Warrell,
  • Anna Rosanas-Urgell,
  • Enmoore Lin,
  • Benson Kiniboro,
  • John Vince,
  • Ilomo Hwaiwhanje,
  • Harin Karunajeewa,
  • Pascal Michon,
  • Peter Siba,
  • Ivo Mueller,
  • Timothy M E Davis

DOI
https://doi.org/10.1371/journal.pone.0029203
Journal volume & issue
Vol. 6, no. 12
p. e29203

Abstract

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BACKGROUND: Mortality from severe pediatric falciparum malaria appears low in Oceania but Plasmodium vivax is increasingly recognized as a cause of complications and death. The features and prognosis of mixed Plasmodium species infections are poorly characterized. Detailed prospective studies that include accurate malaria diagnosis and detection of co-morbidities are lacking. METHODS AND FINDINGS: We followed 340 Papua New Guinean (PNG) children with PCR-confirmed severe malaria (77.1% P. falciparum, 7.9% P. vivax, 14.7% P. falciparum/vivax) hospitalized over a 3-year period. Bacterial cultures were performed to identify co-incident sepsis. Clinical management was under national guidelines. Of 262 children with severe falciparum malaria, 30.9%, 24.8% and 23.2% had impaired consciousness, severe anemia, and metabolic acidosis/hyperlactatemia, respectively. Two (0.8%) presented with hypoglycemia, seven (2.7%) were discharged with neurologic impairment, and one child died (0.4%). The 27 severe vivax malaria cases presented with similar phenotypic features to the falciparum malaria cases but respiratory distress was five times more common (P=0.001); one child died (3.7%). The 50 children with P. falciparum/vivax infections shared phenotypic features of mono-species infections, but were more likely to present in deep coma and had the highest mortality (8.0%; P=0.003 vs falciparum malaria). Overall, bacterial cultures were positive in only two non-fatal cases. 83.6% of the children had alpha-thalassemia trait and seven with coma/impaired consciousness had South Asian ovalocytosis (SAO). CONCLUSIONS: The low mortality from severe falciparum malaria in PNG children may reflect protective genetic factors other than alpha-thalassemia trait/SAO, good nutrition, and/or infrequent co-incident sepsis. Severe vivax malaria had similar features but severe P. falciparum/vivax infections were associated with the most severe phenotype and worst prognosis.