BACKGROUND: Malaria in humans is caused by apicomplexan parasites belonging to 5 species of the genus Plasmodium. Infections with Plasmodium ovale are widely distributed but rarely investigated, and the resulting burden of disease is not known. Dimorphism in defined genes has led to P. ovale parasites being divided into classic and variant types. We hypothesized that these dimorphs represent distinct parasite species. METHODS: Multilocus sequence analysis of 6 genetic characters was carried out among 55 isolates from 12 African and 3 Asia-Pacific countries. RESULTS: Each genetic character displayed complete dimorphism and segregated perfectly between the 2 types. Both types were identified in samples from Ghana, Nigeria, São Tomé, Sierra Leone, and Uganda and have been described previously in Myanmar. Splitting of the 2 lineages is estimated to have occurred between 1.0 and 3.5 million years ago in hominid hosts. CONCLUSIONS: We propose that P. ovale comprises 2 nonrecombining species that are sympatric in Africa and Asia. We speculate on possible scenarios that could have led to this speciation. Furthermore, the relatively high frequency of imported cases of symptomatic P. ovale infection in the United Kingdom suggests that the morbidity caused by ovale malaria has been underestimated.
BACKGROUND:Malaria in humans is caused by apicomplexan parasites belonging to 5 species of the genus Plasmodium. Infections with Plasmodium ovale are widely distributed but rarely investigated, and the resulting burden of disease is not known. Dimorphism in defined genes has led to P. ovale parasites being divided into classic and variant types. We hypothesized that these dimorphs represent distinct parasite species. METHODS: Multilocus sequence analysis of 6 genetic characters was carried out among 55 isolates from 12 African and 3 Asia-Pacific countries. RESULTS: Each genetic character displayed complete dimorphism and segregated perfectly between the 2 types. Both types were identified in samples from Ghana, Nigeria, São Tomé, Sierra Leone, and Uganda and have been described previously in Myanmar. Splitting of the 2 lineages is estimated to have occurred between 1.0 and 3.5 million years ago in hominid hosts. CONCLUSIONS: We propose that P. ovale comprises 2 nonrecombining species that are sympatric in Africa and Asia. We speculate on possible scenarios that could have led to this speciation. Furthermore, the relatively high frequency of imported cases of symptomatic P. ovale infection in the United Kingdom suggests that the morbidity caused by ovale malaria has been underestimated.
Authors: Mirjam Groger; Luzia Veletzky; Albert Lalremruata; Chiara Cattaneo; Johannes Mischlinger; Rella Zoleko-Manego; Lilian Endamne; Anna Klicpera; Johanna Kim; The Nguyen; Lena Flohr; Jonathan Remppis; Pierre-Blaise Matsiegui; Ayôla A Adegnika; Selidji T Agnandji; Peter G Kremsner; Benjamin Mordmüller; Ghyslain Mombo-Ngoma; Michael Ramharter Journal: Antimicrob Agents Chemother Date: 2018-02-23 Impact factor: 5.191
Authors: Hans-Peter Fuehrer; Markus A Fally; Verena E Habler; Peter Starzengruber; Paul Swoboda; Harald Noedl Journal: J Clin Microbiol Date: 2011-01-26 Impact factor: 5.948
Authors: Khalid B Beshir; Rachel L Hallett; Alice C Eziefula; Robin Bailey; Julie Watson; Stephen G Wright; Peter L Chiodini; Spencer D Polley; Colin J Sutherland Journal: Malar J Date: 2010-11-05 Impact factor: 2.979