title: Contrasting Transmission Dynamics of Co-endemic Plasmodium vivax and P. falciparum: Implications for Malaria Control and Elimination.
abstract: BACKGROUND
  Outside of Africa, P. falciparum and P. vivax usually coexist. In such co-endemic regions, successful malaria control programs have a greater impact on reducing falciparum malaria, resulting in P. vivax becoming the predominant species of infection. Adding to the challenges of elimination, the dormant liver stage complicates efforts to monitor the impact of ongoing interventions against P. vivax. We investigated molecular approaches to inform the respective transmission dynamics of P. falciparum and P. vivax and how these could help to prioritize public health interventions.
  
  
  RESULTS
  Genotype data generated at 8 and 9 microsatellite loci were analysed in 168 P. falciparum and 166 P. vivax isolates, respectively, from four co-endemic sites in Indonesia (Bangka, Kalimantan, Sumba and West Timor). Measures of diversity, linkage disequilibrium (LD) and population structure were used to gauge the transmission dynamics of each species in each setting. Marked differences were observed in the diversity and population structure of P. vivax versus P. falciparum. In Bangka, Kalimantan and Timor, P. falciparum diversity was low, and LD patterns were consistent with unstable, epidemic transmission, amenable to targeted intervention. In contrast, P. vivax diversity was higher and transmission appeared more stable. Population differentiation was lower in P. vivax versus P. falciparum, suggesting that the hypnozoite reservoir might play an important role in sustaining local transmission and facilitating the spread of P. vivax infections in different endemic settings. P. vivax polyclonality varied with local endemicity, demonstrating potential utility in informing on transmission intensity in this species.
  
  
  CONCLUSIONS
  Molecular approaches can provide important information on malaria transmission that is not readily available from traditional epidemiological measures. Elucidation of the transmission dynamics circulating in a given setting will have a major role in prioritising malaria control strategies, particularly against the relatively neglected non-falciparum species.
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia.
authors.forename: Rintis
authors.initials: R
authors.lastname: Noviyanti
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia.
authors.forename: Farah
authors.initials: F
authors.lastname: Coutrier
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia.
authors.forename: Retno A S
authors.initials: RA
authors.lastname: Utami
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia; Agency for Assessment and Application of Technology, Jakarta, Indonesia.
authors.forename: Hidayat
authors.initials: H
authors.lastname: Trimarsanto
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia.
authors.forename: Yusrifar K
authors.initials: YK
authors.lastname: Tirta
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia.
authors.forename: Leily
authors.initials: L
authors.lastname: Trianty
authors.affiliation: Eijkman Institute for Molecular Biology, Jakarta Pusat, Indonesia; The Ministry of Research and Technology (RISTEK), Jakarta Pusat, Indonesia.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kusuma
authors.affiliation: Faculty of Medicine, University of Indonesia, Jakarta Pusat, Indonesia.
authors.forename: Inge
authors.initials: I
authors.lastname: Sutanto
authors.affiliation: Faculty of Medicine, University of Indonesia, Jakarta Pusat, Indonesia.
authors.forename: Ayleen
authors.initials: A
authors.lastname: Kosasih
authors.affiliation: National Malaria Control Program, Ministry of Health, Jakarta, Indonesia.
authors.forename: Rita
authors.initials: R
authors.lastname: Kusriastuti
authors.affiliation: United Nations Children's Fund (UNICEF), Jakarta, Jakarta, Indonesia.
authors.forename: William A
authors.initials: WA
authors.lastname: Hawley
authors.affiliation: United Nations Children's Fund (UNICEF), Jakarta, Jakarta, Indonesia.
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Laihad
authors.affiliation: Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States of America.
authors.forename: Neil
authors.initials: N
authors.lastname: Lobo
authors.affiliation: Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.
authors.forename: Jutta
authors.initials: J
authors.lastname: Marfurt
authors.affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom; Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Taane G
authors.initials: TG
authors.lastname: Clark
authors.affiliation: Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia; Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Ric N
authors.initials: RN
authors.lastname: Price
authors.affiliation: Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.
authors.forename: Sarah
authors.initials: S
authors.lastname: Auburn
mesh_terms: D000293:Adolescent; D000328:Adult; D000349:Africa / Q000453:epidemiology; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003140:Communicable Disease Control / Q000379:methods*; D058872:Epidemics; D005260:Female; D005838:Genotype; D006801:Humans; D007214:Indonesia / Q000453:epidemiology; D007223:Infant; D015810:Linkage Disequilibrium; D016778:Malaria, Falciparum / Q000453:epidemiology / Q000635:transmission*; D016780:Malaria, Vivax / Q000453:epidemiology / Q000635:transmission*; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D008875:Middle Aged; D010963:Plasmodium falciparum / Q000235:genetics* / Q000302:isolation & purification; D010966:Plasmodium vivax / Q000235:genetics* / Q000302:isolation & purification; D011634:Public Health; D055815:Young Adult