title: The unique distribution of the Plasmodium vivax merozoite surface protein 1 in parasite isolates with short and long latent periods from the Republic of Korea.
abstract: BACKGROUND
  Vivax malaria occurring in the Republic of Korea is occasionally characterized by a long latent infection induced by hypnozoites in the liver. So far, the mechanisms responsible for short and long latent infections of vivax malaria are not known. Therefore, the present study classified the parasite isolates according to the long and short latent periods and then analysed the genetic diversity of the Plasmodium vivax merozoite surface protein 1 (PvMSP-1).
  
  
  METHODS
  Blood samples containing P. vivax isolates were collected from 465 patients from 2011 to 2013 at health centers in the Republic of Korea. PvMSP-1 gene sequences were analysed in groups classified by the collection year, and short or long latent periods. The samples in short and long latent periods were selected by the timing of vivax malaria occurrence, July-August and January-May, respectively.
  
  
  RESULTS
  Three PvMSP-1 types (Sal-1, Belem, and recombinant) were observed in P. vivax isolates collected from 2011 to 2013. Interestingly, the recombinant and Sal-1 types were dominant in vivax malaria of the long and short latent periods, respectively. In addition, the S-b like subtype of the PvMSP-1 Sal-1 type was first identified in 2013.
  
  
  CONCLUSIONS
  This study revealed that the genetic type of PvMSP-1 is likely related to the duration of its latent period. Moreover, trends of the genetic types of PvMSP-1 seem to be stable in recent years compared with those of previous years in which various new types were observed.
authors.affiliation: Division of Malaria and Parasitic Diseases, National Institute of Health, Korea CDC, Osong Saeng-myeong 2 ro, Osong Health Technology Administration, Osong, Republic of Korea. kuku1819@knu.ac.kr.|Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, 700-422, Republic of Korea. kuku1819@knu.ac.kr.
authors.forename: Youn-Kyoung
authors.initials: YK
authors.lastname: Goo
authors.affiliation: Division of Malaria and Parasitic Diseases, National Institute of Health, Korea CDC, Osong Saeng-myeong 2 ro, Osong Health Technology Administration, Osong, Republic of Korea. june_moon@daum.net.
authors.forename: Jun-Hye
authors.initials: JH
authors.lastname: Moon
authors.affiliation: Division of Malaria and Parasitic Diseases, National Institute of Health, Korea CDC, Osong Saeng-myeong 2 ro, Osong Health Technology Administration, Osong, Republic of Korea. amme07@hanmail.net.
authors.forename: So-Young
authors.initials: SY
authors.lastname: Ji
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, 700-422, Republic of Korea. dichung@knu.ac.kr.
authors.forename: Dong-Il
authors.initials: DI
authors.lastname: Chung
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, 700-422, Republic of Korea. ychong@knu.ac.kr.
authors.forename: Yeonchul
authors.initials: Y
authors.lastname: Hong
authors.affiliation: Division of Malaria and Parasitic Diseases, National Institute of Health, Korea CDC, Osong Saeng-myeong 2 ro, Osong Health Technology Administration, Osong, Republic of Korea. jo4u@cdc.go.kr.
authors.forename: Shin-Hyung
authors.initials: SH
authors.lastname: Cho
authors.affiliation: Division of Malaria and Parasitic Diseases, National Institute of Health, Korea CDC, Osong Saeng-myeong 2 ro, Osong Health Technology Administration, Osong, Republic of Korea. leewonja@gmail.com.
authors.forename: Won-Ja
authors.initials: WJ
authors.lastname: Lee
authors.affiliation: Division of Malaria and Parasitic Diseases, National Institute of Health, Korea CDC, Osong Saeng-myeong 2 ro, Osong Health Technology Administration, Osong, Republic of Korea. jykim-malaria@nih.go.kr.
authors.forename: Jung-Yeon
authors.initials: JY
authors.lastname: Kim
mesh_terms: D015331:Cohort Studies; D016054:DNA, Protozoan / Q000032:analysis / Q000235:genetics; D004274:DNA, Recombinant / Q000235:genetics; D006801:Humans; D016780:Malaria, Vivax / Q000453:epidemiology / Q000469:parasitology*; D020066:Merozoite Surface Protein 1 / Q000235:genetics*; D010966:Plasmodium vivax / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D056910:Republic of Korea / Q000453:epidemiology
chemical_list: D016054:DNA, Protozoan; D004274:DNA, Recombinant; D020066:Merozoite Surface Protein 1