Molecular Epidemiology of P. vivax in Iran: High Diversity and Complex Sub-Structure Using Neutral Markers, but No Evidence of Y976F Mutation at pvmdr1.
BACKGROUND
Malaria remains endemic at low levels in the south-eastern provinces of Iran bordering Afghanistan and Pakistan, with the majority of cases attributable to P. vivax. The national guidelines recommend chloroquine (CQ) as blood-stage treatment for uncomplicated P. vivax, but the large influx of imported cases enhances the risk of introducing CQ resistance (CQR).


RESULTS
The genetic diversity at pvmdr1, a putative modulator of CQR, and across nine putatively neutral short tandem repeat (STR) markers were assessed in P. vivax clinical isolates collected between April 2007 and January 2013 in Hormozgan Province, south-eastern Iran. One hundred blood samples were collected from patients with microscopy-confirmed P. vivax enrolled at one of five district clinics. In total 73 (73%) were autochthonous cases, 23 (23%) imported cases from Afghanistan or Pakistan, and 4 (4%) with unknown origin. 97% (97/100) isolates carried the F1076L mutation, but none carried the Y976F mutation. STR genotyping was successful in 71 (71%) isolates, including 57(57%) autochthonous and 11 (11%) imported cases. Analysis of population structure revealed 2 major sub-populations, K1 and K2, with further sub-structure within K2. The K1 sub-population had markedly lower diversity than K2 (HE = 0.06 vs HE = 0.82) suggesting that the sub-populations were sustained by distinct reservoirs with differing transmission dynamics, possibly reflecting local versus imported/introduced populations. No notable separation was observed between the local and imported cases although the sample size was limited.


CONCLUSIONS
The contrasting low versus high diversity in the two sub-populations (K1 and K2) infers that a combination of local transmission and cross-border malaria from higher transmission regions shape the genetic make-up of the P. vivax population in south-eastern Iran. There was no molecular evidence of CQR amongst the local or imported cases, but ongoing clinical surveillance is warranted.
Infectious and Tropical Diseases Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan Province, Iran.
Yaghoob
Y
Hamedi
Infectious and Tropical Diseases Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan Province, Iran.
Khojasteh
K
Sharifi-Sarasiabi
Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan Province, Iran.
Farzaneh
F
Dehghan
Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan Province, Iran.
Reza
R
Safari
Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.
Sheren
S
To
Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.
Irene
I
Handayuni
Bioinformatics Laboratory, Eijkman Institute for Molecular Biology, Jakarta, Indonesia.|The Ministry of Research and Technology (RISTEK), Jakarta, Indonesia.|Agency for Assessment and Application of Technology, Jakarta, Indonesia.
Hidayat
H
Trimarsanto
Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.|Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.
Ric N
RN
Price
Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.
Sarah
http://orcid.org/0000-0002-4638-536X
S
Auburn
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019943:Amino Acid Substitution / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000235:genetics; D004351:Drug Resistance / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D060005:Genotyping Techniques; D006801:Humans; D007492:Iran / Q000453:epidemiology; D015810:Linkage Disequilibrium / Q000235:genetics; D016780:Malaria, Vivax / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics*; D010966:Plasmodium vivax / Q000235:genetics*; D015800:Protozoan Proteins / Q000235:genetics*; D055815:Young Adult
D016054:DNA, Protozoan; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D015800:Protozoan Proteins; C541684:Mdr1 protein, Plasmodium vivax