Molecular Surveyor (dhfr & dhps) Methodology

PubMed Search terms malaria AND (dhfr OR dhps OR pfdhfr OR pfdhps OR “molecular marker” OR “molecular markers”)‘

Inclusion criteria for publications:

  • At least one pfdhfr or pfdhps genotype/haplotype from isolate/infection
  • Original data
  • Baseline/pre-treatment infections
  • Marker prevalence must be linked to study site/country

Exclusion criteria for publications:

  • Publication not accessible
  • Publication in another language than English, French, Spanish or Italian
  • Prevalence data that have been previously published (data from original publication is included)
  • Cultured strains (e.g. 3D7)
  • Review articles
  • Post-treatment infections
  • Biased selection of baseline samples (e.g. only treatment failures, half resistant and half sensitive samples)
  • P. falciparum in other organisms than human (i.e., Anopheles)
  • Parasites isolated from other tissues than blood (i.e., placenta)
  • Regionally pooled marker prevalence data (i.e. from West Africa) where the origin of the infection cannot be deduced on country level
  • Genotype prevalence (%) presented in article, without sample size

Decisions and guidance on data extraction and display

  • If only haplotype prevalence (e.g. pfdhfr 51I+59R+108N) is presented in the publication, the genotypes of the single loci (pfdhfr 108N or pfdhfr 51I) are calculated from the haplotype frequencies (as long as there is nothing in the publication indicating that the prevalence of the haplotype is not representative for the prevalence of the single loci).
  • Data in the publication is extracted “as is”, referred publications are not explored to find missing information; study year, study site etc.
  • If there are multiple study sites and the genotype prevalence cannot be separated by site, the combined prevalence for all study sites is displayed with a pin pointing at one of the study sites.