A molecular surveillance system for global patterns of drug resistance in imported malaria.

Abstract

Analysis of imported malaria in travelers may represent a novel surveillance system for drug-resistant malaria. We analyzed consecutive falciparum malaria isolates from Canadian travelers from 1994 to 2000, for polymorphisms in pfcrt, dhfr, and dhps linked to chloroquine and pyrimethamine/sulfadoxine resistance. Forty percent of isolates possessed the K76 pfcrt allele, suggesting that many imported falciparum infections are still responsive to chloroquine. Travelers who had recently taken chloroquine had a significantly increased risk of harboring isolates with pfcrt resistance alleles (odds ratio = 4.47; p=0.03). The presence of two or more mutations in dhfr or dhps was found in 64.8% (95% confidence interval [CI] 54.6 to 73.9) and in 30.4% (95% CI 21.7 to 40.3) of isolates, respectively, and increased significantly over the course of the study. These molecular markers indicate that pyrimethamine/sulfadoxine resistance is increasing and is now too high to rely on this drug as a routine therapeutic agent to treat malaria in travelers.

• Authors: Annie-Claude Labbé, Samir Patel, Ian Crandall, Kevin C Kain
• Journal: Emerging infectious diseases (Emerg Infect Dis) Vol. 9 Issue 1 Pg. 33-6 (Jan 2003) ISSN: 1080-6040 [Print] United States
• PMID: 12533279 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antimalarials
• Genetic Markers
• Protozoan Proteins
• Sulfadoxine
• Chloroquine
• Pyrimethamine

Topics

• Adolescent
• Adult
• Aged
• Animals
• Antimalarials (pharmacology)
• Child
• Child, Preschool
• Chloroquine (pharmacology)
• Drug Resistance (genetics)
• Female
• Genetic Markers
• Humans
• Infant
• Malaria, Falciparum (epidemiology, parasitology)
• Male
• Middle Aged
• Mutation
• Plasmodium falciparum (drug effects, genetics)
• Population Surveillance
• Protozoan Proteins (genetics)
• Pyrimethamine (pharmacology)
• Sulfadoxine (pharmacology)
• Travel