Nosocomial Plasmodium falciparum infections confirmed by molecular typing in Medellín, Colombia

Abstract

Three cases of nosocomial malaria are reported from patients of the Internal Medicine Ward of a tertiary University teaching hospital in Medellin, Colombia. Epidemiological research, based on entomological captures, medical records review and interviews of nursery staff about patient care practices potentially involving contact with blood, were carried out. Molecular characterization of Plasmodium falciparum was based on the amplification of MSP1, MSP2 and GLURP genes. This method enabled confirmation of the same P. falciparum genotype in all three patients as well as in a fourth one (index case). The presence of nosocomial malaria was confirmed and it was concluded that the most likely source of transmission was through multi-dose preparations of heparin applied to heparin locks.

Figure 1

Dates, chronology of exposure, place of contact and time of malaria diagnosis of the index case and the 3 patients with nosocomial malaria. Each bar represents the location of each patient during the stay at the hospital.

Figure 2

Agarose gel electrophoresis showing the size of the amplified products of the genes MSP-1 (panel A), MSP-2 (panel B) and GLURP (panel C). MW represents the molecular weight marker,(-) a negative control and (+) a positive control. The numbers are equivalent to the case number. Panel A corresponds to allelic family MAD-20 of MSP-1 showing amplification products of ~150 bp in the cases, panel B corresponds to allelic family IC50 showing amplification products of ~450 bp in the cases, panel C corresponds to GLURP showing amplification products of ~700 bp in the cases.