The hidden Plasmodium malariae in blood donors: a risk coming from areas of low transmission of malaria

Author(s)

Mariana Aschar ^[1] ; José Eduardo Levi ; Maria L. R. N. Farinas ^[3] ; Sandra C. Montebello ^[4] ; Alfredo Mendrone-Junior ^[5] ; Silvia Maria Di Santi

Affiliation

^[1] Universidade de São Paulo. Faculdade de Medicina. Departamento de Moléstias Infecciosas e Parasitárias - Brasil

^[3] Universidade de São Paulo. Faculdade de Medicina. Departamento de Moléstias Infecciosas e Parasitárias - Brasil

^[4] Secretaria da Saúde de São Paulo. Fundação Pró-Sangue Hemocentro de São Paulo - Brasil

^[5] Secretaria da Saúde de São Paulo. Fundação Pró-Sangue Hemocentro de São Paulo - Brasil

• Document type: Journal article
• Source: Revista do Instituto de Medicina Tropical de São Paulo; v. 62, 2020-12-18.

Abstract

ABSTRACT Malaria is an infectious vector-borne disease with other important routes of transmission, such as blood transfusion and organ/tissue transplantation, due to asymptomatic reservoirs of Plasmodium presenting with low parasitemia. Reports of transfusion-transmitted malaria have shown that in immunosuppressed recipients, infections can be fatal if they are not diagnosed and timely treated. All Plasmodium species can survive on blood components at temperatures from 2 to 6 °C for some days or even weeks. This report describes two candidates for blood donation harboring Plasmodium, infected in an area considered non-endemic. Blood samples were collected from donors who attended a blood bank in Sao Paulo and tested by microscopy, qPCR for Plasmodium genus-specific amplification, targeting the parasite 18S ribosomal subunit gene and a multiplex qPCR based on mtDNA of the five species. Under microscopy, only structures resembling Plasmodium were observed. The qPCR whose standard curve tested parasites varying from 2 to 0.1 parasites/ µL, showed the presence of Plasmodium DNA in the two blood donors, as did the multiplex qPCR that revealed the presence of P. malariae. The prevalence of positive donors varies according to the level of transmission, ranging from 0.7 to 55% in endemic areas. In non-endemic regions, prevalences are lower, however, transfusion malaria can evolve to severe cases, due to the lack of suspicion of this transmission route. Asymptomatic donors from low transmission regions pose a risk to blood banks, with particular emphasis on those located in areas with malaria elimination goals. (AU)

• FAPESP's process: 14/50093-8 - Prevention of transfusional transmitted malaria in São Paulo State
• Grantee: José Eduardo Levi
• Support Opportunities: Research Grants - Research in Public Policies for the National Health Care System (PP-SUS)