Leishmania infection in blood donors: A new challenge in leishmaniasis transmission?

Abstract

Transfusion-transmitted leishmaniasis has been a concern in regions endemic for the disease. Whether immediate or delayed, the risks posed by this mode of transmission call for careful assessment. The purpose of this study was to detect Leishmania infection in blood donors living in an endemic area and to investigate progression to the disease in these individuals. Immunofluorescent antibody test, enzyme-linked immunosorbent assay, leishmaniasis rapid test, and the polymerase chain reaction were applied to 430 donors in an initial evaluation. Of those donors with at least one positive test, 50 were reevaluated four years later by the same methods, as were 25 controls who had been negative on the same tests. In the first evaluation, Leishmania infection was detected in 41.4% (95% CI: 36.7–46.1) of donors (n = 430). None of the 75 reevaluated individuals had developed the disease, but retesting revealed positivity in at least one test in 36.0% (95% CI: 25.1–46.9) of donors. Of the 50 initially testing positive, 50% remained so on retesting. Of the 25 initially negative controls, two tested positive in the subsequent evaluation. The severity of the parasitosis and the risk of transfusion transmission warrant investigation of the potential inclusion of methods for Leishmania detection into blood banks for effective screening of infected donors.

Evaluation of methods for detection of asymptomatic individuals infected with Leishmania infantum in the state of Piauí, Brazil

“…infantum and false-negative test results underestimate the actual rate. However, ELISA can identify asymptomatic infections as is shown in the present study and also in other studies [6,53,54]. In addition, the ELISA method using crude antigen is generally more sensitive, albeit less specific [11].…”

“…Furthermore, blood transfusion is known to be another form of transmission of the parasite described in endemic areas and a cause for much concern since healthy uninfected donors are similar to asymptomatic infected donors. [4–6]. Indeed, in endemic areas in Brazil most people infected with L .…”

One Health Approach to Leishmaniases: Understanding the Disease Dynamics through Diagnostic Tools

“…HIV coinfection can also often induce atypical leishmaniases, for instance, infections with L. (L.) amazonensis [ 59 ] and L. (V.) braziliensis [ 58 ] can cause VL. Several reported cases in endemic countries show VL can be transmitted through a non-vector transmission route, such as blood transfusion [ 60 , 61 ] or via the sharing of needles between intravenous drug users [ 62 ]. Congenital VL cases, although extremely rare in humans, were found to be the predominant route of transmission among canines in the U.S. [ 63 ], suggesting Leishmania ’s potential in invading the placenta [ 64 ] (reviewed in [ 65 ]).…”

Role of asymptomatic and symptomatic humans as reservoirs of visceral leishmaniasis in a Mediterranean context

“…Even though asymptomatic, patient 25 was HIV coinfected, a condition that doesn't not represent what happens in VL immunocompetent patients, it is well established that blood of immunosuppressed patients is more infective to sand flies than blood from immunocompetent subjects due to circulating parasites [16,19,20]. Additionally, blood banks must manage blood (including leukoreduction) from donors living in endemic areas of leishmaniasis with particular caution to prevent transmission of leishmaniasis by transfusion [32,37].…”