First confirmed autochthonous case of human Babesia microti infection in Europe

Abstract

A 42-year-old female patient with acute myeloid leukemia presented with fever and heavy chest pain after her first cycle of specific chemotherapy. Acute myocardial infarction was excluded, but surprisingly, parasitic inclusions in erythrocytes became obvious in Pappenheim and Giemsa-stained peripheral blood smears. The patient did not remember a tick bite but acknowledged having received several blood transfusions in her recent medical history. Suspicion of malaria was ruled out by use of a dip-stick test. The diagnosis of Babesia microti infection was finally established by specific polymerase chain reaction (PCR). Six weeks after initiation of specific treatment, PCR turned negative and a positive immunoflourescence assay (IFA) with an IgG titer of 1:128 indicated seroconversion. Subsequent screening of donors involved in the transfusion of blood products to the patient demonstrated borderline reactivity for Babesia microti (IgG-titer 1:32) in 1 out of 44 individuals. Neither the patient nor the positively tested blood donor had travelled to North America or Asia. Therefore, this is the first confirmed autochthonous human infection in Europe.

Molecular examinations of Babesia microti in rodents and rodent-attached ticks from urban and sylvatic habitats in Germany

“…: JQ880658.1, JX6273569.1. This sequence belongs to the pathogenic B. microti Jena/Germany genotype which was published in the context of the first autochthonous human babesiosis case in Europe [Hildebrandt et al 2007]. The existence of reservoir hosts and bridge vector ticks infected with this particular strain may constitute a risk to human health at the investigated sylvatic site, even though only one human case has been reported in Europe thus far.…”

“…It was first described in a vole near Lisbon in 1910 as Smithia microtia (Microtus incertus, now Microtus arvalis subspecies incertus, the common vole [Walter 1981]. Babesia microti has since been detected in small mammals, humans and hard ticks from Europe and the USA [Kogut et al 2005, Hildebrandt et al 2007, Silaghi et al 2012, Hersh et al 2012. Human babesiosis caused by B.…”

“…However the first and so far only autochthonous human case caused by B. microti in Europe was transmitted by blood transfusion [Hildebrandt et al 2007]. While transovarial transmission in ticks was confirmed for B. divergens and other Babesia species, experimentations have failed to demonstrate transovarial transmission for B. microti [Gray et al 2010].…”

Survey for Tick-Borne Zoonoses in the State of Espirito Santo, Southeastern Brazil

“…22 In the North Hemisphere, human babesiosis is found in the United States, where three different species are known to occur, and also in Europe, where the main species identified in humans are Babesia divergens , Babesia microti , and Babesia odocolei . [23][24][25] South America has a low number of reports of human babesiosis, including the first suspect case from the State of Pernambuco, a serological study in Colombia, a possible positive case in Poland that seems to have been acquired in Brazil, antibodies to Babesia in a study of co-infection with Lyme disease, and a case of a child with hepatoblastoma with a positive blood smear that suggests Babesia infection. [26][27][28][29][30] With the aim to investigate tick-borne zoonoses and to establish epidemiological data about these diseases in the northern region of the State of Espírito Santo, we visited six counties in this area, and performed serology and molecular biology to the most common tick-borne diseases in humans and domestic animals in Brazil.…”

Detection of Two Zoonotic Babesia microti Lineages, the Hobetsu and U.S. Lineages, in Two Sympatric Tick Species, Ixodes ovatus and Ixodes persulcatus, Respectively, in Japan

“…Symptomatic human cases of the U.S. parasite have been reported almost exclusively in the northeastern and upper midwestern United States (11,12,30), while in Europe only a single autochthonous case caused by the U.S. parasite has been described (10). No human case with this parasite lineage has been described in Asia.…”