Citation: Wernike, K.; Drewes, S.;
Mehl, C.; Hesse, C.; Imholt, C.;
Jacob, J.; Ulrich, R.G.; Beer, M. No
Evidence for the Presence of
SARS-CoV-2 in Bank Voles and Other
Rodents in Germany, 2020–2022.
Pathogens 2022, 11, 1112. https://
doi.org/10.3390/pathogens11101112
Academic Editor: Lawrence S. Young
Received: 31 August 2022
Accepted: 26 September 2022
Published: 28 September 2022
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pathogens
Communication
No Evidence for the Presence of SARS-CoV-2 in Bank Voles and
Other Rodents in Germany, 2020–2022
Kerstin Wernike
1,
* , Stephan Drewes
2
, Calvin Mehl
2,3
, Christin Hesse
4
, Christian Imholt
4
, Jens Jacob
4
,
Rainer G. Ulrich
2,3
and Martin Beer
1
1
Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany
2
Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut,
17493 Greifswald-Insel Riems, Germany
3
German Centre for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems,
17493 Greifswald-Insel Riems, Germany
4
Rodent Research, Institute for Epidemiology and Pathogen Diagnostics, Julius Kühn-Institute (JKI),
Federal Research Centre for Cultivated Plants, 48161 Münster, Germany
* Correspondence: kerstin.wernike@fli.de
Abstract: Rodentia is the most speciose mammalian order, found across the globe, with some species
occurring in close proximity to humans. Furthermore, rodents are known hosts for a variety of
zoonotic pathogens. Among other animal species, rodents came into focus when the severe acute
respiratory syndrome coronavirus type 2 (SARS-CoV-2) spread through human populations across
the globe, initially as laboratory animals to study the viral pathogenesis and to test countermeasures.
Under experimental conditions, some rodent species including several cricetid species are susceptible
to SARS-CoV-2 infection and a few of them can transmit the virus to conspecifics. To investigate
whether SARS-CoV-2 is also spreading in wild rodent populations in Germany, we serologically
tested samples of free-ranging bank voles (Myodes glareolus, n = 694), common voles (Microtus arvalis,
n = 2), house mice (Mus musculus, n = 27), brown or Norway rats (Rattus norvegicus, n = 97) and
Apodemus species (n = 8) for antibodies against the virus. The samples were collected from 2020 to
2022 in seven German federal states. All but one sample tested negative by a multispecies ELISA
based on the receptor-binding domain (RBD) of SARS-CoV-2. The remaining sample, from a common
vole collected in 2021, was within the inconclusive range of the RBD-ELISA, but this result could not
be confirmed by a surrogate virus neutralization test as the sample gave a negative result in this test.
These results indicate that SARS-CoV-2 has not become highly prevalent in wild rodent populations
in Germany.
Keywords: coronavirus; COVID-19; reservoir; intermediate host; Cricetidae; Muridae
1. Introduction
The order Rodentia is a highly diverse group, encompassing more than 2000 species
worldwide. Rodents, and representatives of the families Muridae and Cricetidae in par-
ticular, are well-known hosts for a variety of zoonotic pathogens [1]. Because of their
global distribution and high abundance of some species in close proximity to humans in
urban and suburban settings, rodents pose a considerable risk for the back-transmissions
of human pathogens once established in these rodent populations. Given that two (OC43
and HKU1) of the seven currently known human coronaviruses have related ancestors in
rodent species [2] and that additional rodent-specific coronaviruses have been described [3],
it stands to reason that rodents also come into focus when investigating potential reservoir
hosts for the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). SARS-
CoV-2 was initially detected in late 2019 in Wuhan, China, where it caused an outbreak of
an acute respiratory disease in humans [4]. The outbreak of the novel disease, now named
COVID-19 (coronavirus disease 2019), very rapidly evolved into a global pandemic [5],
Pathogens 2022, 11, 1112. https://doi.org/10.3390/pathogens11101112 https://www.mdpi.com/journal/pathogens