Fatal tick-borne encephalitis virus infection in Dalmatian puppy-dogs after putative vector independent transmission

Figures & data

Figure 1. Histology slide stained with Hematoxylin and Eosin (H&E) showing prominent perivascular cuffing (arrow) with lymphocytes, few plasma cells and some macrophages and formation of multiple glial nodules (star). Quadrigeminal bodies, mesencephalon. Scale bar: 100 µm.

Table 1. RT-qPCR results for tick-borne encephalitis virus (TBEV).

Animal-ID	Cq	Organ
S19-1708	21.54	Brain
	n.d.	Lung, liver, spleen, kidney
	n.d.	Heart, lung, bladder
	n.d.	Lung, intestine, thymus, pancreas, lymph node
S19-1722	19.70	Brain
	n.d.	Kidney, spleen, liver, lymph node
	37.84	Heart, lung, lymph node
	31.99	Intestine, thymus, lymph node, tonsil, bone marrow
S19-1723	23.75	Brain
	n.d.	Kidney, liver, lymph node
	29.17	Heart, lung
	33.16	Spleen, intestine, tonsil, thymus, lymph node

[n.d.] not detectable.

Shown are the cq values for RT-qPCR TBEV performed on total RNA extracted from the brain and extra-neural organs (FFPE tissues) of the three puppies. Extra-neural organs include RNA extracted from several tissue types, because they were embedded in the same FFPE tissue block.

Figure 2. Detection of tick-borne encephalitis virus (TBEV) RNA in the brain of three Dalmatian puppies by in situ hybridization (ISH). Positive hybridization signals shown as red granular staining can be seen in the claustrum of puppy ‘S19-1708’ (a). Positive signals for TBEV RNA can be seen in the thalamus of puppy ‘S19-1722’ (B) and in the thalamus of puppy ‘S19-1723’ (C). No in situ detection of TBEV RNA in the brain of a healthy young dog serving as a negative control (D). Scale bars: 100 µm.

Figure 3. Phylogenetic comparison of whole genome sequences of representative tick-borne encephalitis virus (TBEV) strains from the three main subtypes. Representative full-length sequences were obtained from NCBI GenBank with corresponding accession numbers shown in brackets. Colors indicate the three different TBEV subtypes (green: European subtype [TBEV-Eu], red: Far Eastern subtype [TBEV-Fe], blue: Siberian subtype [TBEV-Sib]). The obtained consensus sequence of puppy ‘S19-1723’, TBEV-Eu-Switzerland-2019-Thurgau (bold), clusters with the European subtypes.

Data availability statement

Raw sequencing reads generated and analysed are available at the National Center for Biotechnical Information (NCBI) sequence read archive under the Accession Number PRJNA1014446. The genome of TBEV-EU-Switzerland-2019-Thurgau is available at NCBI GenBank under the Accession Number OR523238.