Mylonaki et al.
Tick-borne encephalitis virus RNA found in frozen goat´s milk in a family outbreak
Int J Mol Sci. 2022;23(19):11632. doi:10.3390/ijms231911632
TBE virus infections by consumption of non-pasteurized milk and milk products are relatively rare compared to the transmission of the virus by tick bites. Non-vectorial transmission of viruses has been the topic of the Newsletter October 2022.
A probable case of a TBE outbreak has recently been reported in Austria. The index patient was a 39-year-old man admitted to a hospital in the city of Salzburg, Austria, who had various clinical symptoms: headache, high fever, photophobia. His son and wife who suffered from similar symptoms were also admitted to the hospital three and eight days later, respectively.
A broad clinical laboratory analysis was carried out including serological studies. Both, CSF and blood samples showed positive TBE IgM and IgG antibodies. The diagnosis was confirmed by the reference laboratory of the Centre of Virology of the Medical University of Vienna.
The family could not remember a tick bite, but it was ascertained that they had been consuming non-pasteurized goat milk from a farm near Braunau in Upper Austria two weeks prior to the onset of illness. Neither the index patient nor his wife had been vaccinated, while the son had a non-regular primary vaccination. A container of the frozen goat milk was tested for TBE virus by RT-qPCR and was found positive.
This example should remind travelers in TBE endemic areas to keep in mind that TBE virus infections is not only transmitted by ticks but also by consuming non-pasteurized milk and milk products.