Since the start of the mandatory nationwide bovine viral diarrhea (BVD) eradication program in Germany in 2011, the number of persistently infected (PI) animals has decreased considerably, resulting in a continuous decrease in seroprevalence. The increasingly BVD-naive cattle population could facilitate spillover infections with non-BVDV ruminant pestiviruses. Here, we report two cases in which novel pestiviruses were isolated from cattle; in both cases, the whole genome sequence showed the highest level of identity to strain “Pestivirus reindeer-1”. Both novel viruses gave positive results in BVDV diagnostic test systems, confirming that cross-reactivity is an important issue in pestivirus diagnostics. In the first case, the pestivirus was probably transmitted from sheep kept with the affected cattle, suggesting that the co-housing of small ruminants and cattle is a risk factor. The source of infection could not be determined in the second case. The occurrence of these two cases in independent cattle holdings within a relatively short time frame suggests that it would be useful to determine the presence of pestiviruses in small ruminants or even wild ruminants to better assess risk factors, especially for BVDV-free populations.

Shamonda virus (SHAV), which has recently emerged in Central Europe and has caused disease in numerous cattle herds, was detected in brain tissue from two horses that showed clinical signs, including neurological disorder, and underwent pathological examination. The horses reportedly exhibited seizure-like episodes (Horse A) as well as fever and ataxia (Horse B). In both horses, severe lymphohistiocytic meningoencephalitis with hemorrhages was observed in various parts of the central nervous system (CNS), while outside the CNS no abnormalities were found. The virus genome could be detected by RT-qPCR in all examined parts of the CNS of both horses. In a postmortem cerebrospinal fluid sample of one horse, the virus could only be detected with a very low genome load; however, postmortem contamination cannot be completely ruled out. Consistent with the histological findings, no SHAV genome was detected in either the blood or organs outside the CNS. Postmortem, CNS material—especially brainstem tissue—is suitable for detection of histological lesions and virus genomes via RT-qPCR, while intravital diagnostics of a SHAV infection in horses exhibiting neurological signs is at the moment only possible to a very limited extent. The epidemiological role of horses in the SHAV outbreak is currently unclear.

Shamonda virus (SHAV), which has recently emerged in Central Europe, was detected in brain tissue from two horses that showed clinical signs including neurological disorder and underwent pathological examination. The horses reportedly exhibited seizure-like episodes (Horse A) as well as fever and ataxia (Horse B). In both horses, severe lymphohistiocytic meningoencephalitis with hemorrhages were observed in various parts of the central nervous system (CNS), while outside the CNS no abnormalities were found. The virus genome could be detected by RT-qPCR in all examined parts of the CNS of both horses. In a postmortem cerebrospinal fluid sample of one horse, the virus could only be detected with a very low genome load; however, postmortem contamination cannot be completely ruled out. Consistent with the histological findings, no SHAV genome was detected in either the blood or organs outside the CNS. Postmortem, CNS material - especially brainstem tissue – is suitable for detection of histological lesions and virus genome via PT-qPCR, while intra vitam diagnostics of a SHAV infection in horses exhibiting neurological signs is at the moment only possible to a very limited extent.