Judith Köster

The first detection of the Shamonda virus in Central Europe occurred in mid-June 2026. Direct detection of the virus in blood or cerebrospinal fluid from living horses has not yet been reliably achieved. Serological examinations could therefore be crucial for future diagnostics. This study aimed to determine whether clinically healthy horses develop antibodies against viruses of the simbu serogroup and at what point the first positive antibody titers can be detected. To this end, blood sera from eleven clinically healthy horses based in southern Germany were examined retrospectively at three different time points between June and September 2026. Serological testing was performed using the ID Screen® Schmallenberg virus Multi-species ELISA kit; Innovative Diagnostics, Grabels, France. The results showed that all horses were seronegative or doubtful (one horse) in June (time point 1) and seronegative in July 2026 (time point 2). All eleven horses tested positive for antibodies in August or September (time point 3). There was a significant increase in antibody titers between time point 1 and time point 3, as well as between time point 2 and time point 3. The study found that even clinically healthy horses had been exposed to the pathogen and developed antibodies. Therefore, a positive antibody titer is not necessarily associated with clinical disease.

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.

Pestiviruses such as bovine viral diarrhea virus (BVDV) or the ovine border disease virus (BDV) are not strictly species-specific and can be transmitted be

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.

In Europe, raccoons are invasive neozoons with their largest population in Germany. Globally, this mesocarnivore acts as a wildlife reservoir for many (non-)zoonotic (re-)emerging pathogens, but very little epidemiological data is available for southwest Germany. This exploratory study aimed to screen free-ranging raccoons in Baden-Wuerttemberg (BW, Germany) for the occurrence of selected pathogens with One Health relevance. Organ tissue and blood samples collected from 102 animals, obtained by hunters in 2019 and 2020, were subsequently analysed for two bacterial and four viral pathogens using a qPCR approach. Single samples were positive for the carnivore protoparvovirus-1 (7.8%, n = 8), canine distemper virus (6.9%, n = 7), pathogenic Leptospira spp. (3.9%, n = 4) and Anaplasma phagocytophilum (15.7%, n = 16). West Nile virus and influenza A virus were not detected. Due to their invasive behaviour and synanthropic habit, raccoons may increase the risk of infections for wildlife, domestic animals, zoo animals and humans by acting as a link between them. Therefore, further studies should be initiated to evaluate these risks.