Assessing the occurrence of the novel zoonotic variegated squirrel bornavirus 1 in captive squirrels in Germany —A prevalence study

The newly described zoonotic variegated squirrel bornavirus 1 (VSBV‐1) in German squirrel holdings has been associated with the death of three private owners and one zoo animal caretaker (confirmed cases). Epidemiological investigations were severely impeded by the general lack of data on holdings of the putative reservoir hosts, the family Sciuridae. To fill this lack of data for detailed epidemiological investigations of the captive squirrel population, a register of private and zoological squirrel holdings was established. The findings show a broad variety of kept species and their frequency distribution. By contacting the different stakeholders via Web‐based social groups and societies, information passed in both directions so that disease awareness could be raised and participants could be recruited for further studies. Cross‐sectional studies revealed a prevalence of VSBV‐1‐positive subpopulations of 0% (95% CI 0%–6.2%) among private squirrel collections and 1.9% (95% CI: 0%–9.9%) among zoos in Germany. The approach presented here can be transferred to other populations of non‐traditional pets, which may be equally difficult to monitor, in the case of an emerging zoonotic infectious disease.Peer Reviewe

Does having a cat in your house increase your risk of catching COVID-19?

[EN]Due to the zoonotic origin of SARS-Coronavirus 2 (SARS-CoV-2), the potential for its transmission from humans back to animals and the possibility that it might establish ongoing infection pathways in other animal species has been discussed. Cats are highly susceptible to SARS-CoV-2 and were shown experimentally to transmit the virus to other cats. Infection of cats has been widely reported. Domestic cats in COVID-19-positive households could therefore be a part of a human to animal to human transmission pathway. Here, we report the results of a qualitative risk assessment focusing on the potential of cat to human transmission in such settings. The assessment was based on evidence available by October 2021. After the introduction of SARS-CoV-2 to a household by a human, cats may become infected and infected cats may pose an additional infection risk for other members of the household. In order to assess this additional risk qualitatively, expert opinion was elicited within the framework of a modified Delphi procedure. The conclusion was that the additional risk of infection of an additional person in a household associated with keeping a domestic cat is very low to negligible, depending on the intensity of cat-to-human interactions. The separation of cats from humans suffering from SARS-CoV-2 infection should contribute to preventing further transmission.SIThis work was funded by the German Federal Ministry of Education and Research within the COVMon Project, being part of the InfectControl2020 Initiative (BMBF grant no. 03COV16D)

On the Epidemiology of the Variegated Squirrel Bornavirus 1 in captive squirrels in Germany and Europe

Mit der vorliegenden Arbeit wurde der Überblick bezüglich der Struktur und des Netzwerks der Hörnchenhaltung und -zucht in Deutschland, einer von vielen Nischen bei Tier-Mensch-Schnittstellen, erweitert. Dazu wurden Register für in Zoos und Privathaushalten gehaltene Hörnchen erstellt. Die hierbei auftretenden Schwierigkeiten bezüglich der Erreichbarkeit der betreffenden Personengruppen machten deutlich, dass eine zügige Untersuchung und die Eindämmung eines Infektionsgeschehens erheblich erschwert war. Der Mangel an Daten nicht nur zu Hörnchenhaltungen, sondern auch bezüglich des Besitzes der meisten exotischen Haustiere, ist sowohl im deutschen System als auch dem anderer Länder der Welt inhärent. Die Interaktion mit der Community von Halter*innen und Verkäufer*innen exotischer Haustiere offenbarten das Ausmaß von gehandelten und gehaltenen Arten. Der beschriebene Ansatz kann als Vorlage für die epidemiologische Aufarbeitung neu auftretender Krankheiten bei exotischen Tieren dienen. In auf den Registern aufbauenden Querschnittsstudien wurde für die Hörnchenpopulation in Privathaushalten und die Hörnchenpopulation in Zoos die Prävalenz von Subpopulationen geschätzt, in denen mindestens ein Individuum VSBV-1-infiziert war. Hierzu wurden Maultupfer oder Kotproben von 58 private bzw. 53 zoologische Subpopulationen mittels RT-qPCR auf das Vorhandensein von VSBV-1-spezifischer RNA untersucht. Dabei ergab sich eine VSBV-1-Prävalenz von 0 % (95 % CI 0 – 6,2 %) in privaten Subpopulationen und von 1,9 % (95 % CI 0 – 9,9 %) in Zoo-Subpopulationen. Für die Studienteilnahme wurde über eine Vielzahl von Hörnchen-spezifischen Medien geworben, wodurch innerhalb der Risikopopulation der Hörnchenhalter*innen und –pfleger*innen das Bewusstsein für die potentielle Infektionsgefahr durch ungetestete Hörnchen erhöht werden konnte. Durch Intensivierung der Nachverfolgungsermittlungen in von VSBV-1 betroffenen Hörnchenhaltungen, -subpopulationen und Individuen konnte ein Handelsnetzwerk rekonstruiert werden. Gestützt durch phylogenetische Analysen des Genoms von VSBV-1-Isolaten konnte gezeigt werden, dass das VSBV-1-Geschehen in Deutschland vermutlich auf einen einmaligen Eintrag von VSBV-1 mit einem Prevost-Hörnchen zurückgeht, das Ende der 1990er aus seinem Herkunftsland Indonesien importiert wurde. Von der Haltung des Importeurs wurde das Virus über gehandelte Tiere in Zoos und weitere private Haltungen verbreitet. In einer dieser Haltungen wurde VSBV-1 auf Bunthörnchen übertragen. Somit können sich die zukünftigen Untersuchungen zum Erregerursprung und Wildtierreservoir auf den südostasiatischen Raum konzentrieren.The presented work increases the insight into squirrel husbandry in Germany. Registers for squirrels kept in zoos and private households were created. The difficulties in reaching the population at risk disclosed that the rapid examination and containment of a disease is considerably hampered. The lack of data, not only on squirrel husbandry but also on the ownership of most other exotic pets, is inherent in the German system as well as in that of other countries around the world. Interacting with the community of owners and sellers of exotic pets revealed the extent of traded and kept species. The described approach may serve as a blueprint for the epidemiological investigation of emerging diseases in exotic animals. In cross-sectional studies based on the registers for the squirrel population in private households and the squirrel population in zoos, the prevalence of subpopulations was estimated, in which at least one individual was infected with VSBV-1. To this end, oral swabs or fecal samples from 58 private and 53 zoological subpopulations were analyzed by RT-qPCR for the presence of VSBV-1-specific RNA. This resulted in a prevalence of 0 % (95 % CI 0 - 6.2 %) of VSBV-1 in private subpopulations and 1.9 % (95 % CI 0 - 9.9 %) in zoo subpopulations. Participation in the study was advertised through a variety of squirrel-specific media, thus raising awareness for the potential risk of infection in untested squirrels within the population at risk, e.g. squirrel owners and animal caretakers. By intensifying the follow-up investigations of VSBV-1 affected squirrel holdings, subpopulations and individuals, a trade network could be reconstructed. Supported by phylogenetic analyses, the network pointed to a single entry of VSBV-1 with a Prevost squirrel imported from its country of origin, Indonesia, in the late 1990s. From the importer's husbandry, the virus spread via traded animals to zoos and other private holdings. In one of these holdings, VSBV-1 was transmitted to variegated squirrels. Future research regarding the origin and natural reservoir of VSBV-1 may thus focus on the Southeast-Asian region

Analysis of exotic squirrel trade and detection of human infections with variegated squirrel bornavirus 1, Germany, 2005 to 2018

Following the discovery in 2015 of the variegated squirrel bornavirus 1 (VSBV-1) in fatal encephalitis cases among exotic squirrel breeders and a zoo animal caretaker in Germany, a case definition was developed. It was employed during trace-back animal trade investigations and sero-epidemiological studies among breeders and zoo animal caretakers of holdings with VSBV-1 infected squirrels. During the investigation, two possible human cases who had died of encephalitis were identified retrospectively among the squirrel breeders. Moreover, one probable human case was detected among the breeders who had a positive memory T-cell response to VSBV-1 antigen and antibodies against VSBV-1. The low rate of seropositivity found among living persons in risk groups that handle exotic squirrels privately or at zoos may reflect rareness of exposure to VSBV-1 during animal contact, a high lethality of infection or a combination of these factors. As a precaution against human exposure, testing of exotic squirrels for VSBV-1 infection and/or avoiding direct contact with exotic squirrels in zoos and private holdings is strongly advised.Peer Reviewe

Does having a cat in your house increase your risk of catching COVID-19?

Due to the zoonotic origin of SARS-Coronavirus 2 (SARS-CoV-2), the potential for its transmission from humans back to animals and the possibility that it might establish ongoing infection pathways in other animal species has been discussed. Cats are highly susceptible to SARS-CoV-2 and were shown experimentally to transmit the virus to other cats. Infection of cats has been widely reported. Domestic cats in COVID-19-positive households could therefore be a part of a human to animal to human transmission pathway. Here, we report the results of a qualitative risk assessment focusing on the potential of cat to human transmission in such settings. The assessment was based on evidence available by October 2021. After the introduction of SARS-CoV-2 to a household by a human, cats may become infected and infected cats may pose an additional infection risk for other members of the household. In order to assess this additional risk qualitatively, expert opinion was elicited within the framework of a modified Delphi procedure. The conclusion was that the additional risk of infection of an additional person in a household associated with keeping a domestic cat is very low to negligible, depending on the intensity of cat-to-human interactions. The separation of cats from humans suffering from SARS-CoV-2 infection should contribute to preventing further transmission

Does having a cat in your house increase your risk of catching COVID-19?

Due to the zoonotic origin of SARS-Coronavirus 2 (SARS-CoV-2), the potential for its transmission from humans back to animals and the possibility that it might establish ongoing infection pathways in other animal species has been discussed. Cats are highly susceptible to SARS-CoV-2 and were shown experimentally to transmit the virus to other cats. Infection of cats has been widely reported. Domestic cats in COVID-19-positive households could therefore be a part of a human to animal to human transmission pathway. Here, we report the results of a qualitative risk assessment focusing on the potential of cat to human transmission in such settings. The assessment was based on evidence available by October 2021. After the introduction of SARS-CoV-2 to a household by a human, cats may become infected and infected cats may pose an additional infection risk for other members of the household. In order to assess this additional risk qualitatively, expert opinion was elicited within the framework of a modified Delphi procedure. The conclusion was that the additional risk of infection of an additional person in a household associated with keeping a domestic cat is very low to negligible, depending on the intensity of cat-to-human interactions. The separation of cats from humans suffering from SARS-CoV-2 infection should contribute to preventing further transmission