Screening of Eurasian Tundra Reindeer for Viral Sequences by Next-Generation Sequencing

Abstract

Reindeer husbandry is essential for the livelihood and culture of indigenous people in the Arctic. Parts of the herding areas are also used as pastures for farm animals, facilitating potential transmission of viruses between species. Following the Covid-19 pandemic, viruses circulating in the wild are receiving increased attention, since they might pose a potential threat to human health. Climate change will influence the prevalence of infectious diseases of both humans and animals. The aim of this study was to detect known and previously unknown viruses in Eurasian tundra reindeer. In total, 623 nasal and 477 rectal swab samples were collected from reindeer herds in Fennoscandia, Iceland, and Eastern Russia during 2016–2019. Next-generation sequencing analysis and BLAST-homology searches indicated the presence of viruses of domesticated and wild animals, such as bovine viral diarrhea virus, bovine papillomavirus, alcephaline herpesvirus 1 and 2, deer mastadenovirus B, bovine rotavirus, and roe deer picobirnavirus. Several viral species previously found in reindeer and some novel species were detected, although the clinical relevance of these viruses in reindeer is largely unknown. These results indicate that it should be possible to find emerging viruses of relevance for both human and animal health using reindeer as a sentinel species.

A Screening for Virus Infections among Wild Eurasian Tundra Reindeer (Rangifer tarandus tarandus) in Iceland, 2017–2019

“…The generated sequences indicate ORFV, which assumingly reflects introduction of the virus to reindeer via sympatric grazing sheep [ 25 ] rather than being enzootic in the reindeer population. The finding of parapoxvirus in clinically healthy animals is supported by previous investigations, reporting parapoxvirus-specific DNA detected by PCR in reindeer carcasses in Finnmark county, with no indications of clinical CE [ 55 ], and in apparently healthy animals from Finnmark, Nordland, and Trøndelag counties, Norway, as indicated by Next Generation Sequencing [ 34 ]. In spite of these findings, clinical CE has been recorded only a few times in Norway [ 19 ], indicating that the presence of the virus alone may not elicit a disease outbreak.…”

“…Except for the recently recorded outbreak of CE, there are no records on outbreaks of viral diseases among Icelandic reindeer. As part of a broader study, including reindeer from Iceland ( n = 49), Norway, Sweden, Finland, and Russia, Reindeer papillomavirus was detected by next generation sequencing (NGS) in a nasal swab pool [ 34 ], but no thorough virological investigations for reindeer pathogens in this wild reindeer population have been reported.…”

Serological screening for tick‐borne encephalitis virus in eight Norwegian herds of semi‐domesticated reindeer (Rangifer tarandus tarandus)

“…Furthermore, the mosquito-borne virus INKV was detected in mosquitoes collected from Røros and INKV-specific antibodies were detected in reindeer from all the reindeer herding areas included in this study (Shakya et al, 2022). In the present study, the TBE ELISA-positive samples came from six out of eight locations from north to south of Norway where viable mosquito populations have been reported by Sánchez Romano et al (2021) and Shakya et al (2022) (Figure 1, Table 1). Most of the positive samples came from Røros in Trøndelag County, followed by…”

“…Unlike ticks, mosquitoes are found all over Norway, including the inland regions (Shakya et al, 2022). Sequencing of RNA from reindeer nasal and/or rectal swabs have identified viral sequences representing the Flaviviridae family in reindeer in Norway, which is hosted mainly by arthropod vectors like ticks and mosquitoes (Romano et al, 2021). Furthermore, the mosquito‐borne virus INKV was detected in mosquitoes collected from Røros and INKV‐specific antibodies were detected in reindeer from all the reindeer herding areas included in this study (Shakya et al, 2022).…”

“…Reindeer are adapted to colder climates than other deer species, having a wider distribution from the coast to higher altitudes, both in the Taiga and Tundra areas (Nowak, 1999). Reindeer have been documented to support enzootic maintenance of viruses like herpesvirus, pestivirus and Hepatitis E virus (Rinaldo et al, 2021; Romano et al, 2021; Sacristán et al, 2021; Tryland et al, 2021). Recently, antibodies against Inkoo virus and Inkoo virus‐specific RNA were detected in reindeer for the first time in Norway which indicates that reindeer are exposed to a wide range of viruses (Shakya et al, 2022).…”