First genomic detection of Peaton virus in a calf with hydranencephaly in Israel

Abstract

Simbu serogroup are arbo‐ viruses which are mainly transmitted by Culicoides . Two members of the Simbu serogroup, Akabane and Shuni viruses, have been isolated from congenitally malformed ruminants in Israel. A recent serosurvey revealed that Israeli ruminants have been exposed to several additional Simbu viruses, including Shamonda and Sathuperi that seems to be circulating in Israel. In April 2017, an apparently healthy one‐month‐old male calf was transferred to the Kimron Veterinary Institute. A few days later, the calf was reported to be slow to respond to its surroundings and was not able to feed on its own. Blindness was observed upon clinical examination. RNA of the small, medium and large segments of Simbu serogroup viruses were amplified and sequenced from the testis tissues and from the Cerebrospinal fluid ( CSF ). During post‐mortem examination, hydranencephaly was defined. Phylogenetic analysis of all three segments of Simbu serogroup viruses showed that the sequences detected in the Israeli calf were virtually identical to Peaton virus ( PEAV ). PEAV was also detected in two pools of Culicoides imicola trapped at two different locations in Israel. This is the first genomic detection of PEAV outside Australia and Japan. These results are of epidemiological significance, as they demonstrate that PEAV is circulating in Israel and affects cattle. Consequently, these results are also of relevance to a potential spread of Simbu serogroup viruses into Europe.

Seasonal and spatial variation in Culicoides community structure and their potential role in transmitting Simbu serogroup viruses in Israel

“…Our phylogenetic analysis, performed on representative sequences of L segments (~200 bp), showed that the virus sequences detected in positive pools from C. imicola , C. oxystoma and C. puncticollis were virtually identical to those of SATV, SHUV and PEAV (Figure b). Moreover, SHUV and PAEV sequences obtained from infected midges were identical to previously published sequences obtained from clinical cases occurring in Israel in 2014 and 2017, respectively (Behar et al, ; Golander et al, ).…”

“…Finally, according to our phylogenetic analysis, some of the viral fragments detected from Culicoides pools were identical to the genomic fragments of SHUV and PEAV detected in clinical ruminants during 2014 and 2017, respectively (Behar et al, ; Golender et al, ). Nevertheless, whole‐genome sequencing of viruses isolated from both vectors and ruminants is needed to better understand the transmission of Simbu serogroup viruses by infected Culicoides in Israel.…”

“…Nested qPCR was performed as follows: initial rounds of amplification were performed in 25‐μl reactions containing 4 µl template cDNA and 1 μM external forward and reverse primers (as described above; Fischer et al, ) in a conventional thermocycler for 10 cycles of amplification. For the second round of amplification, 2 μl of the PCR product from the initial amplification was used as the template in a qPCR containing 0.1 µM Simbunest internal primers according to Behar et al (). Known concentrations of SHUV were used as the external standard.…”

“…Samples with a cycle threshold (Ct) value <30 and melting temperature (Tm) of 73°C–81°C were suspected of being Simbu serogroup‐positive. All of these samples were amplified using the Simbunest primers (Behar et al, ) in a conventional PCR (SensoQuest Labcycler, Goettingen, Germany) with 1 µM primer and addition of 20 ng/µl bovine serum albumin (BSA) in 2X Hy‐Tiger XTaq mix (Hylabs) for a total reaction mixture volume of 25 µl. All PCR products were then sequenced in both directions.…”

Reverse Genetics System for Shuni Virus, an Emerging Orthobunyavirus with Zoonotic Potential

“…The most widespread orthobunyavirus is Akabane virus (AKAV), a member of the Simbu serogroup, which is endemic to Africa, Australia, and Asia and causes congenital malformations in ruminants [3]. Other veterinary pathogens of this serogroup include Aino virus, Shamonda virus, and Peaton virus [4,5]. Apart from veterinary pathogens, the genus Orthobunyavirus, also comprises human pathogens, such as Oropouche virus (OROV), which causes a mild, self-limiting febrile illness [6,7].…”