An outbreak of Getah virus infection among pigs in China, 2017

Abstract

A Getah virus (GETV) outbreak occurred in a swine farm in Hunan, China, between June and July 2017. Approximately 200 piglets died 5-10 days after birth, and more than 150 pregnant sows had stillbirths or foetal mummies in this outbreak. GETV HuN1, isolated from the cerebrum of an infected piglet, shared a close evolutionary relationship with the Kochi/01/2005 strain, isolated from pigs in Japan. GETV was detected in the cerebral cortices of a dead foetus and in various organs of two infected piglets, thereby demonstrating that GETV can be transmitted through the placenta to infected newborn piglets with multiple tissue tropisms. Seroepizootiologic investigation of GETV revealed that a wide infection of GETV had been persisting in the farm between June 1 and July 17. In conclusion, clinical and laboratory diagnostics of the diseased pigs in this outbreak were consistent with GETV being the causative agent. To the best of our knowledge, this is the first unequivocal report of GETV in pigs in China.

Serological Survey of Getah Virus in Domestic Animals in Yunnan Province, China

“…Several GETV outbreaks have occurred in horses and swine in Japan (Bannai et al 2016), India (Broen and Timoney 1998), and China (Yang et al 2018). The results of this study revealed that there is a high titer of the GETV neutralizing antibody in many domestic animals in Yunnan Province, which suggests that GETV may cause infections in domestic animals in the local area.…”

“…In 2017, an outbreak of GETV infection occurred among pigs in Hunan, China. Approximately 200 piglets died 5-10 days after birth, and more than 150 pregnant sows had stillbirths or fetal mummies in this outbreak (Yang et al 2018). Thus, GETV is an important animal pathogen.…”

Isolation and characterization of Getah virus from pigs in Guangdong province of China

“…Getah virus (GETV) is a mosquito‐borne virus of the genus Alphavirus within the family Togaviridae (Chen et al., 2018) widely distributed across Asia and Oceania (Li, Liu, et al, 2017; Lu et al., 2020; Kanamitsu et al., 1979) and with a wide host range, including mosquitoes, horses, pigs, cattle and foxes (Kamada et al., 1980; Li, Liu, et al, 2017; Liu et al., 2019; Shi, Li, Lu, Yan, & Liu, 2019). It can cause fever, rash, hind limb oedema and lymph node enlargement in horses (Lu et al., 2019), while infected piglets exhibit depression, tremors, hind limb paralysis, diarrhoea and high mortality, with abortion in infected sows (Kumanomido et al., 1988; Wang, Chang, & Huang, 2019; Yang et al., 2018). Histopathological examination showed that GETV‐infected pigs displayed degenerative changes (neuronophagia and central chromatolysis) in the neurons, epithelial cell abscission in the alveolar walls, thickening of the renal cortex, haemorrhagic splenitis and so on (Yang et al., 2018).…”

“…It can cause fever, rash, hind limb oedema and lymph node enlargement in horses (Lu et al., 2019), while infected piglets exhibit depression, tremors, hind limb paralysis, diarrhoea and high mortality, with abortion in infected sows (Kumanomido et al., 1988; Wang, Chang, & Huang, 2019; Yang et al., 2018). Histopathological examination showed that GETV‐infected pigs displayed degenerative changes (neuronophagia and central chromatolysis) in the neurons, epithelial cell abscission in the alveolar walls, thickening of the renal cortex, haemorrhagic splenitis and so on (Yang et al., 2018). The GETV genome is a single positive‐stranded RNA of 11–12 kb, two thirds of which encode for non‐structural proteins (NSP1‐4) involved in viral RNA transcription, replication, polyprotein cleavage and RNA capping, with the remainder encoding structural proteins (C, E3, E2, 6K and E1) (Chen et al., 2018).…”

“…The first mosquito GETV strain M1 was isolated in Hainan province in 1964 (Zhai et al., 2008), and since then mosquito‐bearing GETVs have been detected in many provinces, including Hainan, Yunnan, Sichuan, Guizhou, Gansu, Jilin, Hebei and Shanxi. Porcine GETV infection in China was first detected in Taiwan in 2002, then successively in Henan (2005), Hunan (2017), Anhui (2017) and Sichuan (2018) provinces (Jiang et al., 2019; Yang et al., 2018; Zhou et al., 2018). GETV infection in blue fox occurred in Shandong in 2017 and may be associated with porcine GETV products (Shi et al., 2019).…”