Editorial: Emerging swine infectious diseases

Editorial on the Research Topic
Emerging swine infectious diseases

1 Introduction

As major threats to the global swine industry, swine infectious diseases caused significant economic losses and potential public health issues. During the past three decades, many swine infectious diseases emerged in the field, such as porcine reproductive and respiratory syndrome virus (PRRSV) and its novel isolates with distinct pathogenicity, high pathogenic variants of porcine epidemic diarrhea virus (PEDV) and pseudorabies virus (PRV) and influenza viruses, which lead to tremendous economic losses worldwide. A few novel pathogens identified recently, such as Senecavirus A, atypical porcine pestivirus (APPV), porcine circovirus 3 (PCV3), porcine circovirus 4 (PCV4), porcine deltacoronavirus (PDCoV), swine acute diarrhea syndrome coronavirus (SADS-CoV), influenza D virus (IDV), constitute a new challenge (1–5). This Research Topic is focused on filling in some gaps of emerging swine infectious diseases from diverse aspects, such as the pathogenesis mechanisms, structure and function of viral proteins, protective immunity, viral evolution, and new approaches for prevention and treatment.

2 Organization of the Research Topic

In this Research Topic, we received 20 manuscripts, nine (seven original research, one perspective, one brief research report) were accepted for publication. Among them, nine papers all involved virus research. Stelder et al. designed an experiment in Romania to quantify which species of mosquitoes are attracted to Romanian backyard pigs, which species take blood meals from these, and whether these observed feeding behaviors vary throughout the vector season. PRRSV has caused huge economic losses for the global pig industry, but its origins and evolution remain a mystery. According to the genome sequences of seven arteriviruses isolated from rodents in 2018, Zhao et al. offered new analysis showing that they may be ancestors of PRRSV. Sanchez et al. used a spatial and spatiotemporal kernel density approach to estimate PRRSV relative risk and utilized a Bayesian spatiotemporal hierarchical model to assess the effects of environmental variables, between-farm movement data and on-farm biosecurity features on PRRSV outbreaks in the United States.

In order to effectively monitor swine coronaviruses, a quadruplex reverse transcription-polymerase chain reaction (RT-PCR) method for the simultaneous detection of PEDV, PDCoV, TGEV and SADS-CoV was developed by Niu et al., and TaqMan probe-based multiplex real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was developed by Li et al.. By systematical analysis of all available full-length genomes of TGEVs (n = 43) and porcine respiratory coronaviruses PRCVs (n = 7), Wang et al. showed that TGEVs fell into two independent evolutionary phylogenetic clades, GI and GII. Viruses circulating in China (until 2021) clustered with the traditional or attenuated vaccine strains within the same evolutionary clades (GI). To study the cross-reaction and cross-neutralizing activities of antibodies against different genotypes (G) of E2 glycoproteins, ectodomains of G1.1, G2.1, G2.1d, and G3.4 CSFV E2 glycoproteins from a mammalian cell expression system were generated by Chen et al.. To evaluate the virulence reversion potential risk, rPRRSV-E2 had been continuously passaged in vivo, the stability of E2 expression and virulence of the passage viruses were analyzed by Jiang et al.. Sirisereewan et al. investigated the genetic diversity of PCV2 strains circulating in Thailand between 2019 and 2020 using 742 swine clinical samples from 145 farms.

3 Conclusion

Since the July of 2022, The Research Topic began to receive the manuscript submission, and invited more than 24 research teams from the world to submit the manuscript, we finally received 20 manuscripts. Although the Topic provides overviews of some swine emerging pathogen and novel strategies for the detection and control, the manuscripts associated with swine emerging pathogen (especially PCV3, PCV4, IDV) were lacking. In the following work, we hope that more scientists pay more attention to emerging swine infectious diseases.

Author contributions

HG: Writing—original draft. XZ: Writing—original draft. S-LZ: Writing—original draft, Writing—review & editing.

Funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by grants from the Key Areas of Research and Development Program of Guangdong, China (2023B0202150001), the Special fund for the 14th Five-Year Plan of Guangdong Province (2022SDZG02), the Project of Collaborative Innovation Center of GDAAS (XTXM202202 and XT202207), the grant from Guangzhou Science and Technology Bureau (202206010192), and the grant from the Department of Agriculture and Rural Affairs of Guangdong Province (2023KJ114 and 2023KJ119).

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision.

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References

1. Woo PC, Lau SK, Lam CS, Lau CC, Tsang AK, Lau JH, et al. Discovery of seven novel Mammalian and avian coronaviruses in the genus deltacoronavirus supports bat coronaviruses as the gene source of alphacoronavirus and betacoronavirus and avian coronaviruses as the gene source of gammacoronavirus and deltacoronavirus. J Virol. (2012) 86:3995–4008. doi: 10.1128/JVI.06540-11

Crossref Full Text | Google Scholar

2. Hause BM, Ducatez M, Collin EA, Ran Z, Liu R, Sheng Z, et al. Isolation of a novel swine influenza virus from Oklahoma in 2011 which is distantly related to human influenza C viruses. PLoS Pathog. (2013) 9:e1003176. doi: 10.1371/journal.ppat.1003176

PubMed Abstract | Crossref Full Text | Google Scholar

3. Hause BM, Collin EA, Peddireddi L, Yuan F, Chen Z, Hesse RA, et al. Discovery of a novel putative atypical porcine pestivirus in pigs in the USA. J Gen Virol. (2015) 96:2994–8. doi: 10.1099/jgv.0.000251

PubMed Abstract | Crossref Full Text | Google Scholar

4. Palinski R, Piñeyro P, Shang P, Yuan F, Guo R, Fang Y, et al. A novel porcine circovirus distantly related to known circoviruses is associated with porcine dermatitis and nephropathy syndrome and reproductive failure. J Virol. (2016) 91:e01879–16. doi: 10.1128/JVI.01879-16

PubMed Abstract | Crossref Full Text | Google Scholar

5. Zhang HH, Hu WQ, Li JY, Liu TN, Zhou JY, Opriessnig T, et al. Novel circovirus species identified in farmed pigs designated as Porcine circovirus 4, Hunan province, China. Transbound Emerg Dis. (2020) 67:1057–61. doi: 10.1111/tbed.13446

PubMed Abstract | Crossref Full Text | Google Scholar