Identification of Pulmonary Infections With Porcine Rotavirus A in Pigs With Respiratory Disease

Abstract

While rotavirus (RV) is primarily known to cause gastroenteritis in many animals, several epidemiological studies have shown concurrent respiratory symptoms with fecal and nasal virus shedding. However, respiratory RV infections have rarely been investigated. By screening clinical samples submitted for diagnostic testing, porcine rotavirus A (RVA) was detected by quantitative reverse transcription PCR (qRT-PCR) in 28 out of 91 (30.8%) lungs obtained from conventionally reared pigs with respiratory signs. Among the positive cases, intensive RVA signals were mainly localized in alveolar macrophages (n = 3) and bronchiolar epithelial cells (n = 1) by RNAscope®in situ hybridization (ISH). The signals of RVA in bronchiolar epithelial cells were verified by ISH with different probes, immunohistochemistry, and transmission electron microscopy. Furthermore, additional cases with RVA ISH-positive signals in alveolar macrophages (n = 9) and bronchial epithelial cells (n = 1) were identified by screening 120 archived formalin-fixed and paraffin-embedded lung samples using tissue microarrays. Overall, our study showed a high frequency of RVA detection in lungs from conventional pigs with respiratory disease. Further research is needed to determine if RVA infection in the respiratory epithelium correlates with nasal shedding of rotavirus and its contribution to respiratory disease.

Commentary: Identification of pulmonary infections with porcine Rotavirus A in pigs with respiratory disease

“…All these two approaches showed that RVA could indeed infect the lungs. In addition, this study also showed that higher RVA infection rates occurred in pigs aged from 1 day to 8 weeks than in the lungs of pigs with unknown ages (1). A comprehensive understanding of RV infection in the lungs should be further studied.…”

“…It was reported that RV has the tendency of eosinophilic cells ( 6 , 9 ). RV could be detected in nasal mucosa cells and epithelial cells of the lung, such as more and complex bronchiolar epithelial cells, goblet epithelial cells in the intestinal tract ( 1 ). In addition, there are a massive of immune cells in the lung, such as alveolar macrophage and monocyte-macrophage lineage cells.…”

“…Generally speaking, fecal swabs and intestinal samples are candidates for detecting rotavirus, but not respiratory tissues such as the lungs, resulting in low detection rates or inaccurate test results. However, the routine was broken in a previous study ( 1 ).…”

“…Recently, we read significant research entitled “ Identification of pulmonary infections with porcine Rotavirus A in pigs with respiratory diseas e” published in Frontiers in Veterinary Science, with great interest ( 1 ). We want to share our comments regarding the importance of the high detection rate of Rotavirus A in the lungs of pigs in this interesting research.…”

Intestinal mucin-type O -glycans: the major players in the host-bacteria-rotavirus interactions

“…Recently, a similar observation has been demonstrated for porcine RVA. 62 Further, Ciarlet and coauthors observed efficient replication of RVA on cell lines derived from intestine, stomach, breast, bone and lung. 63 The wide range of cells permissive for RVA replication may be explained by the presence of common attachment sites in all of these cell types, such as integrins that was reported to enable RVA replication in Chinese hamster ovary cells.…”