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An outbreak of a disease with multiple erosive papules and ulcers on the lips, noses, and tongues of calves was reported in Taiwan in August 2023. Five of 11 2–4-month-old dairy calves were affected. Oral swabs, nasal swabs, and esophageal–pharyngeal fluid were collected and tested positive for bovine papular stomatitis virus (BPSV) via quantitative real-time polymerase chain reaction assay (qPCR) for all of the affected calves. All of the positive calves remained positive for BPSV after 1 month of the outbreak, and the viral loads of the affected calves did not decrease within this period. To determine the genetic characteristics of this outbreak strain, phylogenetic analysis was performed with the partial B2L sequence of BPSV. The results revealed that the virus strain was closely related to isolates from Japan, the United States, and France. This is the first report on an outbreak in this particular region since 1988 and the first molecular characterization of BPSV in Taiwan.

This is a retrospective study of data analyses from 201 cases with keratoconjunctivitis sicca (KCS) referred to the National Taiwan University Veterinary Hospital, Taiwan. There were 23 breeds in the study, with three most affected breeds, namely Shih-Tzu, Maltese and American cocker spaniel, making up 59.2% of the cases. Among all cases, the mean age at onset of clinical signs was eight years and one month, with no statistical difference between females and males. Clinical signs consisted mainly of corneal pigmentation, mucopurulent discharge and corneal ulceration. In contrast, Shih-Tzu and Malteses showed higher incidence of corneal ulceration. Severe corneal pigmentation occurred in Shih-Tzu. There was no significant difference in mucopurulent discharge in all breeds. The results of this study revealed interbreed differences with respect to sex, age and risks of corneal pigmentation, and corneal ulceration that have not been detailed previously in a referral population in Taiwan.

Between January 20 and April 30 of 2014, a total of 103 diarrhea cases from 47 herds in 13 counties were submitted to the Animal Health Research Institute. In 20 of the 25 herds with detail history, severe diarrhea and vomiting occurred in pigs of all ages, with mortality approaching 100% in suckling pigs. The differential etiologies, including transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhea virus (PEDV), and porcine group A rotavirus (GARV), were tested by reverse transcription polymerase chain reaction (RT-PCR). The RT-PCR of PEDV was positive in 79 cases of 34 herds. Attempts to isolate PEDV in Vero cells revealed that only 7 specimens from 7 herds showed the cytopathic effects (CPEs) of fusion and syncytia. These CPEs were indeed caused by PEDV, as confirmed by RT-PCR, sequencing, and electron microscopy. Sequence comparisons of diarrhea samples and isolated PEDV were assayed by MEGA 5.2 software. The newly isolated PEDV/Taiwan/2014 strains were clustered in group 2 as novel PEDV, together with strains PEDV/USA/2013, PEDV/China/2011–2013, PEDV/Thailand/2007–2008, and PEDV/Korea/2008–2009, whereas the classical CV777 strain was placed in a separate group 1. These results indicated that a novel PEDV was the cause of the recent new outbreak of diarrhea in Taiwan.

Bats can serve as natural reservoirs for severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome coronavirus (MERS-CoV). Investigating the prevalence of bat CoV is critical for assessing the risks of the outbreaks of emerging CoV. Chestnut bats (Scotophilus kuhlii) were captured in this study for detecting the partial RNA-dependent RNA polymerase (RdRp) gene in their feces through reverse transcription polymerase chain reaction (RT-PCR) and antibodies to the nucleocapsid (N) protein of bat CoV through western blotting (WB) analysis. Three recombinant N protein fragments (N1, N2, N3) of the isolated Scotophilus bat CoV/CYCU-S1/TW/2013 were expressed by Escherichia coli. WB analyses were performed with bat serum samples and the sera of a patient who recovered from a SARS-CoV infection. Fragment N2 contained a highly conserved motif among CoVs whereas N1 and N3 protein fragments were specific to the S. kuhlii bat CoV. A total of 32 fecal and 19 serum samples were collected in Changhua County and Yunlin County during 2013 and 2014. About 17 fecal samples tested positive for the RdRp gene with an overall prevalence of 53%. Sequences comparison showed that the Scotophilus bat CoV isolates in Taiwan belonged to the genus Alphacoronavirus and were closest to Scotophilus bat CoV/Hainan/China/2005 and Diliman1552G1/Philippines/2008, followed by porcine epidemic diarrhea coronavirus. Only one bat serum sample reacted positively to all 3N protein fragments. Cross-reactivity was observed between N2 protein fragment and the sera of a patient recovered from a SARS-CoV infection. The results indicated that Scotophilus bat CoV was circulating endemically in chestnut bat population in Taiwan.

Bats are the natural reservoirs of severe acute respiratory syndrome-coronavirus (SARS-CoV). Six Alphacoronavirus and five Betacoronavirus have been detected in many bat species, including SARS-related CoV and Middle East respiratory syndrome (MERS)-related CoV. In Taiwan, SARS-related CoV, belonging to Betacoronavirus, has been detected in Rhinolophus monoceros. Scotophilus bat CoV-512, belonging to Alphacoronavirus, has been detected in Scotophilus kuhlii, Miniopterus fuliginosus, and Rhinolophus monoceros by using reverse transcription polymerase chain reaction (RT-PCR). To understand the infection history of CoV in these three insectivorous bat populations, CoV-specific antibodies were surveyed by using western blot (WB) analysis and indirect enzyme-linked immunosorbent assay (ELISA). The carboxyl terminal fragment of nucleocapsid protein (N3) of SARS-CoV and Scotophilus bat CoV-512 were used as the antigen in the assays. Of the 52 serum samples obtained from Scotophilus kuhlii, 29 samples (56%) were tested positive for Scotophilus bat CoV-512-specific antibodies through ELISA. Of the 63 serum samples obtained from Rhinolophus monoceros, 9 samples were tested positive for only SARS-CoV-specific antibodies, 7 samples were tested positive for only Scotophilus bat CoV-512-specific antibodies, and 16 samples (25.4%) were tested positive for both antibodies through WB analysis. Only 1 of 18 Miniopterus bat serum samples tested positive for Scotophilus bat CoV-512-specific antibodies through ELISA. Lactating female bats had higher positive rates of CoV-specific antibodies than non-lactating female and male bats did. Our findings were crucial for understanding CoV infection history in three insectivorous bat species and important for the control of bat-borne zoonosis diseases.