Background and Aim: The Sunda pangolin (Manis javanica) is on the International Union for Conservation of Nature Red List of Threatened Species (critically endangered) due to high levels of illegal trafficking for its products. Thailand is one of the habitats of this species, and it has become the main hub for its illegal trafficking. Rehabilitating these captive pangolins and reintroducing them back to the wild are challenging due to the limited knowledge on their diet, management, and diseases. Hemoparasites, including Babesia spp., can cause important protozoal infections in both domestic and wild animals, resulting in the failure of rehabilitation and conservation programs. However, Babesia spp. has not been reported in pangolins. The aim of the study was to determine the prevalence of Babesia spp. in the Sunda pangolin of Thailand. Materials and Methods: A total of 128 confiscated Sunda pangolins from across different regions in Thailand were investigated. These pangolins had been admitted to a regional Wildlife Quarantine Center for rehabilitation before release in the forest. Routine physical examinations were conducted on the animals. We collected blood samples from each pangolin for hematological analysis and to detect Babesia spp. using polymerase chain reaction (PCR) targeting the partial 18s rRNA gene. Results: Babesia-specific PCR detected 53 animals (41.4%) that were positive for Babesia spp. Blood smears were obtained from the positive samples and investigated under a light microscope to observe for trophozoites of Babesia spp. Examination of 40 PCR-positive and -negative samples found no significant differences between the hematological parameters of Babesia-positive and Babesia-negative samples. Eight PCR-positive samples were randomly selected and their DNA was sequenced. Seven and one of sequences match uncharacterized Babesia spp. with 100% and 99.2% similarity, respectively. Phylogenetic analysis demonstrated that our samples form a unique monophyletic clade along with other Babesia spp. detected in the wild. This clade is clearly separated from other Babesia spp. from small carnivores, ruminants, and rats. Conclusion: Our results provide evidence of infection of Sunda pangolins in Thailand by Babesia spp. These pangolins originated from different regions and had not lived together before blood collection. Thus, we suggest that the uncharacterized Babesia spp. found in this study constitute a new group of pangolin-specific Babesia spp. The prevalence of the uncharacterized Babesia spp. was not correlated to pangolin health. Further studies are required to characterize the genomes and phenotypes, including the morphology and pathogenicity of these protozoa. Such information will be helpful for the conservation and health management of the Sunda pangolin.

Duck Tembusu virus (DTMUV) belongs to the family Flaviviridae and genus Orthoflavivirus. It causes disease in ducks, affecting the nervous system and significantly reducing egg production. The first outbreak of DTMUV in Thailand was reported in 2013, with widespread cases across various regions. However, serological diagnosis of DTMUV is challenging due to antibody cross-reactivity with other flaviviruses. To address this issue, we developed an ELISA based on subviral particles. The cassette encoding the membrane precursor and envelope genes of DTMUV (strain KPS54A61) were cloned into a pCAGGS vector with an OSF-tag and transfected into HEK-293T cells to generate subviral particles. The subviral particles were detected in the supernatant of the transfected cell via immunoblotting using anti-DTMUV E protein and anti-Strep-tag antibodies, which revealed a protein band of approximately 59 kDa. An electron microscopy confirmed the presence of particles approximately 35 nm in diameter. To optimize the SP-based ELISA, checkerboard titration identified the optimal antigen concentration as 70 µg/mL and the optimal serum dilution as 1:100,000. A cut-off value was established for the assay, and testing 300 duck serum samples using the SP-based ELISA identified 41 positive samples (14%) and 259 negative samples (86%). The SP-based ELISA exhibited 100% sensitivity and specificity, achieving a perfect agreement score of 1.0 in comparison with the serum neutralization test. Additionally, specificity testing using antibodies specific to Japanese Encephalitis virus (JEV) revealed no cross-reactivity in the ELISA test. Therefore, the developed SP-based ELISA is highly effective for screening and monitoring DTMUV outbreaks in duck farms, significantly reducing the risk of viral spread and enabling the timely implementation of disease control measures.

Human-to-animal SARS-CoV-2 transmission was observed, including a veterinarian contracting COVID-19 through close contact with an infected cat, suggesting an atypical zoonotic transmission. This study investigated the prevalence of SARS-CoV-2 antibodies in cats during human outbreaks and elucidated the correlation between cat infections and human epidemics. A total of 1107 cat serum samples were collected and screened for SARS-CoV-2 antibodies using a modified indirect ELISA human SARS-CoV-2 antibody detection kit. The samples were confirmed using a cPass™ neutralization test. The SARS-CoV-2 seropositivity rate was 22.67% (199/878), mirroring the trend observed in concomitant human case numbers. The waves of the epidemic and the provinces did not significantly impact ELISA-positive cats. Notably, Chon Buri exhibited a strong positive correlation (r = 0.99, p = 0.009) between positive cat sera and reported human case numbers. Additionally, the cPass™ neutralization test revealed a 3.99% (35/878) seropositivity rate. There were significant differences in numbers and proportions of positive cat sera between epidemic waves. In Samut Sakhon, a positive correlation (r = 1, p = 0.042) was noted between the proportion of positive cat sera and human prevalence. The findings emphasize the need for ongoing surveillance to comprehend SARS-CoV-2 dynamics in both human and feline populations.

Background and Aim: Asthma, a chronic disease affecting humans and animals, has recently become increasingly prevalent and steadily widespread. The alternative treatment of asthma using helminth infections or helminth-derived immunomodulatory molecules (IMs) has been evaluated and demonstrated significant amelioration of disease severity index in vitro and in vivo. Trichinella spiralis, a parasitic nematode and its IMs, elicits a potential to relieve asthma and other immune-related disorders. In this study, we investigated the immunomodulatory function of recombinant T. spiralis novel cystatin (rTsCstN) in ameliorating acute inflammatory asthma disorders in a murine model. Materials and Methods: Female BALB/c mice were sensitized using intraperitoneal injection of ovalbumin (OVA)/alum and subsequently challenged with intranasal administration of OVA alone or OVA + rTsCstN for 3 consecutive days, producing OVA-induced allergic asthma models. To evaluate the therapeutic efficacy of rTsCstN, the inflammatory cells and cytokines in bronchoalveolar lavage fluid (BALF) and OVA-specific immunoglobulin E levels in serum were assessed. Histological alterations in the lung tissues were determined by hematoxylin and eosin (H&E) staining and eventually scored for the extent of inflammatory cell infiltration. Results: The asthmatic mouse models challenged with OVA + rTsCstN demonstrated a significant reduction of eosinophils (p < 0.01), macrophages (p < 0.05), and cytokines tumor necrosis factor-α (p < 0.05) and interferon (IFN)-γ (p < 0.05) in BALF when compared with the mice challenged with OVA alone. However, the levels of interleukin (IL)-4 and IL-10 remained unchanged. Histological examination revealed that mice administered OVA + rTsCstN were less likely to have inflammatory cell infiltration in their perivascular and peribronchial lung tissues than those administered OVA alone. Conclusion: Recombinant T. spiralis novel cystatin demonstrated immunomodulatory effects to reduce severe pathogenic alterations in asthma mouse models, encouraging a viable alternative treatment for asthma and other immunoregulatory disorders in humans and animals in the future. Keywords: asthma, immunomodulatory molecule, recombinant Trichinella spiralis novel cystatin, Trichinella spiralis.

Background and Aim: Trypanosoma evansi is a blood and tissue protozoan parasite affecting domestic and wild animals. The T. evansi Thai strain, namely, T. evansi from dairy cattle number 953 (TEDC 953) strain, has been successfully isolated from dairy cattle and cultivated in vitro. The in vitro-cultivated parasite is useful for biological studies, evaluation of novel chemotherapeutic agents, and production of antigens for diagnostic tests. This study aimed to observe the histopathology and virulence of an in vitro-adapted T. evansi TEDC 953 strain in vivo. Materials and Methods: The histopathology and virulence of the TEDC 953 strain were clarified in mice. Six mice were infected with 1 × 105 trypomastigotes of TEDC 953 strain intraperitoneally, and four mice were in the negative control. Parasitemia was monitored daily, and the mice were euthanized on 30 days post-infection (DPI). Internal organs were collected for histopathological examination using hematoxylin and eosin staining. Results: Histopathological lesions were found in the liver, lung, heart, kidney, spleen, and brain of the inoculated mice. The main histopathological feature was lymphoplasmacytic inflammation in parenchyma and perivascular areas of multiple organs, and the severity of histopathological changes was related to the presence of trypomastigotes in the regional vessels. Granulomatous inflammation was seen in meninges, pleura, renal capsule, renal pelvis, and spleen of some infected mice. Four mice died at 17, 24, 26, and 27 DPI with an average parasitemia of 4.05 × 1011 trypomastigotes/mL. The average survival time was 23.5 DPI (mice = 4). Conclusion: This study confirmed that the TEDC 953 strain is infectious and pathogenic in mice after the continuously cultivated in vitro. To replace the use of experimental animals, the in vitro-cultivated parasite can be used instead in further studies. Keywords: experimentally infected mice, histopathology, in vitro, in vivo, Trypanosoma evansi Thai strain, virulence.

Human-to-animal SARS-CoV-2 transmission was observed, including a veterinarian contracting COVID-19 through close contact with an infected cat, suggesting an atypical anthropozoonotic transmission. This study investigated the prevalence of SARS-CoV-2 antibodies in cats during human outbreaks and elucidated the correlation between cat infections and human epidemics. A total of 1,107 cat sera samples were collected and screened for SARS-CoV-2 antibodies using a modified indirect ELISA human SARS-CoV-2 antibodies detection kit. The samples were confirmed using a cPass surrogate viral neutralization assay. The SARS-CoV-2 seropositivity rate was 22.67% (199/878), mirroring the trend observed in concomitant human case numbers. The waves of an epidemic and provinces did not significantly impact ELISA-positive cat. Notably, Chon Buri ex-hibited a strong positive correlation (r = 0.99, P = 0.009) between positive cat sera and reported human case numbers. Additionally, cPass surrogate viral neutralization revealed a 3.99% (35/878) seropositivity rate. While there were significant differences in positive cat numbers and proportions between epidemic waves. In Samut Sakhon, a positive correlation (r = 1, P = 0.042) was noted between the proportion of positive cat sera and reported human cases. The findings emphasize the need for ongoing surveillance to comprehend SARS-CoV-2 dynamics in both human and feline populations.