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Background: Wastewater pathogen monitoring is useful for surveillance of enteric pathogens. Information about the presence of Paslahepevirus balayani (HEV) and emergent Rocahepevirus ratti (RHEV) in untreated water and their correlation with clinical cases is scarce. Aim To longitudinally monitor HEV and RHEV in wastewater and to evaluate their possible correlation with human cases., Methods: This study was carried out in the city of Cordoba (southern Spain) from March 2021 to March 2023. HEV and RHEV occurrence were evaluated by PCR in three sample types: i) sera from patients with acute hepatitis attended at the reference hospital, ii) liver and faeces from urban rodents, and iii) grab sewage samples collected weekly from the municipal wastewater treatment plant., Results: We analysed 106 untreated wastewater samples, 304 individuals with acute hepatitis, and 20 rodents. HEV and RHEV were detected in only one (0.9 %) and almost all samples (94.3 %) of wastewater samples, respectively. A total of 22 cases of acute HEV infection (7.2 %) and two cases of RHEV (0.7 %) were detected from all acute hepatitis cases observed. Only RHEV was found in rodents, with a positive frequency of 55 %. The presence of HEV in wastewater coincided with the detection of one case in which the same HEV genotype was isolated. A concentration of HEV clinical cases between June and July of 2022 was observed but not detected in water. Both RHEV clinical cases were detected in summer 2022, but no correlation was found with wastewater detection., Conclusions: Our study shows that there is no correlation between clinical cases and wastewater detection of HEV or RHEV., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Previous studies have shown that activation of effector caspase-3 is associated with the apoptosis of lymphocytes occurring during infection with bovine viral diarrhoea virus (BVDV); however, the regulation of the apoptosis pathways that induce cell death via activation of effector caspase-3 has not yet been clarified. The aim of this study was to examine immunohistochemically the expression of cleaved caspase (CCasp)-8 (initiator caspase of the extrinsic pathway), CCasp9 (initiator caspase of the intrinsic pathway) and Bcl-2 (an anti-apoptotic marker) in gut-associated lymphoid tissue (GALT) of the ileum from calves inoculated with a non-cytopathic strain of BVDV genotype-1. CCasp8 had similar expression to that of CCasp3. In interfollicular T-cell areas there was moderate apoptosis and evidence of moderate activation of initiator caspase-8. In B-cell follicles there was marked lymphocyte apoptosis and evidence of intense caspase-8 activation, highlighting the potentially major role of the extrinsic pathway in lymphocyte apoptosis in the GALT during BVDV infection. Additionally, there was a significant decrease in the number of CCasp9(+) cells from the start of the experiment and this was linked to inactivation of caspase-9. Therefore, the intrinsic pathway may play only a minor role in the induction of lymphocyte apoptosis. Finally, the observed overexpression of Bcl-2 protein could play a major role in protecting lymphocytes in the T-cell areas against apoptosis, while low levels of Bcl-2 expression could be associated with the follicular lymphocyte apoptosis occurring during BVDV infection., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The VP7 structural protein is the most abundant of the major core proteins and is highly conserved in all serotypes of bluetongue virus (BTV). The aim of this study was to develop immunohistochemical techniques for the detection of BTV VP7 in Bouin's- and formalin-fixed and paraffin wax-embedded tissues from small ruminants (sheep and goats) naturally infected with BTV. Tissue samples were taken from animals in which BTV infection had been confirmed by reverse transcriptase polymerase chain reaction. Optimal results were obtained by incubation of monoclonal antibody 2E9 on samples fixed with Bouin's solution or neutral buffered formalin. Optimum antigen retrieval for Bouin's-fixed samples was by microwave heating (6 min) of tissue samples in citrate buffer (pH 6.0, 0.01 M), while for formalin-fixed samples a 30 min heating period in pH 9.0 buffer was required. In both species, BTV was mainly detected in the spleen, lymph nodes and lungs; specifically within the arteriolar and capillary endothelial cells, together with macrophages and lymphocytes. The immunohistochemical method described will be a useful tool for future research., ((c) 2010 Elsevier Ltd. All rights reserved.)

Eight colostrum-deprived calves were inoculated intranasally with a non-cytopathic strain of bovine viral diarrhoea virus (BVDV) genotype-1 and killed in batches of two at 3, 6, 9 and 14 days post-inoculation (dpi). Two non-inoculated animals with similar background served as controls. All infected calves developed mild pyrexia and transient leucopenia due primarily to lymphopenia. Viraemia was correlated with body temperature and inversely related to leucocyte count. Ileal Peyer's patches developed mild follicular lymphoid depletion from 3dpi. This change was accompanied by cellular fragmentation and pyknosis, characteristic of apoptosis, which was most prominent from 6dpi. Lymphocyte apoptosis was confirmed by ultrastructural examination. Stellate cells and macrophages located in the lymphoid follicles were identified as infected by virus from 3dpi and the number of these infected cells increased until 9dpi. Fewer lymphocytes expressed BVDV antigen. Macrophages had morphological features consistent with activation of secretory and phagocytic function from 3dpi. These findings suggest that BVDV is only directly responsible for the destruction of a small number of lymphocytes. Although lymphocyte infection coincided with the onset of apoptosis, the intensity of infection was disproportionate to the marked depletion of gut-associated lymphoid tissue, particularly during the early stages of this process. Characterization of the indirect pathogenic mechanisms involved in the lymphoid depletion associated with BVDV infection will require additional study.