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The aim of this study was to analyze the immunogenic response elicited in swine by two synthetic peptides derived from GP5 to understand the role of lineal B epitopes in the humoral and B-cell-mediated response against the porcine reproductive and respiratory syndrome virus (PRRSV). For inoculation, twenty-one-day-old pigs were allocated into six groups: control, vehicle, vaccinated (Ingelvac-PRRSV, MLV®), non-vaccinated and naturally infected, GP5-B and GP5-B3. At 2 days post-immunization (dpi), the GP5-B3 peptide increased the serum concentrations of cytokines associated with activate adaptive cellular immunity, IL-1ß (1.15 ± 1.15 to 10.17 ± 0.94 pg/mL) and IL-12 (323.8 ± 23.3 to 778.5 ± 58.11 pg/mL), compared to the control group. The concentration of IgGs anti-GP5-B increased in both cases at 21 and 42 dpi compared to that at 0 days (128.3 ± 8.34 ng/mL to 231.9 ± 17.82 and 331 ± 14.86 ng/mL), while IgGs anti-GP5-B3 increased at 21 dpi (105.1 ± 19.06 to 178 ± 15.09 ng/mL) and remained at the same level until 42 dpi. Also, antibody-forming/Plasma B cells (CD2+/CD21-) increased in both cases (9.85 ± 0.7% to 13.67 ± 0.44 for GP5-B and 15.72 ± 1.27% for GP5-B3). Furthermore, primed B cells (CD2-/CD21+) from immunized pigs showed an increase in both cases (9.62 ± 1.5% to 24.51 ± 1.3 for GP5-B and 34 ± 2.39% for GP5-B3) at 42 dpi. Conversely the naïve B cells from immunized pigs decreased compared with the control group (8.84 ± 0.63% to 6.25 ± 0.66 for GP5-B and 5.78 ± 0.48% for GP5-B3). Importantly, both GP5-B and GP5-B3 peptides exhibited immunoreactivity against serum antibodies from the vaccinated group, as well as the non-vaccinated and naturally infected group. In conclusion, GP5-B and GP5-B3 peptides elicited immunogenicity mediated by antigen-specific IgGs and B cell activation.

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This study aimed to investigate the immunomodulatory behavior of soluble immune checkpoints (sICPs) and other biomarkers in the pathophysiology of SARS-CoV-2 infection. The study included 59 adult participants, 43 of whom tested positive for SARS-CoV-2. Patients were divided into three cohorts: those with moderate disease (n = 16), recovered patients with severe disease (n = 13), and deceased patients with severe disease (n = 16). In addition, 16 participants were pre-pandemic subjects negative for SARS-CoV-2. The relative activity of neutralizing antibodies (rNAbs) against SARS-CoV-2 and the values of 14 sICPs in peripheral blood were compared between the four groups. Because the increase of markers values of inflammation [NLR > 12; CRP > 150 mg/L] and venous thromboembolism [D-dimer > 0.5 mg/L] has been associated with mortality from COVID-19, the total and differential leukocyte counts, the NLR, and CRP and D-dimer values were obtained in patients with severe disease. No differences in rNAbs were observed between the cohorts. Only the levels of five sICPs, sCD27, sHVEM sTIM-3, sPD-1, and sPDL-1, were significantly higher in patients with severe rather than moderate disease. The sPDL-2 level and NLR were higher in deceased patients than in recovered patients. However, there was no difference in CRP and D-dimer values between the two groups. Of the five soluble biomarkers compared among patients with severe disease, only sPDL-2 was higher in deceased patients than in recovered patients. This suggests that immuno-inhibitory sICPs might be used as indicators for severe COVID-19, with sPDL-2 used to assess individual risk for fatality.IMPORTANCECOVID-19, the disease caused by a SARS-CoV-2 infection, generates a broad spectrum of clinical symptoms, progressing to multiorgan failure in the most severe cases. As activation of the immune system is pivotal to eradicating the virus, future research should focus on identifying reliable biomarkers to efficiently predict the outcome in severe COVID-19 cases. Soluble immune checkpoints represent the function of the immune system and are easily determined in peripheral blood. This research could lead to implementing more effective severity biomarkers for COVID-19, which could increase patients' survival rate and quality of life.

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RESUMEN El estudio buscó describir la etiología y frecuencia bacteriana en los teléfonos celulares del personal de salud en el Hospital de Clínicas de Chiclayo, Perú, de marzo a agosto de 2022. Se analizaron 30 teléfonos de médicos, enfermeros y técnicos en áreas de hospitalización y Unidad de Vigilancia Intensiva (UVI). Se tomaron muestras de las pantallas, se cultivaron y se identificaron las bacterias mediante pruebas bioquímicas. Se registró y analizó la información con Microsoft Excel 2013. El 56,7 % de los teléfonos presentó colonización bacteriana: Gram positivas en 33,3 % y Gram negativas en 23,3 %. Predominaron Staphylococcus coagulasa negativa (35,3 %) y Escherichia coli (23,5 %) en hospitalización, y Staphylococcus aureus (23,5 %) en UVI. El 66,7 % desinfectaba los teléfonos poco y el 40 % lavaba las manos con poca frecuencia. Staphylococcus coagulasa negativa, S. aureus y E. coli fueron los agentes más frecuentes, sugiriendo deficiencias en la higiene hospitalaria

ABSTRACT The study aimed to describe the etiology and bacterial frequency on the cell phones of healthcare personnel at the Hospital de Clínicas de Chiclayo, Peru, from March to August 2022. Thirty phones from doctors, nurses, and technicians in hospitalization areas and the Intensive Vigilance Unit (IVU) were analyzed. Samples were taken from the phone screens, cultured, and bacteria were identified using biochemical tests. The data was recorded and analyzed with Microsoft Excel 2013. Bacterial colonization was found on 56.7% of the phones: Gram-positive bacteria on 33.3% and Gram-negative bacteria on 23.3%. Staphylococcus coagulase-negative (35.3%) and Escherichia coli (23.5%) predominated in hospitalization, while Staphylococcus aureus (23.5%) predominated in the IVU. 66.7% of the personnel rarely disinfected their phones, and 40% washed their hands infrequently. Staphylococcus coagulase-negative, S. aureus, and E. coli were the most frequent agents, suggesting deficiencies in hospital hygiene practices.

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Fastidious endosymbiotic Rickettsiales-like organisms (RLOs) have been observed in the digestive diverticula of the cultured pleasure oyster (Crassostrea corteziensis) from Nayarit, Mexico since 2007. In a few mollusk species, these bacteria have been associated with mortality events and production losses. The type of relationship between the RLOs and the pleasure oyster is largely unknown and further investigations are needed to determine if these bacteria warrant management concern in C. corteziensis. In this study, the morphological characteristics of the RLOs were studied by histology and SEM, and the taxonomic affiliations of the bacteria were evaluated by 16S rRNA amplicon sequencing. In addition, the prevalence and intensity of the RLOs was recorded from 2007 to 2017 by histology. The RLOs were observed inside circular basophilic cytoplasmic membrane bound vacuoles (MBVs) that had an average length and width of 15.70 ± 15.24 µm and 15.42 ± 14.95 µm respectively. Apart from cellular hypertrophy, no tissue alterations were observed in the areas adjacent to the RLOs. Individual bacteria within the MBVs were coccoid in shape with an average length of 0.65 ± 0.12 µm and an average width of 0.38 ± 0.09 µm. The bacterial microbiota of a selected number of samples (one sample without RLOs and two samples with RLOs) showed the presence of intracellular parasite OTUs corresponding to the families Rickettsiaceae and Anaplasmataceae, suggesting that the RLOs from the pleasure oyster is associated with the order Rickettsiales. A mean prevalence of 5 % was observed throughout the study period and the majority of the organisms (89 %) presented low intensity of Grade 1 (30-61 RLOs) of the MBVs. A higher prevalence of the RLOs was observed during warmer months. The lack of tissue alterations, the low prevalence and the low intensity of the MBVs suggest that the RLOs from C. corteziensis is a commensal endosymbiont that presents little risk for oyster production in Nayarit, México. However, regular monitoring is needed to detect if any variation in this relationship occurs, mainly in a scenario where extreme environmental fluctuations may occur.

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Several PCR methodologies are available for the detection of Enterocytozoon hepatopenaei (EHP) that target the SSU rRNA gene. However, these methodologies are reported as unsuitable for the detection of EHP due to specificity issues. Here, we report the applicability of two commonly used SSU rRNA methodologies for the detection of additional microsporidia from the genus Vittaforma that is present in cultured Penaeus vannamei from Costa Rica. The molecular detection of DNA of the novel microsporidia can only be achieved using SSU rRNA targeting methodologies and does not cross-react with the highly specific spore wall protein gene PCR detection method.

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We analyzed the T-cell responses induced by lineal epitopes of glycoprotein 5 (GP5) from PRRSV to explore the role of this protein in the immunological protection mediated by T-cells. The GP5 peptides were conjugated with a carrier protein for primary immunization and booster doses. Twenty-one-day-old pigs were allocated into four groups (seven pigs per group): control (PBS), vehicle (carrier), PTC1, and PTC2. Cytokine levels were measured at 2 days post-immunization (DPI) from serum samples. Cytotoxic T-lymphocytes (CTLs, CD8+) from peripheral blood were quantified via flow cytometry at 42 DPI. The cytotoxicity was evaluated by co-culturing primed lymphocytes with PRRSV derived from an infectious clone. The PTC2 peptide increased the serum concentrations of pro-inflammatory cytokines (i.e., TNF-α, IL-1ß, IL-8) and cytokines that activate the adaptive cellular immunity associated with T-lymphocytes (i.e., IL-4, IL-6, IL-10, and IL-12). The concentration of CTLs (CD8+) was significantly higher in groups immunized with the peptides, which suggests a proliferative response in this cell population. Primed CTLs from immunized pigs showed cytolytic activity in PRRSV-infected cells in vitro. PTC1 and PTC2 peptides induced a protective T-cell-mediated response in pigs immunized against PRRSV, due to the presence of T epitopes in their sequences.

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The emergence and spread of disease-causing viruses in shrimp aquaculture is not uncommon. Since 2016, unusual mortalities have been affecting the Brazilian shrimp industry and we have associated these unusual mortalities with a novel variant of infectious myonecrosis virus (IMNV). The transcriptome analysis of these diseased shrimp showed an additional divergent viral sequence that we have assigned to the family Solinviviridae. The novel virus has been tentatively termed Penaeus vannamei solinvivirus (PvSV) (GenBank accession: OP265432). The full-length genome of the PvSV is 10.44 kb (excluding the poly A tail) and codes for a polyprotein of 3326 aa. Five conserved domains coding for a helicase, RdRp, calicivirus coat protein, G-patch and tegument protein were identified. The genome organization of the PvSV is similar to other (Nylan deria fulva virus 1) solinvivirus. A unique feature of this virus that differs from other members of the Solinviviridae is the presence of putative nuclear localization signals. The tissue tropism of this virus is wide, infecting cells of the hepatopancreas, gastrointestinal tract, lymphoid organ and muscle tissue. Another unique feature is that it is the only RNA virus of penaeid shrimp that shows a nuclear localization by in situ hybridization. The PvSV has a wide distribution in Brazil and has been found in the states of Maranhão State (Perizes de Baixo), Piaui State (Mexeriqueira), Ceará State (Camocim, Jaguaruana, Aracati and Alto Santo) and Pará State where it has been detected in coinfections with IMNV. The diagnostic methods developed here (real-time RT-PCR and in situ hybridization) are effective for the detection of the pathogen and should be employed to limit its spread. Furthermore, the identification of the PvSV shows the increasing host range of the relatively new family Solinviviridae.

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INTRODUCCIÓN: La aparición y diseminación de Enterobacterales resistentes a carbapenémicos ha generado un gran impacto en las infecciones asociadas a la atención de salud en el mundo. Recientemente, en Chile se detectó un brote por Klebsiella pneumoniae productora de carbapenemasas tipo oxacilinasas (OXA) de la subfamilia tipo OXA-48, reportándose los primeros casos en pacientes hospitalizados mayoritariamente en la zona norte del país. OBJETIVO: Determinar los perfiles fenotípicos, genotípicos y de susceptibilidad antimicrobiana de 16 cepas referidas durante mayo del año 2021 desde las regiones de Antofagasta y Metropolitana al Laboratorio de Referencia del Instituto de Salud Pública. METODOLOGÍA: Las cepas provenientes de muestras clínicas fueron analizadas mediante técnicas tradicionales (Kirby-Bauer y epsilometría) y automatizadas, además de técnicas colorimétricas, inmunocromatográficas y moleculares (RPC y PFGE). Resultados: Se detectó la presencia de los genes blaoxa-48 y blaoxa-232 con una resistencia inusual, tanto a carbapenémicos (ertapenem, imipenem y meropenem) como a cefalosporinas (cefepime, cefotaxima y ceftazidima), además de piperacilina/tazobactam y temocilina. Se detectaron dos subtipos por PFGE, siendo predominante el clon CL-Kpn-Spe-329 (93,8%) con dos mecanismos de resistencia identificados: carbapenemasa y β-lactamasa de espectro extendido (BLEE). CONCLUSIÓN: Ante esta alerta epidemiológica es necesario unificar criterios existentes en la red asistencial nacional para la oportuna detección, vigilancia y control de posibles brotes de cepas productores de oxacilinasa tipo OXA-48.

BACKGROUND: The appearance and spread of carbapenems-resistant Enterobacterales have generated a major impact on health care-associated infections worldwide. Recently, a Klebsiella pneumoniae outbreak expressing OXA-48 like-carbapenemases was detected in Chile, the first reported cases corresponded to hospitalized patients mainly from northern Chile. AIM: To characterize the phenotypic and genotypic profiles of antimicrobial susceptibility of 16 clinical isolates referred during May 2021 from Antofagasta and Metropolitan regions to the Reference Laboratory of Instituto de Salud Publica. METHODS: Antimicrobial susceptibility of all strains was analyzed using traditional (Kirby-Bauer and epsilometry) and automated methods, and complemented with colorimetric, immunochromatographic and molecular (PCR and PFGE) techniques. RESULTS: As a result of the genetic characterization, blaoxa-48 and blaoxa-232 genes were detected, showing the isolates an unusual resistance profile to both carbapenems (ertapenem, imipenem, and meropenem) and cephalosporins (cefepime, cefotaxime, and ceftazidine), as well as piperacillin/ tazobactam and temocillin. Two subtypes were detected by PFGE, with a predominant clone CL-Kpn-Spe-329 (93.8%), with two resistance mechanisms identified: carbapenemase and extended-spectrum β-lactamase (ESBL). CONCLUSION: Due to this epidemiological alert, it is essential the establishment of national guidelines for early detection, surveillance, and control of future outbreaks of OXA-48 like carbapenemases isolates.

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Infection with infectious hypodermal and hematopoietic necrosis virus (IHHNV) is a crustacean disease that caused large-scale mortality in Penaeus stylirostris, deformity and growth retardation in Penaeus vannamei and Penaeus monodon. We surveyed the presence of IHHNV in three major shrimp-producing regions in Ecuador, namely Guayas, El Oro, and Esmeralda. The data show that IHHNV is endemic (3.3-100% prevalence) to shrimp farms in these regions. The whole genome sequences of representative circulating IHHNV genotypes in Ecuador and Peru showed that these genotypes formed a separate cluster within the Type II genotypes and were divergent from other geographical isolates of IHHNV originating in Asia, Africa, Australia, and Brazil. In experimental bioassays using specific pathogen-free (SPF) P. vannamei, P. monodon, and P. stylirostris and representative IHHNV isolates from Ecuador and Peru, the virus did not cause any mortality or induce clinical signs in any of the three penaeid species. Although IHHNV-specific Cowdry type A inclusion bodies were histologically detected in experimentally challenged P. vannamei and P. monodon and confirmed by in situ hybridization, no such inclusions were observed in P. stylirostris. Moreover, P. vannamei had the highest viral load, followed by P. monodon and P. stylirostris. Based on IHHNV surveillance data, we conclude that the currently farmed P. vannamei lines in Ecuador are tolerant to circulating IHHNV genotypes. The genome sequence and experimental bioassay data showed that, although the currently circulating genotypes are infectious, they do not induce clinical lesions in the three commercially important penaeid species. These findings suggest a potentially evolving virus-host relationship where circulating genotypes of IHHNV co-exist in equilibrium with P. vannamei raised in Peru and Ecuador.

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The microsporidian Enterocytozoon hepatopenaei (EHP) is an emerging pathogen that causes substantial economic losses in shrimp (Penaeus spp.) aquaculture worldwide. To prevent diseases in shrimp, the manipulation of the gut microbiota has been suggested. However, prior knowledge of the host-microbiome is necessary. We assessed the modulation of the microbiome (bacteria/fungi) and its predicted functions over the course of disease progression in shrimp experimentally challenged with EHP for 30 days using high throughput 16S rRNA and ITS amplicon sequencing. Infection grade was assessed for the first time by quantitative digital histopathology. According to the infection intensity, three disease-stages (early/developmental/late) were registered. During the early-stage, EHP was not consistently detected, and a high diversity of potentially beneficial microorganisms related to nutrient assimilation were found. In the development-stage, most of the shrimp start to register a high infection intensity related to a decrease in beneficial microorganisms and an increase in opportunistic/pathogenic fungi. During late-stage, animals displayed different infection intensities, showed a displacement of beneficial microorganisms by opportunistic/pathogenic bacteria and fungi related to pathogen infection processes and depletion of energetic reserves. The degenerative cyclic pattern of EHP infection and its effects on beneficial microorganisms and beneficial functions of the shrimp hepatopancreas microbiome are discussed.

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