Immunologic mediators profile in COVID-19 convalescence.

SARS-CoV-2 caused the pandemic situation experienced since the beginning of 2020, and many countries faced the rapid spread and severe form of the disease. Mechanisms of interaction between the virus and the host were observed during acute phase, but few data are available when related to immunity dynamics in convalescents. We conducted a longitudinal study, with 51 healthy donors and 62 COVID-19 convalescent patients, which these had a 2-month follow-up after symptoms recovery. Venous blood sample was obtained from all participants to measure blood count, subpopulations of monocytes, lymphocytes, natural killer cells and dendritic cells. Serum was used to measure cytokines, chemokines, growth factors, anti-N IgG and anti-S IgG/IgM antibodies. Statistic was performed by Kruskal-Wallis test, and linear regression with days post symptoms and antibody titers. All analysis had confidence interval of 95%. Less than 35% of convalescents were anti-S IgM+, while more than 80% were IgG+ in D30. Anti-N IgG decreased along time, with loss of seroreactivity of 13%. Eosinophil count played a distinct role on both antibodies during all study, and the convalescence was orchestrated by higher neutrophil-to-lymphocyte ratio and IL-15, but initial stages were marked by increase in myeloid DCs, B1 lymphocytes, inflammatory and patrolling monocytes, G-CSF and IL-2. Later convalescence seemed to change to cytotoxicity mediated by T lymphocytes, plasmacytoid DCs, VEGF, IL-9 and CXCL10. Anti-S IgG antibodies showed the longest perseverance and may be a better option for diagnosis. The inflammatory pattern is yet present on initial stage of convalescence, but quickly shifts to a reparative dynamic. Meanwhile eosinophils seem to play a role on anti-N levels in convalescence, although may not be the major causative agent. We must highlight the importance of immunological markers on acute clinical outcomes, but their comprehension to potentialize adaptive system must be explored to improve immunizations and further preventive policies.

Immunological and homeostatic pathways of alpha -1 antitrypsin: a new therapeutic potential.

α -1 antitrypsin (A1AT) is a 52 kDa acute-phase glycoprotein belonging to the serine protease inhibitor superfamily (SERPIN). It is primarily synthesized by hepatocytes and to a lesser extent by monocytes, macrophages, intestinal epithelial cells, and bronchial epithelial cells. A1AT is encoded by SERPINA1 locus, also known as PI locus, highly polymorphic with at least 100 allelic variants described and responsible for different A1AT serum levels and function. A1AT inhibits a variety of serine proteinases, but its main target is represented by Neutrophil Elastase (NE). However, recent attention has been directed towards its immune-regulatory and homeostatic activities. A1AT exerts immune-regulatory effects on different cell types involved in innate and adaptive immunity. Additionally, it plays a role in metal and lipid metabolism, contributing to homeostasis. An adequate comprehension of these mechanisms could support the use of A1AT augmentation therapy in many disorders characterized by a chronic immune response. The aim of this review is to provide an up-to-date understanding of the molecular mechanisms and regulatory pathways responsible for immune-regulatory and homeostatic activities of A1AT. This knowledge aims to support the use of A1AT in therapeutic applications. Furthermore, the review summarizes the current state of knowledge regarding the application of A1AT in clinical and laboratory settings human and animal models.

Molecular mechanism of autophagy in porcine reproductive and respiratory syndrome virus infection.

Porcine reproductive and respiratory syndrome virus (PRRSV), a significant pathogen affecting the swine industry globally, has been shown to manipulate host cell processes, including autophagy, to facilitate its replication and survival within the host. Autophagy, an intracellular degradation process crucial for maintaining cellular homeostasis, can be hijacked by viruses for their own benefit. During PRRSV infection, autophagy plays a complex role, both as a defense mechanism of the host and as a tool exploited by the virus. This review explores the current understanding of the molecular mechanisms underlying autophagy induction under PRRSV infection, its impact on virus replication, and the potential implications for viral pathogenesis and antiviral strategies. By synthesizing the latest research findings, this article aims to enhance our understanding of the intricate relationship between autophagy and PRRSV, paving the way for novel therapeutic approaches against this swine pathogen.

Virucidal effects of eucalyptus essential oil on porcine reproductive and respiratory syndrome virus.

Currently, the efficacy of vaccination for preventing and controlling PRRSV is insufficient. Therefore, there is an urgent need for novel effective preventive strategies. This study aimed to investigate the antiviral effect of Eucalyptus essential oil (EEO) against PRRSV in vitro. Marc-145 cells were infected with PRRSV (rJXA1-R), and the toxicity of EEO in the cells was measured using the Cell Counting Kit-8 method. Additionally, the antiviral effect of EEO on PRRSV-infected cells was assessed using three treatment methods: drug administration post-PRRSV inoculation (post-treatment), drug administration before PRRSV inoculation (pre-treatment), and simultaneous drug administration and PRRSV inoculation (co-treatment). The EEO could not inhibit virus adsorption and/or replication since post-treatment and pre-treatment did not prevent viral infectivity. However, EEO exerted a significant virucidal effect on PRRSV. When PRRSV-infected cells were treated with 0.0156, 0.0312, and 0.0625% EEO, the cell survival rates were 55.37, 118.96, and 121.67%, respectively, and the titer of progeny virions decreased from 5.77 Log10TCID50 to 5.21 Log10TCID50, 0.55 Log10TCID50, and less than 0.167 Log10TCID50, respectively (where TCID50 is the 50% tissue culture infected dose). The fluorescence intensity of the PRRSV N protein significantly decreased in the indirect immunofluorescence assay. When cells were co-treated with EEO (0.0625%) and PRRSV (1000 TCID50) for 15 min, the viral particles were inactivated, and PRRSV (1000 TCID50) particles loss infectivity when the co-treatment time reached 60 min. In a word, EEO has no obvious therapeutic effect on PRRSV infection, but it can effectively inactivate virus particles and make them lose the ability to infect cells. These findings provide insights for the development and use of EEO to treat PRRS.

Repurposing existing drugs for the treatment ofCOVID-19/SARS-CoV-2: A review of pharmacological effects and mechanism of action.

Following the coronavirus disease-2019 outbreak caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), there is an ongoing need to seek drugs that target COVID-19. First off, novel drugs have a long development cycle, high investment cost, and are high risk. Second, novel drugs must be evaluated for activity, efficacy, safety, and metabolic performance, contributing to the development cycle, investment cost, and risk. We searched the Cochrane COVID-19 Study Register (including PubMed, Embase, CENTRAL, ClinicalTrials.gov, WHO ICTRP, and medRxiv), Web of Science (Science Citation Index, Emerging Citation Index), and WHO COVID-19 Coronaviral Disease Global Literature to identify completed and ongoing studies as of February 20, 2024. We evaluated the pharmacological effects, in vivo and in vitro data of the 16 candidates in the paper. The difficulty of studying these candidates in clinical trials involving COVID-19 patients, dosage of repurposed drugs, etc. is discussed in detail. Ultimately, Metformin is more suitable for prophylactic administration or mildly ill patients; the combination of Oseltamivir, Tamoxifen, and Dexamethasone is suitable for moderately and severely ill patients; and more clinical trials are needed for Azvudine, Ribavirin, Colchicine, and Cepharanthine to demonstrate efficacy.

Assistance time and peripheral oxygen saturation in prehospital emergency data as predictors of COVID19 hospital outcomes.

To verify if data obtained in the prehospital evaluation of patients with severe acute respiratory syndrome (SARS) during the initial response to the COVID-19 pandemic is associated with clinical outcomes: mechanical ventilation, hospital discharge, and death. This is a retrospective analysis involving secondary data from the Emergency Medical Service (EMS) records and the Health Surveillance Information System of patients assisted by the EMS in Manaus, from January to June 2020, the period of the first peak of COVID-19 cases. The combination of the two databases yielded a total of 1.190 patients, who received a first EMS response and were later admitted to hospital with SARS and had data on clinical outcomes of interest available. Patients were predominantly male (754, 63.4%), with a median age of 66 (IQR: 54.0-78.0) years. SARS illness before medical assistance was associated to need for invasive mechanical ventilation (IMV, p < 0.001). Lower pre-hospital SpO2 was associated to death (p = 0.025). Death was more common among patients with respiratory support needs, especially in the invasive ventilation group (262/287; 91.3%) (p < 0.001). In addition, IMV was more common among elderly individuals (p < 0.001). Patients admitted to ICU had a greater chance of dying when compared to non-ICU admitted patients (p < 0.001), and closely related to IMV (p < 0.001). Patients in ICU were also older (p = 0.003) and had longer hospital stay (p < 0.001). Mortality was associated with mechanical ventilation (p < 0.001), ICU admission (p < 0.001), and older age (p < 0.001). Patients who died had a shorter length of both ICU and total hospital stay (p < 0.001). Prehospital EMS may provide feasible and early recognition of critical patients with SARS in strained healthcare systems, such as in low-resource settings and pandemics.

Understanding how methyltransferase-like 3 functions in lung diseases: From pathogenesis to clinical application.

Lung diseases have complex pathogenesis and treatment challenges, showing an obvious increase in the rate of diagnosis and death every year. Therefore, elucidating the mechanism for their pathogenesis and treatment ineffective from novel views is essential and urgent. Methyltransferase-like 3 (METTL3) is a novel post-transcriptional regulator for gene expression that has been implicated in regulating lung diseases, including that observed in chronic conditions such as pulmonary fibrosis (PF), pulmonary arterial hypertension (PAH), and chronic obstructive pulmonary disease (COPD), as well as acute conditions such as pneumonia, severe acute respiratory syndrome coronavirus 2 infection, and sepsis-induced acute respiratory distress syndrome. Notably, a comprehensive summary and analysis of findings from these studies might help understand lung diseases from the novel view of METTL3-regulated mechanism, however, such a review is still lacking. Therefore, this review aims to bridge such shortage by summarising the roles of METTL3 in lung diseases, establishing their interrelationships, and elucidating the potential applications of METTL3 regarding diagnosis, treatment, and prognosis. The analysis collectively suggests METTL3 is contributable to the onset and progression of these lung diseases, thereby prospecting METTL3 as a valuable biomarker for their diagnosis, treatment, and prognosis. In conclusion, this review offers elucidation into the correlation between METTL3 and lung diseases in both research and clinical settings and highlights potential avenues for exploring the roles of METTL3 in the respiratory system.

Effectiveness of Paxlovid in the treatment of the SARS-CoV-2 Omicron variant infection in children with hematologic malignancies: a retrospective cohort study.

Background: Patients with hematologic malignancies (HMs) may be immunocompromised after receiving anti-tumor therapy. Those who also have the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infection face many challenges, including a lack of effective antiviral drugs. This study aimed to investigate the clinical features of the SARS-CoV-2 Omicron variant infection in children with HMs, and the effectiveness of Paxlovid. Methods: A retrospective, non-randomized study was conducted on pediatric patients with HMs infected with the SARS-CoV-2 Omicron variant who had been admitted to the Shanghai Children's Medical Center, Shanghai, China from December 1, 2022 to March 1, 2023. The Paxlovid-treated group (Group P) comprised 21 patients, and the non-Paxlovid-treated group (Group N) comprised 21 patients. The patients' demographic data, clinical features, and therapeutic outcomes were collected. Statistical tests were used to evaluate the effectiveness of the treatment and related factors. Results: The clinical course of the SARS-CoV-2 Omicron variant infection for most of the children with HMs was non-severe (97.6%), and only one child progressed to severe disease (2.4%). The most common symptoms were fever (66.7%) and cough (52.4%). Compared with the children in Group N, those in Group P had worse clinical characteristics, including those who previously underwent hematopoietic stem cell transplantation (HSCT) or chimeric antigen receptor T (CAR-T) cell treatment (71.4% vs. 28.6%, P=0.005), and those in the myelosuppressive phase (57.1% vs. 4.8%, P<0.001). Most of the children in Group P were treated with more than two types of antibiotics (76.2% vs. 42.9%, P=0.02). The patients treated with Paxlovid within 5 days of diagnosis had a median viral clearance time of 5 days [interquartile range (IQR), 4-8 days], which was significantly shorter than that of the patients who were not treated with Paxlovid (P=0.03). There were no significant differences in the clinical outcomes between the two groups after the propensity score matching (PSM) analyses. Eight patients (19%) had repeat-positive (re-positive) test results. No factor was found to be statistically significant in predicting re-positive test results based on the binary logistic regression analysis. Conclusions: Administering Paxlovid within 5 days of the diagnosis of the SARS-CoV-2 Omicron variant infection in children may effectively shorten the clearance time of the virus, but there is still the possibility the patients may have re-positive test results.

Intervention strategies targeting virus and host factors against porcine reproductive and respiratory syndrome virus: A systematic review.

Porcine reproductive and respiratory syndrome (PRRS) caused by porcine reproductive and respiratory syndrome virus (PRRSV) causes considerable economic losses to the global swine industry every year and seriously hinders the healthy development of this industry. Although tremendous efforts have been made over the past 30 years toward the development of prevention and control strategies against PRRSV infection, to date, treatments with proven efficacy have yet to be available due to our incomplete understanding of the molecular basis and complexity of the infection machinery. This review systematically discusses recent advances in the research and development of anti-PRRSV therapies targeting different stages of the viral life cycle. Furthermore, this review puts forward novel intervention targets and research approaches based on our in-depth exploration of virus-host interactions and the latest biological technologies, which have the potential to complement or transform current anti-PRRSV strategies and become breakthrough points for the control of PRRS in the future.

Manifestations of COVID-19 in the posterior eye segment - Up-to-date.

Since coronavirus disease infection-19 (COVID-19) entry to the cells is angiotensin enzyme receptor (ACEII) dependent, extrapulmonary manifestations have been suspected. Ocular manifestations reported in several studies to involve the anterior as well as posterior eye segments. However, the predominance of the anterior eye segment reduced the attention of the scientific community on the posterior eye segment. Our results showed that the incidence of changes in the posterior eye segment is 1/5 of the anterior eye segment. Posterior eye segment manifestations include acute macular neuroretinopathy and paracentral middle maculopathy, central retinal vein/artery occlusion, reactivation of previous uveitis, varicella zoster virus-related acute retinal necrosis in an immunocompromised patient, chorioretinitis, macular hemorrhage, paracentral acute middle maculopathy, retinal detachment, and vitritis with outer retinal abnormalities. The pathogenesis of posterior eye segment manifestations under COVID-19 includes viremia, autoimmune vasculitis, hyperimmune response, coagulopathy, and cytokine storm. A full ophthalmological examination is crucial for patients recovering from COVID-19. The paper provided up-to-date manifestations with potential underlying pathophysiological mechanisms of development, as well as pathogenetic therapy.

Knock down of transforming growth factor beta improves expressions of co-stimulatory molecules, type I interferon-regulated genes, and pro-inflammatory cytokine in PRRSV-inoculated monocyte-derived macrophages.

Porcine reproductive and respiratory syndrome virus (PRRSV) induces a poor innate immune response following infection. This study evaluates the effects of transforming growth factor beta 1 (TGFß1) up-regulated by PRRSV on gene expressions of co-stimulatory molecules, type I interferon (IFN), type I IFN-regulated genes (IRGs), pattern recognition receptors, and pro-inflammatory cytokines in PRRSV-inoculated monocyte-derived macrophages (MDMs). Phosphorothioate-modified antisense oligodeoxynucleotides (AS ODNs) specific to various regions of porcine TGFß1 mRNA were synthesized, and those specific to the AUG region efficiently knockdown TGFß1 mRNA expression and protein translation. Transfection of TGFßAS ODNs in MDMs inoculated with either classical PRRSV-2 (cPRRSV-2) or highly pathogenic PRRSV-2 (HP-PRRSV-2) significantly reduced TGFß1 mRNA expression and significantly increased mRNA expressions of CD80, CD86, IFNß, IRGs (i.e. IFN regulatory factor 3 (IRF3), IRF7, myxovirus resistance 1, osteopontin, and stimulator of IFN genes), Toll-like receptor 3, and tumor necrosis factor-alpha. Transfection of TGFßAS ODNs in MDMs inoculated with HP-PRRSV-2 also significantly increased mRNA expressions of IFNα, IFNγ, and 2'-5'-oligoadenylate synthetase 1. The quantity of PRRSV-2 RNA copy numbers was significantly reduced in MDMs transfected with TGFßAS ODNs as compared to untransfected MDMs. Recombinant porcine TGFß1 (rTGFß1) and recombinant porcine IFNα (rIFNα) sustained and reduced the yields of PRRSV-2 RNA copy numbers in PRRSV-2 inoculated MDMs, respectively. These findings demonstrate a strategy of PRRSV for innate immune suppression via an induction of TGFß expression. These findings also suggest TGFß as a potential parameter that future PRRSV vaccine and vaccine adjuvant candidates should take into consideration.

Engineering a NanoBiT biosensor for detecting angiotensin-converting enzyme-2 (hACE2) interaction with SARS-CoV-2 spike protein and screening the inhibitors to block hACE2 and spike interaction.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is facilitated by its trimeric surface spike protein, which binds to the human angiotensin-converting enzyme 2 (hACE2) receptor. This critical interaction facilitates viral entry and is a primary target for therapeutic intervention against COVID-19. However, it is difficult to fully optimize viral infection using existing protein-protein interaction methods. Herein, we introduce a nano-luciferase binary technology (NanoBiT)-based pseudoviral sensor designed to stimulate the dynamics of viral infection in both living cells and animals. Infection progression can be dynamically visualized via a rapid increase in luminescence within 3 h using an in vivo imaging system (IVIS). Inhibition of viral infection by baicalein and baicalin was evaluated using a NanoBiT-based pseudoviral sensor. These results indicate that the inhibitory efficacy of baicalein was strengthened by targeting the spike protein, whereas baicalin targeted the hACE2 protein. Additionally, under optimized conditions, baicalein and baicalin provided a synergistic combination to inhibit pseudoviral infection. Live bioluminescence imaging was used to evaluate the in vivo effects of baicalein and baicalin treatment on LgBiT-hACE2 mice infected with the BA.2-SmBiT spike pseudovirus. This innovative bioluminescent system functions as a sensitive and early-stage quantitative viral transduction in vitro and in vivo. This platform provides novel opportunities for studying the molecular biology of animal models.

Curing of chronic hepatitis C combined with coronavirus disease 2019 in a couple over 85 years old: a case series study.

Introduction: Data on the management of patients aged more than 85 years with chronic hepatitis C virus (HCV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequential infections are lacking. Methods: The current study described the management of an older couple aged more than 85 years with these above-mentioned two diseases treated with 12 weeks of sofosbuvir/velpatasvir (Epclusa®) and 5 days of nirmatrelvir/ritonavir (Paxlovid®) sequentially. The effectiveness and safety profiles were closely monitored during therapy and till 9 months posttreatment. Results: In late March 2023, the husband with the main complaint of repeated gingival bleeding and asymptomatic wife were 86 and 85 years old, and had HCV RNA levels of 91,800 and 6,630,000 IU/mL, respectively. On the fourth day of sofosbuvir/velpatasvir treatment, the husband had a moderate headache, and the wife had severe headache and moderate fever and dizziness. We then found that their SARS-CoV-2 test results were positive. After careful consideration, the expert panel decided to treat the couple with oral nirmatrelvir/ritonavir (300 mg/100 mg, twice daily) beginning on the fifth day of sofosbuvir/velpatasvir treatment for 5 days. During the 5 days of nirmatrelvir/ritonavir treatment, the patient's symptoms and signs gradually improved, and the patient was negative for SARS-CoV-2 RNA on the fifth day of nirmatrelvir/ritonavir therapy. Meanwhile, the husband's HCV RNA was not detectable after one week of sofosbuvir/velpatasvir treatment till posttreatment month 9, and his ALT level was normal beginning at week 1 of sofosbuvir/velpatasvir treatment. Moreover, the wife's HCV RNA was not detectable after week 4 of sofosbuvir/velpatasvir treatment till posttreatment month 9. Notably, no other symptoms or signs occurred during the treatment or follow-up period, and other serum biochemical parameters remained stable until 9 months after the discontinuation of sofosbuvir/velpatasvir treatment. Conclusion: The older couple aged more than 85 years with chronic HCV and SARS-CoV-2 sequential infection were safely cured by the sofosbuvir/velpatasvir and nirmatrelvir/ritonavir sequential treatment. Discussion: This study suggested that old age should not be a barrier to HCV/SARS-CoV-2 treatment. Given that the proportion of older HCV-infected patients is increasing, clinical trials of direct-acting antiviral agents should include older HCV-infected individuals.

Incidence and Clinical Characteristics of COVID-19 Ophthalmopathy Following the Termination of Dynamic Zero COVID-19 Strategy in China.

Ocular involvement is not uncommon in patients with COVID-19. However, the incidence of COVID-19 ophthalmopathy in COVID-19 patients is still not clear. In this prospective case series study, we recruited 2445 consecutive cases presenting at Neuro-ophthalmology clinic of our Eye Center during the last resurgence of SARS-CoV-2 infection from 8 December 2022 to 15 March 2023 in China, 149 cases were diagnosed as COVID-19 ophthalmopathy, 87 cases were female, with a mean age of 43.2 years, and the mean follow-up time was 15.4 weeks. One hundred and twenty of 149 cases suffered from systemic symptoms mostly manifesting as fever, cough and muscle pain prior to or soon after ocular involvement. The most common COVID-19 ophthalmopathy was optic neuritis (51/149), followed by acute zonal occult outer retinopathy complex disease (31/149), uveitis (17/149), ocular mobility disorder-related (third, fourth, or sixth) cranial nerve neuritis (15/149), anterior ischaemic optic neuropathy (9/149), retinal artery occlusion (8/149), retinal microangiopathy including retinal haemorrhage and cotton wool spot (8/149), viral conjunctivitis (7/149), retinal vein occlusion (3/149), viral keratitis (2/149), ptosis (2/149), and other rare ocular diseases. Except 5 cases with central retinal artery occlusion, other 144 COVID-19 ophthalmopathy cases showed good response to steroid therapy. Our study revealed an incidence of 6.09% for COVID-19 ophthalmopathy in outpatients at our Neuro-ophthalmology clinic during last resurgence of COVID-19 in China, and demonstrated that SARS-CoV-2 infection could induce an initial onset or a relapse of ophthalmic diseases, and that ocular involvement might manifest as the initial or even the only presentation of COVID-19.

Knee osteonecrosis after SARS-CoV-2 infection: a systematic case-based review.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for coronavirus disease 2019 (COVID-19). Patients with COVID-19 manifested symptoms mainly related to the respiratory system, but also the musculoskeletal system can be involved. COVID-19 has been described as a possible cause of knee osteonecrosis (ON). A systematic review was performed to investigate the hypothetical correlation between COVID-19 and knee ON. Methods: Inclusion criteria were all articles reporting cases of knee ON after a diagnosis of SARS-CoV-2 infection. Considering that COVID-19 is an emerging disease, all levels of evidence studies were included. Results: Finally, two case series and three case reports were included. We extracted data regarding demographic and clinical characteristics, details of magnetic resonance imaging (MRI), use of corticosteroids (CCS), temporal correlation between ON and COVID-19, treatment of the lesion and its outcomes. A total of seven cases of post-COVID knee ON have been described. Knee pain arose on average 11 weeks after the diagnosis of COVID-19. All patients had knee MRI showing ON. CCS were used to treat COVID-19-related symptoms in four cases. Conservative treatment was successful in five patients. Conclusions: The correlation between COVID-19 and ON remains unclear. Probably post-COVID-19 ON has a multifactorial origin in which factors related to the patient, consequences of COVID-19 and CCS therapy add up to cause a reduction of blood supply and bone vitality until ON is triggered. A greater number of patients is needed to clarify the role of COVID-19 in the etiopathogenesis of knee ON.

COVID-19-Related Multi-systemic Inflammatory Syndrome in Children (MIS-C).

Multisystem inflammatory syndrome in children (MIS-C) is a severe complication of SARS-CoV-2 infections in children. This syndrome manifests about a month after the initial viral infection and is characterized by fever, multiorgan dysfunction, and systemic inflammation. This chapter will review the emergence, epidemiology, clinical characteristics, diagnosis, pathophysiology, immunomodulatory treatment, prognosis, outcomes, and prevention of MIS-C. While the pathophysiology of MIS-C remains to be defined, it is a post-infection, hyperinflammatory syndrome of childhood with elevated inflammatory cytokines.

Validation of a phenotyping method to identify PRRSV-resilient sows and its impact on sow stayability.

Endemic and epidemic outbreaks of porcine reproductive and respiratory syndrome virus (PRRSV) are causing large economic losses in commercial pig production worldwide. Given the complexity of controlling this disease with vaccines or other biosecurity measures, the selection for pigs with a natural resilience to this infection has been proposed as an alternative approach. In this context, we previously reported a vaccine-based protocol to classify 6-week-old female piglets from one farm into resilient and susceptible phenotypes. Subsequent analysis showed that resilient sows had fewer lost piglets during a PRRSV epidemic. In the present study, we validated the results in four additional farms by showing a robust effect on the percentage of piglets lost (P<0.05). We were able to associate the resilient phenotype with a 2-4% reduction in piglet losses on sow farms in both endemic and endemic/epidemic situations. Also consistent with previous results, susceptible sows delivered on average, almost 0.5 more piglets born per parity (P<0.05). However, we show here that resilient sows have a longer stayability in the farm (+57 d; P<0.05) and +0.3 more successful parities (P<0.05), which balances the total number of piglets born and born alive in the full productive life of the sow between the two groups. Resilient sows thus contribute towards to a more sustainable production system, reducing sow replacement and piglet mortality. The validation of this protocol on four independent production farms paves the way for the study of the genetic variation underlying the resilient/susceptible classification, with a view to incorporating this information into selection programs in the future.

Enhancing disease surveillance and preparedness: An early warning tool for disease occurrence in U.S. swine breeding herds.

Understanding regional disease risk is critical for swine disease prevention and control. Since 2011, the Morrison Swine Health Monitoring Project (MSHMP) has strengthened partnerships among practitioners and producers to report health events (e.g., porcine reproductive and respiratory syndrome (PRRS) virus outbreaks) at the U.S. national level. Using MSHMP data and PRRS as an example, an early regional occurrence warning tool to provide near-real-time alerts was developed. MSHMP-participating production systems were invited to enroll. An algorithm was developed to calculate the number of PRRSV-positive sites near each enrolled site, determined from site-specific radius. The radius was determined in three steps. First, an initial radius of 25 miles was set for sites in pig-dense states and 50 miles for others. Secondly, four variables were generated to account for the sites within the initial radius: A) Total number of PRRSV-positive sites; B) Number of PRRSV-positive sites from other production systems; C) Total number of sites enrolled, and D) Total number of sites monitored by MSHMP. Subsequently, the reporting radius was automatically increased when confidentiality concerns arose. Results were compiled into system-specific reports and shared weekly with each participant. Reports have been shared since May 9, 2023, representing 178 breeding sites, comprising approximately 565 K sows. Examples of how participants use these reports include adjusting biosecurity programs, frequency of supply introduction, and transportation routes. The early occurrence warning tool developed in this study enhances producers' ability to communicate effectively and respond quickly to health threats, mitigating regional disease while preparing for foreign disease introductions.

Outcome of Glomerular Disease Manifesting After Vaccination Against Severe Acute Respiratory Syndrome Coronavirus 2.

Introduction Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can upregulate the immune system and may contribute to glomerular disease (GD). Here, we describe a spectrum of GD that manifested following vaccination against SARS-CoV-2 (COVID-19 vaccinations). Material and methods This was a descriptive study of 10 cases enrolled between January 2021 and January 2023. Patients with biopsy-proven GD that manifested following COVID-19 vaccinations were included. Results We found 10 cases of biopsy-proven GD following the COVID-19 vaccination. This included five cases of minimal change disease (MCD), three cases of focal segmental glomerulosclerosis (FSGS), one case of C3 glomerulonephritis (C3GN), and one case of IgA nephropathy (IgAN). The pre-existing disease was found in the last two patients (IgAN and C3GN) who got unmasked following vaccination. We did not observe any relation between vaccine type (Covisheld; six cases vs. Covaxin; four cases) and GD. In most cases (8/10 cases, 80.0%), GD developed after a repeat dose (second or booster dose). The onset time following vaccination was typically less than a week, and even less following a repeat dose. Conclusion Post-vaccination GD can be either de novo or a flare-up of a pre-existing one. The onset time following vaccination was typically less than a week for both Covishield and Covaxin.

Exploratory application of a cannulation model in recently weaned pigs to monitor longitudinal changes in the enteric microbiome across varied porcine reproductive and respiratory syndrome virus (PRRSV) infection statuses.

Introduction: The enteric microbiome and its possible modulation to improve feed conversion or vaccine efficacy is gaining more attention in pigs. Weaning pigs from their dam, along with many routine procedures, is stressful. A better understanding of the impact of this process on the microbiome may be important for improving pig production. The objective of this study was to develop a weaner pig cannulation model, thus allowing ileum content collection from the same pig over time for 16S rRNA sequencing under different porcine reproductive and respiratory syndrome virus (PRRSV) infection statuses. Methods: A total of 15 3-week-old pigs underwent abdominal surgery and were fitted with an ileum cannula, with ileum contents collected over time. In this pilot study, treatment groups included a NEG-CONTROL group (no vaccination, no PRRSV challenge), a POS-CONTROL group (no vaccination, challenged with PRRSV), a VAC-PRRSV group (vaccinated, challenged with PRRSV), a VAC-PRO-PRRSV group (vaccinated, supplemented with a probiotic, challenged with PRRSV), and a VAC-ANTI-PRRSV group (vaccinated, administered an antibiotic, challenged with PRRSV). We assessed the microbiome over time and measured anti-PRRSV serum antibodies, PRRSV load in serum and nasal samples, and the severity of lung lesions. Results: Vaccination was protective against PRRSV challenge, irrespective of other treatments. All vaccinated pigs mounted an immune response to PRRSV within 1 week after vaccination. A discernible impact of treatment on the diversity, structure, and taxonomic abundance of the enteric microbiome among the groups was not observed. Instead, significant influences on the ileum microbiome were observed in relation to time and treatment. Discussion: The cannulation model described in this pilot study has the potential to be useful in studying the impact of weaning, vaccination, disease challenge, and antimicrobial administration on the enteric microbiome and its impact on pig health and production. Remarkably, despite the cannulation procedures, all vaccinated pigs exhibited robust immune responses and remained protected against PRRSV challenge, as evidenced by the development of anti-PRRSV serum antibodies and viral shedding data.