Search Results (1,473)

Background/Objectives: In the first months of their life, infants rely on maternal antibodies for immune protection. Breastmilk is a major source of these defenses, supplying secretory IgA, IgG, and IgM that help guard mucosal surfaces against pathogens such as SARS-CoV-2. Most studies on breastmilk immunity in the context of COVID-19 have emphasized circulating monomeric IgA, rather than the multimeric secretory IgA (sIgA) that is active at mucosal barriers. This study assessed in-depth the contribution of breastmilk antibody subtypes to SARS-CoV-2 neutralization capacity and how these profiles differ following maternal COVID-19 infection versus vaccination during pregnancy or postpartum. Methods: In this prospective cohort study, breastmilk samples were collected longitudinally from individuals who had COVID-19 during pregnancy or received COVID-19 mRNA vaccination during pregnancy or postpartum. Serological assays measured IgG, IgM, systemic IgA, and secretory IgA against SARS-CoV-2 spike and nucleocapsid antigens. Results: COVID-19 infection during pregnancy resulted in significantly higher systemic and secretory IgA levels compared to vaccination. Secretory IgA demonstrated a strong correlation with neutralization capacity. Principal component analysis revealed distinct antibody profiles in COVID-19-exposed individuals versus vaccinated cohorts, with significant overlap between pregnancy and postpartum vaccination groups. Conclusions: Although both COVID-19 vaccination and disease elicit sustained COVID-19-related antibodies in breastmilk, COVID-19 infection elicits a broader and more diverse antibody response in breastmilk, specifically with a greater secretory IgA generation. These findings support the value of maternal vaccination to safely confer mucosal immunity to neonates and the need for optimized vaccine formulations for mucosal immunity. Full article

Background/Objectives: Canine papillomavirus (CPV) is an important viral pathogen associated with papillomatosis in dogs, with canine papillomavirus type 1 (CPV1) and type 2 (CPV2) among the most prevalent and clinically relevant genotypes. The L1 capsid protein is a major immunogenic antigen of papillomaviruses; however, conserved linear B-cell epitopes shared between CPV genotypes remain poorly defined. This study aimed to identify conserved cross-reactive B-cell epitopes within CPV1 and CPV2 L1 proteins and to evaluate their preliminary immunoreactivity. Methods: Conserved linear B-cell epitopes were predicted through integrated bioinformatic and structural analyses based on sequence conservation and surface accessibility. Three candidate epitopes were selected. Recombinant CPV1 and CPV2 L1 proteins were expressed in Escherichia coli (E. coli), purified, used as recombinant L1 antigens, together with BSA-conjugated synthetic epitope peptides for mouse immunization. Antigen-specific IgG responses were assessed by ELISA, antigen-associated IFN-γ responses were evaluated by ELISpot, and cross-reactive antibody recognition was assessed by Western blot. Results: Recombinant L1 proteins induced strong antigen-specific IgG responses in mice. The selected peptides induced detectable but weaker humoral responses compared with the recombinant L1 proteins. Among the three epitopes, TPSGSLV and TVVDNTR elicited antibodies that recognized both CPV1 and CPV2 L1 proteins, while the epitope VIVPKVS showed minimal or no detectable immunoreactivity. ELISpot analysis showed only modest antigen-associated IFN-γ responses, particularly in peptide-immunized groups. Conclusions: This study identified conserved cross-reactive linear B-cell epitope candidates within CPV1 and CPV2 L1 proteins and provided preliminary immunological evidence supporting their potential relevance for CPV antigen design. However, peptide-induced responses were weaker than those induced by recombinant L1 proteins, and VLP formation, antibody neutralizing activity, and protective efficacy were not evaluated. Further studies in dogs, including optimized antigen-display platforms, neutralization assays, and protection studies, are required to determine the practical value of these epitopes for CPV vaccine development. Full article

The extraordinary genetic diversity of human immunodeficiency virus type 1 (HIV-1), driven by high mutation and recombination rates, poses significant challenges for diagnostics, therapy, and vaccine development. While variable regions enable immune escape, hyperconserved regions are critical for viral function and represent promising targets for novel therapeutic interventions. This study aimed to develop and validate a bioinformatic algorithm for quantitative assessment of sequence conservation and automated identification of functionally significant conserved regions across all major HIV-1 proteins. A total of 1119 full-length HIV-1 genome sequences representing major subtypes (A1, A2, A6, B, C, D, F1, F2, G, H, J, K) were analyzed. Normalized Shannon entropy (S-index) was calculated for each alignment column. Statistical thresholds for conserved regions were established using 95% confidence intervals derived from bootstrap resampling. Two complementary algorithms, clustering and local maxima detection, were applied to identify conserved regions, which were subsequently mapped to known functional domains based on literature data. Protein conservation varied markedly, with S_m values ranging from 0.784 (Vpu) to 0.920 (Pol). Gag, Pol, and Vpr demonstrated the highest overall conservation, while Env, Rev, Tat, and Vpu exhibited pronounced variability interspersed with conserved domains. In total, 25 conserved regions in Gag, 49 in Pol, 28 in Env, and 6–4 regions in accessory proteins (Vif, Vpr, Rev, Tat, Nef, Vpu) were identified. These regions corresponded to critical functional elements including enzyme catalytic centers, zinc fingers, receptor-binding sites, protein interaction interfaces, and membrane-anchoring domains. The developed computational framework enables statistically grounded identification of evolutionarily constrained regions across analyzed HIV-1 subtypes. The identified conserved regions represent candidate sites for further investigation and may inform downstream studies focused on antiviral target prioritization, immunogen design, and diagnostic assay development. However, their translational applicability requires additional analytical, structural, and experimental validation. Full article

Background: The elimination of measles is a public health priority for the World Health Organization. During the COVID-19 pandemic from 2020 to 2022, the number of cases in Iraq decreased. However, a surge in cases started in late 2022. The aims of this study are to understand and describe the epidemiology of the surge of measles compared to reported cases in 2018 and 2019. Secondarily, they are to identify high clusters to find possible causes and implement prevention efforts accordingly, and low clusters of measles to identify possible protective factors. Methods: Frequencies were used to describe the univariate characteristics of cases reported each year. The chi-square test of independence was used to test differences by age; p-values less than 0.05 were considered statistically significant. Gi cluster analysis was used to determine where there were high and low clusters of cases in each district. Results: The number of clinically confirmed cases of measles rose dramatically in 2023 (14,301) and early 2024 (33,048) compared to 2018 (1044) and 2019 (4586). Most patients were less than one year to 14 years of age. The percentage of patients aged 5–14 years was higher in 2023 (32.8%) and 2024 (30.0%) than in 2018 (15.9%) and 2019 (22.1%). Males were consistently more prevalent than females throughout all study years. Almost 5% (1545) of patients were vaccinated; the remainder were unvaccinated or had unknown vaccination status. Only 1% reported a history of contact with infected patients. The case fatality ratio was 0.06% in 2023 and 0.2% in early 2024. Despite the recent surge in cases, 27 of the 153 districts (17.4%) had low clustering. Conclusions: The recent surge in measles cases in Iraq was found to be in those below 15 who are commonly associated with the disease. Clusters of high reporting were mainly in the middle of Iraq while clusters of low reporting were mainly in the north. We recommend continuing to study clusters of measles and vaccine coverage to direct prevention efforts. Full article

Objective: To identify demographic, clinical, and behavioural determinants of COVID-19 vaccination and antiviral uptake in Australia using the Capability, Opportunity, Motivation-Behaviour (COM-B) framework with psychometric validation and LASSO-enhanced variable selection. Methods: Cross-sectional analysis of the 2024 KAB BREATHE survey (n = 5177) of Australian adults, intentionally enriched for risk-stacked (more than 1 chronic condition). Primary outcomes included 2023/2024 COVID-19 booster receipt, future vaccine intentions, vaccine/antiviral beliefs and antiviral uptake. Predictors included demographics, chronic conditions, and domain-specific leave-one-out (LOO) COM-B scores standardised to mean = 0, SD = 1. COM-B domains were assessed using Cronbach’s alpha. Univariate and multivariable logistic regression models were complemented by LASSO penalised logistic regression with 10-fold cross-validation. Results: Among 5177 Australian adults, the mean age was 51.5 years (SD 16.5), 61.4% (3179/5177) were female, and 70.3% (3638/5177) were classified as risk-stacked. Booster uptake declined sharply from 50.8% (2023) to 19.1% (2024). Cronbach’s alpha showed poor internal consistency for Capability (α = 0.006) and Opportunity (α = −0.383) but was acceptable for full Motivation (α = 0.78). In adjusted models, age (aOR 1.02–1.03 per year), medically associated risk factors (aOR 1.66–3.51), and tertiary education (aOR 1.34–1.79) consistently predicted higher uptake and intention. Renting (aOR 0.59–0.78) and current employment (likely inversely associated with age) (aOR 0.73–0.83) were associated with lower uptake across all vaccine outcomes. Adding LOO COM-B scores substantially improved model fit (e.g., 2024 booster AUC 0.73→0.83); Motivation per SD was the strongest predictor (aOR 2.44–4.94 for vaccine outcomes, 1.52–2.49 for antivirals). LASSO models achieved CV-AUCs of 0.78–0.87. Among COVID-positive respondents (n = 2576), only 15.2% received antiviral treatment. Conclusions: Age, clinical risk, and socioeconomic factors, particularly housing tenure and employment status, are key drivers of COVID-19 preventive behaviours (either positively or negatively). The COM-B framework, when corrected for circular prediction and validated via Cronbach’s alpha and LASSO, provides substantial explanatory value. Targeted interventions should address structural barriers faced by renters and younger, employed individuals while leveraging high motivation among older adults and clinically vulnerable groups. Implications for Public Health: These findings support a shift from knowledge-based campaigns towards equity-focused, multi-level public health strategies that address structural barriers to COVID-19 vaccination and antiviral access in Australia. Full article

The hepatitis B (HBV), C (HCV), and D (HDV) viruses remain a major public health burden. Occult HBV infection (OBI) represents a hidden reservoir with clinical and epidemiological significance, yet its prevalence in Northwest Russia is unknown. We aimed to comprehensively assess the serological and molecular epidemiology of HBV, HCV, and HDV in St. Petersburg and the Leningrad region. Methods. In this cross-sectional study, 6773 apparently healthy volunteers were enrolled. Plasma samples were tested for hepatitis B surface antigen (HBsAg), antibodies to HBV core antigen (anti-HBc), antibodies to HBsAg (anti-HBs), antibodies to HCV (anti-HCV), and antibodies to HDV (anti-HDV) by ELISA. All anti-HCV- and anti-HDV-positive samples were tested for HCV RNA and HDV RNA by real-time PCR. All samples were tested for HBV DNA using a highly sensitive in-house nested real-time PCR assay (detection limit: 5 IU/mL). All “HBV DNA-positive, HBsAg-negative” cases confirmed by two independent extractions were classified as OBI. Vaccination status, self-reported history, and iatrogenic interventions were recorded. Results. Overall seroprevalence values were: HBsAg 1.7%; anti-HBc 11.3%; anti-HBs 43.0%; anti-HCV 1.9%; and anti-HDV 0.6%. Anti-HBc increased sharply with age (3.1% in children to 26.4% in the elderly, p < 0.0001), while anti-HBs declined (69.9% to 29.8%, p < 0.0001). HBV DNA was detected in 118 participants (1.7%). Of these, only 73 individuals (1.1%) were HBsAg-positive, while the remaining 45 participants (0.7%) had undetectable HBsAg, meeting the criteria for OBI. OBI was detected across all age groups, including children. Serological profiling of OBI cases revealed that 57.8% lacked both anti-HBc and anti-HBs, 35.6% had isolated anti-HBs, 2.2% had isolated anti-HBc, and 4.4% had both antibodies. HCV RNA was detected in 15.0% of anti-HCV-positive individuals (all adults). No HDV RNA was detected. Self-reported history underestimated true infection rates: 1.4% of those denying HBV infection were HBsAg-positive and 10.6% were anti-HBc-positive. Among those denying HCV infection, 1.4% were anti-HCV-positive. Vaccination coverage was 70.8%, declining from 90.9% in children to 39.0% in the elderly (p < 0.0001). Among vaccinated individuals, 48.0% lacked protective anti-HBs (<10.0 mIU/mL). Conclusions. This comprehensive serological and molecular study in Northwest Russia is the first to combine population-level serology with molecular detection of HBV, HCV, and HDV, including OBI in this region, and reveals that OBI accounts for a substantial proportion (38%) of all active HBV infections and is strongly associated with a history of iatrogenic interventions. The presence of OBI across all age groups, including children, shows that HBsAg screening alone substantially underestimates the true HBV burden. High rates of unrecognized infection and waning vaccine-induced immunity, highlight critical gaps in current surveillance. These findings provide an evidence-based rationale for integrating molecular testing into screening algorithms and for considering booster vaccination strategies to achieve viral hepatitis elimination goals. Full article

Classical swine fever (CSF), caused by the classical swine fever virus (CSFV), is an acute, febrile, and highly contagious disease that has led to significant economic losses in the global swine industry. Although the attenuated lapinized CSF vaccine (C-strain) has effectively controlled CSF outbreaks in China since the 1950s, it remains challenging to serologically differentiate infected from vaccinated animals (DIVA). Currently, the application of E2 subunit vaccines allows for DIVA by detecting antibodies against the E^rns protein. Therefore, this study aimed to develop a blocking ELISA for CSFV E^rns antibody detection using porcine monoclonal antibodies (mAbs) derived from single B cell technology. Peripheral blood mononuclear cells (PBMCs) were isolated from immunized pigs, and single CD21⁺IgM⁻E^rns-His tag⁺ B cells were sorted via flow cytometry. Using one-step PCR, full-length genes of porcine IgG heavy and light chains were amplified separately, yielding 11 porcine mAbs against the CSFV E^rns protein. Among these, three mAbs (E0S3, E0S5, and E0S10) exhibited broad reactivity, while two (E0S1, E0S4) showed no cross-reaction with bovine viral diarrhea virus (BVDV). Using mAb E0S4 as the blocking antibody, a blocking ELISA was established and optimized. The assay demonstrated a detection limit of 1:128, no cross-reactivity with other swine viruses or BVDV, and intra- and inter-assay coefficients of variation below 10%. ROC curve analysis determined an optimal cut-off value of 48.4%, with high sensitivity and specificity. In conclusion, the developed blocking ELISA provides a reliable tool for high-throughput serological surveillance, facilitating the DIVA strategy and contributing to CSF eradication programs. Full article

Background/Objectives: COVID-19 vaccine resistance was detrimental to herd immunity and worsened COVID-19 morbidity and mortality during outbreaks. Despite more evidence showing reactionary behavior among residents exposed to vaccine mandates, little research has been conducted on the effects of state proof-of-vaccine (POV) mandate bans in the United States (US). We sought to investigate the causal effects of POV mandate bans, overall and stratified by policy passage via executive order or state legislature, on first-dose COVID-19 vaccinations. Methods: In the contiguous US, 21 states enacted POV mandate bans from 8 February 2021–25 October 2021. Using a geographic regression discontinuity design, we selected treatment and control counties within 150 miles of the POV mandate ban state border. The resulting sample was 4612 county-observations and 2466 unique counties. We conducted two-way fixed-effects estimation to compare changes in weekly, first-dose COVID-19 vaccinations among individuals <65 years old before and after POV mandate ban enactment between treatment and control counties. Results: Among executive order POV mandate ban counties, we saw an additional increase in weekly, first-dose COVID-19 vaccinations following POV mandate ban enactment when compared to controls. There was an additional 38.2% increase in Weeks 1–2, 40.6% in Weeks 3–4, 41.3% in Weeks 5–6, and 43.9% in Weeks 7–8. Conclusions: While seemingly counterintuitive, these findings follow Psychological Reactance Theory. Once the perceived threat to freedom was removed, reactance to COVID-19 vaccinations declined and constituents received the COVID-19 vaccine of their own volition. Future public health efforts should consider potential reactance to mandatory policies and tailor efforts to community values. Full article

The Getah virus (GETV) is a mosquito-borne pathogen that infects diverse hosts, including pigs, horses, and humans, which can cause swine reproductive disorders such as abortion and stillbirth, posing a potential threat to animal and public health. Therefore, there is an urgent need for efficient and accurate serological diagnostic methods for surveillance and control of GETV. However, commercial diagnostic kits for swine GETV infection remain unavailable. In this study, we developed a novel enzyme-linked immunosorbent assay (ELISA) based on a GETV-specific epitope peptide (E2EP3) for serological detection. The N-terminally biotinylated E2EP3 peptide was synthesized, and the reaction conditions were systematically optimized, resulting in a cut-off value of 0.363. The assay exhibited no cross-reactivity with Japanese encephalitis virus (JEV), porcine circovirus type 2 (PCV2), porcine circovirus type 3 (PCV3), pseudorabies virus (PRV), or classical swine fever virus (CSFV). It demonstrated good reproducibility and high sensitivity, detecting GETV-positive serum diluted up to 1:640. The overall agreement rate reached 95%, consistent with a conventional recombinant GETV E2 protein-based ELISA. Benefiting from the biotin–streptavidin system, this assay achieved strong signal amplification and low background. Moreover, the procedure is simple, cost-effective, and stable, making it suitable for GETV large-scale serological surveillance and vaccine evaluation. Full article

Background/Objectives: Recombinant poliovirus (PV) virus-like particle (VLP) antigens mimic the conformation of the surface proteins in native PVs (i.e., serotype-specific D-antigen epitopes). Since they lack genomes and are non-infectious, PV-VLPs offer the promise of a safer, next-generation polio vaccine compared to traditional inactivated (IPV) or attenuated live (OPV) vaccines. Sandwich D-antigen ELISA formats are commonly used to measure the in vitro potency values (relative D-antigen content, DU/mL) of unadjuvanted trivalent IPV antigens. If IPV is formulated with aluminum-salt adjuvants, however, a pretreatment step (i.e., adjuvant dissolution or antigen desorption) is required, which may compromise antigen integrity during sample handling. Methods: This work describes the development of three competitive ELISAs to measure the relative D-antigen content of aluminum-salt adjuvanted PV-VLPs (Types 1, 2, 3) without the need for pretreatment. Results: First, key assay parameters were established, including specificity, accuracy, precision, linearity, limit of quantification, and stability-indication. Next, preformulation characterization studies were performed with these methods including (1) rank-ordering the inherent thermal stability profiles of the PV-VLPs (Types 1 > 3 > 2) in-solution and adsorbed to an aluminum phosphate adjuvant (AdjuPhos™, AP) and (2) determining the effect of formulation variables on the thermal stability profiles of AP-adsorbed PV-VLPs including antimicrobial preservatives (thimerosal, 2-PE) and five different antigens present in pediatric combination vaccines (D, T, wP, Hib, Hep B). Conclusions: The development and application of three competitive D-antigen ELISAs were demonstrated, and future use in formulation and storage stability studies with the AP-adjuvanted, trivalent PV-VLPs (Types 1, 2, 3) is discussed with the long-term goal to develop a stable, efficacious, multi-dose, hexavalent combination vaccine presentation. Full article

Efficient in vitro production of rabies virus is essential for vaccine development and quality control applications. High-density cultivation systems offer practical advantages for rabies virus production but also create culture conditions in which nutrient depletion, waste accumulation, and progressive deterioration of host-cell condition may limit infectious virus output. In this study, we evaluated the effects of sodium pyruvate supplementation on rabies virus CVS-11 production in Vero and BSR cells cultivated in a high-density macrocarrier-based tide-motion culture system under serum-containing and serum-free conditions, with complementary comparative observations in conventional monolayer cultures of BHK cells. Cultures were infected at a multiplicity of infection of 0.01, and infectious virus production was assessed over time, together with cell density, glucose consumption, and pH dynamics. Sodium pyruvate supplementation was associated with significantly higher infectious virus titers, delayed culture deterioration, prolonged maintenance of viable cell populations, and higher peak infectious titers in both Vero and BSR cultures. The highest infectious titers were observed under serum-free pyruvate-supplemented conditions, reaching 7.5 log₁₀ FFU/mL in Vero cells and 7.2 log₁₀ FFU/mL in BSR cells. Across the tested conditions, serum-free cultivation and pyruvate supplementation were both associated with significantly higher peak infectious titers. In contrast, exploratory correlation analysis based on condition-level summary values indicated an inverse association between minimum culture pH and peak infectious titer. Together, these findings show that sodium pyruvate supplementation can improve infectious rabies virus yield and prolong the productive phase in high-density macrocarrier-based cultures, supporting its use as a practical culture-modulation strategy for CVS-11 production in adherent cell systems. Full article

Mesothelin (MSLN) is a cell surface glycoprotein with limited expression in normal tissues but frequent overexpression in solid tumors, including gynecological malignancies. This review summarizes the state of the art on the biological role, diagnostic value, prognostic significance, and therapeutic potential of MSLN in ovarian, endometrial, and cervical cancers. Evidence from clinical and experimental studies indicates that MSLN contributes to tumor progression through interactions with CA125, promotion of cell adhesion and peritoneal metastasis, activation of oncogenic signaling pathways, modulation of immune responses, and development of chemoresistance. Elevated MSLN expression has been associated with advanced clinical stage of the disease, platinum resistance, and poorer survival outcomes, particularly in ovarian cancer patients, although prognostic findings remain inconsistent. Circulating soluble MSLN may serve as a minimally invasive biomarker and may improve diagnostic accuracy when combined with established markers. Therapeutic MSLN strategies—antibody-drug conjugates, CAR-T and NK cell therapies, monoclonal antibodies, immunotoxins, vaccines, and checkpoint blockade—provide promising pre-clinical and early clinical results, particularly in resistant or recurrent forms of the disease. Overall, MSLN constitutes a promising target for precision oncology in gynecological cancers, although further clinical studies are required to validate its diagnostic utility and optimize targeted therapeutic approaches. Full article

Squalene, a high-value triterpenoid precursor widely used in pharmaceuticals and vaccine adjuvants, is primarily sourced from shark liver oil—an unsustainable practice that has driven interest in developing plant-based production alternatives. The first committed reaction in triterpenoid biosynthesis is catalyzed by squalene synthase (SQS), yet no SQS gene has been characterized in Amaranthus tricolor, a species recognized for its high squalene content. Here, we cloned and functionally characterized AtrSQS, a novel squalene synthase gene isolated from A. tricolor for the first time. Sequence analysis revealed that AtrSQS contains conserved domains and six characteristic motifs shared among plant SQSs, with high homology to orthologs from dicotyledonous species. To investigate its functional role in squalene biosynthesis, AtrSQS was overexpressed in Nicotiana tabacum under the CaMV 35S promoter. Transgenic lines exhibited significantly increased AtrSQS expression and accumulated squalene up to 6.81 μg/g dry weight, a 4.76-fold increase over wild-type plants. Additionally, the content of downstream product 2,3-oxidosqualene was also significantly elevated in the transgenic lines. Integrated transcriptomic and metabolomic analyses revealed that AtrSQS overexpression upregulated key mevalonate pathway genes (AACT, HMGS, MVD) and FPPS. Meanwhile, it suppressed competitive carotenoid biosynthesis and the production of an SQS-specific inhibitor, indicating a successful redirection of metabolic flux toward squalene production. These findings demonstrate that AtrSQS is crucial for squalene biosynthesis and provide both a valuable genetic resource and mechanistic insights for engineering plant-based squalene production systems. Full article

Background/Objectives: Primary Care Physicians (PCPs) are widely regarded as trusted sources of health information and can play a pivotal role in increasing seasonal influenza vaccination (SIV) within their communities. We aimed to explore PCPs’ attitudes toward SIV and their views regarding proposed strategies to enhance SIV uptake in the evolving post-pandemic landscape. Methods: A qualitative study utilizing semi-structured individual interviews with a nationwide sample of 25 PCPs was conducted. Results: Physicians’ attitudes toward SIV were overwhelmingly positive; they recognized its protective value for individuals and the community alike, its efficacy in averting serious illness, and its proven safety profile. Regarding strengthening SIV uptake, PCPs positively appraised the following strategies: (a) viewing all clinical encounters as opportunities for vaccination; (b) outsourcing vaccination to nursing, allied health staff and community pharmacists, provided that specific prerequisites are met; (c) forwarding personalized notifications to health providers and (d) the public; and (e) establishing at-home vaccinations. Financial incentives would reportedly act as tangible acknowledgement and motivate PCPs to work toward primary prevention. However, others have argued that SIV is inherently embedded in their duty as PCPs, and potential remunerations would dwindle the public’s confidence in PCPs. Establishing incentives for the general population reportedly minimizes confidence and the perceived value of SIVs and was assessed to be ineffective in the Greek context. Promoting SIVs through video games was considered to be less effective for the adult population. Conclusions: Mapping PCPs’ insights is key in designing effective SIV strategies that are concurrent with communities’ values, needs, and learnt experience from the COVID-19 pandemic. Full article

Background: During the COVID pandemic increased rates of intensive care unit (ICU) admission, mechanical ventilation, caesarean delivery, and preterm birth among women with SARS-CoV-2 infection in pregnancy were recorded. Purpose: This study describes the clinical course and perinatal outcomes of pregnant women with COVID-19 across pre- and post-vaccination periods. Methods: This study included all pregnant women with confirmed SARS-CoV-2 infection who subsequently delivered at the University General Hospital of Larissa between March 2020 and May 2023. Demographics, comorbidities, gestational age at infection and at delivery, COVID-19 symptoms, need for hospitalization, obstetric complications, mode of delivery, and neonatal outcomes were documented. An assessment of ischemia-modified albumin (IMA) was performed in a subset of women. Results: A total of 327 women (including 14 twin gestations) were recorded. Most women experienced mild disease while a minority required hospital admission, or intensive care (1.8 and 0.3% for the studied population, respectively). Fever and upper respiratory symptoms predominated, while radiologic evidence of pneumonia was rare. Overall preterm birth (<37 weeks) occurred in 13% of pregnancies and caesarean section in about two thirds of deliveries. Neonatal outcomes were favorable, with low rates of neonatal intensive care unit (NICU) admission and no early neonatal deaths. IMA values were higher during acute infection and declined towards recovery. Conclusion: Pregnant women with COVID-19 in Central Greece had predominantly mild clinical courses and excellent perinatal outcomes. IMA may represent a biologically plausible marker of disease activity, but further studies are needed. Full article