Search Results (468)

Antibody titer testing can be useful in controlling successful puppy immunization and can reduce unnecessary vaccinations in adult dogs. We evaluated three commercially available point-of-care tests (POCTs) for detecting antibodies against canine parvovirus (CPV-2), canine distemper virus (CDV) and canine adenovirus (CAV-1 and/or -2), comparing them to the reference virus neutralization (VN) assay. Sera from 200 client-owned dogs (13 healthy, 63 chronically diseased, 124 acute) and 60 specific pathogen-free (SPF) dogs, including 20 sera with maternally derived antibodies (MDA), were tested. All three POCTs demonstrated high sensitivity (79.0–100%) and specificity (97.8–100%) for CPV-2. In contrast, specificity for CDV and CAV was lower with POCT-1 (43.5% and 55.3%) and POCT-2 (42.4% and 79.2%), despite high sensitivity (CDV in both POCTs 98.7%; CAV POCT-1: 99.4%, POCT-2: 90.8%). POCT-3, by comparison, showed high specificity (CDV: 94.1%; CAV: 84.4%) but very low sensitivity (CDV: 17.4%; CAV: 33.1%). Only POCT-1 for CPV-2 detected MDA reliably, whereas the other two POCTs, and POCT-1 for CDV and CAV, did not. When compared to VN, the agreement in vaccination recommendations was 82% for POCT-1 and POCT-2, and 62% for POCT-3. In conclusion, all three POCTs reliably detected antibodies against CPV-2, including MDA with POCT-1. However, the lower specificity for CDV and CAV antibody detection in POCT-1 and POCT-2 raises concerns about misclassifying unprotected dogs as immune, while false-negatives with POCT-3 could lead to unnecessary vaccinations. Further optimization of all three POCTs for CDV and CAV is recommended. Full article

The lateral flow immunoassay (LFIA) is a widely utilized, rapid diagnostic technique characterized by its short analysis duration, cost efficiency, visual result interpretation, portability and suitability for point-of-care applications. However, conventional LFIAs have limited sensitivity, a challenge that can be overcome by the introduction of gold nanoparticles, which provide enhanced sensitivity and selectivity (compared, for example, to latex beads or carbon nanoparticles) for the detection of target analytes, due to their optical properties, chemical stability and ease of functionalization. In this work, gold nanoparticle-based LFIAs are developed for the detection of aflatoxin B1, and the relative performance of different morphology particles is evaluated. LFIA using gold nano-labels allowed for aflatoxin B1 detection over a range of 0.01 ng/mL–100 ng/mL. Compared to spherical gold nanoparticles and gold nano-flowers, star-shaped gold nanoparticles show increased antibody binding efficiency of 86% due to their greater surface area. Gold nano-stars demonstrated the highest sensitivity, achieving a limit of detection of 0.01ng/mL, surpassing the performance of both spherical gold nanoparticles and gold nano-flowers. The use of star-shaped particles as nano-labels has demonstrated a five-fold improvement in sensitivity, underscoring the potential of integrating diverse nanostructures into LFIA for significantly improving analyte detection. Moreover, the robustness and feasibility of gold nano-stars employed as labels in LFIA was assessed in detecting aflatoxin B1 in a wheat matrix. Improved sensitivity with gold nano-stars holds promise for applications in food safety monitoring, public health diagnostics and rapid point-of-care diagnostics. This work opens the pathway for further development of LFIA utilizing novel nanostructures to achieve unparallel precision in diagnostics and sensing. Full article

Background: There is growing interest in the potential role of manganese (Mn) in the development of Alzheimer’s Disease and related dementias (ADRD). Methods: In this nested pilot study of a ferroalloy worker cohort, we investigated the impact of chronic occupational Mn exposure on cognitive function through β-amyloid (Aβ) deposition and multi-omics profiling. We evaluated six male Mn-exposed workers (median age 63, exposure duration 31 years) and five historical controls (median age: 60 years), all of whom had undergone brain PET scans. Exposed individuals showed significantly higher Aβ deposition in exposed individuals (p < 0.05). The average annual cumulative respirable Mn was 329.23 ± 516.39 µg/m³ (geometric mean 118.59), and plasma Mn levels were significantly elevated in the exposed group (0.704 ± 0.2 ng/mL) compared to controls (0.397 ± 0.18 in controls). Results: LC-MS/MS-based pathway analyses revealed disruptions in olfactory signaling, mitochondrial fatty acid β-oxidation, biogenic amine synthesis, transmembrane transport, and choline metabolism. Simoa analysis showed notable alterations in ADRD-related plasma biomarkers. Protein microarray revealed significant differences (p < 0.05) in antibodies targeting neuronal and autoimmune proteins, including Aβ (25–35), GFAP, serotonin, NOVA1, and Siglec-1/CD169. Conclusion: These findings suggest Mn exposure is associated with neurodegenerative biomarker alterations and disrupted biological pathways relevant to cognitive decline. Full article

Background: Understanding the duration and quality of immune memory following SARS-CoV-2 infection and vaccination is critical for informing public health strategies and vaccine development. While waning antibody levels have raised concerns about long-term protection, the persistence of memory B cells (MBCs) and T cells plays a vital role in sustaining immunity. Materials and Methods: We conducted a longitudinal prospective study over 12 months, enrolling 285 participants in total, either after natural infection or vaccination with BNT162b2 or mRNA-1273. Peripheral blood samples were collected at four defined time points (baseline, 1–2 months, 6–7 months, and 12–13 months after vaccination or disease onset). Immune responses were assessed through serological assays quantifying anti-RBD IgG and neutralizing antibodies, B-ELISPOT, and multiparameter flow cytometry for S1-specific memory B cells. Results: Both mRNA vaccines induced robust B cell and antibody responses, exceeding those observed after natural infection. Memory B cell frequencies peaked at 6 months and declined by 12 months, but remained above the baseline. The mRNA-1273 vaccine elicited stronger and more durable humoral and memory B-cell-mediated immunity compared to BNT162b2, likely influenced by its higher mRNA dose and longer prime-boost interval. Class-switched memory B cells and S1-specific B cells were significantly expanded in vaccine recipients. Natural infection induced more heterogeneous immune memory. Conclusions: Both mRNA vaccination and natural SARS-CoV-2 infection induce a comparable expansion of memory B cell subsets, reflecting a consistent pattern of humoral immune responses across all studied groups. These findings highlight the importance of vaccination in generating sustained immunological memory and suggest that the vaccine platform and dosage influence the magnitude and durability of immune responses against SARS-CoV-2. Full article

Background: Autoimmune liver diseases (ALDs) are a diverse group of chronic inflammatory disorders. Individuals with a history of one autoimmune disease (AD) are at a substantially increased risk of developing additional autoimmune conditions. Polyautoimmunity has increasingly been recognized as a factor associated with a more complex disease course and poorer long-term outcomes. Methods: This retrospective, cross-sectional observational study reviewed medical records of patients diagnosed with ALDs who had been admitted to the gastroenterology clinic. Results: A total of 457 patients with ALDs were included. Polyautoimmunity was present in 194 patients (42.5%), and multiple autoimmune syndrome (MAS) was diagnosed in 26 of these patients (5.7%). Serological comparisons revealed that antinuclear antibody (ANA) positivity was significantly more common in the polyautoimmunity group. Only 22.2% of the patients with polyautoimmunity were ANA-negative, compared with 52.9% in those without. An ROC curve analysis was conducted to assess the predictive value of clinical and laboratory variables for polyautoimmunity. Among all the tested parameters, ANA positivity (>+2) had the strongest predictive value (AUC: 0.724). A disease duration longer than 6.5 years followed, with a moderate discriminative capacity (AUC: 0.677). Additionally, lower albumin levels (<3.0 g/dL) and elevated erythrocyte sedimentation rates (ESRs) (>29.5 mm/h) were significantly associated with polyautoimmunity. Conclusions: In our cohort, 42.5% of patients had at least one additional autoimmune disorder, highlighting the need for a systemic and comprehensive approach to patient care. Simple and accessible markers—such as ANA titers, disease duration, albumin levels, and ESRs—may help to identify patients at greater risk. Full article

Malaria is still one of the biggest global health problems, especially in parts of the world, such as sub-Saharan Africa, which remains most heavily affected. Despite significant advancements in testing, treatment, and prevention, malaria continues to seriously impact millions, primarily young children and populations in rural and impoverished areas. This paper looks at how the malaria parasite works inside the body, how it avoids the immune system, and how it becomes resistant to current drugs. Thanks to new advances in genetic and biochemical research, scientists are discovering new weak points in the parasite that could lead to better treatments. New vaccines, like RTS, S and R21, along with antibody-based therapies, offer renewed hope; however, extending the duration of the immunity they induce and ensuring effectiveness across diverse parasite strains remain significant challenges. Solving the malaria crisis will require more than science—it also necessitates equitable and timely access to treatments, robust health systems, and international collaboration. Continued research and global cooperation bring the world closer to ending malaria for good. Full article

The feline calicivirus, herpesvirus, and panleukopenia viruses are major infections that cause serious diseases in cats; however, current trivalent vaccines have limitations in immune efficacy and their duration of protection. This study assesses the immune-enhancing effects of novel adjuvants (feline IL-15, IL-23, and metabolic modulators) on vaccine responses. Forty mice were randomly assigned to four groups: Group A (composite adjuvants), Group B (metabolic regulatory molecules and Mn adjuvant), Group C1 (Mn adjuvant), and Group C2 (a blank commercial vaccine). The results showed that Group A had significantly higher neutralizing antibody titers against calicivirus post-booster immunization, while both Groups A and B exhibited enhanced antibody responses against the herpesvirus and panleukopenia viruses. Notably, Group A displayed increased proportions of memory T cells, follicular B cells, and activated B cells. These findings suggest that the combination of feline IL-15, IL-23, and metabolic modulators are safe and effective immunoadjuvants for trivalent feline vaccines to promote immune cell differentiation and antibody production, thus representing a promising strategy to optimize vaccine efficacy. Full article

Background/Objectives: European Brown Hare Syndrome (EBHS) is an acute and highly contagious viral disease of hares that causes considerable economic losses on wild and captive-reared hares. No preventive treatments are currently available to defeat the disease. Immunoprophylactic and biosafety measures could be applied to prevent EBHS only in captive-reared hares, where vaccination is proposed as an effective strategy. Due to the lack of a cellular substrate for virus growth, commercially available vaccines are autovaccines produced from inactivated liver suspensions of hares dead for EBHS. Therefore, using a recombinant vaccine based on VP60 major capsid protein seems a viable alternative to overcome such a problem. Methods: the 6xHis C-terminal tagged VP60 protein of EBHSV was expressed and produced in baculovirus, purified by affinity chromatography and the self-assembled recombinant (rEVP60-His₆) protein. To establish the protective properties of rEVP60-His₆-based VLPs, hares were immunised with 50 and 100 µg of VLPs and parenterally challenged with EBHSV. Results: all hares vaccinated with 100 µg of VLPs survived after the experimental infection, demonstrating the excellent protective ability of this prototype VLPs-based vaccine. Conclusions: self-assembled EBHSV rEVP60-His₆ protein was successfully produced following a rapid, simple, low-cost protocol. Although the protective efficacy of such VLPs were experimentally demonstrated, some key aspects remain to be clarified, including the duration of protection, the entity of the antibody response, and the ability to stimulate cell-mediated response. Last, an additional aspect to be evaluated is whether the use of an adjuvant can determine whether its presence improves the performance of the recombinant VLPs vaccine. Full article

Background: Neonatal influenza is a rare condition. Young infants have immature immune defenses and are unable to receive direct vaccination; this can result in significant illness. Maternal anti-influenza immunization during pregnancy provides passive antibodies to the newborn via transplacental transfer, significantly decreasing the incidence and severity of influenza in early infancy. Nevertheless, the vaccination coverage during pregnancy remains low in many regions, leaving certain neonates without adequate protection. Methods: We present three cases of laboratory-confirmed influenza infection in neonates admitted to the “Sf. Ioan” Clinical Emergency Pediatric Hospital in Galați and conduct a literature review. The clinical presentation, co-infections, timing of antiviral therapy, laboratory findings, maternal vaccination status, and outcomes (including the hospitalization duration and recovery) were systematically analyzed for each case. Results: All three neonates were full-term and previously healthy, born to mothers who had not received influenza vaccinations during their pregnancies. They presented at ages ranging from 2 to 4 weeks with fever, respiratory symptoms including a cough, nasal congestion, and respiratory distress, as well as feeding difficulties. One case involved a co-infection with Bordetella pertussis, which manifested as a severe paroxysmal cough, cyanosis, and apnea. Laboratory findings in the cases with influenza alone indicated leukopenia accompanied by normal C-reactive protein levels. In the co-infection case, leukocytosis, lymphocytosis, and thrombocytosis were observed. All the infants received oseltamivir treatment within 48 h of the symptom onset; the case with pertussis co-infection also received azithromycin. Each infant required supplemental oxygen, but none necessitated mechanical ventilation. Clinical improvement was observed in all cases, with hospitalization ranging from 6 to 7 days and complete recovery without complications. Conclusions: Neonatal influenza may result in considerable morbidity, particularly in infants born to unvaccinated mothers. Positive outcomes, however, have been correlated with early diagnosis and antiviral treatment. Pertussis co-infection may exacerbate clinical progression, underscoring the importance of maternal immunization against both influenza and pertussis. In this case series, we aim to present three cases of laboratory-confirmed influenza in neonates born to mothers who were not immunized against influenza during pregnancy. These cases highlight the clinical presentations of neonatal influenza, underscore the risks associated with pertussis co-infection, and reinforce the importance of maternal influenza and Tdap vaccination for preventing severe outcomes in newborns. Full article

A killed, whole-cell vaccine was produced to induce immunity in dogs against leptospirosis. The vaccine, containing serovar Copenhageni, was produced and administered to 12 beagle dogs at both 8 and 12 weeks of age. Ten unvaccinated dogs of the same age group served as the control group. A live, virulent inoculum of Leptospira (1.52 × 10⁹–4.40 × 10⁹ leptospires per dog) was used to challenge the dogs at 2 weeks (Study 1) and 14 months (Study 2) post-booster vaccination. At regular intervals, pre- and post-challenge (PC), the microscopic agglutination test (MAT) was performed to measure antibody titers. Leptospiremia and leptospiruria were determined via culture, and the cytokine, biochemical, and pathological profiles of vaccinates and controls were also assessed. A high antibody response was measurable after booster administration. In Study 1 (onset of immunity), acute leptospirosis was observed in five (100%) out of five unvaccinated dogs. In contrast, no acute clinical leptospirosis developed in vaccinated dogs, except in one (20%) dog with mild clinical signs. In Study 2 (duration of immunity), mild clinical signs were observed in two (40%) of the control dogs, while all vaccinated dogs remained clinically normal. The incidence of leptospiruria and leptospiremia PC was lower in the vaccinated dogs compared to the unvaccinated group. Severe thrombocytopenia occurred in 100% (5/5) of the unvaccinated dogs in Study 1 that exhibited acute severe leptospirosis, whereas 80% (4/5) of the unvaccinated dogs in Study 2 showed mild to moderate thrombocytopenia 3 days after challenge. Four out of five unvaccinated dogs (80%) in Study 1 exhibited icteric tissues and hemorrhages in the lungs and mucosal surfaces of the stomach and intestines. A high IL-10 to TNF-α ratio, observed in the control group of both studies, and severe thrombocytopenia observed in the control group of Study 1, indicative of acute leptospiral disease, were detected. The vaccine prevented acute clinical leptospirosis and reduced the renal carrier state in beagle dogs, and further investigation is required using a larger sample size. Full article

Background: Zolbetuximab, a monoclonal antibody targeting claudin-18.2 (CLDN18.2), which was recently approved as first-line treatment for advanced gastric cancer (AGC), presents unique safety challenges, particularly infusion-related gastrointestinal toxicity and hypoalbuminemia. This study aimed to present our experience with zolbetuximab administration in patients with AGC, focusing on the safety and management effectiveness of our adapted protocol in routine clinical practice. Methods: This study presents our single-institution real-world experience implementing a proactive management protocol (“Project VYLOY”) using zolbetuximab to mitigate these toxicities. We adopted a standardized stepwise infusion protocol and antiemetic premedication to reduce infusion-related nausea and vomiting. Patients with CLDN18.2-positive advanced gastric or gastroesophageal junction adenocarcinoma who received zolbetuximab combined with chemotherapy were included. Results: Twenty-four patients were included. The median infusion duration was 215 min, with an interruption rate of 25.0%. In cycle 1, 62.5% experienced infusion-associated adverse events, primarily grade 1 nausea (54%) and vomiting (25%). Hypoalbuminemia (grade ≥ 2) occurred in 57% of first-line patients, potentially linked to zolbetuximab-induced gastritis and gastrointestinal protein loss. Proactive antiemetic support and infusion rate adjustments substantially reduced infusion interruptions in subsequent cycles (10.9%). Patients without prior gastrectomy had higher nausea and vomiting rates, confirming the stomach’s role in mediating toxicity. Conclusions: Our results suggest that proactive management can improve the safety and tolerability of zolbetuximab, especially by reducing infusion-related toxicity in real-world practice. Full article

Background: The introduction of biological drugs into clinical practice for the treatment of children with systemic juvenile idiopathic arthritis (sJIA) allows disease control but increases the risk of infectious events. Infectious events cause immunosuppressive therapy interruptions, leading to disease flare and life-threatening complications, namely macrophage activation syndrome. Our study aimed to evaluate the efficacy and safety of simultaneous vaccination against pneumococcal and Haemophilus influenzae type b (Hib) in children with sJIA. Methods: This study included 100 sJIA patients receiving immunosuppressive therapy who were simultaneously vaccinated against pneumococcal and Haemophilus influenzae type b (Hib) infections. The mean age of disease onset was 5.5 years. The median age at vaccination was 10 ± 4.5 years. Clinical and laboratory parameters of sJIA activity, immunization efficacy, and safety, including anti-SP and anti-Hib IgG antibodies, as well as all vaccination-related adverse events (AEs), were recorded in every patient before, 3 weeks after, and 6 months after vaccination. Results: At the time of vaccination, 29% of patients did not meet the criteria for the inactive disease stage, as defined by C. Wallace: active joints were present in 34.5% of patients, systemic manifestations (rash and/or fever) were present in 41.3%, and 24.2% of patients had solely inflammatory laboratory activity. The protective titer of anti-SP and anti-Hib IgG antibodies was detected in the majority of patients 3 weeks after vaccination (100% and 93%, respectively). The results remained unchanged (99% and 92%, respectively) for 6 months of follow-up, compared to the baseline (91% and 37%, p = 0.000001). Anti-SP IgG and anti-Hib titers raised from 48.3 (18.2; 76.5) and 0.64 (0.3; 3.2) U/mL at the baseline to 103.5 (47.3; 185.4) and 4 (3.5; 4.2) U/mL at D22 and 105 (48.7; 171.8) and 4 (3.8; 4) U/mL (EOS), respectively. Immunosuppressive therapy regimens (combined therapy or biological disease-modifying antirheumatic drug monotherapy) did not influence the immunogenic efficacy of vaccination. The incidence of infectious complications (p = 0.0000001) and antibiotic prescriptions (p = 0.0000001) decreased by more than two times, to 29.9 and 13.8 events per 100 patient months, respectively, within 6 months after vaccination—the average duration of acute infectious events was reduced by five times after immunization (p = 0.0000001). Vaccination did not lead to disease flare: the number of patients with active joints decreased by half compared to the baseline, and the number of patients with systemic manifestations decreased by six times. All vaccine-associated adverse events were considered mild and resolved within 1–2 days. Conclusions: Simultaneous vaccination against pneumococcal and Hib infections in sJIA children is an effective and safe tool that reduces the number and duration of infectious events and does not cause disease flare-ups. Full article

Background: Lumpy skin disease (LSD) is major transboundary disease affecting cattle and water buffaloes, indirectly causing huge socio-economic losses. Following its first outbreak in India in 2019, the heterologous Goatpox (Uttarkashi strain) vaccine mitigated LSD. Objective: Due to limited data on the spatiotemporal distribution of the disease, this study investigates its dynamics and presents findings from a field study conducted in Maharashtra, India. This study evaluates the safety, immunogenicity, and duration of immunity provided by a heterologous vaccine. Additionally, it examines post-vaccination responses in relation to factors such as age, gender, and breed. Methods: This study employed spatiotemporal analysis of lumpy skin disease (LSD) outbreaks from 2020 to 2024 using GeoDa (v1.22), incorporating Moran’s I and Getis-Ord Gi* statistics to identify spatial clustering patterns. A randomized field trial was conducted to evaluate vaccine safety and immunogenicity in 657 cattle across seven districts. Humoral immune responses were assessed using the serum neutralization test (SNT) and indirect enzyme-linked immunosorbent assay (ELISA), while cell-mediated immunity was evaluated via Interferon-gamma (IFN-γ) ELISA. For sero-monitoring, a total of 1925 serum samples from 22 districts were analyzed. Additionally, statistical analyses (n = 1925), including the Kappa Index, ANOVA, and logistic regression, were performed using SPSS v27 to investigate the influence of factors such as age, sex, and breed (significance level: p < 0.05). Results: LSD exhibited significant spatial clustering across Maharashtra. The Goatpox vaccine was 100% safe, with no adverse reactions. Protective antibody titers (≥1:8) were observed in 96.9% of vaccinated cattle by 14–21 days post-vaccination (dpv), peaking at 60 dpv before declining at 150 dpv. The cell-mediated immune response peaked at 28 dpv. Clinical monitoring for one year showed that only 2% of vaccinated cattle developed mild LSD symptoms after nine months, with no mortality. At six months post-vaccination, seroconversion was 69.7%, with breed significantly influencing seropositivity. Conclusions: This study confirms the Goatpox vaccine’s safety and strong immunogenicity in cattle, marking its first large-scale evaluation in the Indian subcontinent. Further research is needed to assess long-term immunity and protection against virulent LSD strains. Full article

Zika and malaria are important vector-borne febrile illnesses in humans. In this study, we determined the circulation of Zika virus and malaria infections, their hotspots, and their predominant clinical features. A cross-sectional study was carried out in six Local Government Areas (LGAs) in Kaduna State, Nigeria, from September 2018 to May 2019. Four hundred and twenty sera were screened for Zika virus (ZV) IgM and IgG, and Plasmodium falciparum antigen using ELISA and immunochromatographic test, respectively. Overall, a seroprevalence of 14.5% was found for Zika, and 9.3% for malaria. Nineteen (4.5%) and thirty-five (8.3%) patients were seropositive for ZV IgM and IgG, respectively. Co-infection rates for Zika (ZV IgM) and malaria (0.5%: 2/420), and for ZV IgG and malaria (0.7%: 3/420) were observed. Lere (10%: 7/70 for ZV IgM), Kachia (14.3%: 10/70 for ZV IgG) and Zaria (18.6%: 13/70 for malaria) LGAs were identified as hotspots for Zika and malaria. Age was significantly associated with malaria (p = 0.008) and ZV IgG (p = 0.004). Patients aged 1–10 years had the highest malaria seroprevalence (18.4%), while those aged 21–30 years had the highest ZV IgM prevalence (6.1%: 7/114). Out of the pregnant patients (56/420) tested, 5.37% (3/56) had antibodies to both recent and past ZV infection. A significant association was found between maculopapular rash (p = 0.021) and Zika, as well as between duration of the fever and recent Zika infection (p = 0.041). We highlight that malaria is endemic in Kaduna and that ZV is silently circulating, providing baseline data for further molecular epidemiological studies. Full article

Background: Given the significant impact of population immunity on the measles epidemic, understanding immunity differences among populations with varying immunity backgrounds is necessary for identifying immunity gaps and informing vaccination policies. In this study, we aimed to determine the distinct dynamics of vaccine-induced and naturally acquired antibodies, with specific focus on difference in vaccine-induced antibody responses across different birth cohorts. Methods: Based on two cohorts and one cross-sectional study conducted in Anhua County, Hunan Province, China, serum samples from children who followed China’s routine measles vaccination schedule (i.e., two-dose schedule at 8/18 months) and adults who acquired immunity through natural infection were tested for measles IgG antibodies using an enzyme-linked immunosorbent assay. The generalized additive mixed model and a mechanistic model were employed to describe antibody dynamics following vaccination and infections. Wavelet analysis was used to investigate the temporal relationship between the measles epidemic and long-term antibody levels after natural infection. Results: A total of 408 children (0–12 years) and 222 adults (54–84 years) were included in the present study. Vaccine-induced antibody levels following 8 m/18 m vaccination were estimated to fall below the protective threshold of 200 mIU/mL by age of 15.8, whereas antibody levels following infections remained high. The decay rate of vaccine-induced antibodies was estimated at 3.0 × 10⁻³ log-log mIU/mL per year, whereas naturally acquired measles antibodies persisted lifelong with a significantly lower decay rate of 2.30 × 10⁻⁵ log-log mIU/mL per year. Moreover, vaccine-induced antibody levels in children born after 2010—a period of low measles incidence—declined more rapidly (duration of protective immunity: 12.5 years), compared to those born before 2010. Discussion: Our findings revealed immunity heterogeneity among individuals with difference measles immunity backgrounds. In particular, the birth-cohort specific differences in vaccine-induced immunity highlighted the key role of young generations born in settings with low measles incidence in contributing to population immunity gaps. This underlines that greater attention should be given to this group in future catch-up vaccination efforts. Full article