Search Results (146)

Background: High national MMR coverage in Saudi Arabia coexists with sporadic measles, mumps, and rubella cases. Local data are needed to describe vaccination coverage among the reported cases and patterns of laboratory-confirmed infections. Objectives: This study was conducted to describe MMR vaccination coverage among the reported suspected cases and patterns of laboratory-confirmed measles, mumps, and rubella in Al-Baha, Saudi Arabia, from January 2020 to August 2024, and to examine associations between demographics, residence, vaccination status, and case classification. Methods: We conducted a retrospective analysis of surveillance records from the Al-Baha Communicable Disease Reporting System. We summarized the demographics, vaccination history, and final classification for 295 reported suspected cases. Inferential analyses (chi-square and logistic regression) used laboratory-confirmed cases only. Statistical significance was p < 0.05. Results: Of 295 reported suspected cases, 239 (81.0%) were discarded after investigation, and 52 (17.6%) were confirmed (including 50 laboratory-confirmed and two epidemiologically confirmed), with 3 (1.0%) remaining under review at analysis. Among all reported cases, the vaccination status was ≥2 doses, 57.6% (n = 170), one dose, 19.0% (n = 56), and unvaccinated/unknown, 23.4% (n = 69). Among the laboratory-confirmed infections, measles was clustered in unvaccinated/unknown, mumps was clustered in single-dose recipients, and rubella was in ≥2-dose recipients. In multivariable models, males had higher odds of a laboratory-confirmed infection, and rural residence was associated with increased odds. The confidence intervals were wide due to small numbers. Conclusions: Reported surveillance data show persistent laboratory-confirmed MMR infections in Al-Baha with demographic and geographic disparities. The findings support targeted efforts to complete two-dose schedules, strengthen rural access, and improve immunization record systems. The results are associations and not causal measures of vaccine effectiveness, and should be interpreted in light of small confirmed case counts. Full article

Background: Children with inflammatory bowel disease (IBD) are at heightened risk for vaccine-preventable infections because of underlying immune dysregulation and long-term immunosuppressive therapy. Despite published guidelines affirming vaccine safety, real-world coverage remains suboptimal. It is a pilot, single-country survey designed to explore baseline knowledge and practices regarding vaccination in paediatric IBD within a specific local healthcare context. Objective: The objective of this study is to evaluate the knowledge, attitudes, and practices of paediatric gastroenterologists (PGs) regarding the immunisation of children with IBD. Methods: We conducted an exploratory pilot, cross-sectional survey of paediatric gastroenterologists in Russia, focusing on immunisation knowledge and practical barriers in routine care. A cross-sectional, anonymous online survey was distributed to PGs nationwide between January 2022 and April 2022. The online questionnaire explored demographic characteristics, awareness of international recommendations, perceptions of vaccine safety at various disease and treatment stages, and routine vaccination practices. Responses were analysed with non-parametric statistics (α = 0.05). In a parallel prospective cohort, the vaccination certificates of 98 paediatric IBD patients (January 2022–April 2023) were audited to quantify real-world coverage. Results: Fifty-one PGs completed the survey. Forty-one per cent agreed that vaccines do not provoke IBD flares, while 17.6% considered live vaccines acceptable during immunosuppressive remission. Nearly one-third (32%) did not personally oversee immunisation, and 18% occasionally discouraged vaccination during therapy. Only 35.3% deemed baseline serology essential before starting immunosuppression; 46.5% supported antibody checks immediately prior to vaccination. The certificate audit revealed a full schedule completion rate of 66.3% for measles–mumps–rubella and 74.2% for hepatitis B, contrasting with parental reports of 82.3% complete coverage. Conclusions: Knowledge gaps, limited guideline awareness, and parental concerns contribute to suboptimal vaccination of paediatric IBD patients. Targeted educational initiatives, clearer shared-care pathways, and routine certificate audits are needed to close the coverage gap and reduce infection-related morbidity. Findings are hypothesis-generating and reflect local practice; as a pilot study, results should be interpreted with caution and may not generalise beyond similar settings. Full article

Background/Objectives: This study aimed to develop a new attenuated live mumps vaccine strain and determine its biological properties and effectiveness. Methods: Plaque purification and amplification were performed in chicken embryo cells. Candidate live attenuated mumps MuV-365 strain sequencing was performed. After evaluating the potential neurotoxicity of the MuV-365 mumps strain, a preclinical safety evaluation of measles–mumps–rubella (MMR) live attenuated vaccine containing the MuV-365 strain was performed to support the registration and application of the MMR vaccine. Finally, mumps neutralization antibody titers and the concentration of anti-serum mumps-specific IgG were determined to evaluate the immunogenicity and efficacy of the MuV-365 strain and MMR vaccine in mice and rhesus monkeys. Results: The plaque of the PL-KUM main seed virus was screened, and strains whose sequences were highly homologous to RIT4385 (JL-5 derived) were selected to amplify. The candidate live attenuated mumps MuV-365 strain was then developed. Safety evaluation results indicated that the MuV-365 strain had no potential neurotoxicity, and the MMR vaccine containing the MuV-365 strain also showed no significant safety hazard. The immunogenicity of MuV-365 strain in BALB/c mice was not inferior to S79 and PL-KUM. After two doses of the MuV-365 strain, the concentration of anti-serum mumps-specific IgG of the MuV-365 strain was significantly higher than that of the S79 strain (p < 0.01). In rhesus monkeys, the MMR vaccine had good immunogenicity against measles and rubella after one dose, while immunogenicity against mumps improved after two doses. Conclusions: The developed MuV-365 strain was genetically stable, with adequate safety and immunogenicity. Full article

Background: Despite virological suppression through antiretroviral therapy (ART), people living with HIV (PLHIV) may exhibit inadequate immune responses to vaccination, placing them at continued risk for preventable infectious diseases. Evidence regarding the durability of vaccine-induced immunity in PLHIV with vertically acquired infection remains limited. Methods: We conducted a cross-sectional observational study to evaluate humoral immunity to routine childhood vaccines in a cohort of PLHIV with perinatally acquired infection. Antibody titers against diphtheria, tetanus, measles, mumps, rubella, varicella, and hepatitis B (HBV) were retrospectively assessed via serological testing and review of medical records. Seroprotection rates were analyzed at predefined intervals following the completion of the primary immunization schedule. Multivariate analysis was used to explore potential predictors of long-term immune response. Results: A total of 85 individuals were included. Two years after completing the primary vaccination series, seroprotection rates were as follows: diphtheria 71%, tetanus 79%, measles 79%, mumps 67%, rubella 87%, and varicella 54%. Five years post-vaccination, 50–70% of participants maintained protective antibody levels, declining further to 50–58% after ten years. By twenty years, protective immunity dropped below 30% for all antigens except rubella (47%). HBV vaccine responses were notably poor, with only 60%, 37%, 24%, and 7.5% retaining protective anti-HBs titers at 2, 5, 10, and 20 years post-immunization, respectively. Time elapsed since vaccination was the sole significant predictor of seroprotection across all vaccines. Conclusions: In this cohort of vertically infected PLHIV, vaccine-induced immunity was suboptimal and declined markedly over time compared to the general population. These findings highlight the need for tailored immunization strategies, including timely boosters and regular serological monitoring, to maintain long-term protection in this high-risk group. Full article

Background and Objectives: Romania has experienced the highest measles incidence rate in the European Union since late 2023, driven by suboptimal measles–mumps–rubella (MMR) uptake. Contemporary data on bedside predictors of clinical deterioration are scarce. The objective was to characterise demographic, clinical and laboratory differences between severe and non-severe measles and derive a multivariable model for intensive-care-unit (ICU) admission. Methods: We undertook a retrospective cohort study at the “Victor Babeș” University Hospital for Infectious Diseases, Timișoara. All admissions from 1 November 2023 to 15 May 2025 with serological or RT-PCR confirmation and a complete baseline laboratory panel were included. Descriptive statistics compared ward-managed versus ICU-managed patients; independent predictors of ICU transfer were identified through logistic regression that incorporated age, vaccination status, leukocyte count, C-reactive protein (CRP) and interleukin-6 (IL-6). Results: Among 455 patients (median age 3.0 y, interquartile range [IQR] 1.0–7.0), 17 (3.7%) required ICU care. Vaccine coverage was 18.0% overall and 0% among ICU cases. Compared with ward peers, ICU patients exhibited higher leukocyte counts (8.1 × 10⁹ L vs. 6.0 × 10⁹ L; p = 0.003) and a near-five-fold elevation in IL-6 (18 pg mL vs. 4 pg mL; p < 0.001), while CRP, procalcitonin and fibrinogen were similar. ICU admission prolonged median length of stay from 5 days (IQR 4–7) to 8 days (5–12; p = 0.004). In multivariable modelling, IL-6 remained the sole independent predictor (odds ratio [OR] 1.07 per pg mL; 95% confidence interval [CI] 1.03–1.12; p = 0.001); the model’s AUC was 0.83, indicating good discrimination. Complete separation precluded reliable estimation of the protective effect of vaccination, but no vaccinated child required ICU care. Conclusions: A simple admission panel centred on IL-6 accurately identified Romanian measles patients at risk of critical deterioration, whereas traditional markers such as CRP and leukocyte count added little incremental value. Even a single documented MMR dose was associated with the complete absence of ICU transfers, underscoring the urgent need for catch-up immunisation campaigns. Integrating IL-6-guided triage with intensified vaccination outreach could substantially reduce measles-related morbidity and health-system strain in low-coverage EU settings. Full article

Background/Objectives: Measles, mumps, and rubella (MMR) continue to pose a significant public health challenge due to insufficient immunization coverage. This study aimed to provide the first seroprevalence data against MMR and to explore self-reported immunity among future healthcare workers (HCWs) in Serbia, including women of childbearing age. Methods: We included 1296 future health care workers (HCWs) aged 19 to 29, born in Serbia. All HCWs supplied a blood sample for serology and filled in a questionnaire. Antibodies were measured using an enzyme immunoassay against measles, mumps, and rubella (MMR). Results: Anti-measles, -mumps, and -rubella seronegativity rates were 25.6%, 26.5%, and 4.4%, respectively, among future HCWs in Serbia. The mumps seronegativity rate was significantly higher in the oldest (27–29-year) age group, accompanied by significantly lower anti-mumps IgG GMCs in the same age group compared to younger participants (p = 0.035 and p < 0.001, respectively). Anti-mumps seronegativity also increased significantly across birth cohorts, from the youngest to the oldest (p = 0.004). Furthermore, anti-mumps IgG antibody GMCs were significantly higher among females, those who attended nursery/kindergarten, and unvaccinated individuals (p = 0.050, p = 0.020, and p = 0.005, respectively). Finally, older age and unvaccinated status were identified as independent factors associated with anti-measles and anti-mumps seronegativity among future HCWs in Serbia. Conclusions: The cross-sectional seroprevalence data revealed insufficient seroprotection in this population of particular importance, i.e., future HCWs, and women of childbearing age. These results strongly support the national recommendations for the mandatory vaccination of these populations. Identified immunity gaps should be closed promptly by strategic, targeted serologic screening, followed by vaccination of those lacking MMR antibodies. Full article

Background/Objectives: In the Republic of Serbia, measles vaccination was first introduced in 1971, while combined vaccination (measles, mumps, rubella) was made mandatory in 1996 as part of the national vaccination program. Reported prevalence values for 2023 were <0.75 cases per 100K population for measles, 0.09 cases per 100K for mumps, and no cases of rubella. Methods: This cross-sectional study was performed in May, 2024 as part of the project “Herd Immunity to Vaccine-Preventable and Other Relevant Infections in the Belgradian Population.” It focused on assessing herd immunity to measles, mumps and rubella (MMR) among residents insofar as these remain a public concern despite the availability of vaccines. A total of 2533 subjects were distributed across nine age groups, covering those aged 1–70⁺ years and various professional groups residing in Belgrade. Participants were stratified by age and activity. Upon obtaining individual information by online questionnaire and receiving a signed statement of informed consent, blood samples were obtained for IgG antibody testing (ELISA) to determine MMR serological status. The results were compared to national and international immunization standards to evaluate herd immunity levels. Results: Our results indicate varying levels of immunity for each virus, with specific demographic groups showing different immunity levels. Total measles seroprevalence during this study was 74.7%, with significant variation across all age groups. While high seropositivity was observed in both children (90.7%) and elder age groups (98.4%), middle-aged individuals in the age group 30–49 years showed significantly lower IgG levels. Between 2021 and 2023, there were no registered cases of rubella detected in Serbia, which indicates a high level of immunity. This was confirmed here with consistently high IgG levels across all age groups, with an average seropositivity of 94.8%. Average mumps seropositivity across all age groups was 85.1%. The lowest value was in the young child (1–5 years) age group (76.1%); the highest was in the elderly group (92.6%). Conclusions: The current findings suggest that the Belgradian population has strong overall immunity to MMR, yet with some concerns regarding measles immunity in middle-aged adults, suggesting a potential need for catch-up vaccinations. While rubella status indicates strong herd immunity and minimal risk of outbreaks, mumps immunity in some groups (children, middle-aged adults) is below the protective threshold. While it is still sufficient to prevent widespread transmission, it should be closely observed. To our knowledge, this study is the first of its kind to provide data about MMR seroprevalence in Belgrade. Findings indicate the need for constant surveillance and revaccination of vulnerable/seronegative groups. Full article

Background: Newly arrived migrants are at increased risk for vaccine-preventable and communicable diseases due to low immunization coverage, poor access to healthcare, and challenging migration trajectories. This study describes the implementation and outcomes of a one-stop public health intervention focused on serological screening and accelerated vaccination in recently arrived migrants in Galicia, Spain. Methods: We conducted a cross-sectional descriptive study in July and August 2024 involving 335 adult migrants from sub-Saharan Africa with irregular administrative status and asylum applications. A centralized mobile health unit provided point-of-care screening for immunity against measles, mumps, rubella, varicella, and hepatitis A, alongside testing for active infections, including hepatitis B and syphilis. Sociodemographic and clinical data were collected, and individuals were offered vaccination according to an accelerated immunization schedule. Results: Of 336 migrant adults invited to participate in the study, only 1 individual declined to participate (participation rate: 99.7%). Therefore, 335 migrants were assessed. A significant proportion of participants were susceptible to at least one vaccine-preventable disease, particularly hepatitis B (36.4%, 95% CI 31.3–41.6), measles (22.7%, 95% CI 18.2–27.2), and varicella (16.4%, 95% CI 12.5–20.4). Active infections were detected in 12.9% (95% CI 9.3–16.4) of individuals, including hepatitis B (9.9%, 95% CI 6.7–13.0) and syphilis (3.0%, 95% CI 1.2–4.8). The intervention allowed for timely vaccination and linkage to care, minimizing dependence on passive healthcare access. Conclusions: This study highlights substantial immunization gaps and the presence of undiagnosed infections in vulnerable migrant populations. Centralized and culturally adapted screening programs, combined with accelerated vaccination strategies, are feasible and effective. These findings support the integration of structured protocols into national health systems to ensure equity, reduce transmission risk, and align with WHO and ECDC public health frameworks. Full article

Cutaneous warts caused by human papillomavirus (HPV) are among the most common dermatological conditions, affecting the quality of life of numerous people. Although they are widespread, effective and reliable treatment alternatives are limited, emphasizing the necessity for novel treatment options. Intralesional immunotherapy has emerged as a promising alternative, aiming to stimulate the host immune response to achieve the clearance of both treated and distant lesions. This review explores the immunopathogenesis of cutaneous warts and provides an in-depth analysis of intralesional therapies including measles–mumps–rubella (MMR) vaccine, purified protein derivative (PPD), Bacillus Calmette–Guérin (BCG), Candida antigen, Mycobacterium w vaccine (MWV), vitamin D3, and autoinoculation. We provide a comprehensive analysis of the most promising modalities, highlighting their mechanism of action, outcomes, advantages, and limitations. Although initial data indicate that intralesional immunotherapy offers advantageous efficacy and tolerability, there is a lack of standardized treatment protocols and randomized controlled trials to endorse its broad application. Nevertheless, considering its potential to address local and distant lesions with minimal adverse effects, intralesional immunotherapy may represent a transformative approach to managing cutaneous warts. Full article

Background: Chemotherapy, a cornerstone treatment for Acute Lymphoblastic Leukemia (ALL), can compromise immune function, leading to impaired immune memory function and diminished responses to revaccination. This systematic review and meta-analysis sought to evaluate the impact of chemotherapy on the immunogenicity of prior vaccinations and subsequent revaccination responses in children with ALL. Methods: A comprehensive search was conducted through PubMed, Embase, Web of Science, and Medline. Search time was 9 January 2025. R 4.4.2 was employed for data analysis. Results: A total of 29 relevant studies were identified, with 8 undergoing meta-analysis. The pooled antibody seropositive rates (SPR) for vaccines against Hepatitis B Virus (HBV), Hepatitis A Virus (HAV), diphtheria, tetanus, pertussis, measles, mumps, rubella, varicella, and Pneumococcal Conjugate Vaccine (PCV) demonstrated a statistically significant decline after chemotherapy in ALL patients (p < 0.0001). Subgroup analysis further revealed marked and heterogeneous declines in SPR after chemotherapy, with the magnitude of reduction varying significantly across vaccines—tetanus, HBV, HAV, measles, mumps, and rubella (Subgroup differences, p = 0.0037). Conclusions: This review provides an updated assessment of this critical topic, representing the first meta-analysis specifically focused on the effects of chemotherapy on different vaccines’ immunogenicity in children with ALL. Full article

Background/Objective: Variations in measles vaccine antibody response by age and HIV status have been reported. This study assessed measles pre-vaccination status and compared humoral response durability over the first five years of life among HIV-infected (HI) children on early treatment, HIV-exposed uninfected (HEU), and HIV-unexposed uninfected (HUU) children within the ANRS 12225—Pediacam III cohort in Cameroon. Methods: Measles vaccine (MCV) was administered at 6 and 9 months for HIV-exposed infants and at 9 months for HIV-unexposed infants, followed by a measles-mumps-rubella (MMR) dose at 15 months for all. Measles antibody titers were measured pre-vaccination, 1–6 months post-MCV doses, and annually until age 5 using ELISA (Enzygnost, Dade Behring). Results: A total of 496 children were included: 143 HI (median age at cART initiation: 4.2 months, (IQR: 3.2–5.6)), 180 HEU, and 173 HUU. Of these, 456 children were tested pre-vaccination (median age: 6.1 months, IQR: 5.6–6.8), with 6.1% (95% CI: 4.1–8.6) seropositive to measles antibodies, with differences across groups. At 18.4 months (IQR: 18.1–19.9), seropositivity rates were 96.7% (59/61) in HI, 96.8% (90/93) in HEU, and 100% (111/111) in HUU groups. For children following the 6 + 9 + 15-month or 9 + 15-month MCV schedules, seropositivity at 18, 36, 48, and 60 months was 96%, 89%, 87%, and 88%, respectively, with no significant differences between groups. Conclusions: Early cART initiation in HI children may result in a robust initial measles antibody response, with comparable persistence of antibody titers across all groups up to five years. Full article

Objectives: Our objectives were to evaluate the safety of the simultaneous vaccination of Japanese encephalitis attenuated live vaccine (JEV-L) and measles, mumps, and rubella combined attenuated live vaccine (MMR) in children and to provide a reference for the implementation of the strategy of simultaneous vaccination with the two vaccines. Methods: The data of adverse events following immunization (AEFI) and vaccination for JEV-L and MMR from 2020 to 2023 were extracted through the Guangdong Province Vaccine Distribution and Vaccination Management Information System and the Chinese National AEFI Information System (CNAEFIS). The inclusion criteria were that children were born after 1 October 2019, and received the first dose of JEV-L or MMR after 1 June 2020, in accordance with the starting age for vaccination (8 months). The study used the number of vaccine doses as the denominator to calculate and compare the reporting rates of cases and calculated the relative risk (RR) of adverse reactions and the 95% confidence interval (CI). Results: In Guangzhou, a total of 214,238 doses of JEV-L were administered to children. JEV-L and MMR were co-administered in 464,009 doses, and MMR was administered separately in 241,150 doses. The overall reporting incidence rates of AEFI (per 100,000 doses) for JEV-L, the simultaneous vaccination group, and MMR were 11.20, 53.02, and 60.96, respectively. Among children aged 8 months in Guangzhou, 57.98% (463,512/799,423) received the simultaneous administration of JEV-L and MMR. In the reported AEFI events, general reactions accounted for 87.50% in the JEV-L group, 88.21% in the simultaneous vaccination group, and 89.80% in the MMR separate group. The incidence rates of common adverse reactions were 9.80, 46.7, and 54.74, respectively. The incidence rates of rare adverse reactions were 0.93, 3.88, and 2.90, respectively. The reporting incidence rates of fever ≥38.6 °C after vaccination were 4.20, 16.16, and 17.83 for the JEV-L separate group, simultaneous vaccination group, and MMR separate group, respectively. There was a significant difference between the simultaneous vaccination group and the JEV-L separate group (RR = 3.848, 95% CI = 1.927, 7.683), while no significant difference was found compared with the MMR separate group (RR = 0.906, 95% CI = 0.623, 1.318). The simultaneous vaccination group showed no significant differences in the reporting incidence rates of local redness and induration compared with the two separate vaccination groups (RR = 1.385, 95% CI = 0.144, 13.315; RR = 0.390, 95% CI = 0.087, 1.743; RR = 0.520, 95% CI = 0.033, 8.314). No significant differences were found in the incidence rates of rare adverse reactions such as maculopapular rash, urticaria, and thrombocytopenic purpura. Conclusions: The AEFI reporting incidence rate for the first dose of the simultaneous vaccination of JEV-L and MMR in 8-month-old children in Guangzhou is between the rates of the two separate groups. Compared with the MMR separate group, the simultaneous vaccination group does not increase the risk of adverse reactions. Full article

Background/Objectives: This study analyzed data on the actual timing of the first and second doses of the Measles, Mumps, and Rubella (MMR) vaccination in Slovakia according to the vaccination schedule. Methods: Histograms were constructed using immunological survey data on MMR vaccination conducted in Slovakia in 2018. Results: For the first dose (2560 individuals), 83.4% of them were vaccinated timely (15th–18th month, mostly in the 16th month), while 13.8% of them were delayed. For the second dose (1061 individuals), 72.7% of vaccinations were timely (11th year), and 23.2% were delayed. There was a bimodal distribution of the timing of the administration of the second dose, with peaks at the beginning of the 11th year and at the turn of the 11th and 12th year. Conclusions: The unexpected shape of the histograms suggests that ambiguous interpretations of the vaccination schedule may be one of the causes of vaccination delays. Full article

Background: This paper investigates the long-term effects of the measles, mumps, and rubella (MMR) vaccine on healthcare, education, and economic outcomes using a novel dataset from the Copenhagen School Health Records Register. Methods: To address potential endogeneity, we use within-sibling variation in vaccination status induced by different periods of vaccine availability in Denmark. Results: Our findings reveal that, prior to the establishment of herd immunity, vaccinated cohorts experienced substantial protection against hospitalizations related to MMR. During the same period, we also observe modest improvements in educational outcomes and positive—though statistically insignificant—estimates for labor market outcomes among siblings with discordant vaccination status. We find no impact of vaccination on hospitalizations, education, or economic outcomes for cohorts born after herd immunity was established, a period when everyone benefited from herd protection regardless of individual vaccination status. Conclusions: MMR vaccination, before herd immunity, reduced hospitalization due to Measles, Mumps, and Rubella. The impact on later outcomes, such as education, income, and employment lacks statistical precision at conventional levels. Evidence suggest positive self-selection in vaccination among families with high socioeconomic status. Full article

Specific prevention of measles, mumps, and rubella (MMR) is the main prerequisite for a radical reduction in the incidence of these infections in the Kyrgyz Republic (KR). An increase in the number of seronegative individuals observed in recent years has led to an increase in measles incidence. This is directly related to a decrease in collective immunity, which provides protection for the population only in conditions of a high density of immunized individuals and their uniform distribution in the population. The only way to estimate the number of immunized individuals is by conducting serological surveys of collective immunity. Aim of the study: The aim was to study the level of collective immunity to the MMR viruses in the KR. Materials and methods: This study involved a cohort of 6617 residents (volunteers) aged 1 to 70⁺ years, formed in accordance with the Rospotrebnadzor program “Assessment of collective immunity to vaccine-preventable and other relevant infections” and stratified by age and region of residence. During the study, participants filled out a questionnaire and gave venous blood samples to determine IgG antibodies to MMR viruses (ELISA using certified Russian test systems). Results: In December 2023, collective immunity ensured epidemiological well-being only with respect to rubella. The volunteer seropositivity was 94.2% (95% CI: 93.7–94.8). The average measles seropositivity was 78.9% (95% CI: 77.9–79.9). It was significantly lower in children aged 1–17 years and significantly higher than the cohort average in individuals aged ≥18 years. The average mumps seropositivity was 76.4% (95% CI: 75.3–77.4), with the minimum level noted among individuals aged 12–29 years (63.8%; 95% CI: 61.4–66.2). The maximum levels of mumps seropositivity were noted among children aged 6–11 years and older adults who had likely experienced mumps (50–70⁺ years). Seroprevalence distributions by activity correlated with age distributions (all infections). Conclusions: The system of targeted prophylaxis of vaccine-preventable infections adopted in the KR has contributed to the formation of a high level of rubella collective immunity and, to a lesser extent, measles and mumps immunity. The recent trend towards increases in measles and mumps incidence in the KR requires additional efforts to increase collective immunity to these infections. Full article