Evaluation of measles immunity in the central black sea region of Türkiye.

In 2010—2016, blood serum samples were examined from 5539 patients, aged 1—60 years, with clinically and laboratory confirmed measles. Primary or secondary type of immune response was determined for all measles cases. Studies were performed with children aged 1—14 years (2381), adolescents, 15—17 years old (189), and adults aged 18—60 years (2969). Serum measles-specific IgM antibodies were measured by “VektoKor’ IgM” ELISA test system (Russia), concentration and avidity of specific IgG — by using “Anti-Measles Viruses ELISA/IgG” and “Avidity: Anti-Measles Viruses ELISA/ IgG” (Euroimmun, Germany). Primary immune response was identified based on the presence of serum measles-specific low avidity IgM and IgG antibodies, whereas secondary immune response was characterized by detecting high avidity IgM and IgG antibodies at concentration of ≥ 5.0 IU/ml. Analyzing measles-specific IgM antibodies in 2010—2016 demonstrated that measles morbidity was mainly due to children, aged 1—2 years reaching up to 39.9% of the total number of children with measles aged 1—14 years as well as adults aged 18—40 years old comprising as high as 80.1% total number of patients aged 15—60 years. Serum measles-specific IgG testing showed that in 15.0% of cases they were detected at concentration of ≥ 5.0 IU/ml. Further serum dilution resulted in finding IgG titer ranging within 8.5—45.0 IU/ml (21.4+0.36) and high avidity antibodies in 80—100% (92.5+0.2) cases. The remaining 85.0% cases found low avidity measles-specific IgG antibodies ( 30%) at concentration of 0.2—3.46 IU/ml (1.73+0.03). An age-related analysis of our data demonstrated that all children under 14 with laboratory-confirmed measles developed primary immune response. Moreover, in 73.7% of measles patients aged 15—60 with primary immune response measles might be prevented by timely vaccination, whereas persons with “vaccine failure” comprised 26.3%. In 2010 (0.09 per 100,000 subjects) and 2016 (0.12 per 100,000 subjects), frequency of patients with “vaccine failure” during relative epidemic well-being was 35.3% and 18.2%, respectively, exceeding 9.9% (p 0.001) serving as a hallmark 2014 high measles incidence rate (3.24 per 100,000 subjects).The data obtained indicate that measles virus circulate among people with “vaccine failure,” which may account for potential to spread and infect unprotected population cohorts as well as cause measles outbreaks during periods of epidemic well-being.

We compared the use of serum and filter paper blood spots as specimen sources for the detection of measles- and rubella-specific IgM and IgG. We collected capillary blood into microtainer tubes and onto filter paper spots from 60 children and 60 healthy adults. The blood was collected from 12-15-month-old children approximately 3 weeks after primary vaccination with measles, mumps, rubella vaccine, and the sample-pairs were tested for measles-specific IgM and IgG antibodies by using a capture antibody EIA and an indirect EIA, respectively. We tested sample-pairs from a subset of participants for rubella- specific IgM and IgG antibodies by using commercially available capture IgM (Captia) and indirect IgG (Wampole) assays. The concordance of results from serum and filter paper blood spots was high for all assays: 98% for measles IgM, 93% for measles IgG, 94% for rubella IgM, and 93% for rubella IgG, and increased to between 96-100% for all four assays when indeterminate samples were excluded. The correlation coefficients for EIA signals were 0.99 and 0.77 for measles IgM and IgG, respectively, and 0.92 and 0.94 for rubella IgM and IgG, respectively. The cut-off values used for filter paper samples were the same as those used for serum samples for all tests except for the rubella IgM assay. The use of filter paper blood spots is a promising future option for the detection of measles- and rubella-specific antibodies.

Background: Measles is a highly contagious viral infection that can cause serious health problems. While measles can be eradicated through vaccination in our country and worldwide, in recent years, vaccine refusal, difficulties in accessing vaccines during the coronavirus disease 2019 (COVID-19) pandemic, and insufficient immunity in young adults have brought the “measles virus” back into the spotlight. The aim of this study was to compare ELISA results for measles IgM and IgG in samples from patients examined at our hospital in in 2024 who were suspected of having measles, with respect to variables such as age, gender, and season. Methods: In serum samples taken from patients with suspected measles who came to Kars Kafkas University Faculty of Medicine Medical Microbiology Laboratory, Measles IgG, measles IgM tests (Anti-Measles Virus IgM, Anti-Measles Virus IgG) were studied with kits of the same device in the Enzyme-Linked Immunosorbent Assay (ELISA) method, and the results were evaluated in line with the manufacturer’s recommendations. Results: In our study, 30 (63.8%) of 47 patients tested were seropositive for measles IgG antibodies. Measles IgM antibodies were detected in 2 (4.3%) of the 47 patients tested. One patient had intermediate values for both measles IgG and IgM. Conclusion: In our study, no significant relationships were found between age, gender, and season and the Measles IgG and IgM tests. In our study, 34% of the patients in Kars province with measles antibody responses were found to be susceptible to measles infection. Cite this article as: Balkan Bozlak ÇE, Uçar M, Çelebi ., Yılmaz A. Seropositivity status in patients with suspected measles: are we going back to the beginning with measles? 2026, 58(3), 1203, doi: 10.5152/eurasianjmed.2026.251181.

Despite adherence to the policy of mass measles vaccination in the majority of countries, this infection still remains far from being fully eradicated. Measles outbreaks are reported worldwide, when the vast majority of cases are recorded in subjects of 18—35 years of age. Studies on assessing measles IgG antibody level in different regions of Russia reveal increased percentage of measles seronegative subjects among young adults. Current study was aimed at investigating formation of humoral and cellular immunity after measles vaccination in seronegative adults aged 18 to 30 years old. There were enrolled 50 measles seronegative healthy volunteers aged 18 to 30 years old. Level of anti-measles IgM and IgG antibodies was measured by ELISA (Vector-Best, Russia). Subclasses of measles specific IgG antibodies were analyzed by ELISA, by replacing IgG conjugate for IgG1, IgG2, IgG3, IgG4 conjugates, whereas measles specific IgA antibodies were estimated by ELISA with IgA conjugate (Polygnost, Russia) at a concentration of 1 μg/ml. Antibody avidity was assessed by ELISA (Euroimmun, Germany). Cell-mediated measles immunity was estimated by CD107a surface expression on CD8hi T cell subset stimulated by measles virus-derived antigens. A specific cellular response to measles antigens before vaccination was detected in 50% of examined subjects, whereas 40% samples showed no signs of cellular immune response, with 10% of remaining cases described as equivocal. It was found that 6 weeks after vaccination all vaccinated subjects developed measles specific IgG antibodies at protective level reaching 1.33 (0.85—1.82) IU/ml [Me (LQ—UQ)]. Anti-measles IgA antibodies were of 0.655 (0.423—1.208) IU/ml [Me (LQ—UQ)]. However, no measles specific IgM antibodies were detected 6 weeks after vaccination. In addition, primary type of immune response (dominant low-avidity anti-measles antibodies IgG3 subclass) to measles vaccination was observed in 24 out of 50 subjects, whereas 26 subjects developed secondary type of immune response (high-avidity anti-measles antibodies dominated by IgG1 subclass). A measles specific cellular immune response was observed in 47 of the 50 examined subjects, and in 3 volunteers it was equivocal. Further analysis revealed a cohort of subjects who were not vaccinated against measles (18 subjects), although 60% of them provided medical record on previous dual measles vaccination occurred in childhood. Another cohort consisted of subjects who had medical record of measles vaccination in childhood (32 subjects), but lost protective measles antibodies produced by plasma cells (23 subjects), and memory T cells (3 subjects), or measles antibodies and memory B cells (6 subjects) over time. Such pattern evidences that measles-specific cellular and humoral arms immune responses were developed and maintained independently of each other.

Background: In recent years, Uzbekistan has faced a renewed challenge in controlling measles, with a noticeable rise in adult cases after the COVID-19 pandemic. While measles is typically regarded as a childhood disease, the infection in adults often follows a more severe course and is accompanied by frequent complications. The reduction in population immunity, combined with incomplete vaccination histories, has contributed to the re-emergence of measles among adults. Evaluating both the clinical presentation and serological immune response, particularly measles-specific IgG antibodies, is crucial for understanding current patterns of susceptibility. Objective: To describe the clinical and immunological characteristics of measles in adults in Uzbekistan during 2023–2025, with particular attention to disease severity, complications, and IgG antibody profiles. Methods: A prospective observational study was carried out at the 3rd clinic of Tashkent Me and several regional clinics. The study consisted of 187 adults aged 18–59 years with laboratory-confirmed measles. Diagnosis was based on characteristic clinical features and the detection of measles-specific IgM and IgG antibodies using enzyme-linked immunosorbent assay (ELISA). Each patient underwent a detailed clinical assessment and standard laboratory testing. IgG titers were measured at admission and again on days 10–14 to evaluate immune response and seroconversion. Results: Most patients were young adults (mean age 28.4 ± 9.7 years); 72 % reported no prior vaccination. Fever above 39 °C, cough, conjunctivitis, and generalized rash were the predominant symptoms. Complications developed in 37.9 % of patients, most often pneumonia, hepatitis, or gastrointestinal involvement. Laboratory findings commonly showed leukopenia and moderate elevation of liver enzymes. At admission, 26 % of patients had no significant measles-specific IgG, indicating susceptibility despite presumed prior exposure. Among those with paired sera, 84 % demonstrated a fourfold increase in IgG titers during convalescence, confirming an active immune response. Conclusion: Adult measles in Uzbekistan during the post-pandemic period was characterized by a moderate to severe clinical course and a high rate of complications. The detection of low IgG levels in a considerable proportion of patients highlights existing immunity gaps among adults. Incorporating IgG screening into routine epidemiological surveillance and extending vaccination programs to adults could help identify at-risk groups and strengthen measles control in the upcoming years.

Measles Virus IgG Avidity Assay for Use in Identification of Measles Vaccine Failures in Tianjin, China

Measles immunity status in Iranian infants and children and outbreak concerns: Time for reconsidering the vaccination schedule?

In the context of measles elimination, the identification of recent infections is important for clinical laboratories. Serological diagnosis is achieved by detecting specific IgG and IgM. Recently an automated chemiluminescent immunoassay (CLIA) (Liaison, DiaSorin, Italy) has been used to quantify the measles antibody. The aim of this study was to compare this assay with Enzygnost ELISA (Siemens, Germany), with final classification of discrepancies by indirect immunofluorescence (Euroimmun, Germany). For measles IgM, 204 sera were analyzed: 50IgM-positive, 104IgM-negative/IgG-positive, and 50 from other viral infections (B19V, rubella, mumps, CMV, and EBV). For the measles IgG assay, 162 samples were tested: 106 were positive and 56 were negative. For measles IgM, the sensitivity and specificity of CLIA against ELISA were 94% (95% CI: 83.2-98.6) and 100% (95% CI: 97.1-100), respectively; the corrected figures after the final classification of discrepancies were 100% (95% CI: 91.0-100) and 99.4% (95% CI: 96.1-100), respectively. In relation to IgG, the sensitivity and specificity of CLIA against ELISA were, respectively, 97.2% (95% CI: 91.7-99.4) and 92.9% (95% CI: 82.5-97.7), and 95.5% (95% CI: 89.5-98.3) and 100% (95% CI: 91.8-100) after the final classification. CLIA showed excellent sensitivity and specificity in detecting measles IgG and IgM antibodies, eliminating the need to aliquot specimens before carrying out the assay.

Measles is now rare in Australia, and cases can usually be linked to its importation from endemic countries. To prevent measles outbreaks in Australia, high vaccination coverage with two doses of vaccine must be sustained. All medical practitioners should consider a diagnosis of measles in a patient of any age who presents with fever and a non-vesiculating, non-itchy rash. If measles is suspected clinically, public health authorities should be immediately notified, so that testing and management of patients can be discussed and contact tracing initiated. When a patient is suspected of having measles, testing of a serum sample for measles-specific IgM and IgG antibodies should be requested urgently. Pathology laboratories should have effective protocols for immediately reporting positive measles-specific IgM antibody tests, or other results indicative of measles, to public health authorities.

Nowadays, the age group affected from measles has widened and the disease has become more common among adolescents and young adults. The number of measles case reports have increased in our country, particularly from 2010-2011, and measles outbreaks occurred in various regions in 2012 and 2013. The aim of this study was to analyze the demographical and epidemiological characteristics, clinical and laboratory findings, and complications of adult patients with measles who were affected during the outbreak. A total of 28 patients (25 male, 3 female; age range: 19-39 years, median age: 24) who were hospitalized and followed-up in our clinic between January 2013 and June 2013, were evaluated. In the serum sample of the index case, measles-specific IgM antibodies were detected by ELISA, and measles virus RNA by real-time polymerase chain reaction (RT-PCR), then genotyping was performed to detect the epidemiological relationship. In all of the other cases, measles IgM and IgG antibodies were screened by ELISA. The most common symptoms on admission included high fever (n= 28, 100%), malaise (n= 25, 89%), sore throat (n= 25, 89%), headache (n= 20, 71%) and cough (n= 18, 64%). At physical examination, rash (n= 28, 100%), lymphadenopathy (n= 11, 39%) and conjunctivitis (n= 10, 36%) were in the foreground, and Koplik spots were detected in five (18%) cases. The most common laboratory findings were; increased level of C-reactive protein (n= 15, 54%), leukopenia (n= 12, 43%) and increased serum levels of aminotransferases (n= 12, 43%), and thrombocytopenia was detected in five (18%) patients. One or more complications (secondary bacterial pneumonia in 5, diarrhea in 4, hepatitis in 3 and otitis in 2 cases) developed in the eight (29%) patients. Measles RT-PCR and IgM tests yielded positive results for the index case, and the isolate was identified as D8 strain by genotyping. Measles lgM antibodies were also positive in all of the other cases. The hospitalization period was estimated as 3-7 days (median: 5 days), while all the patients were discharged with recovery. It appeared that, our index case had come from a troop in Amasya province three days ago and he had a history of contact with suspected measles patients. In addition, the D8 strain determined in the index case was found to be related with the strain that caused the outbreak in Amasya province. Of the cases, 20 (71.4%) were military personnel, and eight (28.6%) were civilian who had histories of contact with military personnel. Regardless of immunity status in the outbreak period, all of the healthcare staff in our hospital, especially in risky departments, was recommended to be vaccinated. Personnel vaccination was provided at a high rate, however nosocomial transmission occurred in two unvaccinated cases. In conclusion, measles is an important health problem, especially in the adult age group, because of the complications and labour loss. For outbreak management; the awareness of health personnel should be increased following the identification of index case, proper isolation measures should be taken for the hospitalized patients, and routine reporting should be carried out timely and accurately.

Objective: To study the application of measles specific IgM and IgG antibody detection in classification of primary vaccination failure (PVF) and secondary vaccination failure (SVF). Methods: Measles surveillance information system was used to collect measles confirmed cases in Tianjin, 2013-2015, and their blood specimens were collected, totally 284 cases were enrolled. Measles IgM and IgG were detected with enzyme-linked immunosorbent assay (ELISA), and the relative avidity index (RAI) was used to express the result of measles avidity. Measles IgM, IgG and IgM/IgG was analyzed with receiver operating characteristic (ROC) curve, the area under the ROC curve (AUC) as evaluation indicators. In addition, compared with a measles outbreak (26 cases) of a middle school in Tianjin in 2016, for making further verification on the diagnostic value of vaccination failure with IgM, IgG and IgM/IgG. Results: The age of cases ranged was 0-58 years old, the interval median (P(25), P(75)) of serum collection after rash onset was 2 (1, 4) days. The positive rate of measles IgM and IgG in acute phase specimens were 76.06% (216 cases) and 88.38% (251 cases). According to the ROC curve analysis, the area under the ROC curve (AUC) of IgM, IgG and IgM/IgG were 0.753, 0.891 and 0.952, indicating that IgM/IgG was the best index to distinguish PVF and SVF. The best cut off value for IgM/IgG was 0.06, the sensibility and specificity were 88.75% and 86.63%. When IgM/IgG >1, 96.30% cases were low-avidity (RAI <40%), only 1 case was equivocal response (RAI: 40%-60%). 97.14% cases were high-avidity (RAI >60%) when IgM/IgG <0.01, only 3 cases were equivocal response (RAI 40%-60%). The threshold of IgM/IgG was used to verify the measles outbreak of a middle school in Tianjin, 2016. In the acute phase specimens, 100% (26 cases) of IgM/IgG were <0.06, 84.62% (22 cases) of IgM/IgG were <0.01. Conclusion: The detection of measles IgM and IgG with ELISA, and IgM/IgG is a valuable diagnostic tool to distinguish PVF and SVF.

Measles cases are increasing remarkably in our country as well as all over the world. In this study, it was aimed to examine the epidemiological and clinical characteristics of measles cases detected in our hospital, as well as the measles seroprevalence in our region. A total of 7,452 individuals whose measles IgG and/or IgM antibodies were studied between December 2021 and March 2023 in the Medical Virology Laboratory in Başakşehir Çam and Sakura City Hospital were included in this retrospective study. Measles IgG and IgM antibodies were analysed by enzyme-linked immunosorbent assay. Demographic information, clinical symptoms and laboratory data of the participants were obtained from the hospital's electronic medical records. A total of 102 measles cases were identified between December 2021 and March 2023. Of these cases, 77 (75.5%) patients were ≤ 18 years old. Of the 73 measles cases with vaccination information, 90% were unvaccinated. The measles seroprevalence rate was 72.8%. The lowest seroprevalence rate (4.8%) among the age groups was found in 8-11-month-old babies, the highest cases rate (35.7%) was detected in this age group. It was determined that measles immunity increased with age (r = 0.276, p < 0.001) and was over 89.3% over the age of 30. Measles immunity is insufficient in our region and measles remains an important public health problem until the age of 18. The recent increase in measles cases in our country and around the world shows that current vaccination programmes need to be implemented more decisively and strictly.

Detection of IgM antibodies specific for measles virus by capture and indirect enzyme immunoassays

Background:Limited information is currently available regarding the global incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections prior to the declaration of the coronavirus disease 2019 (COVID-19) pandemic, which may result in improper conclusions regarding the timing of viral transmission.MethodsWe investigated the presence of specific antibodies against the receptor-binding domain (RBD) of SARS-CoV-2 in archived serum samples that were collected from 478 healthy blood donors and patients in Madinah, Saudi Arabia, between October 2019 and January 2020. Enzyme-linked immunosorbent assay (ELISA) was performed to measure SARS-CoV-2 IgM and IgG antibodies. In addition, rheumatoid factor (RF) and urea dissociation tests were performed in all samples, which showed seropositivity for the SARS-CoV-2 IgM antibody. Additionally, Chemiluminescence immunoassays (CLIA) targeting the RBD of the SARS-CoV-2 spike (S) protein were performed to confirm the seropositivity of the samples.ResultsOverall, 20 (4.18%) serum samples were detected by ELISA to have SARS-CoV-2 IgG or IgM antibodies. Of these, 12 (2.51%) samples were positive for IgM antibody, and 8 (1.67%) were positive for IgG antibody. The 12 samples positive for SARS-CoV-2 IgM antibody were subjected to RF and urea dissociation tests, and all samples were RF-negative. The ELISA results were negative for 7 (58.33%) samples when subjected to urea dissociation prior to ELISA, whereas the other 5 (41.67%) samples remained positive. These 5 samples remained positive for the anti-S RBD IgG antibody in the CLIA. In addition, 3 of the 8 samples with IgG positivity according to the ELISA remained positive in the CLIA. After reviewing their data, we discovered that the 8 CLIA-confirmed positive samples were obtained from returned travellers who had visited China during the 4-week period immediately preceding blood donation.ConclusionIn conclusion, we found evidence to support the early circulation of SARS-CoV-2 among persons who visited China a few months prior to the pandemic declaration. These results can be used to better define the spread of SARS-CoV-2 infections before the COVID-19 pandemic declaration. The detection of SARS-CoV-2 antibodies in individuals before the pandemic was declared in China could rewrite the pre-pandemic timeline.

Background: Measles remains a significant occupational hazard in healthcare settings. In the context of the 2017–2018 measles outbreak in Greece and amid an outbreak at the study hospital, this seroprevalence study aimed to identify gaps in measles serologic status among healthcare workers in a tertiary hospital in central Greece. Methods: We conducted a seroprevalence study among hospital employees between February and December 2017. Blood samples and data on sociodemographic and work-related characteristics were collected from a convenience sample of participants. Measles IgG and IgM antibodies were measured using the ELISA method to determine seropositivity. The 95% CIs for measles IgG seronegativity proportions were calculated using the Clopper–Pearson exact method. Associations between participant characteristics and measles antibody status were assessed using Firth’s penalized logistic regression models. Results: A total of 336 healthcare workers participated in the study (response rate: 24.9%). Overall, 5.4% (95% CI: 3.2–8.3) tested negative for measles IgG antibodies. No significant associations were observed between participants’ characteristics and measles IgG antibody status. Male participants had 15.8 times higher adjusted odds of testing positive for measles IgM antibodies compared with female participants (aOR: 15.8; 95% CI: 2.33–107.54; p = 0.005). Conclusions: Our results indicate a low—but not negligible—proportion of IgG measles seronegativity among participants. The detection of seronegative individuals born prior to 1970 challenges the assumption of universal natural immunity based solely on year of birth. Given the recent rise in measles outbreaks and the limited seroprevalence data among healthcare workers in Greece, these findings provide valuable data to support ongoing efforts to achieve full vaccination coverage in this group. Further research is warranted to investigate the observed sex differences in susceptibility to measles infection.