Sero-epidemiological study in prediction of the risk groups for measles outbreaks in Vojvodina, Serbia

Measles Immunity Status of Greek Population after the Outbreak in 2017-2018: Results from a Seroprevalence National Survey

Accurate data on susceptibility rates against measles in the general population of Greece are scarce. Many studies have estimated the vaccination coverage, but none have calculated the nationwide immunity rate, including all age groups, against the measles virus. The purpose of our study was to determine the measles immunity status, especially after the latest outbreak in 2017-2018. In total, 3972 leftover blood samples were obtained during 2020-2021. They were collected from a nationwide laboratory network using a geographically stratified sampling strategy and were tested for the presence of measles-specific IgG antibodies. The overall crude seroprevalence was calculated to be 89.6% and the adjusted was 89.8% (95% CI: 88.8-90.8%). There was no statistically significant difference in seropositivity between sexes (p = 0.783). Higher immunity rates and antibody concentrations were found in older age groups ≥41 years old (94.9%, 95% CI: 93.7-95.9%, and 730.0 mIU/mL) in comparison with younger individuals aged 1-40 years old (83.4%, 95% CI: 81.6-85.7%, and 616.5 mIU/mL). Comparing the seroprevalence among the Nomenclature of Territorial Units for Statistics (NUTS 2), a statistically significant difference was estimated among them (<0.001). The two regions where higher measles incidence was observed during the 2017-2018 outbreak, Eastern Macedonia and Thrace, and Western Greece, were among the four regions with lower seropositivity (84.6%, 95% CI: 79.9-89.4%, and 85.9%, 95% CI: 81.4-90.4%, respectively). Our study showed a measles immunity gap that affects the younger age groups and makes a new measles outbreak likely. The enforcement of vaccination campaigns and addressing vaccine hesitancy could bridge it and achieve the required target of herd immunity.

Effectiveness of Mandatory and Incentive-Based Routine Childhood Immunization Programs in Europe: A Systematic Review of the Literature

There is a lack of comprehensive and systematic data and evidence regarding the effectiveness of mandatory and incentive-based vaccination schemes. The results of such programs in some countries have not been adequately studied. A number of countries have recently introduced tightening vaccination measures, and it is important to analyze and assess the results of these programs. The unprecedented situation due to the COVID-19 pandemic and mass vaccination made the topic of the effectiveness of vaccination policies and mandates even more relevant. The aim of the study is to assess childhood vaccination programs implemented in selected countries. The study focuses on initiatives implemented in the European Region of the World Health Organization (WHO). A total of 466 full-text articles were assessed for eligibility, and 26 articles on seven countries were included in the synthesis. Additionally, we obtained and performed an analysis of data on the impact of COVID-19 on vaccine coverage and incidence of vaccine-preventable diseases, and the implementation of vaccine mandates in the selected countries. The evidence collected and analyzed in this review allowed us to conclude that the introduction of children routine vaccination mandates increases vaccine coverage and reduces the incidence of vaccine-preventable diseases when compared to the situation before the introduction of the mandates.

Measles outbreak, Montenegro January-July 2018: Lessons learned

In 2017, the Regional Verification Commission for Measles and Rubella Elimination (RVC) of the World Health Organization confirmed that measles elimination was sustained in Montenegro, and the previous endemic transmission remained interrupted. However, the RVC was extremely concerned over the continuing low vaccination coverage reported for this country. In this study, we describe the most recent measles epidemic in Montenegro using the epidemiological data collected from January 1 to July 31, 2018. The outbreak is largely attributable to a dangerous accumulation of susceptible subjects across the country and represents a high‐risk factor for re‐establishing endemic transmission in the Balkan area. This study showed how a vaccine‐preventable communicable disease outbreak can have a dramatic impact and severe consequences on regional public health system performance in terms of the sanitary spending point of view. A detailed update is provided on the epidemiological situation in this Central European area, not available until now.

On 2017, the Regional Verification Commission for Measles and Rubella Elimination (RVC) of World Health Organization confirmed that measles elimination was sustained in Montenegro, and the previous endemic transmission remained interrupted.

The reduction in vaccination coverage was one of the main causes of the measles outbreak in Montenegro in 2018: this report provides information on the impact of the epidemic on the national health service and complements the gap in epidemiological data on measles trends available for this country of the WHO European Region.

Seroprevalence of Measles-, Mumps-, and Rubella-specific antibodies in the German adult population - cross-sectional analysis of the German Health Interview and Examination Survey for Adults (DEGS1)

BACKGROUND

The WHO European Region targets the elimination of measles, rubella, and the congenital rubella syndrome and welcomes mumps elimination via the joint MMR vaccine. In a push towards this elimination goal, Germany introduced a recommendation on MMR vaccination for adults in 2010 to prevent increasing numbers of measles cases among adults and to strengthen herd immunity.

METHODS

The prevalence of anti-measles, -mumps, and -rubella IgG antibodies was analysed in 7,115 participants between the ages of 18 and 79 years in the German Health Interview and Examination Survey. Risk factors of seronegativity of adults born 1970 or later were determined.

FINDINGS

The seroprevalence of anti-measles IgG antibodies was more than 97% in adults born before 1965 and less than 90% in adults born afterwards. Prevalence and GMTs declined with later years of birth. Seronegativity was associated with two-sided migration background and region of residence in East Germany. For anti-mumps IgG antibodies, the seroprevalence was less than 90% in almost all age groups. Prevalence and GMTs declined with later years of birth. Seronegativity was not associated with any socio-demographic factor. Anti-rubella IgG seropositivity was found in more than 90% of adults born before 1985. GMTs declined in younger age groups. Seronegativity was associated with birth between 1980 and 1993 and male gender. High socio-economic status lowered the odds of being seronegative.

INTERPRETATION

These data reinforce the implementation of the vaccination recommendation for adults and provide the basis for further evaluation of this measure.

FUNDING

The Federal Ministry of Health, Germany.

Epidemiology Survey of Measles in Kazakhstan

BACKGROUND: Measles (rubella) is a highly contagious disease that is caused by a virus in the Paramyxoviridae family. The measles virus is directly responsible for more than 100,000 deaths each year. Epidemiological studies have linked measles to increased morbidity and mortality many years after infection, but the reasons underlying this phenomenon are poorly understood. The virus attacks immune cells, causing acute suppression of the immune system. The World Health Organization recommends a two-dose vaccination policy, with the first dose administered during the 1st year of life, and coverage should be maintained in at least 90–95% of the population to halt transmission. In many countries, the measles vaccine is included in the immunization program and is freely available to all. Today, despite active immunization of the population, measles still occurs in the Republic of Kazakhstan. AIM: The objective of our study was to analyze the epidemiological characteristics of measles in the Republic of Kazakhstan during the rise of the disease. METHODS: Statistical data were obtained from the Committee on Public Health Protection on the incidence of measles in The Republic of Kazakhstan for the period from November 1, 2018 to December 30, 2019. STUDY DESIGN: Epidemiology survey. RESULTS: The article contains epidemiological data on the incidence of measles in the regions of the Republic of Kazakhstan among children, age, and gender characteristics. CONCLUSION: In the period from November 2018 to December 2019, there was a tendency to increase the incidence of measles in the republic. In terms of morbidity, Nur-Sultan was the leader, where the number of cases was 22.9% (n = 3181). The largest number of registered cases, 58.2% (n = 5745), occurred in children aged 1–14 years. Measles remains an unresolved global problem and groups of undervaccinated and unvaccinated populations remain vulnerable during epidemics.

Seroprevalence of IgG antibodies against measles in a selected Polish population - do we need to be re-vaccinated?

Introduction

Measles is highly contagious, but preventable viral disease. Its outbreaks appear all over the world, and decreasing herd immunity excludes its elimination. High levels of IgG antibodies against a virus efficiently protects against infection.

Aim of this study

To assess the seroprevalence of anti-measles IgG in the serum of patients at different age levels tested for measles IgG at our laboratory.

Material and methods

The study was conducted from March to June of 2019. Retrospective analysis included results for measles-specific IgG from 364 tested patients. The age of enrolled subjects ranged from four months to 101 years, with a median age of 46, and a mean age of 43 ±18. Quantification of anti-measles IgG was performed using indirect chemiluminescence immunoassays on the DiaSorin Liaison® automated analyzer.

Results

Our results showed a seropositivity ratio of 78.02%. The lowest number of seropositive subjects was in the group of infants (0-1 years old), with a ratio of 53.85%, and the group of adults of 19-38 years old at 55.68%. The group of the oldest patients (70-101 years old) had the highest ratio of seropositive subjects (100%), while adults of 60-69 years old had a seropositivity ratio of 97.22%.

Conclusions

These data suggest that the group of young adults who were vaccinated with one or two doses of MMR vaccine in childhood are the most susceptible for infection, and when working in contact with other people, should be re-vaccinated for protection against measles.

Seroepidemiological study of rubella in Vojvodina, Serbia: 24 years after the introduction of the MMR vaccine in the national immunization programme

Although rubella is usually a mild childhood disease, this infection in early pregnancy poses a serious problem due to its teratogenic effect. The goal of interrupted circulation and elimination of rubella virus was achieved in many countries in the world. The aim of this study was to determine the status of rubella immunity in Vojvodina and evaluate Serbia's progress toward this goal. A total of 3404 residual serum samples from patients of all ages (1 to 84 years) were included in the study. Samples were collected between May 2015 and December 2017 in Vojvodina. Rubella IgG antibodies were determined using an indirect chemiluminescent immunoassay. Percentage of participants seropositive for rubella antibodies was 92.9% in the entire sample. The highest number of seronegatives was in the youngest (1 year) age group (44.7%), followed by the group aged 24-49 (6.4%) and 2-11 years (6.2%). The absence of a higher percentage of children with protective anti-rubella antibodies in the group aged 2-11 can be explained by a lower immunization coverage during certain years. Participants in the group aged 24-49 were born during the pre-vaccination period with lower rubella incidence, leading to the conclusion that not all individuals of that age came into a contact with the virus. Comparing levels of anti-rubella IgG antibodies of seropositive males and females of different ages reveals that the immunity after a contact with the virus and a previously acquired infection is stronger than the immunity after the vaccination. Although the incidence rate of rubella in Vojvodina has been low for the last ten years, there is still a risk of an outbreak due to a decrease in immunization coverage. This study shows that the percentage of susceptible individuals is high, especially considering women aged 24-49, and that additional ("catch-up") immunization is required.

Vaccination coverage and immunity levels against vaccine-preventable diseases in male Air Force recruits in Greece

AIM

Data about susceptibility rates in young adults are scarce. We estimated the complete vaccination rates, timeliness of vaccinations and susceptibility rates among male military recruits in Greece.

METHODS

A standardized form was used to collect data. Immunity against measles, rubella, varicella, hepatitis A and hepatitis B was serologically estimated.

RESULTS

We studied 385 recruits with a mean age of 23.5 years (range: 18.3-29.9 years). Complete vaccination rates were 94.3% for measles, 100% for rubella, 15% for varicella, 73.9% for hepatitis A and 96.5% for hepatitis B. Only 10.8% of participants were fully vaccinated against all five diseases. Timely vaccination was 47.2% for measles, 89.3% for rubella and 48.1% for hepatitis B. Recruits >23 years had a 1.5-fold increased probability for incomplete vaccinations compared to younger recruits. Laboratory-confirmed immunity rates were 80% against measles, 85.7% against rubella, 85.2% against varicella, 69.4% against hepatitis A and 77.1% against hepatitis B. It is estimated that approximately 388,696 persons aged 18-30 years are susceptible to measles, 277,640 persons to rubella, 287,736 persons to varicella, 595,664 persons to hepatitis A and 444,224 persons to hepatitis B in Greece.

CONCLUSION

Our study showed that young adults have significant immunity gaps against measles, rubella, varicella, hepatitis A and hepatitis B. Complete vaccination rates were suboptimal against hepatitis A and varicella. Strategies to access young adults and increase immunity rates through catch-up vaccination services should be investigated. A third dose of MMR vaccine should be considered for young adolescents in Greece.