Large measles outbreak introduced by asylum seekers and spread among the insufficiently vaccinated resident population, Berlin, October 2014 to August 2015

Detection of measles virus in Bulgaria from 2012 to 2018

AIM

To determine the circulation patterns of measles virus in Bulgaria from 2012 to 2018 after a large measles outbreak in the country (2009-2011).

METHODS

Three types of clinical material were collected: serum samples, urine samples, and nasal swabs. Enzyme-linked immunosorbent assay (ELISA) was used to detect specific viral immunoglobulin (Ig) M/IgG antibodies. Viral RNA was extracted from all urine and nasal swabs.

RESULTS

In the investigated period, 102 patients were confirmed to have measles (age range: two months to 55 years). A total of 101 samples (99%) were measles-IgM positive. Most of them were detected in 2017 (73%, 74/101), when a measles outbreak in the country was reported. The majority of patients were unvaccinated children aged under 13 months. Out of 101 measles serum samples confirmed by ELISA, 18 (20.45%) were measles-IgG positive and 15 (17.05%) were borderline. Thirty-three positive PCR products were sequenced and genotyped. In 2013, 2016, 2017, and 2018, three different measles viral genotypes were detected: D8, H1, and B3. Most patients were unvaccinated or insufficiently vaccinated.

CONCLUSION

Preventive measures are indispensable to limit the infection in different regions of Bulgaria and its spread to other countries. As vaccination coverage against measles and other vaccine-preventable infections, including SARS-Co2, is low, it is necessary to perform molecular identification of viruses to monitor their circulation and pathogenicity.

Access to Vaccination among Disadvantaged, Isolated and Difficult-to-Reach Communities in the WHO European Region: A Systematic Review

Vaccination has a significant impact on morbidity and mortality. High vaccination coverage rates are required to achieve herd protection against vaccine-preventable diseases. However, limited vaccine access and hesitancy among specific communities represent significant obstacles to this goal. This review provides an overview of critical factors associated with vaccination among disadvantaged groups in World Health Organisation European countries. Initial searches yielded 18,109 publications from four databases, and 104 studies from 19 out of 53 countries reporting 22 vaccine-preventable diseases were included. Nine groups representing the populations of interest were identified, and most of the studies focused on asylum seekers, refugees, migrants and deprived communities. Recall of previous vaccinations received was poor, and serology was conducted in some cases to confirm protection for those who received prior vaccinations. Vaccination coverage was lower among study populations compared to the general population or national average. Factors that influenced uptake, which presented differently at different population levels, included health service accessibility, language and vaccine literacy, including risk perception, disease severity and vaccination benefits. Strategies that could be implemented in vaccination policy and programs were also identified. Overall, interventions specific to target communities are vital to improving uptake. More innovative strategies need to be deployed to improve vaccination coverage among disadvantaged groups.

Sex and age as determinants of the seroprevalence of anti-measles IgG among European healthcare workers: A systematic review and meta-analysis

INTRODUCTION

The international literature shows good evidence of a significant rate of measles susceptibility among healthcare workers (HCWs). As such, they are an important public health issue.

METHODS

We conducted a systematic review and meta-analysis to estimate the prevalence of susceptible HCWs in EU/EEA countries and in the UK and to explore the characteristics (sex and age differences) and management of those found to be susceptible.

RESULTS

Nineteen studies were included in the meta-analysis. The prevalence of measles-susceptible HCWs was 13.3% (95 %CI: 10.0-17.0%). In a comparison of serosusceptible female vs. male HCWs, the RR was 0.92 (95 %CI = 0.83-1.03), and in a comparison of age classes (born after vs. before 1980) the RR was 2.78 (95 %CI = 2.20-3.50). The most recent studies proposed the mandatory vaccination of HCWs.

DISCUSSION

According to our meta-analysis, the prevalence of serosusceptible European HCWs is 13%; HCWs born in the post-vaccination era seem to be at higher risk. Healthcare professionals susceptible to measles are a serious epidemiological concern. Greater efforts should therefore be made to identify those who have yet to be vaccinated and actively encourage their vaccination.

Evolving measles status and immunization policy development in six European countries

Developing and implementing new immunization policies in response to shifting epidemiology is a critical public health component. We adopted a mixed-methods approach (via narrative literature review [101 articles] and 9 semi-structured interviews) to evaluate policy development in response to shifting measles epidemiology in six European countries (Italy, Belgium, Germany, Romania, UK, and Ukraine); where policies and strategies have evolved in response to country-specific disease and vaccination patterns. Periodic outbreaks have occurred in all countries against a background of declining measles-containing-vaccine (MCV) uptake and increasing public vaccine hesitancy (with substantial regional or social differences in measles burden and vaccine uptake). Health-care worker (HCW) vaccine skepticism is also seen. While many outbreaks arise or involve specific susceptible populations (e.g., minority/migrant communities), the broader pattern is spread to the wider (and generally older) population; often among incompletely/non-vaccinated individuals as a legacy of previous low uptake. Immunization policy and strategic responses are influenced by political and social factors, where public mistrust contributes to vaccine hesitancy. A strong centralized immunization framework (allied with effective regional implementation and coherent political commitment) can effectively increase uptake. Mandatory vaccination has increased childhood MCV uptake in Italy, and similar benefits could be anticipated for other countries considering vaccine mandates. Although possible elsewhere, socio-political considerations render mandating impractical in other countries, where targeted immunization activities to bolster routine uptake are more important. Addressing HCW skepticism, knowledge gaps, improving access and increasing public/community engagement and education to address vaccine hesitancy/mistrust (especially in communities with specific unmet needs) is critical.

Specifically Increased Rate of Infections in Children Post Measles in a High Resource Setting

OBJECTIVES

Post-measles increased susceptibility to subsequent infections seems particularly relevant in low-resource settings. We tested the hypothesis that measles causes a specifically increased rate of infections in children, also in a high-resource setting.

METHODS

We conducted a retrospective cohort study on a large measles outbreak in Berlin, Germany. All children with measles who presented to hospitals in Berlin were included as cases, children with non-infectious and children with non-measles infectious diseases as controls. Repeat visits within 3 years after the outbreak were recorded.

RESULTS

We included 250 cases, 502 non-infectious, and 498 infectious disease controls. The relative risk for cases for the diagnosis of an infectious disease upon a repeat visit was 1.6 (95% CI 1.4-2.0, p < 0.001) vs. non-infectious and 1.3 (95% CI 1.1-1.6, p = 0.002) vs. infectious disease controls. 33 cases (27%), 35 non-infectious (12%) and 57 (18%) infectious disease controls presented more than three times due to an infectious disease (p = 0.01, and p = 0.02, respectively). This results in a relative risk of more than three repeat visits due to an infection for measles cases of 1.8 (95% CI 1.3-2.4, p = 0.01), and 1.4 (95% CI 1.0-1.9, p = 0.04), respectively.

CONCLUSION

Our study demonstrates for the first time in a high-resource setting, that increased post-measles susceptibility to subsequent infections in children is measles-specific-even compared to controls with previous non-measles infections.

[Opinion Survey of Paediatricians on Vaccination Status of Refugee Children - Challenges of a Medical Connection to the Regular Outpatient Care System]

BACKGROUND

In addition to the primary health care of refugees, their integration into the regular outpatient care system should be ensured. Initial data suggest that a gap of vaccination among (school) children of refugee families might have emerged in the period between the first general inspection on arrival (the first central health measure) and the transition to the local health care system.

OBJECTIVES

The aim of this study was to obtain the opinion of practicing paediatricians regarding the vaccination status of refugee children to examine whether a variance in the measles, mumps, rubella (varicella) vaccination schedule might have emerged between the periods of initial admission and school enrolment examination. Evaluations of both inhibiting and promoting conditions should generate fields of action regarding the systematic integration into the regular health care system.

METHOD

Qualitative interviews with experts as well as a quantitative questionnaire survey to measure the opinion of registered paediatricians in Münster were analyzed.

RESULTS

The assessments showed that there was no clear vaccination gap among (school) children of refugee families. One challenge was the systematic integration into the local outpatient care system. Critical issues were inadequate vaccination education, language barriers, and frequent changes in location. The vaccination engagement and vaccination behaviour of refugees were assessed as most positive. International standards, in particular the sphere standards, attracted insufficient attention in practical implementation within the refugee relief programs.

CONCLUSIONS

Based on the results, it is possible to identify fields of action for the prevention of vaccination gaps among refugees as well as for their systematic integration into the regular outpatient care system. The sphere standards as international standards should be incorporated more consciously.

Migration and outbreaks of vaccine-preventable disease in Europe: a systematic review

Migrant populations are one of several underimmunised groups in the EU or European Economic Area (EU/EEA), yet little is known about their involvement in outbreaks of vaccine-preventable diseases. This information is vital to develop targeted strategies to improve the health of diverse migrant communities. We did a systematic review (PROSPERO CRD42019157473; Jan 1, 2000, to May 22, 2020) adhering to PRISMA guidelines, to identify studies on vaccine-preventable disease outbreaks (measles, mumps, rubella, diphtheria, pertussis, polio, hepatitis A, varicella, Neisseria meningitidis, and Haemophilus influenzae) involving migrants residing in the EU/EEA and Switzerland. We identified 45 studies, reporting on 47 distinct vaccine-preventable disease outbreaks across 13 countries. Most reported outbreaks involving migrants were of measles (n=24; 6496 cases), followed by varicella (n=11; 505 cases), hepatitis A (n=7; 1356 cases), rubella (n=3; 487 cases), and mumps (n=2; 293 cases). 19 (40%) outbreaks, predominantly varicella and measles, were reported in temporary refugee camps or shelters. Of 11 varicella outbreaks, nine (82%) were associated with adult migrants. Half of measles outbreaks (n=11) were associated with migrants from eastern European countries. In conclusion, migrants are involved in vaccine-preventable disease outbreaks in Europe, with adult and child refugees residing in shelters or temporary camps at particular risk, alongside specific nationality groups. Vulnerability varies by disease, setting, and demographics, highlighting the importance of tailoring catch-up vaccination interventions to specific groups in order to meet regional and global vaccination targets as recommended by the new Immunisation Agenda 2030 framework for action. A better understanding of vaccine access and intent in migrant groups and a greater focus on co-designing interventions is urgently needed, with direct implications for COVID-19 vaccine delivery.

Ten years of weekly epidemiological teleconference (EpiLag) - an effective and time-efficient tool for infectious disease event information, Germany, 2009-2018

In 2009, the Robert Koch Institute (RKI) and the 16 German federal state public health authorities (PHAs) established a weekly epidemiological teleconference (EpiLag) to discuss infectious disease (ID) events and foster horizontal and vertical information exchange. We present the procedure, discussed ID topics and evaluation results of EpiLag after 10 years. We analysed attendance, duration of EpiLag and the frequency of reported events. Participants (RKI and state PHA) were surveyed regarding their satisfaction with logistics, contents and usefulness of EpiLag (Likert scales). Between 2009 and 2018, RKI hosted 484 EpiLag conferences with a mean duration of 25 min (range: 4–60) and high participation (range: 9–16; mean: 15 PHAs). Overall, 2975 ID events (39% international, 9% national and 52% subnational) were presented (mean: 6.1 per EpiLag), most frequently on measles (18%), salmonellosis (8%) and influenza (5%). All responding participants (14/16 PHAs and 9/9 at RKI) were satisfied with the EpiLag's organization and minutes and deemed EpiLag useful for an overview and information distribution on ID events relevant to Germany. EpiLag is time efficient, easily applicable and useful for a low-threshold event communication. It supports PHAs in crises and strengthens the network of surveillance stakeholders. We recommend its implementation to other countries or sectors.

Factors associated with knowledges and attitudes about measles and rubella immunization in a non-health care occupational setting in Japan

INTRODUCTION

Elimination of measles and rubella has been achieved in several countries and some regions. After verified measles elimination, some countries have reported outbreaks among adults in occupational settings such as health care institution and school setting. Studies have reported that knowledge and attitude for measles and/or rubella are significantly associated with immunization uptake in adults, but few studies have been conducted in settings other than health care facilities and schools.

METHODS

We conducted a cross-sectional study among 134 office employees during a routine health checkup in June 17-20, 2014, to examine the association between willingness to receive immunization and knowledge and attitudes.

RESULTS

Approximately 75% had a protective level of antibody for measles (PA≥1:256) and rubella (HI ≥ 32 IU/mL). After adjustment for sex, age and immune status, the attitudes that immunization prevents measles (adjusted odds ratio [aOR] = 7.8, 95% confidence interval [95%CI]: 2.5-24.7) and prevents infection and transmission to others (aOR = 4.0, 95%CI: 1.4-11.4). Knowing that males are the vulnerable group for rubella infection (aOR = 5.8, 95%CI: 2.4-13.9), attitude that immunization prevents rubella infection (aOR = 7.9, 95%CI: 2.4-26.5), and prevents infection and transmit to others (aOR = 6.7, 95%CI: 2.2-20.1) were significantly associated with willingness to receive immunization after adjustment for sex, age, and immune status.

CONCLUSIONS

Studies have shown that physicians and other health care workers are important source of information for promotion of immunization. Thus, we recommend that physicians educate and promote immunization for measles and/or rubella to adults working in offices during routine health checks.

Utility of the Tétanos Quick Stick® in the vaccine catch-up of adult migrants without proof of prior vaccination

BACKGROUND

Unknowing immunity status make migrants vaccine catch-up difficult. The interest of using a rapid tetanus immunotest as the Tétanos Quick Stick® (TQS®) to assess immunity status against tetanus has been evaluated in emergency rooms and it is now commonly used. The study aim was to evaluate TQS® as a tool for migrants' vaccine catch-up.

METHODS

From December 2018 to February 2019, a prospective study was performed and included consecutively migrants who attented to the primary medicine outconsultation of a health care centre in Paris. Migrants above 18, without any records of tetanus immunization were included and a TQS® was performed during a medical consultation. Adapted vaccine catch-up was then proposed. Immunity against tetanus among migrants, factors associated with positive TQS® and costs savings were evaluated.

RESULTS

TQS® test was positive for 32% of the 310 included patients. In the univariable analysis, factors associated to the presence of a positive TQS® test were a female gender (OR = 1.69 CI95% [1.02-2.80]) and an urban living in the country of origin (OR = 1.79 CI95% [1.07-3.02]). In the multivariable analysis, these factors were not significantly associated to a positive TQS®. Anamnesis was not correlated to the immunity status: only 26% of the migrants who reported vaccinations in childhood, adolescence and adulthood had a positive TQS® test. The use of TQS® test allowed savings of 6,522 US$ as compared to the immediate catch-up strategy for the 310 patients.

CONCLUSION

The TQS® test is an acceptable, simple, rapid and cost saving test that could find a place in the migrants' vaccine catch-up.

Investigation of Measles Outbreak among Thai and Migrant Workers in Two Factories in Nakhon Pathom, Thailand, 2019

On 22 March 2019 the Thai Department of Disease Control (DDC) was notified that 16 workers, including Thai and Myanmar migrant workers, from two factories located in Nakhon Phathom Province, had presented with a fever with rash during the previous 2 weeks. Active case finding was conducted among workers in both factories using face-to-face interviews. Suspected cases were defined as a worker who developed fever with rash with one of the following symptoms: cough, coryza or conjunctivitis. Testing for measles IgM antibodies and viral identification through throat swabs by polymerase chain reaction (PCR) were performed to confirm diagnosis. Vaccination history among cases was reviewed. Nationality and age-specific attack rates (AR) were calculated. An environmental study and a social network analysis were conducted to better understand the transmission process. A total 56 cases (AR = 0.97%) were identified. Of 21 serum measles IgM collected, 8 (38.0%) were positive. Of 8 throat swabs collected, 5 (62.5%) were positive for measles genotype D8. The disease attack rate in migrant employees was twice as large as the rate in Thai counterparts (AR = 0.7 and 1.4%). The first case was identified as a Myanmar worker who arrived in Thailand two weeks prior to his illness. The Myanmar workers’ accommodation was more crowded than that for Thai workers. The hot spots of transmission were found at a drinking water tank which had shared glasses. Among the cases, 62.5% could not recall their vaccination history, and 25% had never had an injection containing a measles vaccination. The majority of migrant cases had never completed a two-dose measles vaccination. To halt the outbreak, measles vaccines were administered to the employees, particularly those working in the same sections with the cases and shared glasses were removed. For future policy action, a vaccination program should be incorporated into the work permit issuance process.

Epidemiological, clinical and laboratory characteristics of the measles resurgence in the Republic of Serbia in 2014-2015

The Republic of Serbia is a country with ongoing endemic transmission of measles. The aim of this study is to summarize the main characteristics of the measles resurgence that occurred in Serbia in 2014-2015. The national surveillance data on measles was analysed in relation to the clinical, epidemiological and laboratory data. Between November 2014 and December 2015 a measles resurgence with 420 cases was observed in Serbia. Measles virus was initially introduced by and spread among citizens of Bosnia and Herzegovina with temporary residence in Serbia, before spreading to the resident population. Of the 223 patients with available medical records, 173 (77.6%) were unvaccinated. The overall measles incidence during the outbreak was 5.8/100.000. The highest age-specific incidence rate was recorded in children aged ≤4 years (25.9/100.000), but most cases (67.9%) were ≥20 years old. Hospitalization rate was high (32.9%) and included two cases of encephalitis associated with measles. In total, 42 health-care workers and 22 related cases including hospitalized patients (n = 13) contracted measles. The overall percentage of laboratory confirmed cases was 81.7% (n = 343/420). All measles virus sequences except one (D9) belonged to genotype D8, suggesting interruption of transmission after the previous outbreak in 2010-2011 caused by genotype D4 viruses. The growing number of adult patients as compared to previous epidemics, suggests an urgent need for supplementary immunization activities targeting susceptible health care workers, unvaccinated or incompletely vaccinated adults as well as people without vaccination records. The comprehensive investigation of the 2014/2015 measles resurgence will contribute to decisions about appropriate countermeasures to stop the future measles resurgences in Serbia.

Immunization coverage among refugee children in Berlin

Background

The Tempelhof refugee camp offers in-camp immunizations. Other camps, like Neukölln, rely on a centralized immunization system. We aimed to determine the impact of conflict on immunization rates of Syrian children and to measure the efficacy of in-camp immunization services.

Methods

Families with children aged 1-5 in Tempelhof and Neukölln camps were surveyed. Surveys included siblings under the age of 18. Differences were compared using χ² test.

Results

Data on 179 children at Tempelhof and 40 children at Neukölln were collected. At Tempelhof, amongst Syrian children, 27.8% under the age of 5 were “fully immunized-memory,” in contrast to 73.7% over the age of 5 (P = 0.005). This difference in immunization rates by memory between the age groups was not observed in Afghani children (P = 0.34) or in Iraqi children (P = 0.10). Furthermore, compared to the 27.8% of Syrian children, 75% of Afghani children under the age of 5 were “fully vaccinated-memory” (P = 0.0009). Compared to Tempelhof, more children at Neukölln were partially immunized (93%) or had no immunizations (5%) (P < 0.001).

Estimating age-specific vaccine effectiveness using data from a large measles outbreak in Berlin, Germany, 2014/15: evidence for waning immunity

BackgroundMeasles elimination is based on 95% coverage with two doses of a measles-containing vaccine (MCV2), high vaccine effectiveness (VE) and life-long vaccine-induced immunity. Longitudinal analysis of antibody titres suggests existence of waning immunity, but the relevance at the population-level is unknown.AimWe sought to assess presence of waning immunity by estimating MCV2 VE in different age groups (2-5, 6-15, 16-23, 24-30 and 31-42 years) in Berlin.MethodsWe conducted a systematic literature review on vaccination coverage and applied the screening-method using data from a large measles outbreak (2014/15) in Berlin. Uncertainty in input variables was incorporated by Monte Carlo simulation. In a scenario analysis, we estimated the proportion vaccinated with MCV2 in those 31-42 years using VE of the youngest age group, where natural immunity was deemed negligible.ResultsOf 773 measles cases (median age: 20 years), 40 had received MCV2. Average vaccine coverage per age group varied (32%-88%). Estimated median VE was  > 99% (95% credible interval (CrI): 98.6-100) in the three youngest age groups, but lower (90.9%, 95% CrI: 74.1-97.6) in the oldest age group. In the scenario analysis, the estimated proportion vaccinated was 98.8% (95% CrI: 96.5-99.8).ConclusionVE for MCV2 was generally high, but lower in those aged 31-42 years old. The estimated proportion with MCV2 should have led to sufficient herd immunity in those aged 31-42 years old. Thus, lower VE cannot be fully explained by natural immunity, suggesting presence of waning immunity.

Measles and rubella seroimmunity in newly arrived adult immigrants in Sweden

BACKGROUND

International migrants could be considered as a risk group for being susceptible to vaccine preventable diseases such as measles and rubella. However, data on immunity in different migrant groups are scarce. Apart from asylum seekers and refugees, other immigrant groups might also be at risk. We have examined measles and rubella specific IgG antibodies among newly arrived adult immigrants in Skåne region in southern Sweden. In contrast to children, adult immigrants are not offered catch-up vaccinations after arrival.

METHODS

Stored serum samples from 989 asylum seekers and 984 pregnant women from the antenatal screening program, who had recently settled in Sweden, were analyzed for specific measles and rubella IgG-antibodies. Sex, age, reason for screening and geographic origin were variables entered into a multivariate regression model.

RESULTS

There were considerable differences in seroimmunity to measles with regard to geographic origin (44-97%). Measles seroimmunity gaps were most prominent in immigrants from some European regions such as the Baltic countries, the former Yugoslavia and the Newly Independent States and Russia. Seroprotection for rubella varied less between geographic regions (90-99%).

CONCLUSION

Susceptibility to measles among adult immigrants arriving in Sweden varies considerably depending on their geographic origin. Vaccinations against measles and rubella should be offered to groups of immigrants who might be incompletely immunized.

Interventions to Improve Vaccination Uptake and Cost Effectiveness of Vaccination Strategies in Newly Arrived Migrants in the EU/EEA: A Systematic Review

Newly arrived migrants to the EU/EEA (arrival within the past five years), as well as other migrant groups in the region, might be under-immunised and lack documentation of previous vaccinations, putting them at increased risk of vaccine-preventable diseases circulating in Europe. We therefore performed a systematic review conforming to PRISMA guidelines (PROSPERO CRD42016045798) to explore: (i) interventions that improve vaccine uptake among migrants; and (ii) cost-effectiveness of vaccination strategies among this population. We searched MEDLINE, Embase, CINAHL, and Cochrane Database of Systematic Reviews (CDSR) between 1 January 2006 to 18 June 2018. We included three primary intervention studies performed in the EU/EEA or high-income countries and one cost effectiveness study relevant to vaccinations in migrants. Intervention studies showed small but promising impact only on vaccine uptake with social mobilization/community outreach, planned vaccination programs and education campaigns. Targeting migrants for catch-up vaccination is cost effective for presumptive vaccination for diphtheria, tetanus, and polio, and there was no evidence of benefit of carrying out pre-vaccination serological testing. The cost-effectiveness is sensitive to the seroprevalence and adherence to vaccinations of the migrant. We conclude that scarce but direct EU/EEA data suggest social mobilization, vaccine programs, and education campaigns are promising strategies for migrants, but more research is needed. Research should also study cost effectiveness of strategies. Vaccination of migrants should continue to be a public heath priority in EU/EEA.

Notifiable infectious diseases in refugees and asylum seekers: experience from a major reception center in Munich, Germany

PURPOSE

In 2016, the number of refugees worldwide reached 65.6 million. So far, only limited data are available on the health status of refugees and asylum seekers (RAs). Especially, notifiable infectious diseases (NIDs) carry the risk of outbreaks in communal accommodations hosting RAs.

METHODS

We conducted a monocentric retrolective cross-sectional study including 15,137 RAs treated in a special health care unit for RAs located in the major reception center in Munich from November 2014 to October 2016. Altogether 811 RAs with NIDs according to sections 6 and 7 of the German Infection Protection Act or with other infections relevant in the setting of a communal accommodation (RIDs) could be identified.

RESULTS

The gender and age distribution was generally comparable to that of refugees in Germany. However, patients from East Africa and Nigeria were significantly overrepresented. NIDs/RIDs were dominated by cases of tuberculosis, hepatitis B, and vaccine-preventable and parasitic diseases. Significant risk factors included country of origin (COI) and age for hepatitis B, age for hepatitis C, gender and age for HIV, and COI, gender and age for tuberculosis and ectoparasitosis. Calculated prevalences of hepatitis B, hepatitis C, and HIV were mostly below those of the COI. Incidences of tuberculosis were mostly strongly elevated.

CONCLUSIONS

COI, gender, and age have an impact on the occurrence of NIDs/RIDs. Early vaccinations and improved hygiene could be effective in preventing NIDs/RIDs in communal accommodations. Screening, prompt therapy, and infection protection measures are necessary to prevent the transmission of diseases.

Molecular surveillance of measles and rubella in the WHO European Region: new challenges in the elimination phase

BACKGROUND

The WHO European Region (EUR) has adopted the goal of eliminating measles and rubella but individual countries perform differently in achieving this goal. Measles virus spread across the EUR by mobile groups has recently led to large outbreaks in the insufficiently vaccinated resident population. As an instrument for monitoring the elimination process and verifying the interruption of endemic virus transmission, molecular surveillance has to provide valid and representative data. Irrespective of the country's specific situation, it is required to ensure the functionality of the laboratory surveillance that is supported by the WHO Global Measles and Rubella Laboratory Network.

AIMS

To investigate whether the molecular surveillance in the EUR is adequate for the challenges in the elimination phase, we addressed the quality assurance of molecular data, the continuity and intensity of molecular monitoring, and the analysis of transmission chains.

SOURCES

Published articles, the molecular External Quality Assessment Programme of the WHO, the Centralized Information System for Infectious Diseases of the WHO EUR and the WHO Measles and Rubella Nucleotide Surveillance databases served as information sources.

CONTENT

Molecular proficiency testing conducted by the WHO in 2016 has shown that the expertise for measles and rubella virus genotyping exists in all parts of the EUR. The analysis of surveillance data reported nationally to the WHO in 2013-2016 has revealed some countries with outbreaks but not sufficiently representative molecular data. Long-lasting supranational MV transmission chains were identified.

IMPLICATIONS

A more systematic molecular monitoring and recording of the transmission pattern for the whole EUR could help to create a meaningful picture of the elimination process.