Laboratory diagnosis of measles infection using molecular and serology during 2019-2020 outbreak in Brazil

INTRODUCTION

Laboratory diagnosis of measles can be challenging, and the reintroduction of the measles virus in Brazil has brought about new issues. The aim of this study was to analyze the qPCR results of swab and urine samples and compare them with those of immunological methods for the diagnosis of measles.

METHODS

This was a cross-sectional study based on a retrospective analysis of 3,451 suspected cases using laboratory test surveillance databases for qPCR (respiratory swabs and urine) and serologic tests for IgM and paired IgG. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and agreement through kappa and adjusted kappa coefficients (PABAK) were calculated using different diagnostic strategies.

RESULTS

The swab and urine samples obtained using real-time qPCR were equivalent. Samples collected simultaneously and the combined samples showed moderate agreement between IgM ELISA and real-time qPCR; however, 48.9 % of the IgM ELISA analyses did not demonstrate detectable qPCR concentrations during simultaneous collections and 43.9 % of combined collections. The paired analysis of IgG showed an accuracy of 67.5 % for IgM and 90.7 % for real-time qPCR.

CONCLUSIONS

Diagnosis based on IgM presents detection delimitation in samples collected early (1-5 days), suggesting that these individuals satisfy at least two criteria. In addition to qPCR, paired analysis of IgG using ELISA can be used to increase the sensitivity and specificity of laboratory diagnoses.

Measles, mumps, rubella and varicella antibodies among international and domestic university students

BACKGROUND

Vaccine-preventable infections are generally well controlled in Australia. However, gaps in immunity can lead to outbreaks and are important to identify. Young adults are a highly mobile population and a potential source of imported infections. We aimed to evaluate anti- measles, mumps, rubella and varicella (MMR&V) IgG seroprevalence and explore factors relating to antibody seropositivity.

METHODS

A cross-sectional online survey was conducted among students from a large Australian university to collect demographic, vaccination, infection and travel characteristics. Blood samples were collected to measure MMR&V seroprevalence. Logistic regression was used to identify factors associated with seropositivity.

RESULTS

Among 804 university students, seroprevalence (positive or equivocal) for measles was 82.3% (95% CI 79.6-84.8%), mumps 79.5% (95% CI 76.7-82.3%), rubella 91.5% (95% CI 89.6-93.5%) and varicella 86.2% (95% CI 84.1-88.8%), with 452 (56.2%, 95% CI 52.8-59.6) seropositive to all four viruses. Varicella seropositivity was highest in the older birth cohort (born 1988-1991). Measles seropositivity was higher for international students compared to domestic students. Among international students, mumps seroprevalence was significantly lower than measles and rubella seroprevalence. International travel in the previous 12 months was reported by 63.1% of students, but only 18.2% of travellers reported seeking pre-travel health advice prior to most recent international travel.

CONCLUSIONS

Overall, this study suggests immunity to MMR&V is sub-optimal. We found the university student population to be highly mobile and unlikely to seek pre-travel advice; thus, they are a potential source of infection importation. The implementation of university immunization policies could address the gaps identified and our findings can inform the development of targeted vaccination campaigns.

Achieving measles elimination and emerging modified measles: Longitudinal measles epidemiology from 1982 to 2021 in Osaka Prefecture, Japan

BACKGROUND

Measles is a contagious viral disease causing infant mortality in developing countries without vaccination programs. In Japan, measles vaccination was launched in 1978, surveillance commenced in 1981, and elimination was achieved in 2015. This was due to improved, legally required surveillance methods and vaccine programs.

METHODS

The data sets of sentinel (1982-2007) and notifiable (2008-2021) disease surveillance, as well as the vaccination coverage, detected genotypes, and seroepidemiology during the study period in Osaka Prefecture, were analyzed. Additionally, the trend under the current notifiable surveillance was compared before (2008-2014) and after (2015-2021) measles elimination.

RESULTS

Under sentinel surveillance, 51,107 cases were reported, predominantly infants aged 1-4 years (63.6 %). Under notifiable disease surveillance, the 781 patients were predominantly in their 20s-30s (43.7 %). From 2000, the age of the major susceptible group increased due to the rise in vaccination coverage, which exceeded 95% for the first dose in 1998 and 90% for the second dose in 2009. Consistent with these data, seroprevalence exceeded 95% in 2011. However, the geometric mean of the antibody titer showed a decreasing trend with a falling number of patients. Compared with before and after measles elimination, the number of modified measles cases increased from 10.1% to 48.2%. During the study period, 398 strains comprising eight genotypes were identified, and the dominant type changed over time. After measles elimination, genotypes B3 and D8, derived from imported cases, became predominant.

CONCLUSIONS

Improved vaccination coverage and surveillance reduced measles cases and increased herd immunity. However, the lack of a booster effect due to the low incidence of measles caused waning antibody titers despite high seroprevalence, which may contribute to the rising rate of vaccine failures causing modified measles. Careful monitoring of measles incidence and herd immunity are necessary for measles eradication.

Dimeric immunoglobulin A as a novel diagnostic marker of measles infection

IMPORTANCE

The world is facing a measles resurgence, and improved diagnostic tests for measles infection are an urgent World Health Organization research priority. Detection of measles-specific immunoglobulin M (IgM) as a standard diagnostic test has low positive predictive value in elimination settings, and there is a need for new biomarkers of measles infection to enable enhanced surveillance and response to outbreaks. We demonstrate the detection of measles-specific dimeric immunoglobulin A (dIgA) in patients with confirmed measles infections using a new indirect enzyme-linked immunosorbent assay protocol that selects for the dIgA fraction from total IgA in the blood. The magnitude of measles-specific dIgA responses showed a low correlation with IgM responses, and our results highlight the potential of dIgA for further development as an alternative and/or complementary biomarker to IgM for serological diagnosis of measles infection.

Measles seroprevalence in adolescents and young adults living with HIV and response to MMR booster in seronegative ones

OBJECTIVE

The study analyzed people with HIV (PWH) measles seroprevalence and response to MMR booster given to seronegative individuals.

DESIGN

A prospective cohort study with four groups: vertically (v-HIV), horizontally infected (h-HIV) individuals, and two control groups. An MMR booster was offered to seronegative individuals.

RESULTS

Measles seropositivity and IgG antibodies were significantly lower in v-HIV than in the other groups. All measles seronegative patients responded to booster.

CONCLUSION

An MMR booster must be sought during adolescence in vertically PWH.

Health status, healthcare use and child MMR vaccination coverage in Travellers according to their environmental and living conditions in Nouvelle-Aquitaine, France, 2019-2022

BACKGROUND

The poor health status of underserved populations is compounded by low vaccination uptake, leading to a greater risk of epidemics. On October 2017, a measles outbreak started in the southwest of France among under-vaccinated social groups, including Travellers. We aimed to describe the health status, healthcare use and child measles-mumps-rubella (MMR) vaccination coverage in Travellers according to their environmental and living conditions.

METHODS

A cross-sectional study with a three-stage random sample design was conducted between October 2019 and March 2022 in the Nouvelle-Aquitaine region in France. Trained social workers administered face-to-face questionnaires to collect data on adults and children. Anthropometric measurements, vaccination records and data using an environmental exposure questionnaire were also collected.

RESULTS

The participation rate was high (73.6%), with 1030 adults and 337 children included. Concerning the adults, 36.6% had obesity, 14.4% reported diabetes, 24.7% hypertension and 14.4% major depression. The prevalence of major depression was significantly higher in adults living in precarious and unauthorized housing than in those with adequate housing (19.8 vs. 14.7%, P = 0.03). With regard to children, 45.3% had full (i.e. 2-dose) MMR vaccination coverage at 24 months and 17.9% had obesity. Finally, 74.5% of the households experienced housing insecurity, and 22.2% did not have a supply of drinking water.

CONCLUSION

Traveller children and adults faced deleterious environmental and living conditions potentially affecting their health, healthcare use and vaccination coverage. These results demonstrate the need for urgent interventions for underserved populations which take into account their specific needs.

Estimated number of reported vaccine-preventable disease cases averted following the introduction of routine vaccination programs in Sweden, 1910-2019

BACKGROUND

Routine childhood vaccination programs have had enormous positive public health impacts worldwide. However, in some areas, these benefits may be impeded by vaccine hesitancy and undervaccination. We estimated the number of reported cases of measles, pertussis, mumps and poliomyelitis averted in Sweden after the introduction of routine childhood vaccination programs.

METHODS

We used annual national data on population size and the number of reported cases of measles (1911-2019), pertussis (1911-2019), mumps (1914-2019) and poliomyelitis (1910-2019) for Sweden. For each disease, we calculated the median and 95% confidence interval of the annual pre-vaccination incidence to estimate the number of counterfactual cases; that is, the estimated number of cases that would have been observed in the post-vaccination period had no vaccine been introduced (median incidence × average annual population). For the post-vaccination periods, we calculated reported cases averted and assumed all decreases were due to vaccines.

RESULTS

In total, for all four diseases combined, over 2.1 million cases were reported over the respective surveillance periods. Since the introduction of vaccinations, we estimate that over 1.5 million reported cases of these four diseases combined have been averted: measles (633 091), pertussis (608 670), mumps (262 951) and poliomyelitis (58 240). However, due to underreporting, especially during pre-vaccination years, these are likely underestimates.

CONCLUSIONS

Since the introduction of these routine childhood vaccination programs in Sweden, a substantial number of reported cases of vaccine-preventable diseases have been averted. Vigilance against both failure to vaccinate and undervaccination is necessary to prevent future increases of these vaccine-preventable diseases.

The path to eradication of rubella

Since 1969, rubella and its harmful effect on fetuses infected in utero can be prevented by rubella vaccine, usually given in combination with measles vaccine. The rubella vaccine is highly protective both in children and in adults including women intending to become pregnant. Owing to the use of combined measles and rubella vaccines, congenital rubella infection has been eliminated from the Western Hemisphere and nearly all of Europe. Such combined vaccination is now being applied throughout the world, posing the possibility of eventual rubella eradication. The existence of viruses of animals related to rubella does not appear to be a barrier to eradication of the human virus. However, persistent rubella virus in infants infected in utero and of immunosuppressed patients with granulomas may pose a problem for eradication. Nevertheless, this review posits that eradication of rubella is now feasible if routine vaccination of infants and surveillance for chronic infection are correctly applied.

Seroprevalence of Measles in Pairs of Mothers and Newborns in Southern Greece

Maternal immunoglobulin G (IgG) antibodies that are passively transferred to newborns through the placenta confer protection if they are exposed to measles virus. A measles outbreak occurred in several European countries including Greece, between 2016 and 2018. A prospective study was conducted in the General Hospital of Lakonia, regarding the measles seropositivity status of mother and newborn pairs. IgG antibody titer for measles was measured in serum samples acquired from pairs of mothers and newborns. The samples were analyzed through quantitative enzyme-linked immunosorbent assay, and antimeasles IgG >200 IU/mL was considered to be protective. Demographic data for mothers and neonates and data regarding immunization status of mothers were analyzed. Study population included 206 mothers and their newborns. In total, 12.6% of mothers (n = 26) and 10.7% of newborns (n = 22) did not have protective serology. A statistically significant positive linear association between maternal and neonatal antibodies was found (rho = 0.924) (p = 0.001). Neonates whose mothers were seropositive had higher antibodies [geometric mean concentration (GMC): 804.8 (728.3-889.2)] than neonates whose mothers were seronegative/borderline [GMC: 97.7 (64.2-148.8)] (p = 0.001). In the study area, a significant rate of mothers and newborns was found to have nonprotective measles serology that exceeds the limit required for herd immunity. Vaccination coverage in women of reproductive age should be increased to reduce potential for future measles epidemics.

Direct and crowding-out effects of a Hepatitis B vaccination campaign

We evaluate the direct and spillover causal effects of a Hepatitis B (HB) vaccination campaign in French schools on the vaccination adherence of the targeted pupils. Using a regression discontinuity design, we show that this campaign created an exogenous shock on vaccination behavior, increasing the HB vaccination rate for children aged 11 and above. At the same time, we show a drop in the measles, mumps, and rubella (MMR) vaccination rate of the targeted pupils and an increase in the parental belief that measles is a benign disease. We interpret these results as a salience effect: the focus on HB vaccination leads to a decrease in the belief that other vaccines are as important. The effect on MMR vaccination was relatively unexpected and may imply a negative externality. Measles is an extremely contagious disease. If the vaccination rate falls, the disease will spread further, raising the question of the net effect of the HB vaccination campaign on the well-being of the population.

A zero-inflated endemic-epidemic model with an application to measles time series in Germany

Count data with an excess of zeros are often encountered when modeling infectious disease occurrence. The degree of zero inflation can vary over time due to nonepidemic periods as well as by age group or region. A well-established approach to analyze multivariate incidence time series is the endemic-epidemic modeling framework, also known as the HHH approach. However, it assumes Poisson or negative binomial distributions and is thus not tailored to surveillance data with excess zeros. Here, we propose a multivariate zero-inflated endemic-epidemic model with random effects that extends HHH. Parameters of both the zero-inflation probability and the HHH part of this mixture model can be estimated jointly and efficiently via (penalized) maximum likelihood inference using analytical derivatives. We found proper convergence and good coverage of confidence intervals in simulation studies. An application to measles counts in the 16 German states, 2005-2018, showed that zero inflation is more pronounced in the Eastern states characterized by a higher vaccination coverage. Probabilistic forecasts of measles cases improved when accounting for zero inflation. We anticipate zero-inflated HHH models to be a useful extension also for other applications and provide an implementation in an R package.

Measles in vulnerable populations: An outbreak in Roma settlements of Loire-Atlantique, France, 2019

In May 2019, a measles outbreak occurred in the French subregion of Loire-Atlantique, particularly affecting Roma settlements. Various obstacles hindered the implementation of postexposure measures among Roma population, resulting in the spread of the cases to other settlements. Suspected cases of measles were immediately investigated and concerned settlements were visited for measles-mumps-rubella (MMR) vaccination. From July 1 to September 3, 2019, a first and then a second Health Reserve team helped for vaccination on the affected and then also the measles-free settlements. Vaccination uptake was monitored with the use of the department's vaccination center immunization registry. Genotyping of selected samples was performed for comparison with viruses circulating at the same time in France and Romania. As of September 16 2019, 109 cases of measles were confirmed among Roma population, including 99 (91%) children under 15 years. Of the 85 people eligible for vaccination, 60 (71%) had not been vaccinated and 23 (27%) had an unknown vaccination status. Sequence comparison revealed that 28/29 sequenced D8 strains were 100% identical to the strain responsible for a large number of cases throughout France in 2019, and to two sequences reported in Romania among sporadic cases. The vaccination campaign resulted in 1136 people on 35 settlements receiving at least one dose of MMR vaccine and in the increase of one-dose MMR vaccine coverage at 24 months from 43% (23/53) to 91% (48/53). With measles transmission continuing in Europe, efforts must be made to meet immunization coverage targets, particularly in hard-to-reach communities where outbreaks may be difficult to control.

Evaluating effective measles vaccine coverage in the Malaysian population accounting for between-dose correlation and vaccine efficacy

BACKGROUND

Malaysia introduced the two dose measles-mumps-rubella (MMR) vaccine in 2004 as part of its measles elimination strategy. However, despite high historical coverage of MCV1 and MCV2, Malaysia continues to report high measles incidence. This study suggests a novel indicator for investigating population immunity against measles in the Malaysian population.

METHODS

We define effective vaccine coverage (EVC) of measles as the proportion of a population vaccinated with measles-containing vaccine (MCV) and effectively protected against measles infection. A quantitative evaluation of EVC throughout the life course of Malaysian birth cohorts was conducted accounting for both vaccine efficacy (VE) and between-dose correlation (BdC). Measles vaccination coverage was sourced from WHO-UNICEF estimates of Malaysia's routine immunisation coverage and supplementary immunisation activities (SIAs). United Nations World population estimates and projections (UNWPP) provided birth cohort sizes stratified by age and year. A step wise joint Bernoulli distribution was used to proportionate the Malaysian population born between 1982, the first year of Malaysia's measles vaccination programme, and 2021, into individuals who received zero dose, one dose and multiple doses of MCV. VE estimates by age and doses received are then adopted to derive EVC. A sensitivity analysis was conducted using 1000 random combinations of BdC and VE parameters.

RESULTS

This study suggests that no birth cohort in the Malaysian population has achieved > 95% population immunity (EVC) conferred through measles vaccination since the measles immunisation programme began in Malaysia.

CONCLUSION

The persistence of measles in Malaysia is due to pockets of insufficient vaccination coverage against measles in the population. Monitoring BdC through immunisation surveillance systems may allow for the identification of susceptible subpopulations (primarily zero-dose MCV individuals) and increase the coverage of individuals who are vaccinated with multiple doses of MCV. This study provides a tool for assessment of national-level population immunity of measles conferred through vaccination and does not consider subnational heterogeneity or vaccine waning. This tool can be readily applied to other regions and vaccine-preventable diseases.

Measles epidemiological surveillance system before and during the COVID-19 pandemic in Pernambuco, Brazil, 2018-2022: a descriptive evaluation

OBJECTIVE

To evaluate the measles epidemiological surveillance system, before and during the COVID-19 pandemic in Pernambuco, Brazil.

METHODS

This was a descriptive evaluation of the quality (duplicity; completeness; consistency), timeliness and usefulness attributed, classified as excellent ≥ 90.0%, regular ≥ 70.0% and < 90.0%, and poor (< 70.0%). Data from the Notifiable Health Conditions Information System and Laboratory Environment Management System were used, before (03/11/2018-03/10/2020) and during (03/11/2020-03/10/2022) the pandemic.

RESULTS

1,548 suspected measles cases were registered (1,469 before and 79 during the pandemic). In the two periods studied, there were 11 and 1 duplicate records, average completeness in filling out the variables was 99.2% and 95.7%, while average consistency was 96.7% and 97.5%, respectively. Timeliness (receipt of samples, 16.2% and 33.0%. Release of results, 1.3% and 1.3%) and usefulness (43.5% and 24.4%) were poor.

CONCLUSION

Quality was classified as excellent in the periods studied, timeliness and usefulness were classified as poor, signaling non-compliance with the purpose of the system.

MAIN RESULTS

The quality of data from the measles epidemiological surveillance system in Pernambuco was excellent, while its timeliness and usefulness were poor during both periods.

IMPLICATIONS FOR SERVICES

The limited timeliness and, therefore, the low usefulness of the measles epidemiological surveillance system must be discussed in the three government spheres of health service management, with the aim of training the professionals involved, as well as monitoring and evaluating the system.

PERSPECTIVES

Systematic monitoring and evaluation generates evidence that supports health service managers and workers in the timely identification of gaps that compromise the full fulfillment of the objectives proposed.

Progress Toward Measles Elimination - Worldwide, 2000-2022

Measles is a highly contagious, vaccine-preventable disease that requires high population immunity for transmission to be interrupted. All six World Health Organization regions have committed to eliminating measles; however, no region has achieved and sustained measles elimination. This report describes measles elimination progress during 2000-2022. During 2000-2019, estimated coverage worldwide with the first dose of measles-containing vaccine (MCV) increased from 72% to 86%, then declined to 81% in 2021 during the COVID-19 pandemic, representing the lowest coverage since 2008. In 2022, first-dose MCV coverage increased to 83%. Only one half (72) of 144 countries reporting measles cases achieved the measles surveillance indicator target of two or more discarded cases per 100,000 population in 2022. During 2021-2022, estimated measles cases increased 18%, from 7,802,000 to 9,232,300, and the number of countries experiencing large or disruptive outbreaks increased from 22 to 37. Estimated measles deaths increased 43% during 2021-2022, from 95,000 to 136,200. Nonetheless, an estimated 57 million measles deaths were averted by vaccination during 2000-2022. In 2022, measles vaccination coverage and global surveillance showed some recovery from the COVID-19 pandemic setbacks; however, coverage declined in low-income countries, and globally, years of suboptimal immunization coverage left millions of children unprotected. Urgent reversal of coverage setbacks experienced during the COVID-19 pandemic can be accomplished by renewing efforts to vaccinate all children with 2 MCV doses and strengthening surveillance, thereby preventing outbreaks and accelerating progress toward measles elimination.

Understanding and explaining the link between anthroposophy and vaccine hesitancy: a systematic review

BACKGROUND

Due to low vaccination uptake and measles outbreaks across Europe, public health authorities have paid increasing attention to anthroposophic communities. Public media outlets have further described these communities as vaccine refusers or "anti-vaxxers". The aim of this review was to understand the scope of the problem and explore assumptions about vaccination beliefs in anthroposophic communities. For the purpose of this review, we define anthroposophic communities as people following some/certain views more or less loosely connected to the philosophies of anthroposophy. The systematic review addresses three research questions and (1) collates evidence documenting outbreaks linked to anthroposophic communities, (2) literature on vaccination coverage in anthroposophic communities, and (3) lastly describes literature that summarizes theories and factors influencing vaccine decision-making in anthroposophic communities.

METHODS

This is a systematic review using the following databases: Medline, Web of Science, Psycinfo, and CINAHL. Double-blinded article screening was conducted by two researchers. Data was summarized to address the research questions. For the qualitative research question the data was analysed using thematic analysis with the assistance of Nvivo12.0.

RESULTS

There were 12 articles documenting 18 measles outbreaks linked to anthroposophic communities between the years 2000 and 2012. Seven articles describe lower vaccination uptake in anthroposophic communities than in other communities, although one article describes that vaccination coverage in low-income communities with a migrant background was lower than in the anthroposophic community they studied. We found eight articles examining factors and theories influencing vaccine decision making in anthroposophic communities. The qualitative analysis revealed four common themes. Firstly, there was a very broad spectrum of vaccine beliefs among the anthroposophic communities. Secondly, there was a consistent narrative about problems or concerns with vaccines, including toxicity and lack of trust in the system. Thirdly, there was a strong notion of the importance of making individual and well-informed choices as opposed to simply following the masses. Lastly, making vaccine choices different from public health guidelines was highly stigmatized by those outside of the anthroposophic community but also those within the community.

CONCLUSION

Continuing to further knowledge of vaccine beliefs in anthroposophic communities is particularly important in view of increasing measles rates and potential sudden reliance on vaccines for emerging diseases. However, popular assumptions about vaccine beliefs in anthroposophic communities are challenged by the data presented in this systematic review.

Global genetic diversity of measles virus (Paramyxoviridae: Morbillivirus: Morbillivirus hominis): historical aspects and current state

Monitoring the circulation of the measles virus and studying its genetic diversity is an important component of the measles elimination program. A methodological approach to molecular genetic studies and their interpretation in the measles surveillance was developed in the early 2000s. During its development, clear areas of circulation of each genotype of the virus were identified, therefore, the determination of viruses' genotypes was proposed to monitor circulation and identify transmission pathways. However, in the future, due to a significant decrease in the number of active genotypes, an approach based on sub-genotyping was proposed: determining not only the genotype of the virus, but also its genetic lineage/genetic variant. The Global Measles and Rubella Laboratory Network (GMRLN) systematically monitors the circulation of the measles virus at the sub-genotypic level, depositing the results in a specialized database MeaNS2. It is this database that is the most complete and reliable source of information about the genetic characteristic of measles viruses. This review presents both historical information and the latest data on the global genetic diversity of the measles virus.

Attack rate, case fatality rate and determinants of measles infection during a measles outbreak in Ethiopia: systematic review and meta-analysis

BACKGROUND

Although Ethiopia is working towards measles elimination, a recurrent measles outbreak has occurred. To take appropriate measures, previously, many fragmented and inconsistent outbreak investigations were done, but there is no consolidated evidence on attack rate, case fatality rate, and determinants of measles infection during the measles outbreak. This systematic review and meta-analysis aimed to identify cumulative evidence on attack rate, case fatality rate, and determinants of measles infection during the outbreak.

METHODS

A systematic literature review and Meta-analysis was used. We searched Google Scholar, Medline/PubMed, Cochrane/Wiley Library, EMBASE, Science Direct, and African Journals Online databases using different terms. Investigations that applied any study design, data collection- and analysis methods related to the measles outbreak investigation were included. Data were extracted in an Excel spreadsheet and imported into STATA version 17 software for meta-analysis. The I2 statistics were used to test heterogeneity, and 'Begg's and 'Egger's tests were used to assess publication bias. The odds ratio (OR) with a 95% confidence interval (CI) was presented using forest plots.

RESULTS

Eight measles outbreak investigations with 3004 measles cases and 33 deaths were included in this study. The pooled attack rate (A.R.) and case fatality rate were 34.51/10,000 [95% CI; 21.33-47.70/10,000] population and 2.21% [95% CI; 0.07-2.08%], respectively. Subgroup analysis revealed the highest attack rate of outbreaks in the Oromia region (63.05 per 10,000 population) and the lowest in the Amhara region (17.77 per 10,000 population). Associated factors with the measles outbreak were being unvaccinated (OR = 5.96; 95% CI: 3.28-10.82) and contact history (OR = 3.90; 95% CI: 2.47-6.15).

CONCLUSION

Our analysis revealed compelling evidence within the outbreak descriptions, highlighting elevated attack and case fatality rates. Measles infection was notably linked to being unvaccinated and having a contact history. Strengthening routine vaccination practices and enhancing contact tracing measures are vital strategies moving forward.

Measles immunity gaps among children and adolescents with HIV in Zambia despite high measles vaccination and antiretroviral therapy coverage

OBJECTIVE

The study objective was to identify measles and rubella immunity gaps among people with HIV (PWH) in Zambia despite high measles vaccine coverage and widespread access to antiretroviral therapy.

DESIGN

Nationally representative cross-sectional serosurvey using biorepository specimens.

METHODS

Blood specimens collected in the Zambia Population HIV Impact Assessment survey (ZAMPHIA) of 2016 were tested for measles and rubella immunoglobulin G (IgG) antibodies by enzyme immunoassay. Hierarchical generalized additive models were fit to characterize age-specific measles and rubella seroprevalence profiles by HIV infection status. Log-binomial regression was performed to identify factors associated with seronegativity.

RESULTS

Of the 25 383 specimens, a subsample of 11 500 were selected and 9852 (85%) were successfully tested. Measles seroprevalence was lower among PWH compared with HIV-uninfected individuals until approximately 30 years of age. Among children younger than the age of 10 years, measles seroprevalence was 47.2% [95% confidence interval (CI): 32.7, 61.7] in PWH and 76.4% (95% CI: 74.9, 78.0) in HIV-uninfected children in same age category. In contrast, rubella seroprevalence was higher among PWH than HIV-uninfected individuals, particularly for children younger than 10 years (68.6% vs. 44.3%, P  < 0.001). Having a detectable viral load was associated with being measles seronegative (adjusted prevalence ratio 0.15, 95% CI: 0.06, 0.38).

CONCLUSIONS

These results from a nationally representative serosurvey demonstrate persistence of measles immunity gaps among PWH younger than 30 years of age. There is need to implement the World Health Organization's recommendation to revaccinate children living with HIV against measles following immune reconstitution with antiretroviral therapy to protect these children and prevent measles outbreaks.

Prevalence and factors associated with immunization coverage among children under five years in Mohamed Mooge health center, Hargeisa, Somaliland: a cross-sectional study

BACKGROUND

Routine immunization contributes greatly to reduction in mortality from vaccine preventable diseases among children. The Somaliland Demographic and Health survey, 2020 revealed that only 13.7% of children in Marodijeh (Hargeisa) region had received all recommended vaccines, which is far below the World Health Organization (WHO) target of 80%. We therefore, assessed factors associated with immunization coverage among children under five years at Mohamed Mooge Health Center in Hargeisa, Somaliland.

METHODS

Institutional based cross-sectional study was conducted on 174 systematically sampled, consented mothers that visited Mohamed Mooge Health Center for antenatal care during December 2022 to May 2023. Data was collected using a structured questionnaire. Data was analysed using SPSS and the relationship between dependent and independent variables was checked chi-square test at p ≤ 0.05. Finally, candidate variables were tested by using multivariate logistic regression in order to control potential confounders and the result was presented using AOR and 95% confidence interval. Model fitness was checked using Hosmer-Lemeshaw goodness of fit test with P > 0.05 for fitness. Multicollinearity between variables was checked using correlation coefficients at 0.80 or higher.  RESULT: Among 174 study participants, the prevalence of overall vaccine completion in this study was 55.3%. Women who had being aware about childhood immunization on BCG vaccination (AOR = 3.887; 95% CI: 1.275, 6.844), pentavalent (AOR = 11.385; 95% CI: 5.424-14.464), and measles (AOR = 3.074; 95% CI: 1.822-6.130) had higher odds of having immunized their children. Mothers who had employment had higher odds of having their children immunized against measles (AOR = 4.069; 95% CI: 1.822-6.130) compared to those who had not.

CONCLUSIONS

Full immunization coverage was lower than the target set by the World Health Organization in this study area. The current study revealed that, the mother's awareness of childhood vaccinations on BCG, pentavalent, measles and employment status of mothers were positively associated with immunization coverage. To promote vaccination coverage, the government should implement a national awareness campaign on childhood immunization and increase the number of outreach services.

Progress Toward Measles and Rubella Elimination - Indonesia, 2013-2022

In 2019, Indonesia and the other countries in the World Health Organization South-East Asia Region adopted the goal of measles and rubella elimination by 2023. This report describes Indonesia's progress toward measles and rubella elimination during 2013-2022. During this period, coverage with a first dose of measles-containing vaccine (MCV) decreased from 87% to 84%, and coverage with a second MCV dose decreased from 76% to 67%. After rubella vaccine was introduced in 2017, coverage with the first dose of rubella-containing vaccine increased approximately fivefold, from 15% in 2017 to 84% in 2022. During 2013-2021, annual reported measles incidence decreased by 95%, from 33.2 to 1.4 cases per million population; reported rubella incidence decreased 89%, from 9.3 to 1.0 cases per million population. However, a large surge in measles and rubella cases occurred in 2022, with a reported measles incidence of 29 cases per million and a reported rubella incidence of 3 per million, primarily related to disruption in immunization services caused by the COVID-19 pandemic. In 2022, approximately 26 million children (an estimated 73% of the target population) received a combined measles- and rubella-containing vaccine during supplementary immunization activities completed in 32 provinces. Progress toward measles and rubella elimination in Indonesia has been made; however, continued and urgent efforts are needed to restore routine immunization services that were adversely affected by the COVID-19 pandemic and close immunity gaps to accelerate progress toward measles and rubella elimination.

Characteristics of Anti-Measles Immunity in Lung Transplant Candidates

Measles has not yet been eradicated; therefore, its outbreaks are still reported throughout the world. Like any infection, measles is dangerous for immunocompromised patients. Levels of anti-measles IgG antibodies were measured in 157 patients aged 17 to 72, who were placed on the lung transplant waiting list. Measurements were undertaken by enzyme-linked immunosorbent assay (ELISA) using the VectoMeasles-IgG kit (Russia). The proportion of patients seronegative for measles was 19% (30/157). Correlation was detected between patients' age and their levels of anti-measles antibodies, with higher proportions of patients having undetectable titers (25.5-28.9%) or low antibody levels (38.3-44.4%) in the young age groups (17-29 and 30-39 years old). There were no differences between male and female patients in levels of anti-measles antibodies or in the proportion of seronegative individuals. Analyses of antibody levels with regard to type of disease revealed the highest rate of seronegative results in cystic fibrosis patients (34.4%, 11/32). Overall, 19% of lung transplant candidates, mostly young people and cystic fibrosis patients, did not have protective immunity against measles.

Susceptibility of nursery teachers to measles, rubella, varicella and mumps in Japan

BACKGROUND

A guideline published in 2018 by the Ministry of Health, Labour and Welfare stipulated confirmation of the vaccine history of nursery staff members.

OBJECT

This study was conducted to elucidate nursery teachers' vaccine and infection histories for measles, mumps, rubella, and varicella through survey responses.

METHOD

After sending questionnaires through the mail to 5000 nursery teachers in November 2022, we received responses through December 2022. We measured the proportion of susceptibility in three ways. Additionally, we compared the proportions of susceptibility by disease by age class.

RESULTS

After receiving 1620 responses in all, the data of 1229 respondents under 50 years old were analyzed. Under the broad definition by which "no answer" was also regarded as unvaccinated or uinfected as well as "unknown," the proportions of susceptibility for measles, rubella, and varicella were higher: 22-23%. For mumps, the proportion was 42%. For varicella, they were 31% for respondents in their 30 s, and 14% for respondents in their 40 s. For mumps, the respective values were 58% and 26%.

DISCUSSION

Respondents assessed for this study were less susceptible and unknown in comparison with earlier studies investigating health care workers, school teachers, university students, and pregnant women.

CONCLUSION

The survey revealed that measles and rubella susceptibility was higher among respondents in their 30 s. However, it was higher for varicella and mumps among respondents in their 20 s.

Maternally transmitted anti-measles antibodies, and susceptibility to disease among infants in Chandigarh, India: A prospective birth cohort study

Prior to the age of measles vaccination, infants are believed to be protected against measles by passively transferred maternal antibodies. However, the quantity and quality of such protection have not been well established in the Indian setting. We undertook this study to characterize the transfer and decline in maternal anti-measles antibodies among infants, and determine their susceptibility to measles. In this population-based, birth-cohort study, we enrolled pregnant women and their newborn infants, from a catchment area of 30 Anganwadis in Chandigarh, India. We collected maternal blood at delivery, and infant blood samples at birth, and 3, 6, and 9 months of age. Anti-measles IgG antibodies were measured using quantitative ELISA. We assessed antibody decline using log-linear models. In total, 428 mother-infant dyads were enrolled, and data from 413 dyads were analyzed. At birth, 91.5% (95% CI: 88.8, 94.2) of infants had protective antibody levels, which declined to 26.3% (95% CI: 21.0%, 31.9) at 3 months, 3.4% (95% CI: 0.9, 5.9) at 6 months, and 2.1% (95% CI: 0.1, 4.1) at 9 months. Younger mothers transferred lower levels of antibodies to their infants. We concluded that the majority of infants are susceptible to measles as early as three months of age, much earlier than their eligibility to receive measles vaccination.

Seroprevalence of Measles, Mumps, Rubella, and Varicella-Zoster Virus and Seroresponse to the Vaccinations in Adult Solid Organ Transplant Candidates

BACKGROUND

Updating live vaccines such as measles, mumps, rubella, and varicella (MMRV) is an important step in preparing patients for solid organ transplant (SOT) to prevent morbidity from these preventable diseases. However, data for this approach are scarce. Thus, we aimed to describe the seroprevalence of MMRV and the efficacy of the vaccines in our transplant center.

METHODS

Pre-SOT candidates >18 y of age were retrospectively retrieved from SOT database in Memorial Hermann Hospital Texas Medical Center. MMRV serologies are routinely screened at the time of pretransplant evaluation. We divided patients into 2 groups: MMRV-positive group versus MMRV-negative group, patients with positive all MMRV serologies and with negative immunity to at least 1 dose of MMRV, respectively.

RESULTS

A total of 1213 patients were identified. Three hundred ninety-four patients (32.4%) did not have immunity to at least 1 dose of MMRV. Multivariate analysis was conducted. Older age (odds ratio [OR]: 1.04) and liver transplant candidates (OR: 1.71) were associated with seropositivity. Previous history of SOT (OR: 0.54) and pancreas/kidney transplant candidates (OR: 0.24) were associated with seronegativity. Among 394 MMRV seronegative patients, 60 patients received 1 dose of MMR vaccine and 14 patients received 1 dose of varicella-zoster virus vaccine without severe adverse events. A total of 35% (13/37) of patients who had follow-up serologies did not have a serological response.

CONCLUSIONS

A significant number of pre-SOT candidates were not immune to at least 1 dose of MMRV. This highlights the importance of MMRV screening and vaccinations pre-SOT. Postvaccination serological confirmation should be performed to evaluate the necessity for a second dose.

Differential diagnosis of fever and rash cases negative for measles and rubella to complement surveillance activities

In the quest to eliminate measles virus (MV) and rubella virus (Ruv), every suspected case must be properly identified and diagnosed. Since 2017, in Milan (Italy), a total of 978 measles and rubella suspected cases (fever and rash) were investigated and 310 were not laboratory confirmed (discarded cases). To improve surveillance activities, we investigated the presence in discarded cases of 8 other viral pathogens commonly associated with rash: human herpesvirus 6 (HHV-6) and 7 (HHV-7), parvovirus B19 (B19V), enterovirus (EV), Epstein-Barr virus (EBV), human adenovirus (HAdV), cytomegalovirus (HCMV), and SARS-CoV-2. Differential diagnosis was carried out on 289 discarded cases by multiplex real-time PCR assays. At least one pathogen was detected in 188 cases (65.1%) with HHV-7 being the most frequently detected virus. No difference in the number of detected infections overtime was observed and infections were identified in all age groups. As expected, most HHV-6, EV, HAdV, and HCMV-positive cases were found in children aged 0-4 years and HHV-7 was most frequent in the 15-39 age group. In light of the World Health Organization measles elimination goal, the introduction of laboratory methods for differential diagnosis is required for the final classification of clinically compatible cases. The used screening panel allowed us to increase the percentage of virus-positive cases to 87.5%, allowing us to clarify viral involvement and epidemiology, improve diagnosis, and strengthen surveillance activities. As all investigated pathogens were detected, this diagnostic panel was a suitable tool to complement MV and RuV surveillance activities.

Measles vaccination and reduced child mortality: Prevention of immune amnesia or beneficial non-specific effects of measles vaccine?

Measles vaccine (MV) has been observed to reduce all-cause mortality more than explained by prevention of measles infection. Recently, prevention of "measles-induced immune amnesia" (MIA) has been proposed as an explanation for this larger-than-anticipated beneficial effect of measles vaccine (MV). According to the "MIA hypothesis", immune amnesia leads to excess non-measles morbidity and mortality, that may last up to five years after measles infection, but may be prevented by MV. However, the benefits of MV-vaccinated children could also be due to beneficial non-specific effects (NSEs) of MV, reducing the risk of non-measles infections (The "NSE hypothesis"). The epidemiological studies do provide some support for MIA, as exposure to measles infection before 6 months of age causes long-term MIA, and over 6 months of age for 2-3 months. However, in children over 6 months of age, the MIA hypothesis is contradicted by several epidemiological patterns: First, in community studies that adjusted for MV status, children surviving acute measles infection had lower mortality than uninfected controls (44%(95%CI: 0-69%)). Second, in six randomised trials and six observational studies comparing MV-vaccinated and MV-unvaccinated children, the benefit of MV changed minimally from 54%(43-63%) to 49%(37-59%) when measles cases were censored in the survival analysis, making it unlikely that prevention of measles and its long-term consequences explained much of the reduced mortality. Third, several studies conducted in measles-free contexts still showed significantly lower mortality after MV (55%(40-67%)). Fourth, administration of MV in the presence of maternal measles antibody (MatAb) is associated with much stronger beneficial effect for child survival than administration of MV in the absence of MatAb (55%(35-68%) lower mortality). The MIA hypothesis alone cannot explain the strongly beneficial effects of MV on child survival. Conversely, the hypothesis that MV has beneficial non-specific immune training effects is compatible with all available data. Consideration should be given to continuing MV even when measles has been eradicated.

Measles Virus and the Central Nervous System: An Update

MEASLES VIRUS AND ASSOCIATED CENTRAL NERVOUS SYSTEM

Sequelae Renee Buchanan, Daniel J. Bonthius Seminars in Pediatric Neurology Volume 19, Issue 3, September 2012, Pages 107-114 Worldwide, measles remains one of the most deadly vaccine-preventable diseases. In the United States, enrollment in the public schools requires that each child receives 2 doses of measles-containing vaccine before entry, essentially eliminating this once endemic disease. Recent outbreaks of measles in the United States have been associated with importation of measles virus from other countries and subsequent transmission to intentionally undervaccinated children. The central nervous system complications of measles can occur within days or years of acute infection and are often severe. These include primary measles encephalitis, acute postinfectious measles encephalomyelitis, measles inclusion body encephalitis, and subacute sclerosing panencephalitis. These measles associated central nervous system diseases differ in their pathogenesis and pathologic effects. However, all involve complex brain-virus-immune system interactions, and all can lead to severe and permanent brain injury. Despite better understanding of the clinical presentations and pathogenesis of these illnesses, effective treatments remain elusive.

Factors associated with a measles outbreak in three health districts of Cameroon in 2019: a cross-sectional study

Introduction

measles is an infectious viral disease that affects susceptible individuals of all ages. It is a leading cause of death among young children globally due to suboptimal vaccination coverage. In 2019, measles outbreaks affected several parts of the world, including three health districts (HDs) of Cameroon's South West Region (SWR) experiencing armed conflict. Herein, we assessed the factors associated with the outbreak in the SWR.

Methods

we conducted a comparative study from March to August 2020. Data on study participants were compared between the three HDs that experienced a measles outbreak and three other HDs of the region that reported a case of measles but did not get into an outbreak. Records on vaccination between 2015 and 2019 were reviewed.

Results

information was obtained from 56 participants with known measles status, 32 from outbreak districts, and 24 from non-outbreak districts. The population in the outbreak group was more likely to have traveled from an area in a measles outbreak (OR 2, 95%CI 1.1-11.20). There was a suboptimal availability of measles vaccines in both categories of districts compared to the needs, and there was a downward trend in vaccination coverage in both groups. In addition, vaccines were more exposed to extreme temperatures in HDs with the outbreak (P<0.01) from 2015 to 2019. We found no statistically significant difference between both groups concerning the preexisting comorbidities of participants.

Conclusion

there is an urgent need to improve the cold chain and intensify vaccination activities in these districts.

A Single-Center Evaluation of Pediatric Measles Cases in Istanbul, Türkiye, in 2019

Although measles can be prevented and eliminated by vaccination, it is a highly contagious viral disease that can lead to serious complications, disability, and death. The aim of this retrospective study was to evaluate the characteristics of measles cases in a single center. All children with clinically suspected measles who attended the Pediatric Clinic at Esenler Maternity and Child Health Hospital in Istanbul, Türkiye, between January 1 and June 30, 2019 were included in the analysis. None of the children with measles were fully vaccinated. The incidence and duration of conjunctivitis were significantly higher in the unvaccinated group than in the partially vaccinated group (P = 0.027 and P = 0.019, respectively). Unvaccinated patients had a significantly lower median leukocyte count (P = 0.019) and significantly higher median C-reactive protein level (P = 0.021). The vitamin A level and leukocyte count were moderately positively correlated (r = 0.698; P = 0.008). Children should be fully vaccinated in order to prevent measles.

Entangled epidemics: tackling vaccine-preventable diseases in the era of frequent epidemics in Africa

Whilst the largely limited health system and funds are already overstretched while responding to multiple epidemics, ongoing vaccine-preventable diseases (VPD) including polio and measles continue to be a public health threat and expose the weaknesses of the public health system in many African countries. The surge in VPD outbreaks during epidemics appears to be a common trend in Africa, often due to reduced vaccination coverage. The World Health Organization reported that, in 2021, nearly 25 million children missed their first measles dose, 5 million more than in 2019. The drop in childhood immunizations was partly attributed to the COVID-19 pandemic which has caused significant interruption in public health services delivery and reduced vaccination coverage. Vaccines help reduce the incidence of VPD. Therefore, effective VPD outbreak response mechanisms and strategies that include ramping up catch-up campaigns for immunization during epidemic troughs including the provision of vaccines outside clinics as well as assessing newer vaccine delivery models during pandemics are essential to minimize the impact of VPD outbreaks during emerging epidemics. Ensuring access to vaccines to address outbreaks and provide supplemental vaccination is essential if we are to be a VPD-free region.

Lessons from the re-emergence of imported measles cases following the COVID-19 pandemic in Victoria, Australia

Introduction

Australia was declared to have eliminated endemic measles in 2014; however, imported cases continue to pose a threat of outbreaks. International travel restrictions during the coronavirus disease 2019 (COVID-19) pandemic led to a rapid decline in measles cases. The re-opening of the Australian international border to measles endemic regions returns the threat of outbreaks, which may be further compounded by disruptions in routine vaccinations during the COVID-19 pandemic. We consider lessons learned from the public health response to recent measles cases.

Methods

This case series includes all confirmed measles cases meeting the national case definition reported to the Victorian Government Department of Health (the Department) between 1 January and 31 December 2022. The Department conducted active case finding and contact tracing of all cases in line with national guidelines. Cases were descriptively analysed.

Results

In 2022, six of the seven measles cases reported in Australia occurred in Victoria, all of whom resided in Australia and acquired their infection overseas. Three cases were unlinked, and three formed an epidemiologically-linked household cluster. One case was partially vaccinated, one was not eligible for vaccination, one had unknown vaccination status, and three were unvaccinated, one of whom was under 12 months old but would have been eligible for vaccination prior to travel to endemic regions. None of the cases led to secondary transmission within Australia.

Discussion

Following the COVID-19 pandemic, measles importations have re-commenced in Victoria. Although few measles cases occurred in 2022 and none resulted in onwards transmission, imported measles cases remain complex and require substantial public health follow-up. Delays in case diagnosis and flight contact tracing pose a significant risk for outbreaks of measles. Public health interventions are needed to maintain high vaccination rates, improve contact tracing, and ensure public health authorities and healthcare providers can rapidly identify and respond to imported measles cases.

[Experience with the use of pharmacopoeial reference material for the activity of measles vaccine]

INTRODUCTION

Due to the increased incidence of measles in Russia and in many other regions of the world, vaccines for the measles prevention are especially in demand. Ensuring the quality of the measles vaccine for effective disease prevention is within the scope of the tasks of the state policy of our country.

OBJECTIVE

Evaluation of the experience of using a pharmacopoeial standard material of measles vaccine activity for measurement of the specific activity of the measles virus in vaccines with a measles component that are used in the Russian Federation for measles prevention.

MATERIALS AND METHODS

The object of the study was the Pharmacopoeia reference material (PRM) of the activity of the live measles vaccine of series 10. The activity of PRM was analyzed when determining the specific activity of the measles, mumps-measles and combined vaccines for the prevention of measles, rubella and mumps, as well as based on the materials of the summary protocols for the production of these vaccines.

RESULTS

The titer of the measles virus in the PRM for each determination of the specific activity of the measles virus in vaccines in the Scientific Centre for Expert Evaluation of Medicinal Products in 2021-2022, as well as according to the summary production protocols, was within the boundaries of the certified value (4.63 ± 0.5) lgTCD50/0.5 ml, and the test results met the acceptance criteria in accordance with the requirements of regulatory documentation. During the observation period, the average value of the PRM titer (4.61 lgTCD50/0.5 ml) practically did not differ compared to the average value of the certified characteristics of the PRM, the standard deviation of the mean value of the measles virus titer in the PRM did not exceed 0.15 lgTCD50, which indicated the stability of the analytical work at the enterprise and in IC.

CONCLUSION

The data obtained indicate the stable activity of PRM, the correctness of the determination of the measles virus titer in the vaccination dose of the vaccine, and the validity of the method for monitoring the specific activity of the measles virus in vaccines.

Exploring data trends and providers' insights on measles immunization uptake in south-west Nigeria

Introduction

measles outbreak remains a recurring episode and continues to be responsible for millions of deaths globally every year. This study examines measles immunization coverage and uncovers barriers and enablers to effective provision and uptake of measles immunization services from the supply end and provider´s perspective in a developing nation´s context.

Methods

the study employed a mixed-method approach to explore trends and patterns of measles immunization uptake in Ekiti State-a state in the southwestern region of Nigeria-utilizing DHIS 2014 - 2019 data of 789,518 under 1-year children and complemented the quantitative study with key informant interviews from appointed Immunization Officers in the state. Using deductive methods, we thematically analyzed the interview data using NVivo version 12 while STATA 16 was used to analyze the quantitative data.

Results

the annualized measles immunization coverage ranged between 49% and 86% from 2014 to 2019, which is below the WHO set threshold for measles infection prevention. Caregiver, geographical, human, and infrastructural factors were elicited as barriers, while potential enablers include increased public engagement and enhanced media involvement.

Conclusion

while programmatic efforts are being improved nationally to drive up the uptake, this study provides baseline information for benchmarking the subsequent level of efforts and recommends improved collaboration across contextually similar states to promote program efficiency. The results can inform policy and program development, execution and direct future research on measles immunization to address uptake challenges at both local and central administration levels, especially in the aspect of surveillance and monitoring.

Rubella virus genotype 2B endemicity and related utility of serum-based molecular characterization in Uganda

There are 13 globally recognized rubella virus genotypes of which only 2 (1E and 2B) have been detected recently. The largest percentage of all reported rubella virus sequences come from China and Japan with Africa reporting limited data. In a bid to address the lack of rubella genotype data in Uganda and the World Health Organization Africa region, we sought to characterize rubella viruses retrospectively using sera collected from suspected measles patients that turned out rubella IgM positive.Seven sequences belonging to genotype 2B sub-lineage 2B-L2c were obtained. These sequences clustered with other genotype 2B sequences previously reported from Uganda. None of the other genotypes (1E and 1G) reported from Uganda in the earlier years were detected. In addition, none of the sequences were obtained after the introduction of the measles-rubella containing vaccine. The above highlight the need for continuous rubella virological surveillance to confirm interruption of endemic rubella genotype circulation.

Epidemiology of confirmed measles virus cases, surveillance, incidence, and associated factors in Eritrea: 18-year retrospective analysis

Background

Despite the outstanding measles vaccine coverage (MVC) in Eritrea, sporadic outbreaks are not uncommon. Therefore, understanding the incidence of laboratory-confirmed measles virus cases, related factors, and spatial inequalities in testing and surveillance remains crucial. In this analysis, we evaluated the incidence and spatiotemporal distribution of measles in Eritrea. An evaluation of the factors associated with measles vaccination and IgM positive (+) febrile rash was also undertaken.

Methods

A retrospective (period: 2002-2020) study was carried out by abstracting data from the integrated disease surveillance and response database (IDSR). Data was analyzed using descriptive statistics and binary logistic regression. Spatial variability and distribution of confirmed cases was evaluated using ArcGIS Pro version 3.0.1.

Results

In total, 9,111 suspected cases, 2,767 [1,431 (51.7%) females] were serologically tested. The median (IQR) age, minimum-maximum age were 7 years (IQR: 4-14 years) and 1 month-97 years, respectively. Among the 608(21.9%) laboratory-confirmed cases, 534 (87.8%) were unvaccinated and 53 (9.92%) were < 1 year old. The crude incidence rate for MV was 14/100,000 persons. The age-specific positivity rate per 100,000 suspected cases tested was 21.5 with individuals >30 years presenting with the highest rates (69.9/100,000). Higher odds (OR) of MV test positivity was associated with age at onset - higher in the following age-bands [10-14 years: OR = 1.6 (95%CI, 1.1-2.2, value of p = 0.005); 15-29 years: OR = 7.0 (95%CI, 5.3-9.2, value of p = 0.005); and > =30 years: OR = 16.7 (95%CI, 11.7-24) p < 0.001]. Other associations included: Address - higher in Anseba (OR = 2.3, 95%CI: 1.7-3.1, value of p<0.001); Debub (OR = 2.7, 95%CI: 1.9-3.9, value of p < 0.001); Gash-Barka (OR = 15.4, 95%CI: 10.9-21.7, value of p < 0.001); Northern Red Sea (OR = 11.8, 95%CI: 8.5-16.2, value of p < 0.001); and Southern Red Sea (OR = 14.4, 95%CI: 8.2-25.2, value of p < 0.001). Further, test positivity was higher in health centers (OR = 2.5, 95%CI: 1.9-3.4, value of p < 0.001) and hospitals (OR = 6.8, 95%CI: 5.1-9.1, value of p < 0.001). Additional factors included vaccination status - higher in the unvaccinated (OR = 14.7, 95%CI: 11.4-19.1, value of p < 0.001); and year of onset of rash - (higher >2015: OR = 1.4, 95%CI: 1.1-1.7, value of p<0.001). Uptake of measles vaccine associated with a similar complement of factors.

Conclusion

In large part, efforts to eliminate measles in Eritrea are hindered by disparities in vaccine coverage, under-surveillance, and low vaccination rates in neighboring countries. Enhanced surveillance and regional micro planning targeting hard-to-reach areas can be an effective strategy to improve measles elimination efforts in Eritrea.

Immunization in the Eastern Mediterranean Region: some signs of post-COVID-19 recovery, but more work ahead

Every year, WHO and UNICEF estimate the immunization coverage for 195 Member States, based on reported data and independent coverage surveys (1,2). These estimates indicate progress in reaching children with life-saving vaccines while identifying coverage gaps (3). The 2022 estimates were much awaited, given that the COVID-19 pandemic caused a setback in coverage (1). Overall, there are encouraging signs of recovery in the WHO Eastern Mediterranean Region (EMR). For example, coverage of the third dose diphtheria-pertussis-tetanus containing vaccine (DTPcv3) and the second dose measles containing vaccine (MCV2), both almost restored or exceeded their 85% and 76% pre-pandemic 2019 levels, respectively (1). However, there are disparities across countries. Low-income countries with fragile, weak health systems and those in conflict situation are lagging. The number of children who missed their routine first dose of measles immunization increased from 3 million in 2019 to 3.16 million in 2022 (1). This underperformance, along with the accumulated immunity gap in 2020-2021, exposes us to the risk of preventable deadly outbreaks.