Genome-wide determinants of cellular immune responses to mumps vaccine

BACKGROUND

We have previously described genetic polymorphisms in candidate genes that are associated with inter-individual variations in antibody responses to mumps vaccination. To expand upon our previous work, we performed a genome-wide association study (GWAS) to discover host genetic variants associated with mumps vaccine-induced cellular immune responses.

METHODS

We performed a GWAS of mumps-specific immune response outcomes (11 secreted cytokines/chemokines) in a cohort of 1,406 subjects.

RESULTS

Among the 11 cytokine/chemokines we studied, four (IFN-γ, IL-2, IL-1β, and TNFα) demonstrated GWAS signals reaching genome-wide significance (p < 5 × 10-8). A genomic region (encoding Sialic acid-binding immunoglobulin-type lectins/SIGLEC) located on chromosome 19q13 (p < 5 × 10-8) was associated with both IL-1β and TNFα responses. The SIGLEC5/SIGLEC14 region contained 11 statistically significant single nucleotide polymorphisms (SNPs), including the intronic SIGLEC5 rs872629 (p = 1.3E-11) and rs1106476 (p = 1.32E-11) whose alternate alleles were significantly associated with decreased levels of mumps-specific IL-1β (rs872629, p = 1.77E-09; rs1106476, p = 1.78E-09) and TNFα (rs872629, p = 1.3E-11; rs1106476, p = 1.32E-11) production.

CONCLUSIONS

Our results suggest that SNPs in the SIGLEC5/SIGLEC14 genes play a role in cellular and inflammatory immune responses to mumps vaccination. These findings motivate further research into the functional roles of SIGLEC genes in the regulation of mumps vaccine-induced immunity.

Mumps vaccine hesitancy: Current evidence and an evidence-based campaign in Japan

BACKGROUND

Mumps is still endemic in Japan because mumps vaccination is voluntary. In this study, we investigated associations of parental socioeconomic status, family structure, and knowledge/belief about mumps and mumps vaccine with parental decision to vaccinate their children. We also evaluated effectiveness of a campaign based on survey results.

METHODS

We conducted a cross-sectional survey of parents with children aged 1-6 years attending preschools or kindergartens in Tokamachi City, Japan. We assessed the association of parental factors with their decision to vaccinate their children using multivariable logistic regression analyses. We designed a campaign based on the survey results, and compared the number of annual vaccinations at Tokamachi Hospital per the child population aged 1-6 years in Tokamachi City before and after the campaign using a trend test.

RESULTS

In total, 1391 of 1617 (86%) eligible parents completed the survey. Among these parents, 229 (16%) vaccinated their children. In multivariable analyses, higher parental education [odds ratio (OR) = 2.21; 95% CI, 1.59-3.08; P < 0.001], greater knowledge about mumps and the mumps vaccine (OR = 1.88; 95% CI, 1.60-2.21; P < 0.001), and living without grandparents (OR = 1.44; 95% CI, 1.05-1.99; P = 0.024) were significantly associated with parental decision to vaccinate their children. The number of annual vaccinations per the child population significantly increased following the campaign (P < 0.001).

CONCLUSION

Our study showed several sociodemographic factors significantly associated with mumps vaccination. Further research is needed to examine the relevance of our findings to the uptake of other voluntary vaccines among children.

Cost-effectiveness analyses of monovalent mumps vaccination programs for Japanese children

BACKGROUND

The most common preventative measure against mumps is vaccination with mumps vaccine. Over 122 countries have implemented mumps vaccine routine immunization programs, mostly via Measles-Mumps-Rubella (MMR) vaccine. In Japan, the unexpectedly high incidence of aseptic meningitis caused by mumps vaccine led to the discontinuation of the MMR national vaccination program in 1993, inadvertently resulting in the re-emergence of mumps. Plans of introducing monovalent mumps vaccine into routine vaccination schedule have become one of the emerging topics in health policy that has warranted the need in evaluating its value for money.

METHODS

We conducted cost-effectiveness analyses with Markov model and calculated incremental cost-effectiveness ratios (ICERs) of two different vaccination programs (a single-dose program at one-year-old, a two-dose program with second dose uptakes at five) compared to status quo from both payers' and societal perspectives. Transition probabilities and utility weights in estimating quality-adjusted life-year (QALY), and disease treatment costs were either estimated or obtained from literature. Costs per vaccination were assumed at ¥6140 (US$58;1US$ = ¥106).

RESULTS

Both programs reduce disease treatment costs compared to status quo, while the reduction cannot offset vaccination cost. ICER of either program is found to be under ¥5,000,000 (US$47,170)/QALY willingness-to-pay (WTP) threshold from either perspective. Results of probabilistic sensitivity analyses expressed by net monetary benefit indicated that at the WTP threshold, the acceptability is at 92.6% for two-dose vaccination program, 0% for single-dose vaccination program, and 7.4% for current no vaccination program. Two-dose program was optimal among the alternatives. One-way sensitivity analyses revealed that proportion of mumps-related hearing loss among mumps cases and vaccine effectiveness (VE) were key variables in changing the ICERs.

CONCLUSION

Routine vaccination program of single- and two-dose programs were cost-effective from both payers' and societal perspectives. Between the two, the two-dose vaccination program was observed to be more favorable.

Annual trends in adverse events following mumps vaccination in Japan: A retrospective study

BACKGROUND

In Japan, a monovalent mumps vaccine is provided on a voluntary basis. Due to public concerns over post-vaccination aseptic meningitis, the vaccination coverage is not high enough. The present study investigated the incidence of adverse events, including aseptic meningitis, after Torii strain-derived mumps vaccination.

METHODS

This retrospective, observational study used data collected by a vaccine manufacturer regarding adverse events following mumps vaccinations at medical institutions between 1992 and 2018. In addition, the number of Torii strain-derived mumps vaccines shipped each year was obtained. The incidence (per 100,000 doses) and 95% confidence intervals (CIs) were calculated for all adverse events and each adverse event, categorized as aseptic meningitis, encephalitis, mumps, mumps complications, and others.

RESULTS

During the study period, 8,262,121 mumps vaccine doses were shipped, and 688 subjects reported adverse events. The incidence for all adverse events (per 100,000 doses) was 8.33, and the incidence was 4.19 for aseptic meningitis, 0.33 for encephalitis, 0.80 for mumps, 0.25 for mumps complications, and 3.78 for others. The incidence of aseptic meningitis (per 100,000 doses) was 7.90 (95% CI: 5.61-10.18) between 1998 and 2000 but declined by half, to 3.91 (2.46-5.36), between 2001 and 2003. The most recent incidence (per 100,000 doses) of aseptic meningitis, for the period 2016 to 2018, was 2.78 (1.94-3.62).

CONCLUSION

The incidence of post-vaccination aseptic meningitis has declined significantly since 2001, and the incidence has remained stable at fewer than 3 cases per 100,000 doses since 2010. Multiple factors might have contributed to the decline in aseptic meningitis incidence, including (i) lowered misclassification of aseptic meningitis resulting from echovirus infection; (ii) changes in the vaccine manufacturing process in 2000; and (iii) publication in 2008 of the recommendation for vaccination of children at 1 year of age.

Live attenuated vaccine efficacy six months after intravenous immunoglobulin therapy for Kawasaki disease

BACKGROUND

Due to the presence of maternal passive antibodies, the measles vaccine is ineffective if administered before age 12-15 months. The optimal timing for administering a live attenuated vaccine (LAV) after intravenous immunoglobulin therapy (IVIG) for Kawasaki disease (KD) has not been fully investigated. The recommended interval between vaccination and IVIG therapy for KD differs by country. The present study aimed to evaluate efficacy of LAV six months after IVIG therapy for KD in Japan.

METHODS

The present, single-arm, prospective, interventional study included patients aged 6 months or older with no medical history of measles, rubella, varicella or mumps or vaccinations against these diseases. The subjects received these vaccinations for the first time at six months after IVIG therapy. Virus-specific IgG levels for each virus measured by EIA was examined at nine months after IVIG therapy. If the results were negative, the subjects received a booster vaccination at 12 months after IVIG therapy. The primary outcome was the prevalence of positivity for antibodies after the initial and booster vaccinations.

RESULTS

The present study enrolled 32 subjects, 31% of whom were female, with an average age of 10.8 (standard deviation 2.8) months at IVIG therapy. At six months after IVIG therapy, 9% and 6% of the subjects were seropositive for measles and varicella titers, respectively, but were seronegative for the mumps and rubella titers. The seroconversion rate for measles, mumps, rubella, and varicella after the initial vaccination was 88%, 6%, 78%, and 16%, respectively. The seroconversion rate after a booster vaccination was 100% for measles and rubella, 97% for mumps, and 77% for varicella.

CONCLUSIONS

The seroconversion rate was low for LAV at six months after a single dose of IVIG for KD, but seroconversion was achievable with a booster vaccination at 12 months.

CLINICAL TRIAL REGISTRATION

UMIN-CTR, UMIN000007174, https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000008452.

Differential durability of immune responses to measles and mumps following MMR vaccination

The development and wide-spread use of mumps vaccine resulted in a dramatic and sustained decrease in the incidence of mumps disease; however, since 2000, an increase in the size and number of mumps outbreaks in the United States and other countries has sparked renewed interest in the durability of mumps-specific immunity elicited by mumps vaccination. The most likely explanation for mumps cases in previously immunized persons may be secondary vaccine failure, or waning immunity. In the current study, we examined changes in markers of measles and mumps immunity at two timepoints, approximately 7 and 17 years after two-dose MMR-II® vaccination, in a cohort of 98 healthy adults. Our results indicate that mumps IgG titers exhibited a large and significant decline during this time period, while mumps neutralizing Ab titers were relatively stable. There was a similar discrepancy with measles-specific immune responses. For both pathogens, neutralizing antibody titers were fairly low and, given the length of time since vaccination, may have already declined. These data suggest that specific immune outcomes may wane at different rates and highlight our currently incomplete understanding of protective immune responses to mumps and measles.

Knowledge gaps persist and hinder progress in eliminating mumps

Mumps, a common childhood disease in the pre-vaccine era that causes swelling of the parotid salivary glands, can lead to orchitis, viral meningitis, and sensorineural deafness. While the incidence of disease decreased dramatically after the vaccine was added to standard vaccination schedules, the disease has made a substantial resurgence in recent years. As a result, it becomes critical to examine the factors involved in recurring outbreaks. Although low and incomplete vaccination coverage may be a key reason, it does not fully explain the issue due to the high rate of occurrence in populations with high vaccination coverage rates. Multiple studies suggest that waning immunity and secondary vaccine failure play a large role, the effects of which were previously masked by subclinical boosting. Significant knowledge gaps persist around the exact role and mechanism of waning immunity and demonstrate the need for more research in this area, as well as a reevaluation of mumps vaccine policy.

Mumps outbreaks: A problem in need of solutions

OBJECTIVES

To discuss what is presently known about recent mumps outbreaks and what solutions can be suggested to ensure more complete protection against mumps.

METHODS

PubMed was used to search for all of the studies published over the last 15 years using the key words "mumps" or "mumps virus" or "mumps vaccine". More than 1500 articles were found, but only those published in English or providing evidence-based data were included in the evaluation.

RESULTS

Prevention of mumps remains an unsolved problem. Available vaccines are effective but the protection they evoke declines over time. The use of booster doses can control outbreaks but it is not precisely defined whether they can prevent them. The rapid decline of antibody levels could limit the impact of the introduction of a third dose in the recommended immunization schedule. Furthermore, in most of the areas, mumps viral strains that are genetically different from those included in the vaccines are emerging and this might favour vaccine escape. However, also for this problem, its real relevance in favouring outbreak development is not precisely defined.

CONCLUSIONS

The true reasons for the development of mumps outbreaks in people with very high vaccination coverage are not clearly understood. The use of a booster dose or the preparation of vaccines containing the emerging serotypes are possible solutions, but both have some limitations. Further studies mainly devoted to improve our knowledge of the immune response to mumps vaccines are needed before long-term effective mumps vaccines can be prepared and outbreaks can be avoided.

[Evaluation on the short term effectiveness of two doses mumps-containing vaccine policy in Shandong, China]

Objective: To evaluate the effectiveness of mumps prevention and control after implementation of two doses mumps-containing combined vaccine (MuCV) policy by analyzing epidemiological characteristics of mumps and mumps antibody levels in general population. Methods: We obtained data on cases of mumps reported during 2004-2015 from National Notifiable Diseases Reporting System (NNDRS). Descriptive analysis methods were used to describe the epidemiological characteristics of mumps during 2004-2015. MuCV immunization information from 2005 to 2015 was obtained from the immunization information management system in Shandong Province. Antibody data of mumps in healthy people were from a cross-sectional survey according to the principle of stratified random sampling from 0 to 60 years old healthy people in 2015. Commercial ELISA kits were used to detect and quantify human IgG antibodies against mumps virus in sera, and the results were analyzed statistically. Results: The average incidence of mumps from 2004 to 2015 was 11.43/100 000 in Shandong. The incidence of mumps in the central region (14.64/100 000) was higher than that in the eastern and western regions (11.14/100 000, 11.33/100 000). The incidence of mumps was still high in 2009-2013 (stage of one-dose MuCV free, 16.07/100 000) with the highest incidence of 25.33/100 000 and 24.45/100 000 occurred in 2012 and 2013 and the cases were mainly 6 to 9 years old group (172.67/100 000). Since the second dose MuCV was introduced into NIP for 6 years old children in May 2013 in Shandong, the incidence of mump decreased significantly in 2014-2015 (7.81/100 000), especially in children of 6-8 years old who were vaccinated with two doses of MuCV (2009-2013 was 114.02/100 000; 2014-2015 was 45.66/100 000) and lower than 3-5 years old vaccinated one doses of MuCV. A total of 1 785 serum samples were collected from the healthy population, the average seroprevalence was 80.62% and Geometric Mean Concentration (GMC) was 38.11 IU/ml (95%CI: 37.03-39.19 IU/ml) . There was no significant difference about seroprevalence in different regions, while the GMC in middle region was significantly higher compared to east and west region. The prevalence and GMC in children aged 19 months-2 years and 3-5 years old who received one dose of MuCV were significantly higher than those of <19 months old children. The GMC (46.88 IU/ml, 95%CI: 39.43-55.74 IU/ml) in children aged 6-9 years old who received the two doses MuCV was significantly higher than that of aged 3-5 years old children (31.71 IU/ml, 95%CI: 27.23-36.93 IU/ml). Conclusion: The incidence of mumps in Shandong was still at a high level in spite of coverage one doses MuCV to children. Compared with the period of the 1 dose MuCV immunization strategy, the incidence the groups coverage two doses MuCV was significantly reduced and lower the groups coverage one dose MuCV, but the prevalence and GMC were higher than that of the groups coverage one dose MuCV.

Static model simulation for routine mumps vaccination in Japan: with a result of mumps-related complications in a Japanese community hospital

Purpose

Mumps vaccine has not been included in the routine national immunization program in Japan, leading to low vaccine coverage rates and periodic epidemics approximately every 5 years. Our hospital (a secondary community hospital in Japan) experienced an increased number of mumps-related complications with a nationwide epidemic in 2016. Using previously reported data and mumps-related cases in our hospital, we estimated the cost-effectiveness of routine mumps vaccination in Japan with a static model using current epidemiologic data.

Materials and Methods

With a decision tree flowchart of mumps infection and adverse events, we estimated the burden of mumps-related complications in our hospital for 5 years, and calculated the current annual national burden. Finally, we compared the current burden and assumptive burden of the stable state after routine vaccination in Japan using a static model.

Results

The cost-benefit ratios with sensitivity analysis were 3.69 (1.08-9.52) and 6.84 (1.51-23.73) in independent inoculation and simultaneous inoculation, respectively, from a social perspective in addition to an annual gain of 9,487 (3,227-14,659) quality adjusted life years.

Conclusion

We contributed additional evidence in terms of cost-effectiveness that routine mumps vaccination should be introduced in Japan with simultaneous inoculation.

Resurgence of mumps in Korea

Routine vaccination against mumps has markedly reduced its incidence. However, the incidence of mumps continuously has increased since 2007. In 2013, a large mumps epidemic occurred in Korea, and this epidemic is still an ongoing problem. This epidemic occurred primarily in school settings and affected vaccinated adolescents, predominantly male students. The recent resurgence of mumps is caused by multiple factors: suboptimal effectiveness of the current mumps vaccines, use of the Rubini strain vaccine, waning immunity in the absence of natural boosting due to the marked reduction in the mumps incidence, genotype mismatch between the vaccine and circulating mumps virus strains, and environmental conditions that foster intense exposures. Containment of mumps outbreaks is challenging because the sensitivity of diagnostic tests is low among vaccinees and control measures are less efficient because of the inherent nature of the mumps virus. Despite the suboptimal vaccine effectiveness in outbreak settings, maintaining the high vaccine coverage is an important strategy to prevent mumps outbreaks, given that the routine use of mumps vaccines has substantially reduced the incidence of mumps and its complications as compared with that in the pre-vaccine era. In order to control the current mumps epidemic and prevent further outbreaks, we need to better understand the dynamics of mumps among vaccinated populations and the changing epidemiology in Korea. Concerted efforts should be made to systematically monitor the immunization status of the Korean population and to improve diagnosis efficiency. Furthermore, more effective mumps vaccines need to be developed in the future.

Factors that affect voluntary vaccination of children in Japan

Some important vaccinations are not included in the routine childhood immunization schedule in Japan. Voluntary vaccinations are usually paid as an out-of-pocket expense. Low voluntary vaccination coverage rates and high target disease incidence are assumed to be a consequence of voluntary vaccination. Therefore, this study aimed to explore factors associated with voluntary vaccination patterns in children. We conducted an online survey of 1243 mothers from a registered survey panel who had at least one child 2 months to <3 years of age. The voluntary vaccination mainly correlated positively with annual household income and mothers' positive opinions about voluntary vaccinations, but negatively with number of children. Financial support, especially for low income households and households with more than one child, may motivate parents to vaccinate their children. Communication is also an important issue. More opportunities for education and information about voluntary vaccinations should be provided to mothers without distinguishing between voluntary and routine vaccination.

[An outbreak of mumps in a high school: Estimation of vaccine effectiveness. Zaragoza 2011]

INTRODUCTION

Mumps outbreaks continue to occur, even after the consolidation of vaccination programs. An outbreak of mumps occurred in a high school in Zaragoza during December 2011.

OBJECTIVE

To describe the outbreak and estimate vaccine effectiveness.

METHODS

CASE DEFINITION

unilateral or bilateral swelling of the parotid or other salivary glands for three or more days without any other apparent cause.

REFERENCE POPULATION

People attending the 'Parque Goya' High School or with transmission chain origin in the High School.

OUTBREAK PERIOD

From two days before the onset of symptoms of the first case to five days after the last case. Samples were collected for virus confirmation (IgM, urine culture and oropharyngeal exudate), and isolates were processed for genotyping. A retrospective cohort study was performed in two high school classrooms to estimate vaccine efficacy. Public health authorities conducted active surveillance, isolation of cases, and vaccination of susceptible contacts.

RESULTS

There were 27 cases. Twenty-one (77.8%) were vaccinated with two doses of Measles-Mumps-Rubella vaccine. Twelve (44%) were confirmed microbiologically. G1 genotype was determined in six cases. According to the cohort study, vaccine efficacy for one dose was 34% (95%CI: -44 to 70), and was 67% (95%CI: 28 to 83) for two doses.

CONCLUSIONS

Vaccine effectiveness was lower than expected. Early detection and isolation of cases have been instrumental in preventing new cases in schools.

Mumps outbreak and laboratory diagnosis

BACKGROUND

Several mumps outbreaks have been reported in Europe and in the United States among highly vaccinated populations. Biological diagnosis is classically based on the detection of mumps-specific IgM, but the ability of serological tests to confirm mumps infection seems to be limited among vaccinated patients.

OBJECTIVES

We aim to report a mumps outbreak in an engineering school in Grenoble, France, from February to June 2013 and results of the biological testing.

STUDY DESIGN

WHO definitions were used to define cases. Mumps--specific IgM and IgG were assessed by a commercially available EIA. Mumps RNA detection by real time reverse transcriptase polymerase chain reaction tests (RT-PCR) and mumps genotyping were performed by the French National Reference Centre for Paramyxoviridae.

RESULTS

Sixty two mumps patient-cases were identified using WHO case definitions, 20 being biologically explored, of which 17 were confirmed by biological tests. Vaccination status was documented for 27 patients/62: 4 (14.8%) patients had received one dose of MMR vaccine, and 23 (85.2) two doses of MMR vaccine. Among the biologically explored patients, 83% had a positive RT PCR at the first sampling whereas only 45% had positive or equivocal IgM. All the genotyped strains were genotype G.

CONCLUSIONS

Mumps laboratory diagnosis in a highly vaccinated population is challenging. Serological tests among vaccinated patients should be interpreted cautiously and confirmed by RT-PCR tests at the beginning of a mumps outbreak.

Development of a simplified and convenient assay for cell-mediated immunity to the mumps virus

Because methods for measuring cell-mediated immunity (CMI) to the mumps virus are expensive, time-consuming, and technically demanding, the role of CMI in mumps virus infection remains unclear. To address this issue, we report here the development of a simplified method for measuring mumps virus-specific CMI that is suitable for use in diverse laboratory and clinical settings. A mumps vaccine was cultured with whole blood, and interferon (IFN)-γ released into the culture supernatant was measured using an enzyme-linked immunosorbent assay. IFN-γ production in blood from vaccinated subjects markedly increased in response to the vaccine and decreased before the antibody titer decreased in some cases, suggesting that this assay may be used as a simple surrogate method for measuring CMI specific for the mumps virus.