Measles vaccination in the presence of maternal antibodies primes for a balanced humoral and cellular response to revaccination

Early or low dose antigen exposure can prime the immune system for subsequent responses; the so-called "prime-boost" effect. In the context of a Sudanese measles vaccine trial, we assessed whether or not such early exposure could influence the response to revaccination. Children received either Connaught high titer vaccine (CN: n = 53; 10(4.7)pfu) or meningococcal A + C vaccine as a placebo (MEN: n = 58) at 5 months of age. At 9 months of age, all received standard titer Schwarz vaccine (SCH: 10(3.9)pfu). Neutralizing antibodies were measured before initial vaccination and at 9 months of age (plaque reduction neutralization assay (PRN)) and again at 5 years of age (syncytium inhibition assay (SIA)). Lymphoproliferative responses to measles virus (MV) antigens were evaluated at 5 years of age. Eleven of the 53 CN-SCH children (21%) had sub-protective neutralizing antibody titers prior to revaccination (log PRN 1.5 +/- 0.03 versus 2.9 +/- 0.07 in the remaining 42 children; P < 0.004). Maternal antibody titers at the time of initial vaccination in these 11 were high (PRN 2.44 +/- 0.12 versus 1.9 +/- 0.04; P < 0.0001). At 5 years of age, neutralizing antibodies were comparable in the 11 CN-SCH poor responders (log SIA 2.1 +/- 0.09), the remaining CN-SCH children (2.2 +/- 0.06) and the MEN-SCH group vaccinated only once at 9 months of age (2.25 +/- 0.06). In contrast, 7/11 of the CN-SCH poor responders (64%) had stimulation indices (SI) > 3 in response to MV antigens at 5 years of age (SI 3.1 +/- 0.6) compared with only 14% in the remaining children of the CN-SCH group (2.0 +/- 0.3; P = 0.05) and 8% in the MEN-SCH group (1.4 +/- 0.2; P < 0.0003). These data suggest that early measles vaccination in the presence of maternal antibodies can sometimes prime for a balanced humoral and cellular immune response to subsequent revaccination.     

Cell-mediated and antibody immune responses to AIK-C and Connaught monovalent measles vaccine given to 6 month old infants

Measles vaccination of infants younger than 1 year of age should be successful in populations with a high proportion of measles vaccinated mothers. Infants whose mothers were vaccinated are born with less maternal antibody which can interfere with vaccination compared with infants whose mothers had measles. AIK-C or Connaught (CLL) measles vaccine was given to 300 6 month infants born to mothers who had measles (group 1) or who were vaccinated against measles (group 2). Pre- and post-vaccination measles antibody was measured by EIA and PRN and cell mediated immunity (CMI) by blast transformation and production of interferon-gamma and interleukin-10. After vaccination, mean antibody level, seroconversion and blastogenesis were significantly lower for group 1 than group 2 (p < 0.05). Post-vaccination measles IgG was significantly higher for group 2 CLL vaccinees compared with group 2 AIK-C (p < 0.05); seroconversion rates were 73 and 63%, respectively. More than 93% of group 2 infants had elevated measles IgG after vaccination. About 89% of all children had some evidence of a blastogenic response. Lymphoproliferation correlated strongly with cytokine production and weakly with IgG. Not all seroresponders had a CMI response and vice versa. AIK-C and CLL vaccines induce strong measles specific T and B immunity in most 6 month infants of vaccinated mothers.     

Specialist vaccination advice and pockets of resistance to MMR vaccination: lessons from an outbreak of measles

An outbreak of measles was associated with a private nursery school in north west London. Sixteen cases were identified of whom 13 were laboratory confirmed. The majority of cases were aged three years or younger. Older cases were siblings of younger cases. None of the cases had been vaccinated against measles. In the nursery school 33% of the children had not received MMR vaccination. Based on specialist advice from the Health Protection Agency the outbreak control team recommended that children with no history of MMR vaccination should have a first MMR dose as soon as possible and that children with one MMR dose should receive the second dose as soon as possible (minimum of one month between doses). Some parents had strong negative views about MMR and represented 'pockets of resistance' to vaccination advice. The specialist vaccination advice, which was different to national immunisation guidelines, also caused some confusion amongst other health professionals. With a decrease in MMR vaccination uptake and resulting increased potential for future measles outbreaks, clinicians should be aware of and understand specialist vaccination advice intended to deal with outbreaks.     

Immunogenicity of aerosol measles vaccine given as the primary measles immunization to nine-month-old Mexican children

Aerosol measles vaccination has been found to be more immunogenic than subcutaneous administration as a booster in school aged children, and immunogenic in 12-month-old children as a primary dose. The objective of the study was to evaluate immunogenicity to aerosol measles vaccine in 9-month-old children. METHODS: Nine-months-old infants received Edmonston-Zagreb measles vaccine by aerosol (10(3.58) CCID50/0.1 mL, estimated retained dose 10(2.81) CCID50 or subcutaneous route (10(4.28) CCID50/0.5 mL); cellular and humoral immunity and adverse events were assessed. RESULTS: Measles-specific T cell proliferative responses developed in 42% of children given aerosolized vaccine compared with 67% of those who received subcutaneous vaccine (p = 0.01); the mean stimulation index (SI) was 4.4+/-0.7 versus 6.9+/-1, respectively, (p = 0.05). Seroconversion rates were 33 and 92% after aerosol or subcutaneous immunization (p < 0.001). Among infants who developed serologic responses, measles geometric mean titers (GMT; 95% CI) by neutralizing antibody assay were 215 mIU/mL (115-400) in aerosol vaccine recipients and 411 mIU/mL (345-490) in those given subcutaneous vaccine (p = 0.06). CONCLUSIONS: The proportion of 9-month-old infants who developed cellular and/or humoral immunity to measles was lower in the aerosol group but measles antibody and T cell responses were comparable among those who developed measles immunity. Differences in response rates are attributable to the lower aerosol dose. Improving aerosol delivery or increasing the dose may enhance immunogenicity of primary aerosol measles vaccination in this age group.     

Immunogenicity and efficacy of one dose measles-mumps-rubella (MMR) vaccine at twelve months of age as compared to monovalent measles vaccination at nine months followed by MMR revaccination at fifteen months of age

BACKGROUND AND METHODS: measles is a common cause of morbidity and mortality in developing countries. Although the measles-mumps-rubella vaccine (MMR) is currently in use in developed countries, monovalent measles vaccine (MV) is routinely recommended by World Health Organization (WHO) at 9 months of age in Turkey, as in many other developing countries. In this study, 442 Turkish children received MV at 9 months of age and were revaccinated with MMR vaccine at 15 months of age. In the second group 495 children received MMR at 12 months of age with no earlier measles vaccination. Antibodies were measured before the first vaccination and 6 weeks after the MMR. All children had been followed for occurrence of measles infection for 60 months. Two vaccination schedules were compared for immunogenicity and protection rates. CONCLUSIONS: seroconversion and clinical protection rates were significantly higher in children who received only MMR at 12 months of age than in children revaccinated at 15 months of age. Seroconversion rate for measles was 69.9% in children who received MMR at 12 months of age and 90.3% in children revaccinated at 15 months of age (P=0.0003). While there was no measles case in children who were revaccinated, 12 (2.7%) children in the first group acquired measles during the follow-up period. Vaccination at 12 months of age appeared to be better than the current national standard. The late elimination of maternal antibodies and the inhibitory effect of a weak antibody response after the first dose of vaccine at 9 months may explain the better immunogenicity and efficacy of the MMR vaccine given at 12 months of age.     

Antibodies to measles,mumps, and rubella virus in Thai children after two-dose vaccination at 9 months and 2.5 years: A longitudinal study

IntroductionThailand changed the schedule of childhood measles–mumps–rubella (MMR) vaccination in 2014, moving the second dose from the age of 6 years to 2.5 years. There are currently no data on antibody responses to the MMR vaccine since this recommendation.Material and methodsWe investigated antibody responses in a cohort of children who received two doses of MMR vaccine at the ages of 9 months and 2.5 years that was originally established to evaluate antibody levels to Bordetella pertussis antigens (ClinicalTrials.gov no. NCT02408926). Infants were born to mothers who previously received tetanus–diphtheria–acellular pertussis vaccine at 27–36 weeks of gestation. Anti-measles, -mumps, and -rubella virus IgG levels were measured at birth (cord blood) and the ages of 2 and 7 months (before the first MMR vaccination); 18 and 24 months (9 and 15 months, respectively, after the first dose); and 36 months (6 months after the second dose) using commercially available enzyme-linked immunosorbent assay kits.ResultsAt 7 months of age, 96.2%, 99.6%, and 98.8% of infants had no protection against measles, mumps, and rubella, respectively. Levels of antibody against all three antigens increased significantly after the first but not the second dose. At 6 months after two-dose vaccination, 97.4%, 84.8%, and 78.7% of children remained seroprotected against measles, mumps, and rubella, respectively.ConclusionsMaternally derived antibodies to measles, mumps, and rubella virus disappeared by the age of 7 months in Thai children. Two-dose MMR vaccination at 9 months and 2.5 years of age induced robust immune responses against these viruses.     

Antibody persistence in children aged 6–7 years one year following booster immunization with two MMR vaccines applied by aerosol or by injection

ImportanceIn a previous study on booster vaccination, we reported that two aerosolized MMR vaccines were as safe and immunogenic as injectable vaccines containing the same antigens. We now present results of antibody persistence one year after immunization.ObjectiveTo assess the antibody persistence for measles, mumps, and rubella one year following booster immunization.MethodsWe performed clinical and serological follow-up of participants in a previous study of Mexican children aged 6–7 years, in which participants were randomized to four groups receiving, by aerosolized or by injection, the MMR SII vaccine (Serum Institute of India), or the MMR II (Merck Sharp & Dhome). We evaluated the antibody persistence by PRN test for measles and by ELISA for rubella and mumps. The occurrence of clinical events was evaluated via periodic visits of a nurse team to children’s schools and homes.ResultsOf the 260 initial participants, 241 completed one-year follow-up. There were only statistically significant differences in baseline seropositivity for mumps. One year after immunization, seropositivity in all groups was 100% for measles and rubella. The seropositivity rank for mumps was from 90.3% for the injected vaccine MMR II to 96.6% for vaccine MMR SII applied by aerosol; these differences were not statistically significant. With exception of the aerosolized vaccine MMR SII for the geometric mean titer (GMT) for measles, all study groups presented declination of GMT for the three viruses. The difference between the aerosolized vaccines MMR SII and MMR RII was statistically significant for mumps antibodies. Only mild clinical events were identified.ConclusionUnder conditions of no endemic transmission for measles and rubella, and of low circulation of mumps virus, school-aged children remained seropositive to the three viruses one year following booster immunization.The study was registered under CMN 2010-005 number at COFEPRIS (National Regulatory Authority).     

Seroprevalence of Antibodies to Measles, Mumps, and Rubella among Thai Population: Evaluation of Measles/MMR Immunization Programme

Stored serum specimens, from four regions of Thailand, of healthy children attending well baby clinics and of healthy people with acute illnesses visiting outpatient clinics were randomly sampled and tested for IgG antibody to measles, mumps, and rubella (MMR). The immunity patterns of rubella and mumps fitted well with the history of rubella and MMR vaccination, seroprotective rates being over 85% among those aged over seven years. A high proportion of younger children acquired the infection before the age of vaccination. MMR vaccination should preferably be given to children at an earlier age. For measles, 73% seroprotective rates among children, aged 8-14 years, who should have received two doses of measles/MMR vaccine, were lower than expected. This finding was consistent with the age-group reported in outbreaks of measles in Thailand. The apparent ineffectiveness (in relation to measles) of MMR immunization of 1^st grade students warrants further studies.Key words: Antibodies, Immunization, Measles, Measles vaccine, Mumps, MMR vaccine, Rubella, Seroepidemiologic studies, Seroprevalence, Vaccination, Thailand     

Kinetics of antibody and memory B cell responses after MMR immunization in children and young adults

The persistence of antigen-specific memory B-cells (MBCs) in children and young adults long time after vaccination against measles, mumps and rubella (MMR) is not known. Here we have looked at the Swedish immunization program and examined children 1–10 years after the first MMR dose in early childhood, as well as young adults 7–18 years after the second dose of MMR. We show that Ab titers and MBCs against measles and rubella have different kinetics, indicating that the MBC pool and the corresponding Ab titers are regulated independently. These data fit well with other findings that continuous IgG secretion comes from long-lived plasma cells and not MBCs. We also demonstrate that individuals with low post-vaccination Ab titers might have an adequate MBC response. It remains to be shown if memory B-cells provide the same protection as specific antibodies, but our data is a valuable complement to the incomplete knowledge about correlates of protection after vaccination.     

Immune response to measles vaccine in Peruvian children.

OBJECTIVE: To evaluate the immune response in Peruvian children following measles vaccination. METHODS: Fifty-five Peruvian children received Schwarz measles vaccine (about 10(3) plaque forming units) at about 9 months of age. Blood samples were taken before vaccination, then twice after vaccination: one sample at between 1 and 4 weeks after vaccination and the final sample 3 months post vaccination for evaluation of immune cell phenotype and lymphoproliferative responses to measles and non-measles antigens. Measles-specific antibodies were measured by plaque reduction neutralization. FINDINGS: The humoral response developed rapidly after vaccination; only 4 of the 55 children (7%) had plaque reduction neutralization titres <200 mlU/ml 3 months after vaccination. However, only 8 out of 35 children tested (23%) had lymphoproliferative responses to measles antigens 3-4 weeks after vaccination. Children with poor lymphoproliferative responses to measles antigens had readily detectable lymphoproliferative responses to other antigens. Flow cytometric analysis of peripheral blood mononuclear cells revealed diffuse immune system activation at the time of vaccination in most children. The capacity to mount a lymphoproliferative response to measles antigens was associated with expression of CD45RO on CD4+ T-cells. CONCLUSION: The 55 Peruvian children had excellent antibody responses after measles vaccination, but only 23% (8 out of 35) generated detectable lymphoproliferative responses to measles antigens (compared with 55-67% in children in the industrialized world). This difference may contribute to the less than uniform success of measles vaccination programmes in the developing world.     

The effect of measles-mumps-rubella (MMR) immunization on the immune responses of previously immunized primary school children

Current policies for measles control call for administration of a second dose of vaccine to immunize those who failed to respond to the initial dose and to boost the responses of those with low levels of antibody. However, there has been concern expressed publicly that reimmunization may have adverse immunologic consequences. To determine the effects of reimmunization on immune responses, primary school children (N=38, mean age=6.14+/-0.35 years) with documented previous measles-mumps-rubella vaccine (MMR) immunization during infancy 4-5 years earlier were studied before and 1 month after receiving MMR as a part of routine reimmunization in Beer-Sheva, Israel. A substantial number of children were seronegative to measles (24%), mumps (34%) and rubella (44%). On reimmunization all seroconverted to mumps and rubella and all but one (92%) seroconverted to measles. The geometric mean titer of measles virus neutralizing antibody increased from 171 to 724 and the greatest increases occurred in those with the lowest pre-immunization titers. Moderate increases in levels of total IgM, IgG and IgE were detected in those with increases in antibody to measles virus. After reimmunization leukocyte counts decreased significantly from (5.8 x 10(6))+/-2.3 to (3.4 x 10(6))+/-0.7 ml(-1) (P=0.0001). The percentages of both CD4(+) and CD8(+) T cells decreased while the CD4:CD8 ratio remained unchanged. The percentage of CD56(+) natural killer (NK) cells increased from 5.2+/-2.7 to 7.2+/-2.8 (P=0.01). Functional assays showed improved lymphoproliferation in response to stimulation with phytohemagglutinin and tetanus toxoid and stable NK lytic activity. Therefore, reimmunization was accompanied by decreased leukocyte counts, but leukocyte function was unchanged or improved.     

A randomised single blind trial of a combined mumps measles rubella vaccine to evaluate serological response and reactions in the UK population

Four hundred and twenty children were randomly assigned to receive either mumps measles rubella (MMR) vaccine (207) or measles vaccine (213) in a single blind study, to investigate the reactogenicity and serology of the MMR vaccine. There was no significant difference between the number of children developing symptoms after MMR vaccination to those developing symptoms after measles vaccination. Both vaccines are associated with a rash, temperature and restlessness five to thirteen days after vaccination. The serological response to measles vaccine was similar in both groups with 92-6% seroconverting with MMR, and 96-8% with measles. Seroconvertion against mumps and rubella with the MMR vaccine was 88% and 96% respectively. This study confirms the safety and efficacy of the MMR vaccine in a UK population.     

上海市麻疹、流行性腮腺炎、风疹抗体水平调查分析

[目的 ]　了解本市健康人群麻疹、腮腺炎、风疹的抗体水平。　 [方法 ]　采集 0～ 5 0岁健康人群血标本 5 43份 ,检测麻疹、腮腺炎、风疹抗体。　 [结果 ]　小于 8月龄组麻疹抗体GMT最低 ,接种麻疹疫苗后抗体GMT显著升高 (P<0 .0 0 1) ;小于 8月龄组及 8月龄组风疹抗体水平最低 ,1岁接种疫苗后风疹抗体显著升高 (P <0 .0 0 1) ,但随着年龄的增长抗体水平有所下降 ,抗体阳性率维持在 85 %以上 ;小于 8月龄组及 8月龄组流行性腮腺炎抗体水平最低 ,1岁以上各年龄组抗体水平显著上升 (P <0 .0 0 1)。　 [结论 ]　上海市现阶段实行麻疹疫苗、MMR疫苗的接种程序比较合理和有效 ,但应该进一步开展上海市育龄期妇女风疹抗体水平调查和MMR疫苗免疫持久性观察 ,研究预防未及龄儿童麻疹疫苗免疫策略、育龄期妇女接种风疹疫苗免疫策略 ,预防先天性风疹综合征     

Assessment of the potency and potential immunomodulatory effects of the measles mumps rubella and varicella vaccine in infants

This study compared the potency and immunomodulatory effects of measles mumps rubella (MMR) vaccine given to infants alone or in combination with varicella (MMR and V). In an additional group, MMR vaccination was delayed 42 days to permit analysis of potential effects on underlying maturation of systemic immune functions. Assessment of immunity to the vaccines indicated consistent antibody production coupled with mixed Th1/Th2 memory, and no significant differences between vaccine groups or to the group who had their MMR vaccination delayed. Parallel analyses of cytokine responses to phytohaemagglutinin and tetanus toxoid did not detect any "bystander" effects of the vaccines on systemic immunity.     

4~6岁儿童接种麻疹-流行性腮腺炎-风疹联合减毒活疫苗加强免疫的免疫原性与安全性研究

目的 探讨4~6岁儿童接种麻疹-流行性腮腺炎-风疹联合减毒活疫苗（MMR）后的加强免疫原性与安全性。方法 分别在山西省、内蒙古自治区以及北京市招募曾有8月龄和18月龄接种过1剂麻疹-风疹联合减毒活疫苗和MMR疫苗免疫史的4~6岁儿童作为研究对象,分为4、5、6岁组,进行MMR疫苗加强免疫研究。接种MMR疫苗前与接种后35~42 d各采集血标本3 ml。在研究期间,主动监测疫苗接种后30 min、1 d、2 d、3 d、4~12 d,以及13~42 d的不良事件。血清采用酶标法检测麻疹、流行性腮腺炎和风疹的IgG抗体。采用方差分析或非参数检验比较研究组间麻疹、腮腺炎和风疹抗体几何平均浓度（GMC）,采用χ²检验或Fisher确切概率法比较组间阳性率和不良事件发生率。结果 共500名完成免后采血儿童纳入免疫原性分析,535名儿童纳入安全性分析。总体不良事件发生率为20.37%,轻度不良事件最多。局部与全身不良事件发生率分别为0.37%和20.00%。局部不良事件的症状以接种部位发红为主,全身不良事件以发热症状为主,其次为咳嗽、皮疹、流涕等。在4~6岁进行1剂MMR疫苗加强免疫后,麻疹抗体、腮腺炎抗体与风疹抗体阳性率均在99%以上,3组间阳性率差异无统计学意义。3组间仅腮腺炎抗体GMC差异有统计学意义（P=0.042）,麻疹与风疹抗体相关结果均无差异。免前阴性者的麻疹、腮腺炎及风疹抗体GMC均低于免前阳性者。结论 在4~6岁儿童中进行MMR疫苗的加强免疫,具有良好的免疫原性与安全性,在4~6岁之间的加强免疫效果相近。     

Seroprevalence of measles, mumps and rubella antibodies in Luxembourg: results from a national cross-sectional study

A serological prevalence survey was carried out in Luxembourg during 2000-2001 to determine the antibody status of the Luxembourg population against vaccine-preventable infections. Blood samples of children and adolescents were collected prospectively in randomly selected schools. Samples of adults were obtained through volunteer patients of the national health laboratory or of the mandatory pre-nuptial test. Measles, mumps and rubella (MMR) virus antibody concentrations were measured using commercial ELISA tests. Age-standardized prevalence of measles, mumps and rubella virus antibodies was found to be 96.58, 75.40 and 95.69% respectively. Significant age-dependence of serology was observed for all three infections, with study participants born after the introduction of the MMR vaccine experiencing a gradual decline of antibodies following vaccination in childhood. Older study participants who were more likely to have antibodies from natural infection had consistently higher titres than younger individuals. Present vaccination coverage with MMR appears to be sufficient to prevent large local outbreaks of measles and rubella, but probably not mumps.     

A comparison of booster immunisation with a combination DTPa-IPV vaccine or DTPa plus IPV in separate injections when co-administered with MMR, at age 4-6 years

This study evaluated GSK's combined DTPa-IPV vaccine (Infanrix-IPV) given as a fifth consecutive acellular pertussis booster dose in conjunction with the second dose of MMR vaccine (Priorix) in children aged 4-6 years. The immunogenicity and reactogenicity of this vaccine regimen was compared with separate injections of DTPa and IPV when given concomitantly with MMR. A cohort of 362 children previously primed with four doses of DTPa and OPV, and a single dose of MMR were randomized to receive either DTPa-IPV+MMR (N=181) or DTPa+IPV+MMR (N=181). Antibody concentrations were measured prior to and 1 month after the booster dose. After immunisation all subjects from both groups had seroprotective antibody levels against diphtheria, tetanus and the three poliovirus serotypes, > or = 96% showed vaccine response to PT, FHA and PRN, all were seropositive to mumps and rubella, and all but one subject were seropositive to measles. Immunogenicity results for each component antigen were similar for DTPa-IPV and separately co-administered DTPa and IPV. Local reactions were common with 24.0% and 31.1% of children experiencing swelling >50mm at the DTPa-IPV and DTPa injection sites, respectively. The DTPa-IPV combination did not increase the incidence or intensity of adverse events compared with separately administered DTPa+IPV. The response to the concomitantly administered MMR vaccine was similar in the two groups and similar to previously reported responses for a second dose of MMR. This combined DTPa-IPV vaccine has a similar reactogenicity profile to DTPa, is immunogenic when given as a booster dose at 4-6 years of age, and has no impact on the immunogenicity of a co-administered second dose of MMR vaccine.     

Measles vaccination coverage among five-year-old children: implications for disease elimination in Australia

OBJECTIVES: To (i) assess under-reporting of measles-mumps-rubella (MMR) vaccinations to the Australian Childhood Immunisation Register (ACIR); (ii) estimate MMR coverage among five-year-old children and the proportion immune to measles infection; (iii) identify factors related to non-uptake of MMR vaccination. METHODS: We analysed ACIR data for a birth cohort of approximately 64,000 children aged five years. The parents of a sample of 506 children with no ACIR record for the second MMR vaccination (MMR2), due at four years of age, were interviewed by telephone to assess under-reporting to the ACIR and reasons for non-uptake of MMR vaccination. RESULTS: Parents reported that 22% (n = 111) of the surveyed 506 children had received MMR2 before their fifth birthday, and 42% (n = 214) by approximately 5.5 years of age. After correcting for this level of under-reporting to the ACIR, MMR2 coverage for the entire cohort at five years of age was 52.9% (95% CI 52.3-53.4), and increased to 84.1% (95% CI 83.4-84.8) by approximately 5.5 years of age. This was 4.3% and 8.2%, respectively, higher than ACIR coverage estimates at the two ages. Based on the corrected MMR coverage estimates, 93% of the cohort was immune to measles due to vaccination. The most common parent-reported reason for incomplete vaccination was lack of knowledge about the MMR vaccination schedule. CONCLUSIONS: Measles elimination in Australia will require continued effort in vaccination coverage and timeliness among pre-school children. School-entry requirements are important for MMR2 uptake. Strategies are needed to improve reporting to the ACIR for more accurate measurement of coverage.     

Booster immune response in children 6–7 years of age,randomly assigned to four groups with two MMR vaccines applied by aerosol or by injection

Importance

Aerosol immunization may be a useful tool to reach and sustain the elimination of measles, rubella, and congenital rubella syndrome. We compared booster seroresponses to aerosolized or injected MMR vaccines containing different strains of measles (Attenuvax or Edmonston–Zagreb) and mumps (Jeryl–Lynn or Leningrad–Zagreb).

Objective

To assess the safety and immunogenicity of two MMR: Vaccines administered by aerosol.

Methods

A randomized and controlled clinical trial was conducted to evaluate the safety and booster responses to the MMR SII (Serum Institute of India) and MMR II (Merck Sharp & Dhome) vaccines, both of which were administered by aerosol (ae) or injection (inj) to Mexican children aged 6–7 years in elementary schools. The seroresponses were evaluated by PRN (measles) and ELISA (rubella and mumps). Adverse events were followed-up for 28 days after the immunization.

Results

Two hundred and fifty-three of 260 children completed the one-month follow-up. All participants reached protective seropositivity for measles and rubella after immunization, and 98.3 to 100% reached protective seropositivity for mumps (p = 0.552). The proportions of the seroresponses (a 2-fold rise from the baseline antibody titers) to measles were 38.3% for MMR SII (ae), 31.3% for MMR II (ae), 37.5% for MMR SII (inj), and 44.6% for MMR II (inj) (p = 0.483). The seroresponses for rubella were 26.7% for MMR SII (ae), 31.3% for MMR II (ae), 46.9% for MMR SII (inj), and 40.0% for MMR II (inj) (p = 0.086). The seroresponse to mumps were 31.7% for MMR SII (ae), 25.0% for MMR II (ae), 48.4% for MMR SII (inj), and 53.9% for MMR II (inj) (p = 0.002). The difference in the seroresponse of a 4-fold rise from the baseline antibody titers was not statistically significant. Only mild adverse events were noted.

Conclusion

Aerosolized vaccines were as safe and as immunogenic as injected vaccines.

Protocol registration

CMN 2010-005 (National Regulatory Authority).     

An evaluation of measles, mumps and rubella vaccine in a population of Yorkshire infants

In October 1988 combined measles, mumps and rubella (MMR) vaccination replaced monocomponent measles as part of the routine childhood vaccination programme in the United Kingdom. Prior to this policy change a study was undertaken in 335 children aged 15 months, to evaluate the clinical reactions and immunogenicity of the new combined MMR vaccine (Trimovax, Immravax, Merieux), in comparison with an established monocomponent measles vaccine (Rouvax, Merieux). Parents were asked to select whether their child should receive MMR vaccine or measles monocomponent; over 95% chose MMR. Children who were given the MMR vaccine had seroconversion rates of 96% for measles, 97% for mumps and 100% for rubella, whilst those who received monocomponent measles vaccine had a seroconversion rate of 100%. The number of side effects reported was similar with both vaccines; all were mild and self-limiting. The results from this study confirm the efficacy and low reactogenicity of MMR vaccine and support its use as part of the routine childhood immunisation programme in the United Kingdom.