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.     

Changes of the immunological patterns against measles, mumps and rubella. A vaccination programme studied 3 to 7 years after the introduction of a two-dose schedule

A two-dose vaccination programme using a combined measles, mumps and rubella vaccine (MMR) and administration at the ages of 18 months and 12 years was introduced in 1982. The 12-year-old schoolchildren were tested yearly from 1985 to 1989 on serum samples obtained prior to and after vaccination. Each year between 420 and 756 children were tested. The method used for antibody testing was the haemolysis-in-gel (HIG) assay. For measles also the enzyme-linked immunosorbent assay (ELISA) and the neutralization titre (NT) were applied. Only minor variations of the prevaccination immunity to measles were seen during the period 3-7 years after introduction of the programme. The age groups studied had partly been vaccinated against measles earlier. Between 12 and 16% lacked prevaccination immunity. In contrast the immunity to mumps and rubella of the 12-year-old children decreased considerably during the study period. No general vaccination against these diseases had been performed. Thus the susceptibility to mumps increased from 14% in 1985 to 39% in 1989 and to rubella from 41 to 57%. The seroconversion rate of children seronegative for measles was high, i.e. 100% in 1985 and later varied between 96 and 97%. For mumps, the seroconversion rate was lower and varied between 72 and 88%. All sera converted to rubella. During the follow-up period there was a declining incidence of measles, mumps and rubella. The relationship between the vaccination and reduction of disease and natural immunity strongly suggests that the association is causal and that this vaccination policy reduced the transmission of infection.     

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 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     

Mutual interference on the immune response to yellow fever vaccine and a combined vaccine against measles, mumps and rubella

A randomized trial was conducted to assess the immunogenicity and reactogenicity of yellow fever vaccines (YFV) given either simultaneously in separate injections, or 30 days or more after a combined measles-mumps-rubella (MMR) vaccine. Volunteers were also randomized to YFV produced from 17DD and WHO-17D-213 substrains. The study group comprised 1769 healthy 12-month-old children brought to health care centers in Brasilia for routine vaccination. The reactogenicity was of the type and frequency expected for the vaccines and no severe adverse event was associated to either vaccine. Seroconversion and seropositivity 30 days or more after vaccination against yellow fever was similar across groups defined by YFV substrain. Subjects injected YFV and MMR simultaneously had lower seroconversion rates - 90% for rubella, 70% for yellow fever and 61% for mumps - compared with those vaccinated 30 days apart - 97% for rubella, 87% for yellow fever and 71% for mumps. Seroconversion rates for measles were higher than 98% in both comparison groups. Geometric mean titers for rubella and for yellow fever were approximately three times higher among those who got the vaccines 30 days apart. For measles and mumps antibodies GMTs were similar across groups. MMR's interference in immune response of YFV and YFV's interference in immune response of rubella and mumps components of MMR had never been reported before but are consistent with previous observations from other live vaccines. These results may affect the recommendations regarding primary vaccination with yellow fever vaccine and MMR.     

冻干麻疹-腮腺炎-风疹三联活疫苗免疫安全性及免疫学效果观察

目的 观察卫生部北京生物制品研究所研制的麻疹-腮腺炎-风疹（北京MMR）疫苗的免疫学效果。方法 分别选择10-12岁，2-2.5岁和8-12月龄儿童，接种北京MMR（实验疫苗），并与进口MMR疫苗，麻疹疫苗，腮腺炎疫苗和风疹疫苗（对照疫苗）相比较，开展该疫苗的免疫安全性和免疫原性观察研究。结果 在32名2岁以上较大龄儿童接种北京MMR疫苗无副反应发生后，对104名8-12月龄婴儿接种该疫苗，仅有6.7%和1.9%的儿童分别发生一过性发热（中低反应）和皮疹，无其他不良反应发生，北京MMR疫苗免疫接种后，其麻疹，风疹，腮腺炎HI抗体阳转率分别为100%，100%和85.7%;GMT分别为41，320和6.1，分别与对照疫苗相比，差异多无显著性。结论 北京MMR疫苗具有与目前使用的麻疹疫苗，腮腺炎疫苗，风疹疫苗及进口MMR疫苗相同的免疫安全性和免疫原性，且可以作为麻疹的基础免疫和复种疫苗使用。     

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.     

Persistence of antibodies in 4-8 year old Austrian children after vaccination with hexavalent DTaP-HBV-IPV/Hib and MMR vaccines

To determine the proficiency of the Austrian childhood vaccination schedule to induce long lasting seroprotection against vaccine preventable diseases a seroepidemiological study in 348 children between four and eight years of age was conducted. Antibodies against diphtheria, tetanus, pertussis, hepatitis B, measles, mumps and rubella antigens were assessed in children, who had been vaccinated with hexavalent DTaP-HBV-IPV/Hib vaccines at three, four, five months and in the second year of life and/or MMR vaccines in the second year of life at least once, but mostly twice.High seroprotection rates (SPRs) were detected for tetanus (96%) and measles (90%). SPRs regarding diphtheria and mumps were 81% and 72%, respectively. Rubella-SPRs were 68% in females and 58% in males. Hepatitis B-antibody levels ≥10 mIU/mL were present in 52%; antibodies against pertussis were detected in 27% of the children. SPRs for measles and rubella depended on the interval since last vaccination; mumps-antibodies were significantly lower after one MMR-vaccination only. Antibodies against diphtheria, tetanus and pertussis depended on the interval since last vaccination while HBs-antibodies did not. The low levels of antibodies 1-7 years after vaccination against pertussis, rubella and mumps after only one vaccination should be considered when recommending new vaccination schedules.     

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).     

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     

麻疹-流行性腮腺炎-风疹联合减毒活疫苗流行性腮腺炎组份免疫效果观察

目的对麻疹-流行性腮腺炎（流腮）-风疹联合减毒活疫苗（Measles,Mumps and Rubella Combined Atteruated Live Vaccine,MMR）中,流腮组份的免疫效果进行观察评价。方法对接种MMR后,流腮组份免疫学效果进行分析评价,并追踪观察记录2年内受种人群及本地人群中流腮发病情况。结果接种MMR前,流腮抗体几何平均滴度（Geometric Mean Titer,GMT）为1∶6.87,免疫后GMT为1∶26.35,免疫后GMT是免疫前GMT的3.8倍,免疫前、后GMT差异有统计学意义（Z=-6.22,P〈0.001）。免疫前、后流腮抗体阳性率分别为64.63%、95.12%,差异有统计学意义（χ2=23.71,P〈0.001）。免疫前、后流腮抗体阴性者与阳性者GMT和免疫前相比差异均有统计学意义（Z=-4.40,P〈0.001;Z=-4.84,P〈0.001）。免疫前流腮抗体阴性者与阳性者接种MMR后,免疫成功率分别为86.21%、54.72%,差异有统计学意义（χ2=8.266,P=0.004）。对受种人群及本地人群进行为期2年的流腮发病追踪观察,在受种人群中未发现流腮病例报告。结论在3-6岁儿童中接种MMR,对于预防流腮效果良好,产生的保护效果至少能维持2年。     

国产麻疹流行性腮腺炎风疹联合疫苗初免效果及免疫程序探讨

目的为观察麻疹、流行性腮腺炎(腮腺炎)、风疹联合疫苗(MMR疫苗)的安全性和免疫原性,并探讨其免疫程序.方法选择91名8月龄儿童,接种MMR疫苗,观察接种后局部反应和全身反应,并检测接种后6周血清麻疹、腮腺炎、风疹抗体阳转率和几何平均滴度(GMT).结果91名8月龄儿童接种MMR疫苗后,有8名儿童发生一过性发热,2名儿童发生皮疹,2名儿童发生局部弱反应.麻疹、风疹、腮腺炎血凝抑制(HI)抗体阳转率分别为98.61%、100.00%、74.07%,GMT分别为145.25、1248.71、14.29.结论MMR疫苗对8月龄儿童接种具有较好的安全性和免疫原性,将其初免月龄定为8月龄儿童是可行的.     

Immunogenicity of second dose measles-mumps-rubella (MMR) vaccine and implications for serosurveillance.

Measles and mumps, but not rubella, outbreaks have been reported amongst populations highly vaccinated with a single dose of measles-mumps-rubella (MMR) vaccine. Repeated experience has shown that a two-dose regime of measles vaccine is required to eliminate measles. This paper reports the effect of the first and second MMR doses on specific antibody levels in a variety of populations.2-4 years after receiving a first dose of MMR vaccine at age 12-18 months, it was found that a large proportion of pre-school children had measles (19.5%) and mumps (23.4%) IgG antibody below the putative level of protection. Only a small proportion (4.6%) had rubella antibody below the putative protective level. A total of 41% had negative or equivocal levels to one or more antigens. The proportion measles antibody negative (but not rubella or mumps) was significantly higher in children vaccinated at 12 months of age than at 13-17 months. There was no evidence for correlation of seropositivity to each antigen, other than that produced by a small excess of children (1%) negative to all three antigens. After a second dose of MMR, the proportion negative to one or more antigens dropped to <4%. Examination of national serosurveillance data, found that following an MR vaccine campaign in cohorts that previously received MMR, both measles and rubella antibody levels were initially boosted but declined to pre-vaccination levels within 3 years.Our study supports the policy of administering a second dose of MMR vaccine to all children. However, continued monitoring of long-term population protection will be required and this study suggests that in highly vaccinated populations, total measles (and rubella) IgG antibody levels may not be an accurate reflection of protection. Further studies including qualitative measures, such as avidity, in different populations are merited and may contribute to the understanding of MMR population protection.     

The immunogenicity and reactogenicity of the trivalent vaccine, Trimovax, indicated for prevention of measles, mumps, and rubella, in 12-month-old children in Belarus

In the Republic of Belarus, immunization of children against measles and mumps had been carried out using monovalent preparations according to the national schedule of measles vaccination at 12 months of age and mumps vaccination at 24 months of age. A rise of rubella incidence in the last few years (i.e., for the official registration period 1980 to 1998, there was an increase from 72.2 to 607.5 cases per 100,000 population) made it necessary to implement immunization against this infection, as well. Therefore, in 1996, combined vaccination against measles, mumps, and rubella of 12-month-old children was carried out for the first time in a clinical trial that used the vaccine Trimovax [Aventis Pasteur (formerly, Pasteur Mérieux Connaught), Lyon, France]. The reactogenicity of the vaccine was investigated in 372 children. Post-vaccination reactions were noted in 5.6% of children; in 1.3% of children the reactions were classified as severe [i.e. associated with body (axillary) temperature > or = 38.6 degrees C]. For the evaluation of immunogenicity, sera from 324 children were obtained 2 to 2.5 months after inoculation, and serum antibody levels were measured by enzyme immunoassays. Among the vaccines, protective antibody titers (expressed in inverse of dilution units) were observed to measles (> or = 1:50) in 97.8%, to mumps (> or = 1:50) in 93.8%, and to rubella (> or = 1:100) in 96.0% of children. Antibodies to all three components of the vaccine were mainly present in intermediate (1:200-1:800) or high (> or = 1:1600) titers: to measles in 96.3%; to mumps in 75.8%; and to rubella in 73.5% of vaccines. The results of these trials are evidence of the good safety and immunogenicity of this MMR vaccine, which provides an alternative to the currently used measles and mumps monovaccines, with the additional benefit of providing immunity against rubella, as well.     

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.     

Parental attitudes and decisions regarding MMR vaccination during an outbreak of measles among an undervaccinated Somali community in Minnesota

Incidence of measles is increasing in the US, largely due to transmission among growing unvaccinated communities. To elucidate predictors of parental decision to obtain measles, mumps, and rubella (MMR) vaccine for unvaccinated children during a measles outbreak, we surveyed families among a vaccine-hesitant Somali community in Minnesota. The survey assessed attitudes and beliefs about MMR vaccine, motivators for vaccinating, and intention to vaccinate future children on time. Among 300 families surveyed, 95% vaccinated their child with MMR due to fear of measles. The predominating parental concern about MMR vaccine (71%) was a fallacious presumed connection between vaccination and autism. Only 41% of parents intended to vaccinate future children on time with MMR; parents who received recommendations for MMR vaccination from multiple sources were more likely than other parents to intend to do so. These findings support the importance of diverse outreach efforts to increase vaccine coverage among undervaccinated communities.     

Duration of the immune response to MMR vaccine in children of two age-different groups

A combined vaccine against measles, mumps and rubella (MMR) was administered to both a group of children aged 10–12 months simultaneously with booster doses of compulsory diphtheriatetanus toxoids and oral poliovirus vaccine and a group of children aged 15–24 months who had previously received booster doses of the compulsory vaccines.Apart from one subject belonging to the second group who was non responder and one from the same group who did not seroconvert against the mumps virus alone, 5 to 6 weeks after MMR vaccine administration we found protective levels of antibodies against measles, mumps and rubella viruses in all children. The follow up of both groups at 3 years did not reveal difference between the two groups. Protective levels of serum antibodies against measles and mumps were found in the two groups, altough a significant decline of rubella antibodies was shown (p < 0.05).Since the immunogenicity of the vaccines in the two groups did not differ, we recommend that the scientific community reconsider the vaccination schedule until now recommended. In our opinion the MMR vaccine should be administered simultaneously with booster doses of diphtheria-tetanus toxoids and oral poliovirus vaccine at 10–12 months of age because this policy improves parents' compliance, markedly reduces community costs and simplifies routine immunization schedule.     

Seroprevalence of measles,mumps and rubella among children in American Samoa, 2011, and progress towards West Pacific Region goals of elimination

Introduction

In line with the global goals for measles elimination, countries in the West Pacific Region (WPR) have set a goal to eliminate measles by 2012. Due to its contagiousness, high population immunity is needed for achieving and documenting measles elimination. We assessed population immunity to measles, mumps and rubella among first grade children in American Samoa (AS) through a seroprevalance study.

Methods

Using commercial indirect enzyme-linked immunosorbant IgG assays (Wampole Laboratories, Cranbury, NJ) we determined IgG antibodies against the measles, mumps, and rubella (MMR) viruses in sera collected from first grade students in AS in April–May 2011. Vaccination status was retrieved from the immunization cards. Factors associated with seropositivity of measles, mumps, and rubella were analyzed separately.

Result

Among 509 first grade students, measles, mumps, and rubella seroprevalence were 92%, 90%, and 93%, respectively. The proportions of first grade students with documented one or two doses of MMR vaccine were 93% and 84%, respectively. The vaccination status of 6% of the first graders was unknown and 1% was unvaccinated. Receiving two-doses of MMR vaccines was associated with high measles and mumps seropositivity (p < 0.01).

Conclusion

The high measles seroprevalence among children shows the progress by American Samoa towards measles elimination. Achieving and maintaining high two-dose MMR vaccine coverage in all age groups will aid in attaining the measles elimination status and prevent transmission of measles from potential imported measles cases from other countries.     

Update: recommendations from the Advisory Committee on Immunization Practices (ACIP) regarding administration of combination MMRV vaccine

On February 27, 2008, new information was presented to the Advisory Committee on Immunization Practices (ACIP) regarding the risk for febrile seizures among children aged 12-23 months after administration of the combination measles, mumps, rubella, and varicella (MMRV) vaccine (ProQuad, Merck & Co., Inc., Whitehouse Station, New Jersey). This report summarizes current knowledge regarding the risk for febrile seizures after MMRV vaccination and presents updated ACIP recommendations that were issued after presentation of the new information. These updated recommendations remove ACIP's previous preference for administering combination MMRV vaccine over separate injections of equivalent component vaccines (i.e., measles, mumps, and rubella [MMR] vaccine and varicella vaccine).     

Outbreak of measles in medical students and determination of immune status to measles-mumps-rubella viruses

We conducted an investigation after a measles outbreak in medical students to determine the immunity of the medical students, the correlation between history and seropositivity, and measles-mumps-rubella vaccine effectiveness. After a preliminary study done during measles outbreak, a cross-sectional study was planned. Serum samples from 322 medical students were tested by enzyme-linked immunosorbent assay, vaccinated volunteers, then re-tested vaccinees. Histories of measles, mumps and rubella were taken. Of 322 students, seven students (2.2%) were seronegative to measles, 13 (4.0%) to mumps, and 13 (4.0%) to rubella. Historical information revealed 30.4% of sensitivity in measles and 34.3% in mumps, whereas 5.2% in rubella. Among those seronegative on admission and vaccinated, seroconversion rates were 100% (5/5), 90.9% (10/11), 100% (8/8) in measles, mumps and rubella vaccine, respectively. Of 265 vaccinated students parotitis was detected in one female student, arthralgia was observed in three students (1.1%) and myalgia in two (0.7%), and 240 students reported no side effects. We detected the unreliable historical screening and high seroprevalence of measles, mumps and rubella in prevaccine era for mumps and rubella and, safety of MMR vaccination in medical students in Turkey.