Effectiveness and safety of immunization with live-attenuated and inactivated vaccines for pediatric liver transplantation recipients

BackgroundLiver transplantation recipients are at high risk for severe complications due to infections because of being treated with immunosuppressive drugs that affect the immune system. Vaccination for liver transplantation candidates is generally recommended before surgery, but the opportunities for vaccination prior to transplantation in pediatric candidates are often limited by severe disease conditions.MethodsThe participants in this study comprised 39 pediatric recipients of living donor liver transplantation performed between 2005 and 2013. Criteria for administering live-attenuated (measles, rubella, mumps, and varicella) and inactivated (hepatitis B, pertussis, and Japanese encephalitis) vaccines were as follows: (1) >1 year after transplantation; (2) no use of systemic steroids to treat acute rejection within the last 6 months; (3) serum trough concentration of tacrolimus <5 ng/mL; (4) no severe immunosuppression according to blood examinations; and (5) provision of written informed consent. Median age at transplantation was 17 months, and median period from transplantation to the beginning of immunization was 18 months.ResultsSeroprotection rates for measles, rubella, mumps, varicella, hepatitis B, pertussis, and Japanese encephalitis after post-transplant immunization were 44% (11/25), 70% (19/27), 48% (12/25), 32% (6/19), 83% (19/23), 87% (13/15), and 88% (7/8), respectively. Seroprotection rates for measles, rubella, mumps, and varicella after second vaccination for recipients with primary vaccine failure after first vaccination were 100% (8/8), 50% (1/2), 71% (5/7), and 50% (5/10), respectively. While four recipients contracted mumps and eight contracted varicella before immunization, one recipient developed varicella after immunization. No serious systemic adverse events were observed in vaccinated recipients.ConclusionsSeroprotection rates for measles, mumps, and varicella appeared low in children after the first post-transplantation vaccination. Immunizations with four live-attenuated and three inactivated vaccines were safe and effective for pediatric liver transplantation recipients who were not severely immunosuppressed.     

Updated data on effective and safe immunizations with live-attenuated vaccines for children after living donor liver transplantation

BackgroundAlthough immunizations using live-attenuated vaccines are not recommended for children post-liver transplant due to their theoretical risks, they will inevitably encounter vaccine-preventable viral diseases upon returning to real-life situations. The window of opportunity for vaccination is usually limited prior to transplantation because these children often have unstable disease courses. Also, vaccine immunity does not always persist after transplantation.MethodsBeginning in 2002, subcutaneous immunizations with four individual live-attenuated vaccines (measles, rubella, varicella, and mumps) to pediatric patients following living donor liver transplantation (LDLT) were performed for those who fulfilled the clinical criteria, including humoral and cell-mediated immunity. Written informed consent was collected. We included the study on 70 immunizations for 18 cases that we reported in 2008 (Shinjoh et al., 2008).ResultsA total of 196 immunizations were administered to 48 pediatric post-LDLT recipients. Of these, 144 were first immunizations and 52 were repeated immunizations following LDLT. The seroconversion rates at the first dose for measles (AIK-C), rubella (TO-336), varicella (Oka), and mumps (Hoshino) were 100% (36/36), 100% (35/35), 70% (23/33), and 75% (24/32), respectively. Antibody levels did not fall over time in patients immunized with rubella vaccine. Three mild cases of breakthrough varicella were observed. Two cases with transient parotid gland swelling were observed after mumps immunization. Two admissions because of fever at 2–3 weeks after the measles vaccine were reported but the patients had no symptoms of measles.ConclusionsImmunizations using selected live-attenuated vaccines were safe and effective for post-LDLT children who were not severely immunosuppressed. However, with the exception of rubella, repeated immunization may be necessary.     

Antibody titers against measles, rubella, mumps and varicella-zoster viruses in medical students]

It is important to identify and immunize susceptible students who have clinical practice to prevent and control hospital infections. The antibody titers to measles, rubella, mumps and varicella viruses were measured in 1,139 students(417 men, 722 women, average age 21.3+/-2.7 yr old)including 510 medical students, 442 nursing students and 187 students of the School of Medical Technology in Kurume University. Antibodies against measles virus were detected by particle agglutination assay(PA), those against rubella virus by hemagglutination inhibition assay(HI), and those against mumps and varicella viruses by enzyme-linked immunosorbent assay(EIA). The serological susceptibilities to measles, rubella, mumps and varicella viruses were 112(9.8%), 112(9.8%), 163(14.3%)and 73(6.4%), respectively. The serological susceptibilities to measles, rubella and mumps viruses in male students were not different from those in female students. The susceptibility to varicella virus in female students was significantly higher than that in male students. After susceptible students were recommended to have vaccinations against each virus, the vaccination rate of the students without antibody was 99.1%. The history of infection and vaccination against the viruses were examined by self-recorded questionnaires in 406 students from all disciplines. The serological susceptibility of students with positive vaccination history was 11.1% for measles, 6.8% for rubella, 18.3% for mumps, and 4.9% for varicella. The serological susceptibility of students with a positive infection history was 5.7% for measles, 3.4% for rubella, 2.9% for mumps, and 4.9% for varicella. In the self-recorded questionnaire, the rate of unknown infection and vaccination histories were 57.5% and 71.6% for measles, 52.5% and 68.4% for rubella, 34.3% and 75.6% for mumps, and 27.1% and 80.5% for varicella, respectively. In conclusion, these data confirm that it is essential to assess immune status against measles, rubella, mumps and varicella in students who have clinical practice in hospital regardless of infection or vaccination history. Accordingly, susceptible students should be vaccinated to prevent those viral infections in hospital.     

Immune response to simultaneous administration of a combined measles,mumps and rubella vaccine with booster doses of diphtheria-tetanus and poliovirus vaccine

A combined vaccine against measles (Edmonston-Zagreb 19 strain), mumps (Rubini strain) and rubella (Wistar RA 27/3 strain) was administered to a group of 46 children aged 10–12 months simultaneously with booster doses of compulsory diphtheria-tetanus toxoid and oral poliovirus vaccine. A second group of 53 children aged 15–24 months who had received booster doses of the compulsory vaccines 5 to 12 months before was also vaccinated.The same seroconversion rates (100%) and similar antibody titers for rubella were observed in both groups. The same seroconversion rates for mumps (93%) and similar rates for measles (98 and 94%) were observed in the two groups.Significantly lower antibody titers for measles and mumps were found in the first group, but they were compensated by an earlier protection, a reduction of number of visits for immunization, costs for the community, and improvement in parental compliance.These results confirm that Edmonston-Zagreb 19 and Rubini strains are still immunogenic even when they are combined with Wistar RA 27/3 strain. Moreover, a long term follow-up in order to verify the persistence of protective antibody levels in both groups of children, could suggest that combined measles, mumps and rubella vaccine could be given earlier (at 10–12 months of age), simultaneously with booster doses of diphtheria and tetanus toxoid and of trivalent oral poliovirus vaccine.     

Fully vaccinated children are rare: immunization coverage and seroprevalence in Austrian school children

Vaccination coverage for vaccine-preventable diseases in Austria as well as in many Central European countries has been reported to be too low to eradicate such diseases and prevent further outbreaks. Austria lacks an adequate surveillance system to monitor prevalence of the diseases, the vaccination coverage and seroconversion. School children aged 10–14 years (n = 1077) were recruited in all four schools in the city of Schwaz, Austria, to present their vaccination documents and to give blood for serological testing (diphtheria, pertussis, measles, mumps, rubella, varicella). All participants received a report with a personal guideline for (re-) vaccination. Overall vaccination coverage was 86.4% for measles, 85.5% for mumps and 35.0% for rubella. Tetanus vaccination coverage was 98.4% for the first, 97.8% for the second and 96.7% for the third dose, while 55.4% of the study subjects received the recommended two booster injections. For diphtheria the corresponding vaccination coverage was found to be almost identical. Pertussis coverage was lower in general (first dose: 90.9%; second dose: 89.0%; third dose: 86.5%). Oral poliomyelitis vaccination showed a coverage of 98.6, 96.5, 95.3%, with 78.7% receiving the fourth dose. Overall 38.7% were classified as fully vaccinated. Seropositivity for measles was found in 90.4%, for mumps in 61.8%, for rubella in 82.3%, for diphtheria in 65.8%, for pertussis in 35.6% and for varicella in 95.0%. In summary, fully vaccinated children are rare and intensive public health efforts will be necessary to reach higher levels of immunity and prevent further outbreaks.     

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3...     

Vaccination coverage and immunity levels against vaccine-preventable diseases in male Air Force recruits in Greece

AimData about susceptibility rates in young adults are scarce. We estimated the complete vaccination rates, timeliness of vaccinations and susceptibility rates among male military recruits in Greece.MethodsA standardized form was used to collect data. Immunity against measles, rubella, varicella, hepatitis A and hepatitis B was serologically estimated.ResultsWe studied 385 recruits with a mean age of 23.5 years (range: 18.3–29.9 years). Complete vaccination rates were 94.3% for measles, 100% for rubella, 15% for varicella, 73.9% for hepatitis A and 96.5% for hepatitis B. Only 10.8% of participants were fully vaccinated against all five diseases. Timely vaccination was 47.2% for measles, 89.3% for rubella and 48.1% for hepatitis B. Recruits >23 years had a 1.5-fold increased probability for incomplete vaccinations compared to younger recruits. Laboratory-confirmed immunity rates were 80% against measles, 85.7% against rubella, 85.2% against varicella, 69.4% against hepatitis A and 77.1% against hepatitis B. It is estimated that approximately 388,696 persons aged 18–30 years are susceptible to measles, 277,640 persons to rubella, 287,736 persons to varicella, 595,664 persons to hepatitis A and 444,224 persons to hepatitis B in Greece.ConclusionOur study showed that young adults have significant immunity gaps against measles, rubella, varicella, hepatitis A and hepatitis B. Complete vaccination rates were suboptimal against hepatitis A and varicella. Strategies to access young adults and increase immunity rates through catch-up vaccination services should be investigated. A third dose of MMR vaccine should be considered for young adolescents in Greece.     

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).     

A double-blind,randomized, controlled,multi-center safety and immunogenicity study of a refrigerator-stable formulation of VARIVAX®

ObjectiveVARIVAX® (varicella virus vaccine, live Oka/Merck, Merck & Co., Inc., Kenilworth, NJ, USA) was originally licensed as a frozen formulation. A refrigerator-stable formulation of VARIVAX was subsequently developed to allow for increased availability of the product around the world. The objective of this study (V210-051) was to demonstrate that the safety, tolerability and immunogenicity profile of the refrigerator-stable formulation of VARIVAX was similar to the frozen formulation.MethodsIn this double-blind, randomized, multicenter study, healthy 12- to 23-month-old children with negative vaccination and clinical histories for measles, mumps, rubella, varicella, and zoster were vaccinated with either a refrigerator-stable formulation of VARIVAX (at two dosage levels; 8000 PFU [N = 320] or 25,000 PFU [N = 315]) or the frozen formulation of VARIVAX (10,000 PFU, N = 323) given concomitantly with M-M-RII® (measles, mumps, and rubella virus vaccine live, Merck & Co., Inc., Kenilworth, NJ, USA). Children were followed for 42 days after vaccination for adverse experiences. Immunogenicity was evaluated 6 weeks after vaccination.ResultsThe refrigerator-stable formulation of VARIVAX was generally well tolerated. The incidence of adverse experiences was similar between all three groups. No vaccine-related serious adverse experiences were reported with any of the vaccine formulations. The immune response (percentage of subjects with varicella antibody titers ≥5 gpELISA units) for both refrigerator-stable formulations of VARIVAX at 6 weeks postvaccination was similar to that of the frozen formulation. Administration of either refrigerator-stable formulation of VARIVAX with M-M-RII yielded seroconversion rates and GMTs for measles, mumps and rubella that were comparable to those achieved after administration of the frozen formulation of VARIVAX with M-M-RII.ConclusionThe safety, tolerability, and immunogenicity profile of the refrigerator-stable varicella vaccine was similar to that of the frozen formulation.     

A population-based case–control study on viral infections and vaccinations and subsequent multiple sclerosis risk

Viral infections are probably involved in the pathogenesis of multiple sclerosis (MS). A recent cohort study in the Gothenburg population revealed no change in MS incidence associated with the introduction of the Swedish measles, mumps and rubella vaccination programmes. The aim of the present study was to clarify whether these infections or vaccinations, and two other infections, varicella and infectious mononucleosis, influence MS risk. We performed a population-based case–control study in Gothenburg that included 509 MS cases and 2,067 controls, born 1959–1986. Data on infections and vaccinations were obtained from questionnaires and from child health and school health records. We found no significant associations between measles, mumps, rubella or varicella and MS risk. These results were consistent between the two source materials. Infectious mononucleosis was associated with significantly higher MS risk (odds ratio 2.03, 95% CI 1.52–2.73). Overall, there was no significant association between measles-mumps-rubella (MMR) vaccination and MS risk, while those MMR vaccinated before age ten only were at significantly higher MS risk (odds ratio 4.92, 95% CI 1.97–12.20). Those MMR vaccinated both before and after age ten had intermediate MS risk. Infection with measles, mumps, rubella and varicella did not influence MS risk in contrast to infectious mononucleosis which conferred doubled MS risk. The association with ‘early’ MMR vaccination only was an isolated finding, limited by a small number of subjects and multiple testing. Most likely this was a chance finding. Future studies could investigate it on an a priori basis.     

Seroprevalences of antibodies against pertussis,diphtheria, tetanus,measles, mumps and rubella: A cross-sectional study in children following vaccination procedure in Guangzhou,China

This study investigated the concentrations and seroprevalence of immunoglobulin G (IgG) antibodies against pertussis, diphtheria, tetanus, measles, mumps and rubella among children in Guangzhou, China. We conducted a cross-sectional study focusing on the post-vaccination immune statuses of children on scheduled immunisation. Human IgG antibody against six diseases were measured using commercial enzyme-linked immunosorbent assay kits. Of 620 subjects, the male-to-female ratio was 2.04 (416/204). Seroprevalence (81.97% vs 90.20%) and IgG concentrations (686.55 IU/mL vs 884.26 IU/mL, P < 0.05) for measles, tetanus (0.94 IU/mL vs 1.21 IU/mL) and rubella (34.33 IU/mL vs 47.37 IU/mL) were all higher in females. No differences based on sex were observed in the seroprevalence and IgG concentrations for anti-pertussis antibodies, anti-diphtheria antibodies and anti-mumps. Slight increase in seroprevalence and IgG concentration occurred with anti-pertussis antibodies after primary and booster vaccinations (from 0.00% [1 m], 5.45% [6 m], to 17.14% [1.5 yr]; and from 8.57% [5 yr] to 15.79% [6 yr]). Although no booster vaccination was given after age 6 yr, the seroprevalence and IgG concentration for anti-pertussis antibodies remained relatively stable. For diphtheria, tetanus, measles and rubella, seroprevalence reached their peaks after the primary and first booster vaccination. A plateau occurred after age 1.5 yr with a declining trend in subjects >8–10 yr. The IgG concentrations of these 4 pathogens showed a dramatic increase after primary vaccination, with steadily declining trends thereafter. For mumps, subjects showed increased seroprevalence and IgG concentration after the primary mumps-containing vaccination in 1.5-yr-olds (from 7.14% to 57.14%; 52.13 IU/mL to 214.18 IU/mL); however, following that low seroprevalence levels (from 42.86% to 80.00%) were observed. The post-vaccination immune statuses against diphtheria, tetanus, measles and rubella were relatively satisfactory, compared to those against pertussis and mumps. Booster vaccination against pertussis and mumps at appropriate time should be considered.     

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.     

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     

Immunogenicity and safety of a combined measles,mumps, rubella and varicella live vaccine (ProQuad®) administered concomitantly with a booster dose of a hexavalent vaccine in 12–23-month-old infants

BackgroundConcomitant administration of vaccines can facilitate vaccination uptake, provided that no clinically significant effect on either vaccine is identified. We investigated the concomitant administration, during the second year of life, of one dose of the combined measles, mumps, rubella and varicella vaccine (ProQuad^®) with a booster dose of a hexavalent vaccine.MethodsIn this multicentre, open-label study, participants were randomized to 3 groups: Group 1, concomitant administration of one dose of ProQuad^® and a booster of hexavalent vaccine; Group 2, one dose of ProQuad^® alone; Group 3, a booster dose of hexavalent vaccine alone. Two serum samples were collected, within 7 days prior to vaccination and Days 42–56 post-vaccination for antibody testing.ResultsAntibody response rates to measles, mumps, rubella, varicella, hepatitis B and Haemophilus influenzae type b following concomitant administration of ProQuad^® and hexavalent vaccine were non-inferior compared with those following the individual vaccines. Antibody response rates to these antigens were all >95% in all groups. Antibody titres for the pertussis antigens following concomitant administration were also non-inferior to those following the individual vaccines. Antibody titres for the other valences were numerically comparable between groups with the exception of hepatitis B, Haemophilus influenzae type b, tetanus and poliomyelitis, which were higher in the concomitant than in the non-concomitant groups. The safety profiles of each vaccination regimen were comparable, with the exception of solicited ProQuad^®-related injection-site reactions (Days 0–4), which occurred more frequently in the concomitant than in the non-concomitant groups.ConclusionThese immunogenicity data support the concomitant administration of ProQuad^® with a hexavalent vaccine. The safety profile of concomitant ProQuad^® and hexavalent vaccination was also in line with that of the individual Summaries of Product Characteristics.     

Seroprevalence of measles, mumps, rubella and varicella among staff of a hospital in Riyadh, Saudi Arabia

This study aimed at screening immune status of Health Care Workers (HCWs) against measles, mumps, rubella, and varicella, and assessing the reliability of the history of previous illness due to these infections or vaccination against them as an indicator of the immune status, as checked by laboratory tests. Demographic data, history of previous illnesses and previous vaccinations were collected using a self-administered questionnaire. Also, serologic screening was done for these infections. Antibodies tested using ELISA. Among tested hospital staff, 71.8%, 60.3%, 47.9% and 68.4% reported history of infection or vaccination against measles, mumps, rubella and varicella respectively, while laboratory results proved that 4.5%, 10.8%, 12.9% and 11.3% were susceptible respectively. Susceptibility was most frequent among housekeeping staff against measles and varicella, while administrative staff were the most susceptibles to mumps, and nurses were the most susceptibles to rubella. Sensitivity of past history of illness as an indicator of the immune status, was found to be (85%, 83%, 66%, 86%); Specificity was (81%, 81%, 89%, 87%); Positive Predictive value (PV) was (99%, 98%, 98%, 98%) and Negative PV was (16%, 29%, 22%, 39%) for measles, mumps, rubella and varicella respectively. Screening for measles, mumps, rubella and varicella among hospital staff is mandatory to detect those who are susceptible for infections and should be vaccinated, and so preventing transmission of these infections to their colleagues or patients.     

Risk of febrile seizure after measles–mumps–rubella–varicella vaccine: A systematic review and meta-analysis

BackgroundConsidering the febrile seizure rate, there is no longer a clear preference for use of measles–mumps–rubella–varicella (MMRV) vaccine over separate measles–mumps–rubella (MMR) and varicella (V) vaccine. This work was undertaken to assess the risk of febrile seizure after MMRV vaccine in children.MethodsWe searched PubMed, Embase, BIOSIS Previews, Scopus, Web of Science, Cochrane Library and other databases through 12 December 2014. Meta-analysis was conducted using R version 3.1.2 and Stata version 12.0.ResultsA total of thirty-nine studies were included. Thirty-one published or unpublished clinical trials involving about 40,000 subjects did not show significant differences in incidence of febrile seizure or vaccine related febrile seizure between MMRV and MMR with or without varicella vaccine after any doses, in the risk windows of 0–28, 0–42 or 0–56 days and 7–10 days. In addition, these studies showed that the receipt of concomitant use of MMRV and other pediatric vaccines was not a significant predictor of febrile seizure. Eight post-marketing observations involving more than 3,200,000 subjects were included. No evidence suggested elevated risk of febrile seizure associated with MMRV vaccine among children aged 4–6 years old during 7–10 days or 0–42 days after vaccination. However, an approximately 2-fold increase in risk of seizure or febrile seizure during 7–10 days or 5–12 days after MMRV vaccination was found among children aged 10–24 months, although the highest incidence of seizure was still lower than 2.95‰.ConclusionsFirst MMRV vaccine dose in children aged 10–24 months was associated with an elevated risk of seizure or febrile seizure. Further post-marketing restudies based on more rigorous study design are needed to confirm the findings.     

Prevalence of childhood exanthematic disease antibodies in paramedical students: need of vaccination

The immunity to common childhood exanthematic diseases such as varicella, rubella, mumps and measles was evaluated in 1024 students of the degree courses of health professions at Padua University Medical School. Subjects were subdivided according to gender and age (25 years old or less, and older than 25 years). Results showed that the prevalence of positive antibodies (IgG) to varicella and rubella (94.1 and 94.5%, respectively) was significantly higher (p<0.001) than mumps (78.6%) and measles (86.3%). In addition, measles showed a significant higher prevalence than mumps (p<0.001). Prevalence of positive antibodies to rubella in females (97.4%) was significantly higher (p<0.001) than males (87.5%), but only if aged 25 years or less. Furthermore, males older than 25 years were significantly more immune (p<0.001) to measles (93.0%) than younger ones (84.3%). A vaccination strategy was applied but compliance was less than 50%; in addition, about 40.0% of vaccinated subjects eluded control after vaccination. Seroconversion after vaccine appeared high for rubella, mumps and measles (92.3, 88.9 and 88.1%, respectively), but low for varicella (43.8%).     

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.     

MMR and MMRV vaccines

Measles, mumps, rubella and varicella are viral infections which can implicate seriously long-term sequelae of infected individuals or even the unborn child. Vaccines against the individual diseases have long been available. Global measles vaccination is estimated to have prevented more than 20 million deaths during 2000–2015. During the same time period, measles incidence decreased from 146 to 36 cases per million populations. Today vaccinations against measles, mumps, rubella and varicella are now carried out mainly with combination vaccines. These are today known as immunogenic and safe. MMRV had similar immunogenicity and overall safety profiles to MMR administered with or without varicella vaccine. This issue provides a review of the different vaccines, mode of administration, catch up immunization and postexposure prophylaxis as well as contraindications and adverse effects of the immunization against measles, mumps, rubella, and varicella. The article presents an overview of important information of preventing these diseases with a focus on the existing combination vaccines.     

Seroprotection to vaccine‐preventable diseases among workers at a Victorian tertiary hospital

Objective : To determine seroprotection for the vaccine‐preventable diseases (VPDs) measles, mumps, rubella, varicella and hepatitis B among new employees seen at a Victorian tertiary hospital staff clinic. Methods : Employees who presented to the staff clinic for immunisation assessment between 1 January 2012 and 31 December 2013 were included. Demographic data, self‐reported disease history and previous vaccination status were reviewed retrospectively to determine impact on serological results. Results : A total of 1,901 new employees were included, 83% of whom were at risk of direct contact with blood or body substances. Overall, the proportion of workers seropositive to measles was 88%, mumps 90%, rubella 78%, varicella 93% and hepatitis B 80%. Staff born before 1966 were more likely to have positive measles or mumps serology but negative rubella or hepatitis B serology (p<0.05 for each). Staff who self‐reported measles (99% vs. 93%, p=0.03) or varicella infection (98% vs. 92%, p<0.001) were more likely to be seropositive, but those reporting previous vaccination to measles, mumps or rubella were no more likely to be seropositive. Conclusions and implications : This study demonstrated levels of seropositivity of 78–93% for the five VPDs. Despite recognised limitations of serological testing, 10–20% of new employees to a healthcare institution lacking seroprotection represents a potentially unacceptable risk of nosocomial transmission of these VPDs. Our findings support ongoing serological testing of new healthcare staff at risk of direct contact with blood or body substances.