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Background: In recent years, multiple outbreaks of measles associated with vaccine hesitancy occurred in high-income countries, where measles incidence had previously been low. Most safety data about the measles, mumps and rubella (MMR) vaccine are derived from studies conducted among children, whereas evidence regarding the safety profile of the vaccine in adults is scarce., Methods: In 2017, during an outbreak of measles in Europe, Israeli travellers to high-risk locations who were incompletely vaccinated, were urged to complete the two MMR vaccination schedule before their travel. In this prospective cohort study, we analysed adverse events (AEs) of MMR and MMRV (measles, mumps, rubella and varicella) vaccines among these travellers. All participants were followed up using structured questionnaires 2-4 weeks after vaccination., Results: Seven hundred and eighty-five adult travellers whose median age was 49.2 years were vaccinated and followed up. Any AEs were reported by 25.2% of all participants; 11.6% reported local AEs, and 18.6% reported systemic AEs, none of which were severe. In general, AEs were much more common among female travellers (19.4% of males vs 30.1% of females (P < 0.001)). Local AEs, overall systemic AEs, headache and arthralgia were much more common among females, whereas rates of general malaise and fever were not statistically different between genders. We did not observe any significant differences in the rates of total, local or systemic AEs between the MMR and MMRV vaccines. Higher rates of systemic AEs were observed among participants who were younger and probably immunized once with MMR compared to older vaccines immunized once to measles only and to those who were never immunized., Conclusions: The current study demonstrated low rates of systemic AEs and no serious AEs following either MMR or MMRV administration. More AEs were reported among females, and rates of AEs were similar after either MMR or MMRV., (© The Author(s) 2021. Published by Oxford University Press on behalf of International Society of Travel Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: A third measles-mumps-rubella vaccine (MMR) dose (MMR3) is recommended in the United States for persons at increased risk for mumps during outbreaks. MMR3 is also likely given to persons who might have received 2 doses of MMR but lack documentation. Since MMR3 safety data are limited, we describe adverse events in persons receiving MMR3 in a nonoutbreak setting., Methods: Young adults with 2 documented MMR doses were administered MMR3. From 2 weeks before until 4 weeks after MMR3 receipt, participants reported daily on 11 solicited, common symptoms potentially associated with MMR. Weekly rate differences in post- vs prevaccination (baseline) were evaluated by Poisson regression. Baseline rates were subtracted from postvaccination rates of significantly different symptoms to estimate the number and percentage of participants with excess risk for symptoms post-MMR3. Descriptive analyses were performed for 3 postvaccination injection-site symptoms., Results: The 662 participants were aged 18-28 years (median = 20 years); 56% were women. Headache, joint problems, diarrhea, and lymphadenopathy rates were significantly higher postvaccination vs baseline. We estimate that 119 participants (18%) reported more symptoms after MMR3 than prevaccination. By symptom, 13%, 10%, 8%, and 6% experienced increased symptoms of headache, joint problems, diarrhea, and lymphadenopathy, respectively, after MMR3. The median onset was Days 3-6 postvaccination; the median duration was 1-2 days. One healthcare visit for a potential vaccination-related symptom (urticaria) was reported. Injection-site symptoms were reported by 163 participants (25%); the median duration was 1-2 days., Conclusions: Reported systemic and local events were mild and transient. MMR3 is safe and tolerable among young adults., (Published by Oxford University Press for the Infectious Diseases Society of America 2020.)

Characteristics of vaccine-associated rash illness (VARI) and confirmed measles cases were compared during a measles outbreak. Although some clinical differences were noted, measles exposure and identification of the vaccine strain were helpful for public health decision-making. Rapid, vaccine strain-specific diagnostic assays will more efficiently distinguish VARI from measles., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

The measles-mumps-rubella (MMR) vaccine is generally well tolerated, and reports of anaphylaxis to the vaccine are rare. IgE-mediated reactions to vaccines are often caused by additives or residual vaccine components. An inability to obtain proper immunizations can be a disqualifying component to military service. We report a case of anaphylaxis to the MMR vaccine in a new military recruit sensitized to gelatin IgE., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Association of Military Surgeons of the United States. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: MMR II (M-M-R II [Merck & Co, Inc.]) is currently the only measles, mumps, and rubella (MMR) vaccine licensed in the United States. A second MMR vaccine would mitigate the potential risk of vaccine supply shortage or delay. In this study, we assessed the immunogenicity and safety of another MMR vaccine (MMR-RIT [Priorix, GlaxoSmithKline]) compared with those of the MMR II in 12- to 15-month-old children who received it as a first dose., Methods: In this phase III, observer-blinded, noninferiority, lot-to-lot consistency clinical trial (ClinicalTrials.gov identifier NCT01702428), 5003 healthy children were randomly assigned to receive 1 dose of MMR-RIT (1 of 3 production lots) or MMR II along with other age-recommended routine vaccines. We evaluated the immunogenicity of all vaccines in terms of antibody concentrations (by using an enzyme-linked immunosorbent assay or electrochemiluminescence assay) and/or seroresponse rates 43 days after vaccination. We also assessed the reactogenicity and safety of the vaccines., Results: Immunoresponses after vaccination with MMR-RIT were robust and noninferior to those after vaccination with the MMR II. Immunogenicity of the 3 production lots of MMR-RIT was consistent; more than 97% of the children had a seroresponse to MMR components. The coadministered vaccines elicited similar immunoresponses in the MMR-RIT and MMR II groups. Both MMR vaccines resulted in comparable reactogenicity profiles, and no safety concerns were detected., Conclusions: If licensed, the MMR-RIT could provide a valid option for the prevention of measles, mumps, and rubella in children in the United States and would reduce potential risks of a vaccine shortage., (© The Author(s) 2019. Published by Oxford University Press on behalf of The Journal of the Pediatric Infectious Diseases Society.)

Background: Waning of vaccine-induced immunity is considered to play a central role in the reemergence of mumps among vaccinated young adults. The aim of the present study was to investigate antibody responses and safety of a third dose of measles-mumps-rubella vaccine (MMR-3) in 150 young adults. Antibody levels were related to a surrogate of protection based on preoutbreak serum antibody levels in 31 persons with and 715 without serological evidence of mumps., Methods: Mumps virus-specific immunoglobulin G (IgG) antibody responses and mumps virus-neutralizing antibody responses (based on the focus-reduction neutralizing test) against both the Jeryl Lynn mumps virus vaccine strain (hereafter, the "vaccine strain") and the MuVi/Utrecht.NLD/40.10 outbreak strain (hereafter, the "outbreak strain") were determined, and vaccine safety was evaluated., Results: Four weeks following MMR-3 receipt, levels of IgG, anti-vaccine strain, and anti-outbreak strain antibodies increased by a factor of 1.65, 1.34, and 1.35, respectively. Although antibody levels decreased 1 year later, they were still above the baseline level by a factor of 1.37, 1.15, and 1.27, respectively. Based on the surrogate protective antibody cutoff, significantly more participants were protected against mumps virus infection up to 1 year after vaccination (ie, they had antibody levels above the presumed threshold for herd immunity)., Conclusions: MMR-3 receipt increased antibody levels that may protect against mumps virus infection for longer than previously assumed and is expected to be a good and safe intervention for controlling a mumps outbreak., Clinical Trials Registration: 2016-001104-36; NTR5911., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: People's intentions to use vaccines are influenced by their beliefs about both the specific vaccine and the disease it prevents. In the absence of firm beliefs about Zika virus (ZIKV), individuals may base their intentions to vaccinate against it on beliefs about other vaccines, and specifically the misbelief that MMR causes autism., Methods: A survey of 3337 Americans, using a random-digit-dialing sample of landline telephone households and cell-phones., Results: Intentions to use a Zika vaccine were influenced by beliefs about Zika, science in general, and MMR. Intentions were positively influenced by perceived severity of and vulnerability to Zika, as well as belief in science's efficacy. However, intentions were negatively influenced by the belief that MMR causes autism in children., Conclusion: The misbelief about MMR and autism may reduce people's intentions to use a new Zika vaccine. However, perceptions of severity of and vulnerability to Zika may increase intentions. Implications for science educators and public health officials are discussed.

Background: Patients increasingly benefit from immunosuppressive/immunomodulatory medications for a range of conditions allowing them a lifestyle similar to healthy individuals, including travel. However, the administration of live vaccines to immunodeficient patients bears the risk of replication of the attenuated vaccine microorganism. Therefore, live vaccines are generally contraindicated on immunosuppression. Data on live vaccinations on immunosuppressive/immunomodulatory medication are scarce. We identified all travellers seeking pre-travel advice in three Swiss travel clinics with a live vaccine during immunosuppressive/immunomodulatory therapy to ascertain experienced side effects. A retrospective and multi-centre study design was chosen to increase the sample size., Methods: This study was conducted in the travel clinics of the University of Zurich; the Swiss TPH, Basel; and Geneva University Hospitals. Travellers on immunosuppressive/immunomodulatory therapy who received live vaccines [yellow fever vaccination (YFV), measles/mumps/rubella (MMR), varicella and/ or oral typhoid vaccination (OTV)] between 2008 and 2015 were identified and interviewed. A total of 60 age- and sex-matched controls (matched to Basel/Zurich travel clinics travellers) were included., Results: Overall, 197 patients were identified. And 116 patients (59%) and 60 controls were interviewed. YFV was administered 92 times, MMR 21 times, varicella 4 times and OTV 6 times to patients on immunosuppressive/immunomodulatory therapy. Most common medications were corticosteroids (n = 45), mesalazine (n = 28) and methotrexate (n = 19). Live vaccines were also administered on biological treatment, e.g. TNF-alpha inhibitors (n = 8). Systemic reactions were observed in 12.2% of the immunosuppressed vs 13.3% of controls; local reactions in 7.8% of the immunosuppressed vs 11.7% of controls. In controls, all reactions were mild/moderate. In the immunosuppressed, 2/21 severe reactions occurred: severe local pain on interferon-beta and severe muscle/joint pain on sulfasalazine., Conclusion: Safety of live vaccines given to immunosuppressed patients cannot be concluded. However, it is re-assuring that in the examined patient groups no serious side effects or infections by the attenuated vaccine strain occurred., (© International Society of Travel Medicine, 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com)

Background: In 2013-2014, a measles outbreak spread through the Netherlands. To protect young infants, measles-mumps-rubella (MMR) vaccination was offered to those aged 6-14 months in municipalities with routine first-dose MMR vaccine coverage of <90%. We assessed the tolerability of this early administration of MMR vaccine., Methods: After study entry (n = 1866), parents of eligible infants (n = 10 097) completed a questionnaire (n = 1304). For infants who received an early MMR vaccine dose (n = 962), we asked for information about adverse events (AEs) associated with the dose. AE frequencies were compared between infants aged 6-8, 9-11, and 12-14 months. Using multivariable logistic regression, we assessed the association between the risk of AEs and age at early MMR vaccination., Results: The response rate was 13%. Parents of 59 infants (6.1%) and 350 infants (36.4%) who received early MMR vaccination reported local and systemic AEs, respectively. Parents of infants vaccinated at 6-8 months of age reported systemic AEs less frequently (32%) than parents of children vaccinated at 9-11 months (45%) and 12-14 months (43%) of age (P= <.001). For local AEs, there were no differences (5%, 7%, and 10%, respectively;P= .08). Compared with vaccination at 6 months, all older infants except those aged 14 months showed an increased risk for any AE and for systemic AEs starting 5-12 days after vaccination., Conclusions: Early MMR vaccination is well tolerated, with the lowest AE frequencies found in infants aged 6-8 months. It is a safe intervention for protecting young infants against measles., (© The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: M-M-R(TM)II (MMRII; Merck & Co) is currently the only measles-mumps-rubella (MMR) vaccine licensed in the United States. Another licensed vaccine would reinforce MMR supply. This study assessed the immunogenicity of a candidate vaccine (Priorix(TM), GlaxoSmithKline Vaccines [MMR-RIT]) when used as a first dose among eligible children in the United States., Methods: In this exploratory Phase-2, multicenter, observer-blind study, 1220 healthy subjects aged 12-15 months were randomized (3:3:3:3) and received 1 dose of 1 of 3 MMR-RIT lots with differing mumps virus titers (MMR-RIT-1 [4.8 log10]; MMR-RIT-2 [4.1 log10]; MMR-RIT-3 [3.7 log10] CCID50) or MMRII co-administered with hepatitis A vaccine (HAV), varicella vaccine (VAR) and 7-valent pneumococcal conjugate vaccine (PCV7). Immune response to measles, mumps, and rubella viruses was evaluated at Day 42 post-vaccination. Incidence of solicited injection site, general, and serious adverse events was assessed., Results: Seroresponse rates for MMR vaccine viral components in MMR-RIT lots were 98.3-99.2% (measles), 89.7-90.7% (mumps), and 97.5-98.8% (rubella), and for MMRII were 99.6%, 91.1%, and 100%, respectively. Immune responses to HAV, VAR, and PCV7 were similar when co-administered with any of the 3 MMR-RIT lots or MMRII. There were no apparent differences in solicited or serious adverse events among the 4 groups., Conclusions: Immune responses were above threshold levels for projected protection against the 3 viruses from MMR-RIT lots with differing mumps virus titers. MMR-RIT had an acceptable safety profile when co-administered with HAV, VAR, and PCV7., Clinical Trials Registration: NCT00861744; etrack; 111870., (© The Author 2014. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society.)

Background: Limited data exist on the safety of the measles, mumps, and rubella (MMR) vaccine in adults. We reviewed reports of adverse events (AEs) to the Vaccine Adverse Event Reporting System (VAERS) to assess safety in this previously understudied group., Methods: VAERS is the national spontaneous vaccine safety surveillance system coadministered by the Centers for Disease Control and Prevention and the US Food and Drug Administration. We searched the VAERS database for US reports of adults aged ≥19 years who received the MMR vaccine from 1 January 2003 to 31 July 2013. We clinically reviewed reports and available medical records for serious AEs, pregnancy reports, and reports for selected prespecified outcomes., Results: During this period, VAERS received 3175 US reports after MMR vaccine in adults. Of these, 168 (5%) were classified as serious, including 7 reports of death. Females accounted for 77% of reports. The most common signs and symptoms for all reports were pyrexia (19%), rash (17%), pain (13%), and arthralgia (13%). We did not detect any new safety findings in empirical Bayesian data mining. We identified 131 reports of MMR vaccine administered to a pregnant woman; the majority of these vaccinations were in the first trimester and in 83 (62%), no AE was reported., Conclusions: In our review of VAERS data, we did not detect any new or unexpected safety concerns for MMR vaccination in adults. We identified reports of pregnant women exposed to MMR, which is a group in whom the vaccine is contraindicated, suggesting the need for continued provider education on vaccine recommendations and screening., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Females typically develop higher antibody responses and experience more adverse reactions following vaccination than males. These differences are observed in response to diverse vaccines, including the bacillus Calmette-Guerin vaccine, the measles, mumps and rubella vaccine, the yellow fever virus vaccine and influenza vaccines. Sex differences in the responses to vaccines are observed across diverse age groups, ranging from infants to aged individuals. Biological as well as behavioral differences between the sexes are likely to contribute to differences in the outcome of vaccination between the sexes. Immunological, hormonal, genetic and microbiota differences between males and females may also affect the outcome of vaccination. Identifying ways to reduce adverse reactions in females and increase immune responses in males will be necessary to adequately protect both sexes against infectious diseases., (© The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Measles and rubella were common infectious diseases in Egypt during the prevaccine era. Monovalent measles vaccine was introduced in 1977, and measles vaccination coverage increased from <50% to >90% from 1980 to 1999; however, measles outbreaks continued to occur at 2- to 4-year intervals during this period. After the introduction of a second routine dose of measles vaccine as a combined measles-mumps-rubella (MMR) vaccine in 1999 and the implementation of measles immunization campaigns targeting 6- to 16-year-old children during 2000-2003, reported measles cases dramatically decreased by 2003. In 2002, Egypt established a goal to eliminate measles and rubella and to prevent congenital rubella syndrome (CRS) by 2010. Large-scale rubella and measles outbreaks in 2005-2007, however, led to a revision of the plan of action to achieve the 2010 goals. A nation-wide measles-rubella immunization campaign, targeting children, adolescents, and young adults 2-20 years old, was conducted in 2 phases during 2008-2009 and achieved coverage >95%. With the decrease to record low levels of cases of measles and rubella in 2009 and 2010, Egypt should achieve measles and rubella elimination in the near future, but high coverage(>95%) with 2 doses of measles-rubella vaccine needs to be maintained, measles-rubella surveillance strengthened, and CRS surveillance developed., (Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2011.)

Background: The low prevalence of measles antibody in human immunodeficiency virus (HIV)-infected children after immune recovery as a result of highly active antiretroviral therapy increases the risk of morbidity and mortality from disease. The objective of our study was to evaluate the efficacy and safety of revaccination with measles, mumps, and rubella (MMR) vaccine in HIV-infected children with immune recovery., Methods: Inclusion criteria were (1) HIV-infected children aged >5 years, (2) a nadir CD4 lymphocyte percentage 15% for >or=3 months after highly active antiretroviral therapy), and (4) no protective antibody against measles. Each child received 1 dose of MMR vaccine, and antibodies were measured at 4 and 24 weeks after vaccination. Protective antibodies were defined as an antimeasles immunoglobulin G (IgG) level >or=320 mIU/mL, an antimumps IgG titer >1:500, and an antirubella IgG level >10 IU/mL., Results: There were 51 participants. The mean age (+/- standard deviation) was 10.2 +/- 2.5 years. Prior to revaccination, 28 participants (55%) had baseline protective antibody to mumps, and 11 (20%) had baseline protective antibody to rubella. The prevalence of protective antibody at 4 weeks was 90%, 100%, and 78% for measles, rubella, and mumps, respectively, and then slightly decreased to 80%, 94%, and 61%, respectively, at 24 weeks after revaccination. No serious adverse reactions were attributed to revaccination., Conclusions: The majority of HIV-infected children with immune recovery can develop protective antibodies after MMR revaccination. Revaccination with MMR vaccine in HIV-infected children with immune recovery should be considered to ensure individual immunity and limit the spread of disease.

Background: Previous controversy was generated over the hypothesis that a paramyxovirus such as measles or vaccination against such viruses might be causally associated with inflammatory bowel disease (IBD). We aimed to determine if Crohn's disease (CD) or ulcerative colitis (UC) subjects are more likely to be seropositive for measles, mumps, or rubella than controls., Methods: Using our population-based University of Manitoba IBD Research Registry we recruited CD (n = 235) and UC (n = 137) subjects ages 18-50 years for a study involving detailed questionnaires and venipuncture. We accessed the population-based databases of Manitoba Health (single provincial health insurer) to get age-, gender-, and geography-matched non-IBD controls (n = 310). We used a standard enzyme-linked immunosorbent assay (ELISA) to measure serum antibodies., Results: Seropositivity for measles and mumps was similar in controls (98.1%, 78.4%, respectively) as in CD (96.2%, 72.3% respectively) and in UC (95.5%, 74.6%, respectively). However, controls were significantly more likely to be seropositive for rubella (98.1%) than were CD cases (91.0%, P < 0.0002) or UC cases (93.3%, P = 0.01). Males accounted for the significantly lower rates of seropositivity to rubella with CD. While we determined that significantly more controls than CD were vaccinated, we cannot be sure if the increased rate of rubella seropositivity in controls is secondary to wildtype or vaccine-associated infection., Conclusions: These data suggest there is no association of having acquired measles, mumps, or rubella (by natural infection or through vaccination) and CD or UC. If anything, these data may suggest some protective effect of having acquired rubella infection or vaccine against acquiring CD.

Measles-mumps-rubella (MMR) vaccines containing the Urabe strain of mumps were withdrawn in the United Kingdom in 1992 following demonstration of an increased risk of aseptic meningitis 15-35 days after vaccination. Following introduction of a replacement MMR vaccine (Priorix; GlaxoSmithKline, London, United Kingdom) in 1998, active surveillance of aseptic meningitis and convulsion was established to evaluate the risk associated with the new vaccine. No laboratory-confirmed cases of mumps meningitis were detected among children aged 12-23 months after administration of 1.6 million doses of Priorix (upper 95% confidence limit of risk: 1:437,000) in England and Wales. The upper 95% confidence limit excluded the risk found for mumps meningitis with Urabe vaccines (1:143,000 doses). No cases of aseptic meningitis were detected among children aged 12-23 months, who had received over 99,000 doses of Priorix (upper 95% confidence limit of risk: 1:27,000), in a regional database of hospital-admitted cases. This compares with an observed risk of 1:12,400 for Urabe vaccines. An elevated relative incidence of convulsion was found in the 6- to 11-day period after receipt of Priorix (relative incidence = 6.26, 95% confidence interval: 3.85, 10.18)-consistent with the known effects of the measles component of MMR vaccine-but not in the 15- to 35-day period (relative incidence = 1.48, 95% confidence interval: 0.88, 2.50) as occurred with Urabe-containing vaccines. This study demonstrates the power of active postmarketing surveillance to identify or exclude events too rare to be detected in prelicensure trials.

Background: Coverage of the Measles-Mumps-Rubella combined vaccine (MMR) has declined in recent years in the UK, following adverse publicity about possible links between the vaccine, autism, and Crohn's disease. The objectives of this study were to assess geographical variation in trends in MMR coverage and to identify the factors affecting MMR uptake at population level., Methods: We conducted an ecological study of immunization coverage by second birthday, based on routinely collected data from 1993-2004 for England. Trends in MMR uptake were assessed in 95 District Health Authorities in England over the study period. We investigated the relationship between MMR immunization uptake and deprivation, ethnicity, education, population density, rurality, and socioeconomic class., Results: Since 2000, MMR coverage has declined significantly in virtually all areas of England. Population density and deprivation were both strongly correlated with low MMR uptake. The decline in coverage since 1993-94 was significantly related to the proportion of educated population and was greater in densely populated areas., Conclusion: Decline in MMR coverage now affects most areas of England. The lowest rates of MMR coverage remain in urban areas, particularly in inner cities, which also tend to show high levels of deprivation. Public health resources should continue to target inner city areas, as well as focus on the concerns of the better educated about vaccine safety.

Background: Previous studies on vaccination and childhood leukaemia generated inconsistent results., Methods: In the Northern California Childhood Leukaemia Study, a case-control study with incident cases and matched birth certificate controls, detailed written vaccination records were collected. A total of 323 cases aged 0-14 years at diagnosis and 409 controls were included in this analysis. All vaccinations were censored on the reference date (date of diagnosis for cases and the corresponding date for matched controls). Conditional logistic regression analysis was conducted, adjusting for potential confounding factors. A primary variable of interest is the number of administrations (doses) of various types of vaccines., Results: Vaccinations against diphtheria, pertussis, tetanus, poliomyelitis, measles, mumps, and rubella were not associated with the risk of leukaemia. The odds ratio for each dose of Haemophilus influenzae type b (Hib) vaccine was 0.81 (95% CI 0.68-0.96). Compared with children who received two or fewer doses of Hib vaccine, those who received three or more doses had a significantly reduced risk of childhood leukaemia (odds ratio = 0.55, 95% confidence interval 0.32-0.94). The number of doses of hepatitis B vaccine received was not associated with leukaemia risk., Conclusions: Hib vaccination is associated with a reduced risk of childhood leukaemia. Future studies with detailed exposure assessment and large sample sizes are needed to further address the role of vaccinations in the etiology of childhood leukaemia.

The unfolding of the measles, mumps and rubella (MMR) controversy reveals some of the key features of the cultural climate affecting matters of health and illness in contemporary society. A high level of anxiety around issues of health is reflected in a heightened sense of individual vulnerability to environmental dangers (such as atmospheric pollution, electromagnetic fields, bioterrorism) and in a general aversion to risk, particularly in relation to children. This mood has proved responsive to views sceptical, if not hostile, towards science and medicine and associated professionals, particularly in the sphere of immunization. The result is that uptake of MMR vaccination in the UK has fallen, from a peak of 92% in the mid-1990s to a national level of 82% in 2003 (at the age of two); in London uptake is now less than 75%-much less in some areas-causing a significant risk of outbreaks of measles. In the USA too, the proportion of parents opting out of regulations requiring immunization as a condition of school entry has increased significantly in some areas, though these controversies appear to have had little impact so far in continental Europe.

Background: Little is known about risk perception amongst parents who have their children immunized, as opposed to those who do not. Our objective was to assess their vaccine risk perception and thereby to identify strategies to prevent further deterioration in uptake., Methods: An in-depth interview study was conducted with parents in two nurseries, one urban and one rural in Norfolk, together with a pilot study. All their children were fully immunized. Topics related to parents' vaccine risk perceptions., Results: Certain known risk characteristics were attributable to the measles, mumps and rubella vaccine, including feeling of dread, lack of control and doubt in scientific knowledge. Furthermore, this study re-emphasizes that parents lack trust in government agencies and may have doubts in the medical profession as the 'managers' of vaccine risk., Conclusions: Results highlighted an urgent need to address concerns amongst parents who immunize, to prevent them changing their practice in the face of further vaccine controversies.

Epidemiologic study of a vaccine's adverse events is not easy; so many countries have no reliable data. Vaccines containing the Urabe or Hoshino strain have been withdrawn from use in several countries. However, the data are not strong enough to form the basis of a recommendation not to use specific strains. The authors used a case-crossover design to estimate the relative risk of aseptic meningitis in children after receiving the measles-mumps-rubella vaccine in Korea. Study subjects were hospitalized children aged 8-36 months who had aseptic meningitis in 1998. Cases were confirmed by hospital chart reviews using previously defined criteria. Through a telephone survey, the authors obtained vaccination date and place information from parents' vaccination records. Study results showed that no significant risk was associated with the Jeryl Lynn or Rubini strain of the vaccine (relative risk = 0.6, 95% confidence interval (CI): 0.18, 1.97). For the Urabe or Hoshino strain, the relative risk was 5.5 (95% CI: 2.6, 11.8); the risk increased in the third week after vaccination (relative risk = 15.6, 95% CI: 5.9, 41.2) and was elevated until the sixth week. The case-crossover design was useful in confirming the risk of acute adverse events after receiving vaccines.

Monitoring of adverse events following the administration of MMR vaccine containing the Urabe mumps virus vaccine strain, to over 2 million schoolchildren (aged 6-13 years) revealed that the incidence of vaccine-associated aseptic meningitis was one case per 295 000 doses given. About 92 per cent of these children had had their primary immunization against MMR at 12 months of age and, therefore, were probably not immunologically naïve. It appears from our data that the use of the Urabe-based mumps vaccine in the booster-dose format induces much less adverse effects than usually observed following the primary immunization with it. Further studies are needed to prove this conclusively.

Background: The aim of this study was to report exploratory findings from an attempt to quantify the quality of a sample of World Wide Web (WWW) pages relating to MMR vaccine that a typical user might locate., Method: Forty pages obtained from a search of the WWW using two search engines and the search expression 'mmr vaccine' were analysed using a standard proforma. The proforma looked at the information the pages contained in terms of three categories: content, authorship and aesthetics. The information from each category was then quantified into a summary statistic, and receiver operating characteristic (ROC) curves were generated using a 'gold standard' of quality derived from the published literature. Optimal cut-off points for each of the three sections were calculated that best discriminated 'good' from 'bad' pages. Pages were also assessed as to whether they were pro- or anti-vaccination., Results: For this sample, the combined contents and authorship score, with a cut-off of five, was a good discriminator, having 88 per cent sensitivity and 92 per cent specificity. Aesthetics was not a good discriminator. In the sample, 32.5 per cent of pages were pro-vaccination; 42.5 per cent were anti-vaccination and 25 per cent were neutral. The relative risk of being of poor quality if anti-vaccination was 3.3 (95 per cent confidence interval 1.8, 6.1)., Conclusion: The sample of Web pages did contain some quality information on MMR vaccine. It also contained a great deal of misleading, inaccurate data. The proforma, combined with a knowledge of the literature, may help to distinguish between the two.