Safe immunization of allergic children against measles, mumps, and rubella

A series of 135 subjects (134 children and one adult) with documented or suspected systemic allergy were prick-tested before a measles, mumps, and rubella (MMR) vaccination. Atopic eczema was documented in 68, asthma in 47, and cow's-milk allergy in 11 examinees; eight children were evaluated because of severe systemic reactions following diphtheria-pertussis-tetanus, measles, or inactivated polio (Salk) vaccinations. In one child, there was only a suspicion of general allergy. The undiluted MMR prick test gave negative reactions in 126 cases (93%). The highest rate of nonreactivity was observed in those with atopic eczema (96%) and in children with asthma (91%) or cow's-milk allergy (82%). All examinees with systemic reactions after other vaccinations also had negative prick-test reactions. A total of 122 (95%) of the 129 examinees were eventually vaccinated with MMR. No untoward reactions developed, except mild generalized urticaria or fever in two vaccinees. We conclude that at least 95% of children with common forms of systemic allergy can be vaccinated safely with MMR and, in general, that allergic diseases should not interfere with execution of the vaccination programs.     

Why do parents hesitate to vaccinate their children against measles,mumps and rubella?

Background: Thanks to a successful voluntary vaccination programme, measles, mumps and rubella are rare diseases in Sweden. Coverage among children 18 mo of age has been 99%, but the measles, mumps and rubella vaccination (MMR) has increasingly been questioned among parents. Aim: To study reasons why parents choose not to vaccinate their child against measles, mumps and rubella, and their opinions on vaccines and the diseases themselves. A secondary objective was to compare coverage at 18 mo of age based on parental report with the national statistics based on patient charts. Methods: The official statistics were compared with patient charts for two birth cohorts in the city of Göteborg, Sweden. Out of these children born in 1995 and 1996, 300 unvaccinated and vaccinated children were identified. Their parents received a postal questionnaire assessing the parent's views on vaccines and childhood diseases. Results: The documented vaccine coverage in this study was higher in 1995 and 1996 than official statistics indicated. The major reason, for both groups, for accepting respectively declining vaccination was strengthening the child's immune system. Parents with children unvaccinated against MMR were also more likely to have declined vaccination against diphtheria, polio, tetanus, Haemophilus influenzae and pertussis. One‐third of the parents with a child unvaccinated against MMR had not yet made their final decision 3 y after the vaccine offer. Few parents, both with vaccinated and unvaccinated children, had acquired vaccine information from the Internet. Both groups believed that insufficient time was allocated for vaccine information and discussion at the Child Health Centre. Conclusion: Our study indicates that official statistics on MMR vaccination uptake underestimate the number of vaccinated children. Vaccine safety is a major concern for many parents and needs to be addressed by healthcare professionals at institutions offering paediatric vaccinations.     

Reported pertussis infection and risk of atopy in 8- to 12-yr-old vaccinated and non-vaccinated children.

Pertussis infection has been suspected to be a potential causal factor in the development of atopic disease because of the effect of pertussis immunization on specific IgE antibodies. Although several studies found a positive association between pertussis infection and atopic disorders, this relationship has not yet been studied in a population stratified by vaccination status. To assess the association between pertussis infection and atopic disorders in pertussis-unvaccinated children and in pertussis-vaccinated children. Using data from a previously conducted study on the relationship between the diphtheria-tetanus-pertussis-(inactivated) poliomyelitis vaccination in the first year of life and atopic disorders, the study population of 1872 8-12 yr old was divided into children pertussis-unvaccinated and children pertussis-vaccinated in the first year of life. Within each group, the association between pertussis infection and atopic disorders (both as reported by the parents) was assessed. In the unvaccinated group, there were no significant associations between pertussis infection and atopic disorders. In the vaccinated group, all associations between pertussis infection and atopic disorders were positive, the associations with asthma [odds ratio (OR) = 2.24, 95% confidence interval (CI(95%)): 1.36-3.70], hay fever (OR = 2.35, CI(95%): 1.46-3.77) and food allergy (OR = 2.68, CI(95%): 1.48-4.85) being significant. There was a positive association between pertussis infection and atopic disorders in the pertussis vaccinated group only. From the present study, it cannot be concluded whether this association is causal or due to reverse causation.     

Serological evaluation of 52 children immunized with the combined measles, mumps and rubella vaccine.

Fifty-two of 298 children vaccinated with the measles-mumps-rubella (MMR) vaccine at around the age of 16 months were evaluated for antibody titres against measles, mumps, and rubella. The seropositivity rates for measles, mumps, and rubella were 86%, 92%, and 98%, respectively. While the most prominent side effects were irritability (6.04%) and fever (4.69%), 83.55% of the vaccinated children showed no undesirable reaction to the vaccine. The MMR vaccine appeared to be immunogenic and nonreactogenic for the children in the study.     

Occurrence of acute diarrhea in atopic and nonatopic infants: the role of prolonged breast-feeding.

A cohort of 336 infants was followed from birth for a total of 717 child-years for development of atopy and occurrence of acute diarrhea. During follow-up 94 (28%) of the infants developed atopic eczema or gastrointestinal allergy associated with food allergens, or both. Infants with food allergy had significantly (p = 0.0074) more episodes of acute diarrhea than infants with no atopy, but there was no apparent temporal correlation between the occurrence of acute diarrhea and appearance of gastrointestinal allergy or atopic eczema. Serum IgE levels in children up to 2 years of age who had diarrhea and atopic eczema were lower than those in atopic eczema children with no diarrhea, but infants with gastrointestinal allergy who had acute diarrhea tended to have higher IgE levels than those without diarrhea. Breast-feeding over 6 months of age reduced the incidence of diarrhea in the first year of life in both atopic and nonatopic infants, but had no significant effect on the total incidence of diarrhea during the 2 year follow-up, as infants breast-fed longer had more diarrhea in the second year of life. Prolonged breast-feeding also reduced the severity of diarrhea in atopic infants aged 7-12 months but not for older infants.     

Determinants of atopic sensitization in Turkish school children: Effects of pre- and post-natal events and maternal atopy

Emergence of new environmental risk factors, and/or loss of protective factors of a traditional lifestyle may explain the increase, or variations in prevalence of allergic diseases. The aim of this study was to delineate the prevalence and spectrum of, and to reveal the causal and/or protective factors for atopic sensitization among a heterogenous cohort of Turkish children, for the first time in our country. The study design adhered to International Study of Asthma and Allergies in Childhood (ISAAC) phase II protocol. A self‐administered parental questionnaire about demographic characteristics and detailed risk factors, and skin‐prick test with 13 allergens were employed in a clustered random sample of 8–11‐yr‐old Turkish school children. Atopy was defined as the presence of at least one positive skin reaction to any allergen tested. The association between a total of 78 risk factors and different aspects of atopy were analyzed in 1144 children with multivariate logistic regression analysis. The overall prevalence of atopy was 20.6%. Most common sensitizations were to grass pollens, Dermatophagoides pteronyssinus and Blatella germanica. Day care attendance, high paternal education level, male gender and maternal asthma were significant risk factors for atopy. Breastfeeding more than 6 months (compared with 0–6 months), maternal smoking during pregnancy and a birth weight under 2500 g were inversely related to (or protective factors for) atopic sensitization. Maternal atopic disease had significant effects on risk factors pattern. In children with a maternal atopy history a low birth weight, day care attendance and maternal smoking during the first year of life independently increased the risk of atopic sensitization. Gender, breastfeeding and paternal education did not show any association with atopy in this group of children. A history of measles and low gestational age were significant protective factors for mite sensitization. This study showed that children of atopic mothers showed a different profile of risk factors associated with atopic sensitization, when compared with other children. Prenatal and early childhood events had important associations with atopic sensitization.     

Atopy, eczema and breast milk fatty acids in a high-risk cohort of children followed from birth to 5 yr

BACKGROUND: The incidence of atopic diseases such as eczema is increasing in westernized societies. The suggestion that there is a "protective" association between the unique fatty acid composition of breast milk, particularly the omega-3 (n-3) and omega-6 (n-6) essential polyunsaturated fatty acid content, and the development of atopic disease in children was investigated in a cohort study of 263 infants born into families with a history of allergy (one or both parents had asthma, hayfever, eczema). The objectives of this study were to determine the lipid profile [specifically in relation to long-chain polyunsaturated fatty acid (LC-PUFA) composition] in maternal breast milk samples collected at 6 wk and at 6 months following birth, and to investigate the potential role of these fatty acids in modulating the phenotype of children at high genetic risk of developing atopic disease. METHOD: Breast milk samples were available from 91 atopic mothers at their child's ages of 6 wk and 6 months. These samples were analysed for the fatty acid spectrum. Analysis of variance was used to detect differences between groups of outcomes (no atopy or eczema, non-atopic eczema, atopy, atopic eczema) at ages 6 months and 5 yr, and a multiple comparisons procedure was conducted to isolate the parameters producing the different results (F-test, LSD test). For the exposure variables, n-3 and n-6 fatty acids are expressed as weight percentage and as a ratio (at both time-points). RESULTS: The fatty acid profiles of maternal breast milk at 6 wk and 6 months were similar. An increased ratio of n-6: n-3 fatty acids in both 6 wk and 6 month milk samples was associated with non-atopic eczema (p < 0.005) but not atopy alone or atopic eczema. CONCLUSION: We found milk fatty acids were a significant modulator of non-atopic eczema but not atopy or atopic eczema in infants at 6 months. In mothers with a history of asthma, hayfever or eczema, their 6-month-old infants were more likely to develop non-atopic eczema if their milk had a higher ratio of n-6: n-3 LC-PUFA.     

Diagnostic accuracy of the atopy patch test and the skin-prick test for the diagnosis of food allergy in young children with atopic eczema/dermatitis syndrome

Aim: To evaluate the diagnostic value of the skin-prick test and the atopy patch test in diagnosing basic food allergy in young children suffering from atopic eczema/dermatitis syndrome.

Methods: 141 children, the majority under 2 y of age (mean 16 mo) with atopic eczema/dermatitis syndrome were investigated using skin-prick and atopy patch tests for milk, egg, wheat and rye. Open diagnostic elimination challenge was done since this has been reported to be a reliable method in young children.

Results: A positive challenge response was found to milk in 63 (45%), egg in 78 (55%), wheat in 61 (43%) and rye in 61 (43%). Sensitivity/specificity of the atopy patch test was 60%/97% for milk, 71%/97% for egg, 90%/94% for wheat and 93%/90% for rye. For the skinprick test the corresponding figures were 41%/99%, 60%/97%, 13%/98% and 15%/99%.

Conclusion: Patch testing was found to be a more sensitive method than the skin-prick test in diagnosing food allergy in children with atopic eczema/dermatitis syndrome, especially in those under 2 y of age. Many children with a negative skin-prick test result have a positive patch test result, especially in the case of cereals. A diagnosis of food allergy should be confirmed by elimination and in the research setting also by challenge.     

Two Doses of Measles Mumps Rubella (MMR) Vaccine

A schedule of two doses of measles mumps rubella vaccine (MMR) at an interval of six weeks was tried in children aged between 12 and 48 months. One hundred percent seroconversion was attained in the measles HI (hemagglutinin inhibition) test, rubella HI test, and mumps ELISA test in both groups of children who received NIH (National Institute of Health, Japan) MMR lot B-30 and Kitasato MMR lot TV-1. The possibility of vaccine failure with one dose of measles vaccine is not negligible [1], and the frequency of vaccine failure increases if three vaccines are combined in the form of MMR. Our observations revealed that a few of the children who had received one dose of MMR remained seronegative with regard to measles HI antibody and rubella HI antibody, and that some of the children remained seronegative with regard to mumps ELISA antibody. A schedule of two doses of MMR was shown to be helpful in reinforcing immunity in children who did not respond satisfactorily to one dose of MMR. We concluded that two doses of MMR are preferable to control measles, mumps and rubella infections.     

Increased serum‐soluble interleukin‐5 receptor alpha level precedes the development of eczema in children

Semic‐Jusufagic A, Gevaert P, Bachert C, Murray C, Simpson A, Custovic A. Increased serum‐soluble interleukin‐5 receptor alpha level precedes the development of eczema in children.
Pediatr Allergy Immunol 2010: 21: 1052–1058.
© 2010 John Wiley & Sons A/S Interleukin‐5 receptor α‐subunit expression may be implicated in the development of allergic diseases. In a population‐based birth cohort, we investigated the relationship between IL‐5Rα and the development of allergic phenotypes in childhood, using soluble IL‐5Rα (s‐IL‐5Rα) as a marker. Children (n = 510) were followed from birth and assessed at age 3, 5 and 8. Based on the onset and resolution of symptoms, we assigned children into the following wheeze and eczema phenotypes: never, transient, persistent, intermittent and late‐onset. Specific IgE to common allergens, s‐IL‐5Rα (ELISA) and urinary eosinophilic protein X (U‐EPX) levels was measured at age 5. s‐IL‐5Rα was significantly higher among atopic compared to non‐atopic children (pg/ml, geometric means [95% CI], 152.4 [126.0–184.5] vs. 103.4 [94.0–113.9], p < 0.0001). While we found no association between s‐IL‐5Rα and current eczema at age 5, there was a significant association between eczema phenotypes and s‐IL‐5Rα (multiple anova model adjusted for gender and atopy, F = 2.56, p = 0.04). After adjustment for multiple comparisons, we found that children with late‐onset eczema had significantly higher s‐IL‐5Rα compared to those who have never had eczema (mean difference [95% CI], 2.41 [1.03–5.62], p = 0.04) and those with intermittent eczema (2.63 [1.08–6.41], p = 0.02), with no difference between children who have never had eczema and other eczema phenotypes. We found no such association for wheeze phenotypes. There was a weak correlation between s‐IL‐5Rα and U‐EPX (r = 0.16, p < 0.0001). Increased serum s‐IL‐5Rα level at age 5 was associated with contemporaneous atopic sensitization and with subsequent development of eczema by age 8.     

The epidemiology of subacute sclerosing panencephalitis in England and Wales 1990-2002

Aim: To assess the impact of measles/mumps/rubella (MMR) vaccine on the epidemiology of subacute sclerosing panencephalitis (SSPE) in England and Wales. Methods: Cases of SSPE resident in England and Wales with onset between 1990 and 2002 were reviewed. Results: A total of 47 cases were identified, 31 male and 16 female. There was an average annual decline of 14% in SSPE onset over the period, consistent with the decline in notified measles over the last 20 years. A history of measles was present in 35 (median age 1.3 years), the most recent recorded date being 1994; the interval from measles to onset of SSPE ranged from 2.7 to 23.4 years. Four children with a history of receipt of a measles containing vaccine were reported not to have had measles; two of these cases had a brain biopsy, and nucleotide sequence data confirmed wild measles infection. Brain biopsy specimens from a further three cases with a history of measles, of whom two had also had a history of vaccination, showed wild-type strain. Conclusion: The prevention of endemic circulation of measles virus in England and Wales through the high coverage achieved with MMR vaccine, together with the measles/rubella vaccination campaign of 1994, has resulted in the near elimination of SSPE. However, the recent decline in MMR vaccine coverage, with the associated increase in localised measles outbreaks and cases in young infants, is of concern. It underlines the importance of maintaining high vaccine coverage in order to protect indirectly those most vulnerable to SSPE, namely infants too young to be vaccinated.     

The epidemiology of subacute sclerosing panencephalitis in England and Wales 1990-2002.

AIM: To assess the impact of measles/mumps/rubella (MMR) vaccine on the epidemiology of subacute sclerosing panencephalitis (SSPE) in England and Wales. METHODS: Cases of SSPE resident in England and Wales with onset between 1990 and 2002 were reviewed. RESULTS: A total of 47 cases were identified, 31 male and 16 female. There was an average annual decline of 14% in SSPE onset over the period, consistent with the decline in notified measles over the last 20 years. A history of measles was present in 35 (median age 1.3 years), the most recent recorded date being 1994; the interval from measles to onset of SSPE ranged from 2.7 to 23.4 years. Four children with a history of receipt of a measles containing vaccine were reported not to have had measles; two of these cases had a brain biopsy, and nucleotide sequence data confirmed wild measles infection. Brain biopsy specimens from a further three cases with a history of measles, of whom two had also had a history of vaccination, showed wild-type strain. CONCLUSION: The prevention of endemic circulation of measles virus in England and Wales through the high coverage achieved with MMR vaccine, together with the measles/rubella vaccination campaign of 1994, has resulted in the near elimination of SSPE. However, the recent decline in MMR vaccine coverage, with the associated increase in localised measles outbreaks and cases in young infants, is of concern. It underlines the importance of maintaining high vaccine coverage in order to protect indirectly those most vulnerable to SSPE, namely infants too young to be vaccinated.     

Anaphylactic reactions to measles-mumps-rubella vaccine in three children with allergies to hen's egg and cow's milk

Aim: Allergies to hen’s egg and cow’s milk are the most frequent food allergies in infancy and childhood. Current guidelines recommend safe administration of measles–mumps–rubella (MMR) vaccine in egg allergic patients. Methods: We present three cases of anaphylaxis that we encountered after MMR vaccination in children sensitized to hen’s egg and cow’s milk. Results: Even though MMR vaccine is generally known to be safe in children with egg allergy, there may still be isolated cases of anaphylaxis. Conclusion: Therefore, we recommend that all children not only those who were sensitized to foods should receive the MMR vaccination in a setting that is equipped to deal with anaphylactic reactions. As stated by WHO in immunization safety surveillance, ‘Each vaccinator must have an emergency kit with adrenaline, and be familiar with its dosage and administration’.     

Safety of MMR immunization in egg-allergic children

In Spain, for many years allergy to eggs was considered to contraindicate vaccines cultured in fibroblasts from chick embryos such as the measles, mumps, rubella (MMR) and influenza vaccines. Consequently, an alternative vaccine (Triviraten Berna) incubated in diploid human cells has been systematically administered to children who are allergic to eggs, without questioning tolerance to the standard MMR vaccine. After Biotech Bern Laboratory discontinued the production of Triviraten, this alternative was no longer available for children with egg allergy, who should receive a first dose of the MMR vaccine at the age of 15 months and a second one (booster dose) at the age of 3 years. In this context, from November 2004 to June 2005, a single dose of the MMR vaccine was administered to 40 children with allergy to eggs and none showed an adverse reaction. We conclude that this vaccine can be safely administered to this group of patients.     

Mite allergy, clinical atopy, and restriction by HLA class II immune response genes

From a community-based study cohort of 1812 elementary schoolchildren we selected 129 unrelated participants to investigate the relevance of HLA-class II molecules (DPB, DQB, and DRB) to the regulation of immune response to the mite allergen Der p 1 and to clinical atopic disorders. On the basis of skin prick test results validated by measurement of specific IgE, individuals were selected and divided into three groups: group I (n = 20), controls without detectable specific IgE to common inhalant allergens; group II (n = 22), children sensitized only to non-mite allergens; group III (n = 85), children sensitized to Der p 1. Clinical history of asthma, eczema, and hay fever was ascertained using standardized questionnaires. In total, 43 different HLA class II alleles (DPB, n = 19; DQB, n = 14; and DRB, n = 10) were determined by sequence-specific oligonucleotide typing with PCR-amplified DNA. We were not able to demonstrate significant differences in gene frequencies of any HLA class II allele between the group of mite-sensitized children and one of the other two groups. However, the presence of certain DRB- and DPB-haplotypes (DRB *0100/*0300/*1100 and DPB *0201/*0401) was significantly associated (p < 0.01) with a history of asthma, hay fever, and atopy (defined as a history of asthma and/or hay fever and/or eczema). Other haplotypes, including DQB *0303/*0503, DRB *0200/*0700, and DPB 0402 were negatively associated with a history of eczema, hay fever, and atopy (p < 0.01). Thus, our findings do not suggest a relevance of HLA-class II molecules to mite allergy; however, some HLA class n haplotypes appear to be predictive of the incidence of atopic disorders.     

The association of allergic symptoms with sensitization to inhalant allergens in childhood

Although it is generally agreed that sensitization is an important risk factor for allergic diseases, the extent to which sensitization accounts for allergic symptoms in children is controversial. As part of the Aalst Allergy Study, this cross‐sectional study investigated the prevalence of allergic symptoms and their association with sensitization in an unselected population of Flemish children aged 3.4–14.8 yr. Skin prick testing with the most common aeroallergens was performed and allergic symptoms were documented by a parental questionnaire. In the children older than 6 yr, a significant association of current wheezing, current dyspnea, airway hyperreactivity, rhinoconjunctivitis, and current eczema with sensitization was found, while in the pre‐school children these associations were less pronounced. The association with sensitization was strongest for rhinoconjunctivitis and current respiratory symptoms – the association was less striking for children with current eczema. The impact of a positive family history of allergy on the association with sensitization was more important for eczema than for the other analyzed allergic symptoms. Persistent and late‐onset wheezers were significantly more likely than non‐wheezers and transient early wheezers to be associated with sensitization and a personal history of rhinoconjunctivitis. Late‐onset wheezing was associated with a positive family history of allergy, while transient early wheezing was associated with day‐care attendance. An association with eczema was found for all three childhood wheezing phenotypes. The association of allergic symptoms with sensitization is significant in the older but less pronounced in pre‐school children and is more pronounced for current allergic symptoms. Diagnosis and disease definition of allergy symptoms remains difficult at pre‐school age. The influence of a positive family history of allergy on the association of the respective allergic symptoms with sensitization was most important for eczema. Our data confirm the atopic characteristics of the different wheeze phenotypes.     

Atopy-suggesting symptoms in the first 2 years of life. Effect of gestational age, nutrition and social class

In a prospective study on 318 non-selected infants signs of atopy as well as interrelations with feeding regimens and family history of atopic disease were investigated at the age of 1 1/2 year. The study population was recruited from preterm and term babies hospitalized 1985 in the University Children's Hospital Freiburg, Germany. The most common symptom was eczema. In addition, clinical symptoms of atopy in first degree relatives were a significant risk factor. Because the highest incidence of atopic symptoms occurred in preterm born children with allergic background in their families, we therefore consider this population at highest risk to develop atopic disease. On the other hand there was no significant influence of breast feeding, cow's milk formula and the time of intake of allergenic food on the clinical manifestation of atopy in any group. Although eczema occurred predominantly in infants with higher social level the respiratory tract symptoms were reported more frequently in children from working class families. We therefore regard the social status as an important confounding variable in the studies of risk factors for the development of allergy.     

Association of parental eczema, hayfever, and asthma with atopic dermatitis in infancy: birth cohort study.

OBJECTIVE: To evaluate the association of parental history of atopic disease with childhood atopic dermatitis, and to examine the relative strength of associations with maternal and paternal disease. DESIGN: Mothers were recruited to the Avon longitudinal study of parents and children (ALSPAC) from the eighth week of pregnancy. Before parturition, both parents were asked, separately, to report their lifetime history of eczema, asthma, and hayfever. Parents reported symptoms of atopic dermatitis in their children at ages 6, 18, 30, and 42 months. RESULTS: Of 8530 children with complete information on rash at ages 6, 18, 30, and 42 months, 7969 had complete information on maternal atopic disease and 5658 on maternal and paternal atopic disease. There was a strong association between parental eczema and childhood atopic dermatitis: odds ratio 1.69 (95% confidence interval, 1.47 to 1.95) for maternal eczema only, 1.74 (1.44 to 2.09) for paternal eczema only, and 2.72 (2.09 to 3.53) for eczema in both parents. Associations with parental asthma or hayfever were attenuated after controlling for parental eczema. There was no evidence that associations with maternal atopy were stronger than with paternal. CONCLUSIONS: Associations between parents' atopic disease and the risk of atopic dermatitis in offspring vary according to the type of atopic disease in the parents, but not according to parental sex. These results are at variance with previous studies reporting stronger associations with maternal than paternal atopy, and suggest that there is no "parent-of-origin" effect in atopic dermatitis. Parental eczema may be a better marker than parental asthma/hayfever in predisposing to childhood eczema.     

Association of autistic spectrum disorder and the measles,mumps, and rubella vaccine: a systematic review of current epidemiological evidence

OBJECTIVE: To systematically review the evidence for and against the existence of an association between autistic spectrum disorder (ASD) and the measles, mumps, and rubella (MMR) vaccine.Study DESIGN: We conducted a systematic review of the medical literature to identify all controlled epidemiological articles examining for an association between ASD and the MMR vaccine. We extracted data from the articles on the characteristics and objectives of the study as well as evidence of an association. RESULTS: Twelve articles met the inclusion criteria. One study found no difference in the rates of ASD and the MMR vaccine in children who were vaccinated and those who were not. Six studies examined for evidence of an increase in ASD associated with an increase in the MMR vaccine coverage, none of which showed evidence of an association. Four studies examined if a variant form of ASD was associated with the MMR vaccine, none of which showed evidence of an association. Eight studies attempted to determine if there was a temporal association between developing ASD and receiving the MMR vaccine. Of these, 1 study identified an increase in parental concern in the 6-month period following vaccination with MMR in one of its analyses. The results of all other studies showed no association between ASD and the MMR vaccine. CONCLUSIONS: The current literature does not suggest an association between ASD and the MMR vaccine; however, limited epidemiological evidence exists to rule out a link between a rare variant form of ASD and the MMR vaccine. Given the real risks of not vaccinating and that the risks and existence of variant ASD remain theoretical, current policies should continue to advocate the use of the MMR vaccine.     

经病原学确诊的207例儿童麻疹临床特征分析

目的:对经实验室确诊的麻疹病例进行分析,探讨麻疹疫苗接种对儿童麻疹临床发病特点的影响,以及婴儿麻疹和儿童麻疹发病特点的差异,以帮助麻疹的早期诊断。方法:采集2002至2010年在首都儿科研究所隔离门诊和住院期间经RT-PCR或ELISA法确诊的麻疹患儿临床资料。采用ELISA方法检测麻疹病毒血清特异性IgM抗体,咽拭子和尿液标本采用RT-PCR方法检测麻疹病毒N基因片段。根据是否接种麻疹疫苗分为接种麻疹疫苗组和未接种麻疹疫苗组。结果：①207例经病原学确诊的麻疹患儿进入分析,其中男123例,女84例。年龄0～15岁,其中<8月龄（未达到初免年龄）69例（33.3%）,～1岁45例（21.7%）。未接种麻疹疫苗组154例（≤1岁亚组97例,>1岁亚组57例）,接种麻疹疫苗组53例。②接种麻疹疫苗组本市户籍所占比例显著高于未接种麻疹疫苗组。两组的发病高峰均在4月份。有明确麻疹患者接触史患儿在未接种麻疹疫苗组为15.4%（24/154例）,接种麻疹疫苗组为16.9%（9/53例）,两组差异无统计学意义。③接种麻疹疫苗组麻疹黏膜斑和咳嗽发生率显著低于未接种麻疹疫苗组,余伴随症状两组差异无统计学意义。④未接种麻疹疫苗组>1岁亚组眼部症状发生率高于≤1岁亚组,余临床表现两亚组差异无统计学意义。结论：麻疹发病年龄趋低龄化,同时临床表现更加不典型;麻疹患儿以未达到麻疹疫苗接种年龄的婴儿或漏种麻疹疫苗的流动人口为主,提示加强适龄儿童麻疹疫苗接种和对流动人口易感儿童查漏补种,对降低麻疹发病率有重要意义。