Factors affecting uptake of measles, mumps, and rubella immunisation

Factors affecting non-coverage of measles-rubella vaccination among children aged 9-59 months in Tanzania

Globally, measles remains a major cause of child mortality, and rubella is the leading cause of birth defects among all infectious diseases. In 2012, the World Health Assembly endorsed the Global Vaccine Action Plan that set a target to eliminate Measles-Rubella (MR) in five of the six World Health Organization (WHO) regions by 2020. This was cross-sectional study employed both quantitative and qualitative research methods. The sample size was calculated to provide overall, age- and sex-specific coverage estimates for MR vaccine among children aged between 9 and 59 months at the national level. Using desired precision of ±5% with an expected coverage of 95%, a total of 15,235 households were required. The age of children, a child who had received the MR vaccine before the campaign, household wealth quintile, the age of caregivers, and their marital status were associated with non-coverage of MR vaccination among children aged 9-59 months in Tanzania. Nationally, an estimated 88.2% (95% CI: 87.3-89%) of children aged 9-59 months received the MR campaign dose, as assessed by caregivers' recall. These estimates revealed slightly higher coverage in Zanzibar 89.6% (95% CI: 84.7-93%) compared to Mainland Tanzania 88.1% (95% CI 87.2-88.9%). These associated factors revealed causes of unvaccinated children and may be some of the reasons for Tanzania's failure to meet the MR campaign target of 95 percent vaccination coverage. Thus, vaccine development must increase programmatic oversight in order to improve immunization activities and communication strategies in Tanzanian areas with low MR coverage.

Psychological Factors Associated with the Uptake of Measles Immunization

A cross-sectional study of 8204 children was performed to investigate the prevalence of immunization against measles, mumps and rubella and possible determinants of immunization uptake. The study was approached from a Lewinian perspective on preventive behaviour. Seventy-one questions referring to the guardian of the child, his or her partner, the household and the child, as well as to immunization-related experiences and situational topics were asked. Two psychological variables were studied: health locus of control and subjective relevance concerning measles. The immunization rate was 77.7 percent [95 percent confidence interval 76.8-78.6]. Multiple logistic regression yielded the following odds ratios for non- uptake of measles immunization: natural health orientation 8.74 [6.72-11.37]; advice of paediatrician 6.02 [4.67-7.75]; dangerousness of measles 2.00 [1.53-2.60]; marital status 1.87 [1.31-2.51]; assessed reliability of vaccination 1.57 [1.23-2.01]; smoking 1.55 [1.21-1.98]; and number of siblings 1.55 [1.21- 1.98]. Parents or guardians of immunized children were more internal and assessed measles as more relevant than those of non- immunized children.

Family Characteristics Associated with Likelihood of Varicella Vaccination

CONTEXT

The introduction of the varicella vaccine as a routine pediatric immunization in the US, in 1995, provided an opportunity to assess factors associated with uptake of new vaccines in the member population of the Kaiser Permanente Northwest (KPNW) Health Plan.

OBJECTIVE

Identify factors associated with varicella vaccination in the KPNW population in the first five years after varicella vaccine was introduced.

DESIGN

A retrospective cohort of children under age 13 years between June 1995 and December 1999, without a history of varicella disease was identified using KPNW automated data. Membership records were linked to vaccine databases. Cox regression was used to estimate likelihood of varicella vaccination during the study period in relation to age, sex, primary clinician's specialty, and Medicaid eligibility. For a subset whose parents answered a behavioral health survey, additional demographic and behavioral characteristics were evaluated.

MAIN OUTCOME MEASURE

Varicella vaccination.

RESULTS

We identified 88,646 children under age 13 years without a history of varicella; 22% were vaccinated during the study period. Varicella vaccination was more likely among children who were born after 1995, were not Medicaid recipients, or had pediatricians as primary clinicians. In the survey-linked cohort, positively associated family characteristics included smaller family size; higher socioeconomic status; and parents who were older, were college graduates, reported excellent health, and received influenza vaccination.

CONCLUSION

Understanding predictors of early varicella vaccine-era vaccine acceptance may help in planning for introduction of new vaccines to routine schedules.

Does frequent residential mobility in early years affect the uptake and timeliness of routine immunisations? An anonymised cohort study

BACKGROUND

There are conflicting findings regarding the impact of residential mobility on immunisation status. Our aim was to determine whether there was any association between residential mobility and take up of immunisations and whether they were delayed in administration.

METHODS

We carried out a cohort analysis of children born in Wales, UK. Uptake and time of immunisation were collected electronically. We defined frequent movers as those who had moved: 2 or more times in the period prior to the final scheduled on-time date (4 months) for 5 in 1 vaccinations; and 3 or more times in the period prior to the final scheduled on-time date (12 months) for MMR, pneumococcal and meningitis C vaccinations. We defined immunisations due at 2-4 months delayed if they had not been given by age 1; and those due at 12-13 months as delayed if they had not been given by age 2.

RESULTS

Uptake rates of routine immunisations and whether they were given within the specified timeframe were high for both groups. There was no increased risk (odds ratios (95% confidence intervals) between frequent movers compared to non-movers for the uptake of: primary MMR 1.08 (0.88-1.32); booster Meningitis C 1.65 (0.93-2.92); booster pneumococcal 1.60 (0.59-4.31); primary 5 in 1 1.28 (0.92-1.78); and timeliness: primary MMR 0.92 (0.79-1.07); booster Meningitis C 1.26 (0.77-2.07); booster pneumococcal 1.69 (0.23-12.14); and primary 5 in 1 1.04 (0.88-1.23).

DISCUSSION

Findings suggest that children who move home frequently are not adversely affected in terms of the uptake of immunisations and whether they were given within a specified timeframe. Both were high and may reflect proactive behaviour in the primary healthcare setting to meet Government coverage rates for immunisation.

Effect of socioeconomic deprivation on uptake of measles, mumps and rubella vaccination in Liverpool, UK over 16 years: a longitudinal ecological study

Suboptimal uptake of the measles, mumps and rubella (MMR) vaccine by certain socioeconomic groups may have contributed to recent large measles outbreaks in the UK. We investigated whether socioeconomic deprivation was associated with MMR vaccine uptake over 16 years. Using immunization data for 72,351 children born between 1995 and 2012 in Liverpool, UK, we examined trends in vaccination uptake. Generalized linear models were constructed to examine the relative effect of socioeconomic deprivation and year of birth on MMR uptake. Uptake of MMR1 by age 24 months ranged between 82·5% in 2003 [95% confidence interval (CI) 81·2-83·7] and 93·4% in 2012 (95% CI 92·7-94·2). Uptake of MMR2 by age 60 months ranged between 65·3% (95% CI 64·4-67·4) in 2006 and 90·3% (95% CI 89·4-91·2) in 2012. In analysis adjusted for year of birth and sex, children in the most deprived communities were at significantly greater risk of not receiving MMR1 [risk ratio (RR) 1·70, 95% CI 1·45-1·99] and MMR2 (RR 1·36, 95% CI 1·22-1·52). Higher unemployment and lower household income were significantly associated with low uptake. Contrary to concerns about lower MMR uptake in affluent families, over 16 years, children from the most socioeconomically deprived communities have consistently had the lowest MMR uptake. Targeted catch-up campaigns and strategies to improve routine immunization uptake in deprived areas are needed to minimize the risk of future measles outbreaks.

The impact of the media on the decision of parents in South Wales to accept measles-mumps-rubella (MMR) immunization

A large measles outbreak occurred in South Wales in 2012/2013. The outbreak has been attributed to low take-up of measles-mumps-rubella (MMR) immunization in the early 2000s. To understand better the factors that led to this outbreak we present the findings of a case-control study carried out in the outbreak area in 2001 to investigate parents' decision on whether to accept MMR. Parents who decided not to take-up MMR at the time were more likely to be older and better educated, more likely to report being influenced by newspapers [adjusted odds ratio (aOR) 3·07, 95% confidence interval (CI) 1·62-5·80], television (aOR 3·30, 95% CI 1·70-6·43), the internet (aOR 7·23, 3·26-16·06) and vaccine pressure groups (aOR 5·20, 95% CI 2·22-12·16), and less likely to be influenced by a health visitor (aOR 0·30, 95% CI 0·16-0·57). In this area of Wales, daily English-language regional newspapers, UK news programmes and the internet appeared to have a powerful negative influence. We consider the relevance of these findings to the epidemiology of the outbreak and the subsequent public health response.

Is there an association between the coverage of immunisation boosters by the age of 5 and deprivation? An ecological study

OBJECTIVE

To determine whether there was an association between the coverage of booster immunisation of Diphtheria, Tetanus, acellular Pertussis and Polio (DTaP/IPV) and second Measles, Mumps and Rubella (MMR) dose by age 5 in accordance with the English national immunisation schedule by area-level socioeconomic deprivation and whether this changed between 2007/08 and 2010/11.

DESIGN

Ecological study.

DATA

Routinely collected national Cover of Vaccination Evaluated Rapidly data on immunisation coverage for DTaP/IPV booster and second MMR dose by age 5 and the Index of Multiple Deprivation (IMD).

SETTING

Primary Care Trust (PCT) areas in England between 2007/08 and 2010/11.

OUTCOME MEASURES

Population coverage (%) of DTaP/IPV booster and second MMR immunisation by age 5.

RESULTS

Over the 4 years among the 9,457,600 children there was an increase in the mean proportion of children being immunised for DTaP/IPV booster and second MMR across England, increasing from 79% (standard deviation (SD12%)) to 86% (SD8%) for DTaP/IPV and 75% (SD10%) to 84% (SD6%) for second MMR between 2007/08 and 2010/11. In 2007/08 the area with lowest DTaP/IPV booster coverage was 31% compared to 54.4% in 2010/11 and for the second MMR in 2007/08 was 39% compared to 64.8% in 2010/11. A weak negative correlation was observed between average IMD score and immunisation coverage for the DTaP/IPV booster which reduced but remained statistically significant over the study period (r=-0.298, p<0.001 in 2007/08 and r=-0.179, p=0.028 in 2010/11). This was similar for the second MMR in 2007/08 (r=-0.225, p=0.008) and 2008/09 (r=-0.216, p=0.008) but there was no statistically significant correlation in 2009/10 (r=-0.108, p=0.186) or 2010/11 (r=-0.078, p=0.343).

CONCLUSION

Lower immunisation coverage of DTaP/IPV booster and second MMR dose was associated with higher area-level socioeconomic deprivation, although this inequality reduced between 2007/08 and 2010/11 as proportions of children being immunised increased at PCT level, particularly for the most deprived areas. However, coverage is still below the World Health Organisation recommended 95% threshold for Europe.

Factors associated with poor adherence to MMR vaccination in parents who follow vaccination schedule

Due to median vaccination coverage far from elimination level, Italy is still an European country with high number of measles cases per million of people. In this study we explored potential socioeconomic, medical and demographic factors which could influence the propensity of family members for measles vaccination schedule. A cross-sectional study was performed through a questionnaire administered to the parents of children who received the first dose of MMR vaccine in two different vaccination centers in the Palermo area from November 2012 to May 2013. Overall, the role played by internet (OR 19.8 P = 0.001) and the large number of children in a family (OR 7.3 P ≤ 0.001) were the factors more associated to be unvaccinated, whereas the birth order of the child (OR 0.3 P = < 0.05 for the oldest children vs. the closer young one) and reporting a lack of MMR vaccination as a "personal decision" (OR 0.19 P ≤ 0.01) inversely correlated with the risk of quitting vaccination. These findings can be useful for a better knowledge of disaffection to vaccination practice in local settings and could contribute to improve and maintain timely uptake, suggesting approaches to optimize the uptake of MMR tailored to the needs of local populations.

Parental concern about vaccine safety in Canadian children partially immunized at age 2: a multivariable model including system level factors

Children who begin but do not fully complete the recommended series of childhood vaccines by 2 y of age are a much larger group than those who receive no vaccines. While parents who refuse all vaccines typically express concern about vaccine safety, it is critical to determine what influences parents of ‘partially’ immunized children. This case-control study examined whether parental concern about vaccine safety was responsible for partial immunization, and whether other personal or system-level factors played an important role. A random sample of parents of partially and completely immunized 2 y old children were selected from a Canadian regional immunization registry and completed a postal survey assessing various personal and system-level factors. Unadjusted odds ratios (OR) and adjusted ORs (aOR) were calculated with logistic regression. While vaccine safety concern was associated with partial immunization (OR 7.338, 95% CI 4.138– 13.012), other variables were more strongly associated and reduced the strength of the relationship between concern and partial immunization in multivariable analysis (aOR 2.829, 95% CI 1.151 – 6.957). Other important factors included perceived disease susceptibility and severity (aOR 4.629, 95% CI 2.017 – 10.625), residential mobility (aOR 3.908, 95% CI 2.075 – 7.358), daycare use (aOR 0.310, 95% CI 0.144 - 0.671), number of needles administered at each visit (aOR 7.734, 95% CI 2.598 – 23.025) and access to a regular physician (aOR 0.219, 95% CI 0.057 – 0.846). While concern about vaccine safety may be addressed through educational strategies, this study suggests that additional program and policy-level strategies may positively impact immunization uptake.

Biosocial correlates of inter-generational social mobility in a British cohort

The relationship between inter-generational social mobility of sons and daughters between 1958 and 1991 and biosocial variables, i.e. birth order, number of children in family, father's social class, region, educational attainment of child and father, educational and cognitive test scores (reading, mathematics, verbal and non-verbal IQ tests), was studied in a large British cohort study. The data used were collected as part of the British National Child Development Study (NCDS). The extent of social class mobility was determined inter-generationally and was categorized as none (no change in social class between the father's and index child's social class), upwardly mobile (where the index child moved up one or more social classes compared with their father) or downwardly mobile (where the index child moved down one or more social classes compared with their father). All of the biosocial variables were associated with social mobility when analysed separately. Multivariate analyses revealed that the most significant predictor of mobility categories in both sexes was education of the cohort member, followed by social class of the father. In both sexes mathematics score was a significant predicator, while in sons reading and non-verbal IQ scores were also important predictors. In the light of these results, it appears that social mobility in Britain takes place largely on meritocratic principles.

Characteristics of 5-year-olds who catch-up with MMR: findings from the UK Millennium Cohort Study

OBJECTIVES

To examine predictors of partial and full measles, mumps and rubella (MMR) vaccination catch-up between 3 and 5 years.

DESIGN

Secondary data analysis of the nationally representative Millennium Cohort Study (MCS).

SETTING

Children born in the UK, 2000-2002.

PARTICIPANTS

751 MCS children who were unimmunised against MMR at age 3, with immunisation information at age 5.

MAIN OUTCOME MEASURES

Catch-up status: unimmunised (received no MMR), partial catch-up (received one MMR) or full catch-up (received two MMRs).

RESULTS

At age 5, 60.3% (n=440) children remained unvaccinated, 16.1% (n=127) had partially and 23.6% (n=184) had fully caught-up. Children from families who did not speak English at home were five times as likely to partially catch-up than children living in homes where only English was spoken (risk ratio 4.68 (95% CI 3.63 to 6.03)). Full catch-up was also significantly more likely in those did not speak English at home (adjusted risk ratio 1.90 (1.08 to 3.32)). In addition, those from Pakistan/Bangladesh (2.40 (1.38 to 4.18)) or 'other' ethnicities (such as Chinese) (1.88 (1.08 to 3.29)) were more likely to fully catch-up than White British. Those living in socially rented (1.86 (1.34 to 2.56)) or 'Other' (2.52 (1.23 to 5.18)) accommodations were more likely to fully catch-up than home owners, and families were more likely to catch-up if they lived outside London (1.95 (1.32 to 2.89)). Full catch-up was less likely if parents reported medical reasons (0.43 (0.25 to 0.74)), a conscious decision (0.33 (0.23 to 0.48)), or 'other' reasons (0.46 (0.29 to 0.73)) for not immunising at age 3 (compared with 'practical' reasons).

CONCLUSIONS

Parents who partially or fully catch-up with MMR experience practical barriers and tend to come from disadvantaged or ethnic minority groups. Families who continue to reject MMR tend to have more advantaged backgrounds and make a conscious decision to not immunise early on. Health professionals should consider these findings in light of the characteristics of their local populations.

Socio-demographic factors associated with treatment against soil-transmitted helminth infections in children aged 12-59 months using the health facility approach alone or combined with a community-directed approach in a rural area of Zambia

A health facility-based (HF) approach to delivering anthelminthic drugs to children aged 12-59 months in Zambia was compared with an approach where community-directed treatment (ComDT) was added to the HF approach (HF+ComDT). This paper reports on the socio-demographic factors associated with treatment coverage in the HF+ComDT and HF areas after 18 months of implementation. Data were collected by interviewing 288 and 378 caretakers of children aged 12-59 months in the HF+ComDT and HF areas, respectively. Bivariate and multivariate logistic regression analyses were used for data analysis. Statistically significant predictors of a child being treated were: a child coming from the HF+ComDT area, being 12-36 months old, the family having lived in the area for >20 years, coming from a household with only one under-five child and living ≤3 km from the health facility. It is concluded that socio-demographic factors are of public health relevance and affect treatment coverage in both the HF+ComDT and the HF approaches. The implementation and strengthening of interventions like ComDT that bring treatment closer to households will enable more children to have access to treatment.

Making sense of perceptions of risk of diseases and vaccinations: a qualitative study combining models of health beliefs, decision-making and risk perception

Background

Maintaining high levels of childhood vaccinations is important for public health. Success requires better understanding of parents' perceptions of diseases and consequent decisions about vaccinations, however few studies have considered this from the theoretical perspectives of risk perception and decision-making under uncertainty. The aim of this study was to examine the utility of subjective risk perception and decision-making theories to provide a better understanding of the differences between immunisers' and non-immunisers' health beliefs and behaviours.

Methods

In a qualitative study we conducted semi-structured in-depth interviews with 45 Australian parents exploring their experiences and perceptions of disease severity and susceptibility. Using scenarios about 'a new strain of flu' we explored how risk information was interpreted.

Results

We found that concepts of dread, unfamiliarity, and uncontrollability from the subjective perception of risk and ambiguity, optimistic control and omission bias from explanatory theories of decision-making under uncertainty were useful in understanding why immunisers, incomplete immunisers and non-immunisers interpreted severity and susceptibility to diseases and vaccine risk differently. Immunisers dreaded unfamiliar diseases whilst non-immunisers dreaded unknown, long term side effects of vaccines. Participants believed that the risks of diseases and complications from diseases are not equally spread throughout the community, therefore, when listening to reports of epidemics, it is not the number of people who are affected but the familiarity or unfamiliarity of the disease and the characteristics of those who have had the disease that prompts them to take preventive action. Almost all believed they themselves would not be at serious risk of the 'new strain of flu' but were less willing to take risks with their children's health.

Conclusion

This study has found that health messages about the risks of disease which are communicated as though there is equality of risk in the population may be unproductive as these messages are perceived as unbelievable or irrelevant. The findings from this study have implications beyond the issue of childhood vaccinations as we grapple with communicating risks of new epidemics, and indeed may usefully contribute to the current debate especially in the UK of how these theories of risk and decision-making can be used to 'nudge' other health behaviours.

[Risk factors for delayed or missed measles vaccination in young children]

Because of low measles vaccine coverage rates, measles outbreaks have been observed several times during recent years in Germany. The aim of this study is to identify parents' attitudes and beliefs towards immunisations and socio-economic factors which are associated with delayed or missed first measles vaccination in young children. We used data from a representative German-wide immunisation survey on 2116 children born between 1 January 2002 and December 2004 by collecting precise vaccination information from vaccination cards. The influence of socio-economic determinants and parental attitudes towards immunisations on the timing of the first measles dose was analysed by using multivariable Cox regression. Of these children 46.8% (95% CI: 44.5-49.1) received their first measles dose according to the recommendations of the standing committee on vaccination (STIKO) by month 15. In multivariable analysis, fathers aged 28-33 years and birth order as well as parents' belief in homeopathy and other parental attitudes indicating lack of knowledge about the importance of vaccinations significantly influenced an early immunisation. Not general opposition, but insufficient parental knowledge about the harmfulness of measles infection seemed to be responsible for the low measles vaccination rates.

Immunisation attitudes, knowledge and practices of health professionals in regional NSW

OBJECTIVE

This study investigated the immunisation knowledge, attitudes and practices among health professionals in two regional Area Health Services of NSW with low and high immunisation rates. It also compared these factors between the areas and between the health professional groups.

METHODS

A self-administered questionnaire was posted in 2006 to health professionals, located within the North Coast and Hunter New England Area Health Services, whose practice could include immunisation. This included general practitioners (GPs), practice nurses, community nurses, hospital nurses and midwives.

RESULTS

Out of 926 surveys sent, 434 were returned (47%). The great majority of the health professionals (97%) believed that vaccines were safe, effective and necessary. However, in approximately one-third of respondents, there were specific concerns about additives, immune system overload and the number of vaccines. Significantly more health professionals in the North Coast area believed that additives in vaccines may be harmful and that adding more vaccines to the schedule would make immunisation too complex. Among GPs, over half felt uncomfortable about giving more than two injections at the one visit.

CONCLUSIONS

Health professionals in this study had overall confidence in vaccines but had specific concerns about the number of vaccines given to children and vaccine content. These unfounded concerns may reduce parental confidence in immunisation.

IMPLICATIONS

There is value in governments and immunisation support workers continuing their efforts to maintain up-to-date knowledge among health professionals and support the delivery of appropriate and targeted information to address concerns about vaccines.

Sibling configuration and childhood growth in contemporary British families

BACKGROUND

Life history theory and resource dilution models of the family suggest that siblings may present a threat to healthy development because they compete for resources that parents have available to invest in individual offspring. Using data from a large cohort study of contemporary British families (ALSPAC), we test this hypothesis using childhood growth trajectories as a biomarker for health status.

METHODS

Incorporating time-varying measures of changing family structure and socio-economic environment, this study represents the first true longitudinal analysis of family configuration effects on human growth. Using separate multi-variate multi-level models we estimate the effect of sibling number and sibling age and sex on height from birth to 10 years.

RESULTS

Adjusting for family level socio-economic factors, the presence of siblings is associated with deficits in height across the study period. At the largest comparison, we estimate that compared with only children, children with four siblings have a reduced birth length by -8.7 mm (95% confidence interval (CI): -14.8 to -2.6) and a reduced rate of growth by -2.3 mm per year (95% CI: -3.8 to -0.8), leading to a deficit of 31.5 mm by age 10. Older siblings are associated with larger lasting negative consequences on height than younger siblings. We find no difference in the height of children in relation to the sex of siblings.

CONCLUSIONS

Even in the relatively wealthy, well-nourished conditions of modern Western society, children are not buffered from the health costs of reduced parental investment. Later-born children appear worst affected by within family resource division.

Factors associated with uptake of measles, mumps, and rubella vaccine (MMR) and use of single antigen vaccines in a contemporary UK cohort: prospective cohort study

OBJECTIVES

To estimate uptake of the combined measles, mumps, and rubella vaccine (MMR) and single antigen vaccines and explore factors associated with uptake and reasons for not using MMR.

DESIGN

Nationally representative cohort study.

SETTING

Children born in the UK, 2000-2.

PARTICIPANTS

14,578 children for whom data on immunisation were available.

MAIN OUTCOME MEASURES

Immunisation status at 3 years defined as "immunised with MMR," "immunised with at least one single antigen vaccine," and "unimmunised."

RESULTS

88.6% (13,013) were immunised with MMR and 5.2% (634) had received at least one single antigen vaccine. Children were more likely to be unimmunised if they lived in a household with other children (risk ratio 1.74, 95% confidence interval 1.35 to 2.25, for those living with three or more) or a lone parent (1.31, 1.07 to 1.60) or if their mother was under 20 (1.41, 1.08 to 1.85) or over 34 at cohort child's birth (reaching 2.34, 1.20 to 3.23, for > or =40), more highly educated (1.41, 1.05 to 1.89, for a degree), not employed (1.43, 1.12 to 1.82), or self employed (1.71, 1.18 to 2.47). Use of single vaccines increased with household income (reaching 2.98, 2.05 to 4.32, for incomes of > or = 52,000 pounds sterling (69,750 euros, $102,190)), maternal age (reaching 3.04, 2.05 to 4.50, for > or =40), and education (reaching 3.15, 1.78 to 5.58, for a degree). Children were less likely to have received single vaccines if they lived with other children (reaching 0.14, 0.07 to 0.29, for three or more), had mothers who were Indian (0.50, 0.25 to 0.99), Pakistani or Bangladeshi (0.13, 0.04 to 0.39), or black (0.31, 0.14 to 0.64), or aged under 25 (reaching 0.14, 0.05 to 0.36, for 14-19). Nearly three quarters (74.4%, 1110) of parents who did not immunise with MMR made a "conscious decision" not to immunise.

CONCLUSIONS

Although MMR uptake in this cohort is high, a substantial proportion of children remain susceptible to avoidable infection, largely because parents consciously decide not to immunise. Social differentials in uptake could be used to inform targeted interventions to promote uptake.

Factors associated with a measles outbreak in children admitted at Mahosot Hospital, Vientiane, Laos

BACKGROUND

In 2002 and 2003 there were large outbreaks of measles in many provinces of Laos, including in Vientiane. We therefore conducted a study to determine risk factors associated with measles amongst children admitted at Mahosot Hospital, Vientiane.

METHODS

A retrospective case-control study was conducted in 50 children with clinical measles who were matched by age and sex with 50 healthy children (who had never had a febrile rash) living in the same villages as the cases.

RESULTS

The proportion of children with complete immunizations was significantly lower in the group with clinical measles compared to the controls [13/50 (26%) vs 34/50 (68%), P < 0.001). The percentage of children who had received measles vaccine at 9-23 months of age was significantly lower in the group with clinical measles compared to the healthy controls [12/50 (24%) vs 24/50 (48%), P = 0.01). The family educational and socio-economic status did not differ significantly (P > 0.05) between cases and controls.

CONCLUSION

These results emphasize the importance of intensification of measles immunization coverage in Laos. The strengthening of campaigns with large, widespread high second dose coverage is likely to be a key measure to prevent further measles outbreaks in Laos (192 words).

Impact of adverse publicity on MMR vaccine uptake: a population based analysis of vaccine uptake records for one million children, born 1987-2004

AIMS

To determine the impact of adverse publicity on MMR uptake and measles susceptibility, including whether vaccination is delayed and the role of deprivation.

METHODS

A population database for all Scotland containing immunisation records for over one million children (n = 1,079,327) born 1987-2004 was analysed. MMR uptake was determined by birth cohort and deprivation category. "Final" uptake (at approx age 6 years) was predicted by linear regression by birth cohort. Measles susceptibility in 1998 and 2003 was determined by postcode sector and district for cohorts combined to construct nursery and primary school age groups.

RESULTS

There is evidence of a slight rise in late uptake, but insufficient to compensate for underlying declines. Late vaccination continues to be associated with deprivation, while the most affluent tend to be vaccinated promptly, or not at all. Predicted figures for "final" MMR1 uptake are over 90%, but under 95%. Measles susceptibility has increased significantly in nursery children, with an eightfold rise in the number of districts with greater than 20% susceptibility in this group (from 3 to 25).

CONCLUSIONS

Increased measles susceptibility in nursery children is concerning, particularly in the most vulnerable areas. These figures are likely to increase in the future, as MMR uptake has not yet returned to the previous higher level. Increased susceptibility levels can also be expected in primary schools in the future, as levels of late uptake are insufficient to compensate. Predicted figures for "final" MMR1 uptake are under the herd immunity threshold and campaigns may be required to increase uptake among future primary school children.

Does qualitative synthesis of anecdotal evidence with that from scientific research help in understanding public health issues: a review of low MMR uptake

STUDY OBJECTIVE

To explore the professional and parental factors underlying low MMR uptake by qualitative synthesis of evidence from technical and non-technical anecdotal literature.

METHODS

An intensive investigation of literature covering research, press, online, E groups and grey literature was carried out using devised search strategies. Key themes were identified from both the research and anecdotal evidence, which were merged to form common themes.

RESULTS

The review of technical literature identified media scare and inadequate information from health professionals as the main reasons for non-uptake of MMR. The non-technical anecdotal evidence showed that professionals' belief in parental right to choose, target payments and fear of autism were the major factors.

CONCLUSIONS

Anecdotal evidence may contribute to evidence-based public health practice, especially in widely debated public health issues.

Immunization rates and timely administration in pre-school and school-aged children

Whereas immunization coverage has been repeatedly assessed in the Swiss population, little is known about the timely administration of universally recommended immunizations in Switzerland and elsewhere. The goal of this study was to determine compliance with official standard immunization recommendations in pre-school and school-aged children in Basel, Switzerland, focusing on coverage rates and timely administration. Of a cohort of children entering kindergarten and third-grade primary school in Basel in 2001, 310 and 310, respectively, were identified in proportion to the overall age-appropriate populations in the four city districts. Foreign-born children were excluded. The data were extracted from immunization records provided voluntarily by parents. Coverage for three doses of diphtheria, tetanus, and poliomyelitis vaccines was >95% and <90% for pertussis and Hib. The rates of age-appropriate booster doses were significantly lower, especially for pertussis and Hib (<60%). Cumulative coverage for measles, mumps, and rubella (MMR) was <90% for the first dose and 33% for the second dose by 10 years of age. All immunizations were administered with significant delays. Coverage for the first three doses of DTP combination vaccines did not reach 90% before 1 year of age and, for the first dose of MMR, a plateau just below 80% was not reached before 3 years of age. Delayed administration of immunizations in childhood, as well as complete lack of booster doses in a significant fraction of children, with important implications for public health have been discovered in this study. This may lead to fatal disease in individuals, epidemics in the community, and threatens national and international targets of disease elimination, such as measles and congenital rubella syndrome.

Vaccination and allergic disease: a birth cohort study

OBJECTIVES

We examined the effect of vaccination for diphtheria; polio; pertussis and tetanus; or measles, mumps, and rubella on the incidence of physician-diagnosed asthma and eczema.

METHODS

We used a previously established birth cohort in the West Midlands General Practice research database.

RESULTS

We found an association between vaccination and the development of allergic disease; however, this association was present only among children with the fewest physician visits and can be explained by this factor.

CONCLUSIONS

Our data suggest that currently recommended routine vaccinations are not a risk factor for asthma or eczema.

University students immunized and not immunized for measles: a comparison of beliefs, attitudes, and perceived barriers and benefits

OBJECTIVE

To compare students who were immunized or not immunized during the 1997 Simon Fraser University measles outbreak in British Columbia.

METHODS

Descriptive comparative study using the Health Belief Model as a theoretical framework. A self-administered questionnaire was mailed to a stratified random sample of 400 immunized and 400 non-immunized SFU students.

RESULTS

Perceived susceptibility, severity, barriers, cues to action, threat and student age were significantly related to being immunized. Logistic regression analysis achieved an overall correct prediction rate of 84.7% by including the contribution of the four variables of susceptibility, barriers, cues to action, and health motivation. Content analysis of the non-immunized students' descriptions of what it would have taken for them to be immunized indicated the influence of these four variables.

DISCUSSION

The Immunization Health Belief Model Scale is a valuable tool for ascertaining attitudes and beliefs relating to immunization decision-making. Interventions targeted to significant beliefs may increase immunization coverage levels and result in improved disease prevention.

University students immunized and not immunized for measles: a comparison of beliefs, attitudes, and perceived barriers and benefits

OBJECTIVE

To compare students who were immunized or not immunized during the 1997 Simon Fraser University measles outbreak in British Columbia.

METHODS

Descriptive comparative study using the Health Belief Model as a theoretical framework. A self-administered questionnaire was mailed to a stratified random sample of 400 immunized and 400 non-immunized SFU students.

RESULTS

Perceived susceptibility, severity, barriers, cues to action, threat and student age were significantly related to being immunized. Logistic regression analysis achieved an overall correct prediction rate of 84.7% by including the contribution of the four variables of susceptibility, barriers, cues to action, and health motivation. Content analysis of the non-immunized students' descriptions of what it would have taken for them to be immunized indicated the influence of these four variables.

DISCUSSION

The Immunization Health Belief Model Scale is a valuable tool for ascertaining attitudes and beliefs relating to immunization decision-making. Interventions targeted to significant beliefs may increase immunization coverage levels and result in improved disease prevention.

Parental investment: how an equity motive can produce inequality

The equity heuristic is a decision rule specifying that parents should attempt to subdivide resources more or less equally among their children. This investment rule coincides with the prescription from optimality models in economics and biology in cases in which expected future return for each offspring is equal. In this article, the authors present a counterintuitive implication of the equity heuristic: Whereas an equity motive produces a fair distribution at any given point in time, it yields a cumulative distribution of investments that is unequal. The authors test this analytical observation against evidence reported in studies exploring parental investment and show how the equity heuristic can provide an explanation of why the literature reports a diversity of birth order effects with respect to parental resource allocation.

Low immunisation uptake: is the process the problem?

OBJECTIVE

To examine mothers' satisfaction with the process of immunisation and its possible contribution to suboptimal immunisation uptake.

DESIGN

In depth interviews with mothers.

SETTING

Two Community Care Areas, Dublin city, Ireland.

PARTICIPANTS

In depth interviews of 23 mothers of children 1-2 years old, recruited purposively from a birth cohort born in 1994.

MAIN RESULTS

Mothers preferred general practice to Health Centre immunisation (11:5) for predominantly emotional compared with practical reasons (4:1). Health Centre immunisation was seen, at times, as unacceptably rough and inhuman. Many mothers experienced severe emotional distress at the prospect of inflicting the pain of immunisation on their babies. The non-empathic stance of some immunising doctors was unacceptable to mothers. They valued attempts by health professionals to acknowledge the pain of immunisation and to engage with their baby. Adverse experiences contributed to deferral of future visits and to defaulting behaviour.

CONCLUSIONS

Low empathy mass immunisation in clinic type settings may be unacceptable to mothers in the 1990s, and may in part explain suboptimal uptake in health care systems that use such clinics.

Opportunistic immunisation in hospital

AIM

To assess the potential for administering catch up and scheduled immunisations during hospital admission.

METHODS

Immunisation status according to the child's principal carer was checked against official records for 1000 consecutively admitted preschool age children. Junior doctors were instructed to offer appropriate vaccination before discharge, and consultants were asked to reinforce this proactive policy on ward rounds.

RESULTS

Excluding those children who were not fully immunised against pertussis through parental choice, 142 children (14.2%) had missed an age appropriate immunisation and 41 were due a scheduled immunisation. None had a valid contraindication. Only 43 children were offered vaccination on the ward but uptake was 65% in this group.

CONCLUSIONS

Admission to hospital provides opportunities for catch up and routine immunisations and can contribute to the health care of an often disadvantaged group of children. These opportunities are frequently missed. Junior doctors must be encouraged to see opportunistic immunisation as an important part of their routine work.

Immunisation uptake, services required and government incentives for users of formal day care

OBJECTIVES

To determine immunisation uptake in children attending formal day care prior to the introduction of certificates (state) and parent incentives (federal), and to document parent and child carers' attitudes to these strategies.

METHOD

In 1997, 60 child care centres and 300 family day carers in suburban Melbourne were randomly sampled. Immunisation dates, service use and preference, and views on government incentives were obtained from parents of children under three years of age.

RESULTS

From 2,454 eligible children, information was obtained for 1,779, of whom 84% (95% CI 82-86) were completely immunised. Low income (OR 1.8, 95% CI 1.2-1.9, p < or = 0.001) and larger family size (OR 1.8, 95% CI 1.2-2.7, p = 0.002) and only ever using a doctor (OR 1.6, 95% CI 1.1-2.3) was associated with incomplete immunisation. Main reasons for delaying immunisation were occurrence of minor illness and work commitments. Families would prefer immunisation services at Maternal and Child Health visits (39%), evening sessions (22%) and at day care (22%). Immunisation uptake could increase to 94% if those receiving Childcare Assistance (67%) immunised their children on time but would increase to 87% if these incentive only motivated those for whom Childcare Assistance was essential (15%). While 98% of day care co-ordinators and 71% of family day care co-ordinators documented immunisation status at commencement of child care, only 51% and 33% respectively regularly updated this information.

CONCLUSION

Providing client-focused, flexible immunisation services and government incentives and legislation may work together to boost immunisation levels for those in formal child care.

Immunisation coverage at a well-baby clinic in the United Arab Emirates

The United Arab Emirates Survey of Immunisation Coverage by UNICEF in 1990 showed that the coverage for UAE infants up to one year of age was 60%. The objective of this study was to determine factors associated with attendance and immunisation uptake at a well-baby clinic. A birth cohort of 665 infants were selected and their records examined to determine the factors such as gender, distance of housing area from clinic and access to other primary health care facilities. Only 22% attended all the scheduled visits and 54.3% of the sample completed the immunisation program within the correct time. The distance the infant lived from the clinic was the only factor significantly affecting immunisation uptake. The identification and targeting of groups at high risk of delayed completion of the immunisation program is a necessary risk factor in improving future surveillance.

A retrospective cohort study of risk factors for missing preschool booster immunisation

AIM

To identify factors associated with non-uptake of preschool booster immunisation.

DESIGN

Data from the computerised child health system was used to study all children born in 1990 and living in South Glamorgan, Wales, on their 5th birthday. Factors associated with preschool booster uptake were investigated using multiple logistic regression.

RESULTS

Preschool booster coverage in the study cohort was 91.4%. After adjustment for other variables, uptake was associated most strongly with completed primary immunisation for diphtheria, tetanus, and polio vaccine or first dose measles, mumps, and rubella vaccine. Identifying children who miss either of these predicts 52.4% of those who miss the preschool booster.

CONCLUSION

Effective targeting of children who have missed previous immunisations could improve preschool booster uptake and ensure maximum uptake of at least one dose of measles, mumps, and rubella vaccine. Achieving optimum measles vaccine coverage is vital to achieve the goal of measles elimination.

Vaccine preventable diseases and immunisations: a qualitative study of mothers' perceptions of severity, susceptibility, benefits and barriers

This study investigated mothers' perceptions of vaccine-preventable diseases and associated vaccines in terms of perceived susceptibility, severity, benefits and barriers. A purposive sampling strategy was used to choose mothers whose only or youngest child was completely, incompletely (behind the recommended immunisation schedule) or partially (parents chose or advised not to have a specific immunisation) immunised or had no immunisations. Semi-structured interviews found that complete immunisers believed the risk of vaccines was lower than the risk from disease and that the likelihood of contracting many of these diseases was low. Incomplete immunisers perceived vaccines to be less effective in preventing disease and were often confused about which diseases the vaccines would protect against. Non-immunisers were more concerned about unknown, long-term side effects of vaccines than the diseases. Many mothers who did immunise believed that preventing diseases was not always possible and for diseases such as measles, mumps and rubella, it was not always necessary nor desirable. Vaccines were perceived as placing stress on the immune system rather than strengthening it. Important themes relating to barriers to the decision to immunise were a lack of 'balanced', detailed information and poor communication between health providers and parents. The major barrier to timely, age-appropriate immunisations was the occurrence of minor illnesses in the target child or the family. This study found that many mothers were balancing the risks of immunising with the risks of not immunising and this must be taken into account, along with factors such as difficulties in obtaining immunisations.

Home vaccination for children behind in their immunisation schedule: a randomised controlled trial

OBJECTIVE

To ascertain the effectiveness of a home vaccination service for children behind in their vaccination schedule.

DESIGN

Randomised controlled trial of nurse-administered vaccination at home. Children were allocated at random to the intervention or the control group before any contact with the parents was made.

SETTING

10 council areas in north-west metropolitan Melbourne defined by 56 postcode zones. Six-week intervention period from November 1996.

PARTICIPANTS

405 children--all those in the study area (n = 2610) 90 days late (age 9 months) for their third diphtheria-tetanus-pertussis/poliomyelitis/Haemophilus influenzae type B (DTP/OPV/Hib) vaccination, or 120 days late (age 16 months) for their measles-mumps-rubella (MMR) vaccination, according to the Australia Childhood Immunisation Register.

MAIN OUTCOME MEASURES

Number of children completing DTP/OPV/Hib or MMR during the intervention period, and number up to date before intervention.

RESULTS

Verification of vaccination status with the parents revealed that 123 (60%) of the children in the intervention group and 113 (56%) of those in the control group were up to date with their vaccinations, leaving a study population of 81 (intervention group) and 88 (control group). Vaccination was achieved in 46 (57%) intervention children and 24 (27%) control children (risk ratio [RR], 2.08; 95% CI, 1.4-3.1; P < 0.001). For DTP/OPV/Hib, 18/32 (56%) intervention children and 12/36 (33%) control children were vaccinated, (P = 0.06). For MMR, 28/49 (57%) and 12/52 (23%) children were vaccinated, respectively (P < 0.001). Home vaccinations were completed with 26 families (including five siblings). The average cost per child vaccinated as a result of the home program was $92.52.

CONCLUSION

Home vaccination for children behind in their immunisation schedule is an effective, acceptable and relatively cheap method of completing recommended vaccinations. We recommend that a home vaccination program be widely implemented and made available, particularly for disadvantaged families.

An attempt to swindle nature: press anti-immunisation reportage 1993-1997

There is some evidence that low childhood immunisation rates in Australia may be attributed partly to parental antipathy toward immunisation. The anti-immunisation movement is becoming more organised in its efforts to lobby against childhood immunisation, while the lessening of the public's exposure to the effects of vaccine-preventable disease has provided a climate ripe for such a lobby to have a disproportionate influence on parents. Forty months of Australian print media coverage of immunisation were reviewed for anti-immunisation arguments and their underlying ideological subtexts. Of 2440 articles about childhood immunisation, 115 (4.7 per cent) contained statements opposing immunisation. Eight subtexts that referenced wider discourses about medicine, the state and the body dominated anti-immunisation discourse (cover-up; excavation of the facts; unholy alliance for profit; towards totalitarianism; us and them; vaccines as poisonous chemical cocktails; vaccines as cause of idiopathic ills; and back to nature). Attempts to redress claims made against immunisation must not only address specific claims about vaccine efficacy and safety but be grounded in a reframing of the ideological appeals that currently frame the contents of anti-immunisation discourse.

[Measles, mumps and rubella vaccination status of school beginners in Munich]

A cross-sectional study was performed on all of 10029 school-beginners in Munich in 1994 to investigate the vaccination status of measles, mumps and rubella immunisation. The objective of the study was to determine socio-demographic and psychological factors affecting the MMR vaccination rate. Data were received from 81.8% of all 10029 school-beginners. The vaccination rate was 86.1% for measles, 84.5% for mumps and 72.9% for rubella (missing values not included). Low overall vaccination rate was found in not first-born children, children of parents with non-german nationality, in children of parents with a low socio-economic status, in children accompanied by a working parent, and in children accompanied by a smoking parent. Children without any denomination also showed a lower vaccination rate. Girls had a higher vaccination rate for rubella than boys. A higher overall vaccination rate for MMR was associated with parents considering these infections to have a high impact for people's health. Vice versa children of parents considering adverse effects of vaccination against MMR as an important impact on health had significant lower vaccination rate. The results of a multiple logistic regression model showed two factors significantly affecting the MMR vaccination rate: Physician's recommendation and individual attitude towards medicine seem to have the most important influence on decision making for or against vaccination. In conclusion MMR vaccination strategies have to be improved. New ways such as, no vaccination--no school's should be considered for Germany.

Reasons for non-uptake of measles, mumps, and rubella catch up immunisation in a measles epidemic and side effects of the vaccine

OBJECTIVE

To investigate the reasons for poor uptake of immunisation (non-immunisation) and the possible side effects of measles, mumps, and rubella vaccine in a catch up immunisation campaign during a community outbreak of measles.

DESIGN

Descriptive study of reasons for non-immunisation and retrospective cohort study of side effects of the vaccine.

SETTING

Secondary schools in South Glamorgan.

SUBJECTS

Random cluster sample of the parents of 500 children targeted but not immunised and a randomised sample of 2866 of the children targeted.

MAIN OUTCOME MEASURES

Reasons for non-immunisation; symptoms among immunised and non-immunised children.

RESULTS

Immunisation coverage of the campaign was only 43.4% (7633/17,595). The practical problems experienced included non-return of consent forms (6698/17,595), refusal of immunisation (2061/10,897 forms returned), and absence from school on day of immunisation (1203/8836 children with consent for immunisation). The most common reasons cited for non-immunisation were previous measles infection (145/232), previous immunisation against measles (78/232), and concern about side effects (55/232). Symptoms were equally common among immunised and non-immunised subjects. However, significantly more immunised boys than non-immunised boys reported fever (relative risk 2.31 (95% confidence interval 1.36 to 3.93)), rash (2.00 (1.10 to 3.64), joint symptoms (1.58; 1.05 to 2.38), and headache (1.31 (1.04 to 1.65)).

CONCLUSIONS

Many of the objections raised by parents could be overcome by emphasising that primary immunisation does not necessarily confer immunity and that diagnosis of measles is unreliable. Measles, mumps, and rubella vaccine is safe in children aged 11-15.