Residual susceptibility to measles among young adults in Victoria,Australia following a national targeted measles-mumps-rubella vaccination campaign

Background  

Past measles immunisation policies in Australia have resulted in a cohort of young adults who have been inadequately vaccinated, but who also have low levels of naturally acquired immunity because immunisation programs have decreased the circulation of wild virus. A measles-mumps-rubella (MMR) immunisation campaign aimed at addressing this susceptibility to measles among young adults was conducted in Australia in 2001–2. By estimating age-specific immunity, we aimed to evaluate the success of this campaign in the state of Victoria.     

Prevalence and factors associated with incomplete immunization of children (12–23 months) in Kwabre East District,Ashanti Region,Ghana

Background

Childhood immunization is one of the most cost effective health interventions but its rate has been declining recently in Ghana. Information on immunization coverage and determinants is needed to improve immunization programmes. The objective of this study was to determine the prevalence and factors associated with incomplete immunization of children (12–23 months) in Kwabre East District, Ghana.

Methods

A cross-sectional, community-based survey involving 322 children and their mothers was carried out. Data were collected on socio-demographic characteristics of mothers, childhood immunization history and mothers’ knowledge and practices of immunization using a structured questionnaire. Children were classified as incompletely immunized if they failed to receive at least one of 8 vaccine doses: - one dose of Bacillus Calmette–Guérin (BCG), 3 doses each of pentavalent, 3 doses of polio and one dose of measles per WHO/UNICEF definition. Chi-square and logistic regression analyses were used to identify the factors associated with incomplete immunisation.

Results

The prevalence of incomplete immunization was low (15.5%) suggesting high immunisation coverage but the coverage of the second measles dose, taken at 18 months of age, was the lowest (23.9%). Most of the mothers knew the importance of immunisation (95.7%) and at least one vaccine-preventable disease or symptom (84.9%). Two factors associated with incomplete immunisation in bivariate analyses (community of residence, and mother’s knowledge of number of oral polio vaccines given to children) were no longer significant in a logistic regression model. Compared to children in Aboaso, children in Gyamfi Wonoo (AOR?=?1.81, 95% CI?=?0.80–4.08), Mamponteng (Bonwunu) (AOR?=?0.59, 95% CI?=?0.24–1.48) and Mamponteng (Town) (AOR?=?0.63, 95% CI?=?0.26–1.55) had similar odds of incomplete immunisation. Similarly, mother’s lack of knowledge of the number of doses of polio vaccine given to children had no effect on the odds of incomplete immunisation (AOR?=?0.53, 95% CI?=?0.22–1.26).

Conclusions

Immunization coverage is high in the Kwabre East district but very few children received the second measles dose. None of the maternal and child factors assessed is associated with immunisation coverage. Further research is needed to identify the determinants of immunisation coverage and the reasons for the low uptake of second measles dose in the study area.

     

Effectiveness assessment of vaccination policy against measles epidemic in Japan using an age–time two-dimensional mathematical model

Objectives  

In 2007, measles prevailed among the youth and young adult population in Japan, creating in a serious social problem. Among the developed countries, Japan has a relatively high incidence of measles. The objective of this study was to assess the effect of improvements in the vaccination policy against measles through simulations.     

Impact of conflict on infant immunisation coverage in Afghanistan: a countrywide study 2000–2003

Background  

Infant immunisation is an effective public health intervention to reduce the morbidity and mortality of vaccine preventable diseases. However, some developing countries fail to achieve desirable vaccination coverage; Afghanistan is one such country. The present study was performed to evaluate the progress and variation in infant immunisation coverage by district and region in Afghanistan and to assess the impact of conflict and resource availability on immunisation coverage.     

The pre-vaccination regional epidemiological landscape of measles in Italy: contact patterns, effort needed for eradication, and comparison with other regions of Europe

Background  

Strong regional heterogeneity and generally sub-optimal rates of measles vaccination in Italy have, to date, hampered attainment of WHO targets for measles elimination, and have generated the need for the new Italian National Measles Elimination Plan. Crucial to success of the plan is the identification of intervention priorities based upon a clear picture of the regional epidemiology of measles derived from the use of data to estimate basic parameters. Previous estimates of measles force of infection for Italy have appeared anomalously low. It has been argued elsewhere that this results from Italian selective under-reporting by age of cases and that the true measles force of infection in Italy is probably similar to that of other European countries. A deeper examination of the evidence for this conjecture is undertaken in the present paper.     

Cost-benefit analyses of supplementary measles immunisation in the highly immunized population of New Zealand

As endemic measles is eliminated from countries through increased immunisation, the economic benefits of enhanced immunisation programs may come into question. New Zealand has suffered from outbreaks after measles introductions from abroad and we use it as a model system to understand the benefits of catch up immunisation in highly immunised populations. We provide cost-benefit analyses for measles supplementary immunisation in New Zealand. We model outbreaks based on estimates of the basic reproduction number in the vaccinated population (R_v, the number of secondary infections in a partially immunised population), based on the number of immunologically-naïve people at district and national levels, considering both pre- and post-catch up vaccination scenarios. Our analyses suggest that measles R_v often includes or exceeds one (0.18–3.92) despite high levels of population immunity. We calculate the cost of the first 187 confirmed and probable measles cases in 2014 to be over NZ$1 million (∼US$864,200) due to earnings lost, case management and hospitalization costs. The benefit-cost ratio analyses suggest additional vaccination beyond routine childhood immunisation is economically efficient. Supplemental vaccination-related costs are required to exceed approximately US$66 to US$1877 per person, depending on different scenarios, before supplemental vaccination is economically inefficient. Thus, our analysis suggests additional immunisation beyond childhood programs to target naïve individuals is economically beneficial even when childhood immunisation rates are high.     

Measles vaccine coverage and factors related to uncompleted vaccination among 18-month-old and 36-month-old children in Kyoto,Japan

Background  

Due to low vaccine coverage, Japan has not only experienced outbreaks of measles but has also been exporting it overseas. This study aims to survey measles vaccine coverage and the factors uncompleted vaccination among community-living children.     

Pattern and determinants of BCG immunisation delays in a sub-Saharan African community

Background  

Childhood immunisation is recognised worldwide as an essential component of health systems and an indispensable indicator of quality of care for vaccine-preventable diseases. While performance of immunisation programmes is more commonly measured by coverage, ensuring that every child is immunised at the earliest/appropriate age is an important public health goal. This study therefore set out to determine the pattern and predictors of Bacille de Calmette-Guérin (BCG) immunisation delays in the first three months of life in a Sub-Saharan African community where BCG is scheduled at birth in order to facilitate necessary changes in current policy and practices for improved services.     

Following in the footsteps of smallpox: can we achieve the global eradication of measles?

Background  

Although an effective measles vaccine has been available for almost 40 years, in 2000 there were about 30 million measles infections worldwide and 777,000 measles-related deaths. The history of smallpox suggests that achieving measles eradication depends on several factors; the biological characteristics of the organism; vaccine technology; surveillance and laboratory identification; effective delivery of vaccination programmes and international commitment to eradication.     

An outbreak of measles in a highly immunised population: immunisation status and vaccine efficacy

Abstract: An outbreak of 18 cases of measles in a primary school in the Australian Capital Territory in August and September 1993 provided the opportunity to study measles immunisation status and measles vaccine efficacy. Parents of 384 (78 per cent) of 491 children answered a questionnaire on recent illness consistent with measles and measles immunisation. Parents transcribed details of measles immunisation from the personal health record of the child to the questionnaire. Thirty-three per cent of cases and 3.4 per cent of the other children had not been immunised. Overall, 95 per cent of children had been immunised. The efficacy for all measles vaccines was estimated to be 90 per cent (95 per cent confidence interval (CI) 75 to 96) and for measles-mumps vaccine 87 per cent (CI 70 to 95). All of the immunised cases had received measles-mumps vaccine. There was no increased risk of measles infection in those who had been immunised at under 15 months of age compared with those immunised at 15 months or older, or in those who could not provide a date of immunisation compared with those who could. None of the children who had received two doses of vaccine caught measles. The date of immunisation was provided by 65 per cent of the respondents who said their children had been immunised. Asking parents to provide this date instead of viewing the health record is a less expensive way of assessing immunisation status but this method needs to be evaluated. Measles outbreaks still occur in highly immunised populations when vaccine efficacy appears to be acceptable.     

The cost of measles in industrialised countries

The aim of this study is to estimate the costs of measles and measles control in 11 industrialised countries with varying levels of measles vaccine coverage. Country-specific annual incidence of measles, measles immunization policy, coverage and costs data were collected. The average societal costs of measles cases and immunisation programme per capita were calculated. These 11 countries spend together over US$ 151 million every year to treat and control measles. Per capita costs of measles control tend to be higher in countries with poorer measles control programmes (for instance, Italy has the highest incidence and highest overall costs), though many other factors, such as the number of antigens given per clinic visit and the local price of MMR also affect the efficiency of the programme. The costs estimates presented here can be used to estimate potential savings that might accrue from changes to measles control programmes.     

Assessment of measles immunity among infants in Maputo City,Mozambique

Background  

The optimum age for measles vaccination varies from country to country and thus a standardized vaccination schedule is controversial. While the increase in measles vaccination coverage has produced significant changes in the epidemiology of infection, vaccination schedules have not been adjusted. Instead, measures to cut wild-type virus transmission through mass vaccination campaigns have been instituted. This study estimates the presence of measles antibodies among six- and nine-month-old children and assesses the current vaccination seroconversion by using a non invasive method in Maputo City, Mozambique.     

Progress towards measles elimination in Singapore

ObjectiveWe describe the epidemiological trends of measles in Singapore in relation to its progress towards measles elimination and identify gaps in fulfilling the World Health Organization Western Pacific Regional Office regional measles elimination criteria.MethodsEpidemiological data on measles maintained by the Communicable Diseases Division, Ministry of Health from 1981 to 2012 were collated and analysed. Data on measles vaccination coverage were obtained from the National Immunization Registry and School Health Services, Health Promotion Board. To assess the seroprevalence of the population, the findings of periodic seroepidemiological surveys on measles were traced and reviewed.FindingsWith the successful implementation of the National Childhood Immunization Programme using the monovalent measles vaccine, measles incidence declined from 88.5 cases per 100,000 in 1984 to 6.9 per 100,000 in 1991. Resurgences were observed in 1992, 1993 and 1997. A ‘catch-up’ vaccination programme using the trivalent measles, mumps and rubella (MMR) vaccine was conducted in 1997, followed by introduction of the two-dose vaccination schedule in January 1998. Measles incidence subsequently declined sharply to 2.9 per 100,000 in 1998. Vaccination coverage was maintained at 95% for the first dose and 92–94% for the second dose. Seroprevalence surveys showed seropositivity for measles IgG antibodies in over 95% of adults in 2004, and in 83.1% of children aged 1–17 years in 2008–2010. Sporadic cases with occasional clusters of two or more cases continued to occur among the unvaccinated population, especially children aged below 4 years. The predominant measles virus genotype has shifted from D9 to the B3 and G3 genotypes, which are endemic in neighbouring countries.ConclusionSingapore has made good progress towards the elimination of endemic measles. To further eliminate sporadic cases of measles, the national immunisation schedule has recently been amended to vaccinate children with 2 doses of MMR vaccine before 2 years of age.     

Why children are not vaccinated against measles: a cross-sectional study in two Nigerian States

Background

Childhood vaccination rates in Nigeria are among the lowest in the world and this affects morbidity and mortality rates. A 2011 mixed methods study in two states in Nigeria examined coverage of measles vaccination and reasons for not vaccinating children.

Methods

A household survey covered a stratified random cluster sample of 180 enumeration areas in Bauchi and Cross River States. Cluster-adjusted bivariate and then multivariate analysis examined associations between measles vaccination and potential determinants among children aged 12-23 months, including household socio-economic status, parental knowledge and attitudes about vaccination, and access to vaccination services. Focus groups of parents in the same sites subsequently discussed the survey findings and gave reasons for non-vaccination. A knowledge to action strategy shared findings with stakeholders, including state government, local governments and communities, to stimulate evidence-based actions to increase vaccination rates.

Results

Interviewers collected data on 2,836 children aged 12-23 months in Cross River and 2,421 children in Bauchi. Mothers reported 81.8% of children in Cross River and 42.0% in Bauchi had received measles vaccine. In both states, children were more likely to receive measles vaccine if their mothers thought immunisation worthwhile, if immunisation was discussed in the home, if their mothers had more education, and if they had a birth certificate. In Bauchi, maternal awareness about immunization, mothers’ involvement in deciding about immunization, and fathers’ education increased the chances of vaccination. In Cross River, children from communities with a government immunisation facility were more likely to have received measles vaccine. Focus groups revealed lack of knowledge and negative attitudes about vaccination, and complaints about having to pay for vaccination. Health planners in both states used the findings to support efforts to increase vaccination rates.

Conclusion

Measles vaccination remains sub-optimal, particularly in Bauchi. Efforts to counter negative perceptions about vaccination and to ensure vaccinations are actually provided free may help to increase vaccination rates. Parents need to be made aware that vaccination should be free, including for children without a birth certificate, and vaccination could be an opportunity for issuing birth certificates. The study provides pointers for state level planning to increase vaccination rates.

     

Human resources for health and burden of disease: an econometric approach

Background  

The effect of health workers on health has been proven to be important for various health outcomes (e.g. mortality, coverage of immunisation or skilled birth attendants). The study aim of this paper is to assess the relationship between health workers and disability-adjusted life years (DALYs), which represents a much broader concept of health outcome, including not only mortality but also morbidity.     

Absence of endemic measles transmission in a highly vaccinated population from 1999 to 2008: Implications of sustained measles elimination in Taiwan

Background

Measles remains a leading vaccine-preventable cause of child mortality worldwide. The impact of vaccination programs can be seen in the increasingly low incidence of measles. However, cases of measles continue to occur in low numbers every year in Taiwan. We assessed the epidemiology of measles in Taiwan from 1999 to 2008 with a focus on domestic versus imported cases.

Methods

We analyzed the data reported to surveillance systems at the Taiwan Center for Disease Control, where viral isolation was performed.

Results

A total of 84 measles cases were reported from 1999 to 2008 in Taiwan with the incidence of measles varying from 0 to 1.5 per 1,000,000 people per year, peaking in 2002 and again in 2008. The incidence decreased with increasing age in both males and females. Among the 84 reported measles cases, 39 (46%) originated internationally, 8 (10%) were epidemiologically linked to imported cases and the source was unknown in 37 (44%) of the cases. The unknown-source cases were analyzed for potential evidence of endemic measles transmission. Most of the measles cases that occurred in Taiwan from 1999 to 2008 were associated with imported cases. No endemic transmission of measles in Taiwan was identified.

Conclusions

This study suggests that maintaining the high rate of vaccination coverage is needed to prevent future outbreak and sustain the elimination of measles in Taiwan.     

The potential for measles transmission in England

Background  

Since the schools vaccination campaign in 1994, measles has been eliminated from England. Maintaining elimination requires low susceptibility levels to keep the effective reproduction number R below 1. Since 1995, however, MMR coverage in two year old children has decreased by more than 10%.     

Attitudes towards 12-step groups and referral practices in a 12-step naive treatment culture; a survey of addiction professionals in Norway

Background  

Addressing substance use disorders effectively requires a long-term approach. Substance abuse treatment is typically of short duration; referring patients to Twelve Step based self-help groups (TSGs) – e.g. Narcotics Anonymous, represents a promising complementary recovery resource. Clinicians' attitudes and referral practices towards the TSGs have mainly been studied in countries with high integration of the 12-step philosophy in their substance abuse services and where the TSGs are widely available, such as the US. In Norway, there are currently 294 weekly TSG meetings (6 per 100,000 inhabitants). This study describes clinicians' attitudes and referral practices to TSGs in Norway where health authorities seek to promote self-help participation, but where the treatment culture is unfamiliar with 12-step fellowships.