Dose Measles Vaccination Research Articles

Progress with the Second Dose Measles Vaccine Introduction and Coverage in the WHO African Region.

To achieve global and regional measles elimination objectives, the World Health Organization (WHO) recommends coverage of 95% or higher with two doses of measles-containing vaccine. A second dose of measles-containing vaccine (MCV) is typically administered in the second year of life after 12 months of age. We reviewed WHO-UNICEF estimates of national coverage (WUENIC) for the first and second doses of MCV (MCV1 and MCV2, respectively) and calculated drop-out rates between MCV1 and MCV2 for countries in the WHO African Region. From 2013 to 2023, estimated regional MCV2 coverage increased from 7% to 49%, and at the end of 2023, 43 (91%) countries had introduced MCV2 into their routine immunization programs. Countries with more antigens provided in the second year of life had higher mean and median MCV2 coverage levels, and lower drop-out rates between MCV1 and MCV2, as compared to countries providing only MCV2. Despite substantial progress, MCV2 coverage remains below the required levels to achieve and sustain elimination, and many countries have high drop-out rates between MCV1 and MCV2 coverage, indicating challenges in reaching children over 12 months of age. Increasing coverage of MCV2 and other vaccines in the second year of life is essential to achieving higher and equitable routine immunization coverage. This will require continued efforts to understand and mitigate barriers to reaching children after 12 months of age and accelerated implementation of available tools.

Tracking Measles and Rubella Elimination Progress-World Health Organization African Region, 2022-2023.

Measles or rubella elimination is verified when endemic transmission of the corresponding virus has been absent for over 36 months in a defined area, in the presence of a well-performing surveillance system. This report updates the progress by 47 countries in the WHO African Region towards the goal of attaining verification of measles and rubella elimination in at least 80% of the countries of the region by 2030. We reviewed the WHO-UNICEF vaccination coverage estimates for the first and second doses of measles- and measles-rubella-containing vaccines, as well as the available coverage data for measles supplementary immunization activities, during 2022-2023. We also reviewed the measles-surveillance performance and analyzed the epidemiological trends of measles and rubella as reported in the case-based surveillance database. The WHO-UNICEF estimates of first measles vaccine dose (MCV1) and second measles vaccine dose (MCV2) coverage for the African Region for 2022 were 69% and 45%, respectively. Rubella-containing vaccines have been introduced in the routine immunization program in 32 of 47 (68%) countries as of the end of 2022, with no introductions during 2023. In 2022 and 2023, a total of 144,767,764 children were vaccinated in the region with measles or MR vaccines in 24 countries through 32 mass vaccination campaigns. The administrative coverage target of 95% was reached in only 15 (49%) of the 32 vaccination campaigns. In 2023, a total of 125,957 suspected cases of measles were reported through the case-based surveillance system, and 73,625 cases (58%) were confirmed to be measles, either by laboratory testing, by epidemiological linkage, or based on clinical compatibility. A total of 4805 confirmed rubella cases were reported, though this total represents substantial under-ascertainment. The regional incidence of measles was 60.3 cases per million population. Twenty-six countries (55%) met the targets for the two principal surveillance system performance-monitoring indicators. No country in the region has attained the verification of measles or rubella elimination as of the end of 2023. Addressing systemic problems with routine immunization and using tailored approaches to reach unvaccinated children can contribute to progress towards measles and rubella elimination. In addition, periodic and timely high-quality preventive SIAs remain a critical programmatic strategy to reach unvaccinated children.

Decadal analysis of measles epidemiological data in India (2011–2020)

BackgroundDespite India being one of the largest contributors to the measles burden, crucial epidemiological information is significantly lacking. We have analyzed the national-level representative data between 2011 and 2020 to estimate the national- and state-level incidence, first dose vaccine coverage, and mortality; and developed a prediction model to examine the trend of the disease.MethodsWe extracted the Health Management Information System (HMIS) for monthly aggregated measles cases, deaths, and child immunization (9–11 months) for first dose measles vaccine coverage across all states & Union Territories (UT). Population information & projections were extracted based on Census 2011. A multilevel fixed effect panel data model was used to predict measles incidence rate, assuming measles vaccination coverage as a predictor while accounting for time fixed effects.ResultsTotal 558,536 measles cases and 4209 measles deaths were reported in India between 2010 and 2020. The incidence rate was highest in 2013 (628.8/million population), followed by a significant decline to reach 52.0/million in 2020. Measles vaccination coverage for the first dose was 84.1% in 2011 to 91.3% in 2019. Higher vaccination coverage was significantly correlated (r = 0.7, p = 0.02) with decline of measles incidence rate. The case fatality rate (CFR) was least in 2014 (0.13%) but upsurged consistently reaching to 3.3% in 2020. The predictive model indicates that with a first-dose vaccine coverage of 93.5%, and keeping other factors constant, the national measles incidence is projected to reach zero by 2025.ConclusionMeasles incidence is declining in India due to higher vaccination coverage, yet the rise in death rates emphasizes the need for continued collaborative efforts to achieve a measles-free nation.

Predictors for low coverage of uptake of second dose of measles vaccine among children in sub-Saharan Africa, 2023: a systematic review and meta-analysis.

Measles became a public health important disease in sub-Saharan Africa. World Health Organization recommended measles-containing vaccine dose 2 (MCV2) through routine service delivery. This study aims to determine coverage of second-dose measles vaccination uptake and its predictors among children aged 24-35 months in sub-Saharan Africa. We conducted an extensive search of literature as indicated in the guideline of reporting systematic review and meta-analysis (PRISMA). The databases used were PubMed, Google Scholar, and HINARI literature. The overall uptake of the second dose of measles vaccine uptake was 41% (95% CI: 28.90-53.47). Caregiver's awareness of the importance of the second dose of measles (2.51, 95% CI 1.77, 3.25), educational status of mothers (1.30, 95% CI 1.16, 1.45), distance from vaccination site (1.22, 95% CI 1.12, 1.32), and attending four and above ANC visit (2.72, 95% CI 2.29, 3.15) were determinants for second dose measles vaccine uptake. Coverage of the second dose of measles uptake in Sub-Saharan Africa was low (41%) which is lower than the recommendation from WHO. Therefore policymakers and stakeholders should increase mother's awareness. Also, special strategies should be developed for those who are far from the vaccination site. ANC: Ante Natal Care; JBI: Joanna Briggs Institute; MCV1: Measles containing vaccine dose 1; MCV2: Measles containing vaccine dose 2; WHO: World Health Organization.

Factors Contributing to the Acceptability of Second Dose of Measles Vaccine among Children in Livingstone District, Zambia

Introduction: Measles is a viral disease that is a major public health problem in both developed and developing countries. It is a contagious disease resulting from infection with the measles virus and is still responsible for more than 100,000 deaths per year. Although vaccination is one of the most successful and cost-effective public health interventions to reduce mortality and morbidity, approximately 1.4 million children worldwide die from vaccine-preventable diseases each year. In Zambia, MCV2 was 66% below WHO recommended target of 95%. This study therefore assessed the acceptability of second dose measles vaccination services among caretakers/mothers with children less than two years of age in Livingstone, Zambia. Methods: The study used analytical cross-sectional study design. A logistic regression analysis was performed to identify factors associated with acceptability of the second dose of measles vaccine. A semi structured questionnaire was administered to collect data on socio demographic characteristics and factors related to acceptability of the second dose of measles vaccine. SPSS version 26.0 was used for descriptive and inferential analysis at 5% level of significance. Results: There was no statistically significant difference in acceptability of the second dose of measles vaccine by gender, marital status, type of employment, income level, socio-cultural and traditional beliefs, and education level. However, there was a statistically significant difference in acceptability of the second dose of measles vaccine by knowledge level of second dose of measles vaccine. A Chi square test result indicated that second dose acceptability was higher with less children than that of respondents with many children (χ2(5) = 15.3, p and knowledge levels (χ2(2) = 14.8, p Changes in knowledge level from medium to high reduced the odds of second dose measles vaccine acceptability. Furthermore, this study showed that acceptance of the second measles vaccination increased from mothers/caretakers with low knowledge (3.6%) to medium knowledge (13.3%) and finally high knowledge (83.1%). Conclusion: Tailored messaging to increase knowledge among mothers and caregivers on the importance of the second dose of measles vaccine is critical in improving acceptability. Therefore, the researchers recommend that the health providers should continue to raise awareness associated with the low acceptability of the second dose of measles vaccine and improve on child preventable diseases such as measles.

Second Dose Measles Vaccination Utilization and Associated Factors in Jabitehnan District, Northwest Ethiopia.

Herd immunity against measles is essential to interrupt measles transmission, and this can only be attained by reaching at least 95% coverage for each of the 2 doses of measles vaccine provided in infancy and early childhood age group. It is important to provide everyone with 2 doses of the measles vaccine in order to effectively safeguard the population. Despite this, little is known about the second dosage of the measles vaccine utilization status and the factors that affect it. Therefore, this study aimed to assess second dose of measles vaccination utilization and its associated factors among children aged 24-35 months in Jabitehnan district, 2020. A community-based cross-sectional study design was conducted at Jabitehnan District, Northwest Ethiopia, from September 1st, 2020 to October 1st, 2020. Systematic random sampling technique was used to select 845 mothers/caregivers who had children aged 24-35 months. Both bi-variable and multivariable logistic regression was fitted to identify the determinant factors of second dose measles vaccination utilization. Finally, the statistical significant variables were declared by using 95% CI and P value less than .05 in the multivariable logistic regression analysis. The Hosmer and Lemeshow test was used to check the model's fit to the data, and the variance inflation factor was used to assess multi-collinearity. The overall second dose of measles vaccination utilization was 48.1%, (95% CI: 44.7-51.6). Mothers with primary school education (AOR = 1.91, 95% CI: 1.15-3.17), information about MCV2 (AOR = 6.53, 95% CI: 4.22-10.08), distance from vaccination site (AOR = 3.56, 95% CI: 2.46-5.14), knowledge about immunization (AOR = 1.935, 95% CI: 1.29-2.90), and favorable attitude about immunization (AOR = 5.19, 95% CI: 3.25-8.29) were significantly associated factors with second dose of measles vaccination utilization. Second dose measles vaccination utilization in the district was lower than the national target. Maternal education, distances from vaccination site, information about MCV2, and knowledge about immunization were significantly associated variables with second dose measles vaccination utilization. Therefore, in order to increase the utilization of the second dose of the measles vaccine, improved health education and service expansion to difficult-to-reach areas are required.

Epidemiological characteristics of a protracted and widespread measles outbreak in the Democratic Republic of Congo, 2018 - 2020.

measles is a highly contagious viral disease. Since 2011, the Democratic Republic of Congo (DR Congo) has had the first dose measles vaccination coverage of less than 80% according to the World Health Organization - United Nations International Children's Emergency Fund (WHO-UNICEF) coverage estimates, and measles mass vaccination coverage of less than the required coverage level of 95% by survey. Starting in August 2018, the country experienced an increase in measles case reports which continued through to early 2020. Epidemiological aspects of the outbreak are described in this article. we analysed aggregate weekly passive surveillance data from the DR Congo for the years 2018 - 2020 to understand the trends of occurrence of suspected measles cases. We also analysed the measles case-based surveillance database to understand the epidemiological characteristics of confirmed cases of measles and rubella during the same period of time. a total of 458,156 suspected measles cases and 8,127 deaths were reported between 1st January 2018 and 31st December 2020, with the majority of cases and deaths reported in 2019. Only 2.9% of these cases were reported through the case-based surveillance system, with 31,639 cases being confirmed as measles by the laboratory, by epidemiological linkage and on clinical compatibility. Children less than 5 years of age were most affected with a cumulative incidence of 960 cases per 1,000,000 inhabitants. Only 41% of the confirmed cases were vaccinated. Maindombe and Tshopo provinces had the highest cumulative incidence levels. There was a distinct geographic progression of the outbreak between provinces during the course of the three years. A total of 1760 lab confirmed rubella cases were confirmed in various provinces among the cases investigated with blood specimens, 93% of whom were less than 15 years of age. the recent gaps in vaccination coverage, the age pattern of confirmed cases and the lack of vaccination history in the majority of cases is suggestive of failure to vaccinate as the likely cause of this large and protracted outbreak. Efforts to improve vaccination coverage and the measles surveillance system are needed in order to prevent the occurrence of future outbreaks and to avert measles-related deaths.

Cost-effectiveness analysis on measles transmission with vaccination and treatment intervention

<abstract><p>A deterministic model which describes measles' dynamic using newborns and adults first and second dose of vaccination and medical treatment is constructed in this paper. Mathematical analysis about existence of equilibrium points, basic reproduction number, and bifurcation analysis conducted to understand qualitative behaviour of the model. For numerical purposes, we estimated the parameters' values of the model using monthly measles data from Jakarta, Indonesia. Optimal control theory was applied to investigate the optimal strategy in handling measles spread. The results show that all controls succeeded in reducing the number of infected individuals. The cost-effective analysis was conducted to determine the best strategy to reduce number of infected individuals with the lowest cost of intervention. Our result indicates that the use of the first dose measles vaccine with medical treatment is the most optimal strategy to control measles transmission.</p></abstract>

The performance of routine immunization in selected African countries during the first six months of the COVID-19 pandemic.

following the declaration of the COVID-19 pandemic on 11 March 2020, countries started implementing strict control measures, health workers were re-deployed and health facilities re-purposed to assist COVID-19 control efforts. These measures, along with the public concerns of getting COVID-19, led to a decline in the utilization of regular health services including immunization. we reviewed the administrative routine immunization data from 15 African countries for the period from January 2018 to June 2020 to analyze the trends in the monthly number of children vaccinated with specific antigens, and compare the changes in the first three months of the COVID-19 pandemic. thirteen of the 15 countries showed a decline in the monthly average number of vaccine doses provided, with 6 countries having more than 10% decline. Nine countries had a lower monthly mean of recipients of first dose measles vaccination in the second quarter of 2020 as compared to the first quarter. Guinea, Nigeria, Ghana, Angola, Gabon, and South Sudan experienced a drop in the monthly number of children vaccinated for DPT3 and/or MCV1 of greater than 2 standard deviations at some point in the second quarter of 2020 as compared to the mean for the months January-June of 2018 and 2019. countries with lower immunization coverage in the pre-COVID period experienced larger declines in the number of children vaccinated immediately after the COVID-19 pandemic was declared. Prolonged and significant reduction in the number of children vaccinated poses a serious risk for outbreaks such as measles. Countries should monitor coverage trends at national and subnational levels, and undertake catch-up vaccination activities to ensure that children who have missed scheduled vaccines receive them at the earliest possible time.

The performance of routine immunization in selected African countries during the first six months of the COVID-19 pandemic

Introductionfollowing the declaration of the COVID-19 pandemic on 11 March 2020, countries started implementing strict control measures, health workers were re-deployed and health facilities re-purposed to assist COVID-19 control efforts. These measures, along with the public concerns of getting COVID-19, led to a decline in the utilization of regular health services including immunization.Methodswe reviewed the administrative routine immunization data from 15 African countries for the period from January 2018 to June 2020 to analyze the trends in the monthly number of children vaccinated with specific antigens, and compare the changes in the first three months of the COVID-19 pandemic.Results:thirteen of the 15 countries showed a decline in the monthly average number of vaccine doses provided, with 6 countries having more than 10% decline. Nine countries had a lower monthly mean of recipients of first dose measles vaccination in the second quarter of 2020 as compared to the first quarter. Guinea, Nigeria, Ghana, Angola, Gabon, and South Sudan experienced a drop in the monthly number of children vaccinated for DPT3 and/or MCV1 of greater than 2 standard deviations at some point in the second quarter of 2020 as compared to the mean for the months January-June of 2018 and 2019.Conclusioncountries with lower immunization coverage in the pre-COVID period experienced larger declines in the number of children vaccinated immediately after the COVID-19 pandemic was declared. Prolonged and significant reduction in the number of children vaccinated poses a serious risk for outbreaks such as measles. Countries should monitor coverage trends at national and subnational levels, and undertake catch-up vaccination activities to ensure that children who have missed scheduled vaccines receive them at the earliest possible time.

Are community health workers cost-effective for childhood vaccination in India?

IntroductionAccredited Social Health Activists (ASHAs) are female community health workers whose primary role is to promote utilization of primary healthcare services and improve sanitation in rural areas and are financially incentivized for services provided. Prior studies evaluating ASHAs have been largely qualitative, and assess their knowledge, skills, and practice. Globally, there have been very few studies that have quantitatively assessed community health workers. We analyzed the cost effectiveness of ASHAs in facilitating measles vaccination among children under 5 years during 2012–2013. MethodsWe utilized Markov modeling simulating a cohort of children in villages with and without ASHAs. We extrapolated the health states to a lifetime of 68 years to estimate the effects of ASHA intervention. Measles vaccination rates were obtained from 2013 District Level Household and Facilities Survey 4. Other parameter estimates were obtained from a review of relevant literature. ResultsASHA intervention was highly cost effective at $162 per DALY averted compared to no ASHA and remained cost effective with the ASHA incentive increased from $2 to $15, across the range of probabilities and cost parameters. Analyses were sensitive to probability of death due to childhood pneumonia, susceptibility to measles after one dose measles vaccine, and probability of pneumonia after measles infection. ConclusionASHAs were cost-effective under a wide range of scenarios even when a single health outcome such as measles vaccination was considered. The Government of India and individual state governments of India should consider increasing the incentives provided to ASHAs.

Status of Measles Elimination in Eleven Countries with High Routine Immunisation Coverage in The WHO African Region

Measles elimination is defined as the absence of endemic measles virus transmission in a defined geographic area for at least 12 months in the presence of a well-performing surveillance system. The WHO framework for verification of measles elimination indicates that the achievement of measles and/or rubella elimination should be verified for individual countries. We identified 11 high performing countries based on their first dose measles vaccination coverage, and looked at their performance across the various programmatic parameters, to see if they are ready to undertake the verification of measles elimination. We identified 11 countries with >90% measles first dose coverage for the most recent 5 years according to the WHO UNICEF estimates of national immunisation coverage. We analysed vaccination coverage and surveillance performance in these countries. Algeria, Botswana, Gambia, Mauritius, Rwanda, Seychelles have maintained measles first dose (MCV1) coverage of 95% or more since 2011. In 2015, only Algeria, Cape Verde and Seychelles had coverage of 95% or more for the second dose of measles vaccine (MCV2). Of the 22 supplemental immunisation activities (SIAs) among the 11 countries, only 6 had administrative coverage of less than 95%. Only Rwanda and Lesotho attained the case-based surveillance performance targets in all the five years. Despite their high routine first dose measles immunisation coverage, all of the 11 countries have some program gaps indicating that they do not meet all the criteria to undergo verification of elimination at this point. It is recommended for these countries to set up national verification committees as per the WHO framework for verification of measles elimination, in order to initiate the documentation and monitoring of progress, and to address programmatic gaps in the coming years.

Progress Towards Measles Elimination in Nigeria: 2012 - 2016

Nigeria has adopted the African Regional measles elimination targets and is implementing the recommended strategies. Nigeria provides routine measles vaccination for children aged 9 months. In addition, since 2006, Nigeria has been conducting nationwide measles supplemental Immunisation activities (SIAs) or mass vaccination campaigns every 2 years, and has established measles case-based surveillance. We reviewed routine and supplemental measles immunization coverage data, as well as measles case-based surveillance data from Nigeria for the years 2012 - 2016, in an attempt to determine the country's progress towards these elimination targets. The first dose measles vaccination coverage in Nigeria ranged from 42% and 54% between 2012 and 2015, according to the WHO UNICEF national coverage estimates. Nigeria achieved 84.5% coverage by survey following the 2015 nationwide measles supplemental immunisation activities (SIAs). During this period, the incidence of confirmed measles ranged from 25 - 300 confirmed cases per million population per year, with the Northern States having significantly higher incidence as compared to the Southern States. At the same time, the pattern of confirmed cases indicated a consistent shift in epidemiological susceptibility including older age children. In order to accelerate its progress towards the measles elimination targets, Nigeria should build population immunity on a sustainable basis by addressing systemic issues in order to scale up routine immunisation coverage, especially in the Northern half of the country; tailoring the target age for measles SIAs so as to sharply reduce measles incidence in age groups heavily affected by the disease; effectively mobilising resources and improving the quality of planning and coverage outcome of SIAs.

Maternal measles antibodies and infant susceptibility in Chandigarh, India

Background: Measles continues to be endemically transmitted in many parts of the world including India. The single dose measles vaccine was first introduced in India in 1985 with recommendation for a second dose added in 2010. Consequently, most mothers and women of reproductive age in India have not received the two recommended doses of vaccine. This study seeks to understand the impact of the changing dynamic of natural measles infection versus vaccination on maternal and infant measles antibody levels. We compare antibodies in infants and their mothers at the time of the birth of their child and through the infant's first year of life. Methods & Materials: Pregnant mothers were systematically selected into this population-based cohort study in Chandigarh, India. Serum samples were tested for anti-measles IgG antibodies from mothers at the time of their infant's birth, and from infants at birth, 3, 6, 9, and 12 months. A positive measles reading (indicating immunity and protection from subsequent infection) was defined as > 12 U/ml. The study is ongoing. Results: Of the 306 mother-infant dyads enrolled in the study, the mean maternal IgG titer of infants who were IgG positive was 97.0 U/ml (SD ± 65.0) and the mean maternal IgG titer of infants who were IgG negative was 18.7 U/ml (SD ± 29.5). Mean antibody tiers in mothers were also higher for mothers whose infants tested IgG positive at three months, 142.8 U/ml (SD ± 60.1), compared to those testing IgG negative 65.7 U/ml (SD ± 56.6). Infant antibody titers at birth were significantly greater among infants whose mothers had reported measles infection 145.6 U/ml (SD ± 72.4) than among mothers who were vaccinated 102.1 U/ml (SD ± 63.2) (P = 0.01). Conclusion: Greater measles antibody titers in mothers resulted in infants retaining immunity at birth and at 3 months. Moreover, mothers who previously had disease gave birth to infants with higher titers than infants born to vaccinated mothers. Programs targeting vaccination of young adult women of reproductive age could bolster population level immunity and also enable mothers to pass on higher levels of protective antibodies to their infants.

Dynamic maternal measles antibody level in infants: a longitudinal study

To understand the dynamic maternal measles antibody level in infants in Guangzhou. Women who delivered babies in a maternal and child health care hospital in Guangzhou and their infants who were never affected by measles were included in our study. All the serum samples collected from mothers and infants were tested by using enzyme linked immunosorbent assay(ELISA)for the quantitative measurement of measles IgG antibodies. A longitudinal sero-epidemiological study was conducted to investigate the duration of the presence of measles maternal antibodies in infants based on the measurement at different time points(0, 3, 5, 7 month). A total of 689 mothers and their 691 infants(two pairs of twins)were included in the study. The concentration and the sero-positivity rate of measles antibody in mothers was 513.8 mIU/ml and 81.6% respectively. The concentration and the sero-positivity rate of measles antibody in infants was 732.8 mIU/ml and 87.3%, respectively. The measles antibody levels of newborns were positively associated with those of mothers(r=0.917 5, P<0.001), which declined rapidly at 3 months after birth and mostly turned to be negative at 7 months after birth. Measles antibody turned be negative at 3 months after birth in low, middle level groups, but remained to be positive in high level group at 5 months after birth. The maternal measles antibody could rarely protect infants at age of 8 months even though mother had been vaccinated or acquired natural immunity. It is suggested to adjust the time of the first dose measles vaccination in infants and increase the measles antibody level of child bearing aged women to reduce the incidence of measles in infants.

Comparison of Impact of Single Dose and Multiple Dose Measles Vaccination Strategies on Measles Transmission Patterns

Background: Multiple dose measles vaccination intervention was applied in Gweru City, Zimbabwe, in 1990-96, following a single dose applied at 9 months of age during 1983-89. In the same periods in Bulawayo, only a single dose of measles vaccine was applied to children at 9 months of age. This study investigated the impact on measles transmission patterns of multiple dose measles vaccination strategy. Study design: Quasi-experimental community intervention applied in Gweru city with Bulawayo city as a control. The intervention included a single mass vaccination campaign carried out in1990 targeted at children aged 12-119 months irrespective of their vaccination status or disease history. Children born after 1990 were vaccinated at 9 months of age plus another single dose applied at any point between ages of 12 and 23 months (revaccination). Subjects: Measles cases were identified in both cities through surveillance. Results: Mean coverage rates for measles vaccine applied at 9 months of age were in 1983-89 85.7% and 84.6% in Bulawayo and Gweru respectively, while in 1990-96 they were 89.0% and 89.7%, respectively. In both periods the vaccine coverage rates were not significantly different in the two cities (p=0.464). In the 12-23 months age group, Gweru measles vaccination coverage rate in 1990 was 83% for single dose and 82.4% for second dose in 1990-96. Measles incidence rates in 1983-89 in both cities significantly declined and were not significantly different (p=0.898). Median incidence rates of measles in1990-96 were 131.0 and 19.0/100 000 population in Bulawayo and Gweru respectively and these were significantly different (p= 0.021). Bulawayo had measles epidemics in 1992, 1993, 1994 and 1996. In Bulawayo in 1993-96 vaccinated measles cases accounted for a median of 58% of all reported cases aged 10-119 months. Median incidence rates of measles among vaccine failures aged 10-119 months in 1993-96 in Bulawayo and Gweru were 419.1 and 13.1/100 000 population respectively and these incidence rates were significantly different (p= 0.021). In Bulawayo in 1993-96 cases aged 60-119 months accounted for a median of 56.5 % of all reported cases. Median incidence rates of measles among cases aged 60-119 months in 1993-96 in Bulawayo and Gweru were 869.9 and 26.9/100 000 population respectively and these rates were significantly different (p=0.021). Conclusion: Multiple dose vaccination strategies led to significantly reduced measles transmission in Gweru (compared to Bulawayo) in 1990-1996 by minimizing occurrence of vaccine failures and occurrence of cases in older children aged 60-119 months.

Measles: The past, the present and the future

Measles is one of the most infectious diseases known to affect man. It spreads rapidly from an index case to many susceptible individuals resulting in cycles of epidemics in different parts of the world especially in the African continent. The contribution of measles to childhood mortality and morbidity remains high because it gives rise to complications such as pneumonia, malnutrition and blindness. Measles vaccine is known to be efficacious and effective; however appearance of epidemics in parts of Europe and the USA in recent times underscores the fact that low vaccine uptake will always leave a large number of susceptible individuals with a potential for epidemics. The history, aetiopathogenesis, clinical features (including complications), diagnostic tools, treatment and prevention are discussed in this article. The most important steps to prevent measles cases and deaths would be to institutionalize the two dose measles vaccine regime; give supplemental Vitamin A; strengthen health systems to be able to adequately deliver the vaccine and supplement, carry out surveillance and offer treatment for cases. There is no doubt that global partnerships remain relevant in order to consolidate and accelerate prevention of measles, thus, they must continue to be supported.

WHO's Initiatives to Control Vaccine Preventable Diseases (VPD) and Labnet for Targeted VPDs in the Western Pacific Region

WHO's Initiatives to Control Vaccine Preventable Diseases (VPD) and Labnet for Targeted VPDs in the Western Pacific Region

Measles susceptibility in children in Karachi, Pakistan

Measles, despite being vaccine preventable is still a major public health problem in many developing countries. We estimated the proportion of measles susceptible children in Karachi, the largest metropolitan city of Pakistan, one year after the nationwide measles supplementary immunization activity (SIA) of 2007–2008. Oral fluid specimens of 504 randomly selected children from Karachi, aged 12–59 months were collected to detect measles IgG antibodies. Measles antibodies were detected in only 55% children. The proportion of children whose families reported receiving a single or two doses of measles vaccine were 78% and 12% respectively. Only 3% of parents reported that their child received measles vaccine through the SIA. Among the reported single dose measles vaccine recipients, 58% had serologic immunity against measles while among the reported two dose measles vaccine recipients, 64% had evidence of measles immunity. Urgent strengthening of routine immunization services and high quality mass vaccination campaigns against measles are recommended to achieve measles elimination in Pakistan.

A review of measles vaccine failure in developing countries

Summary Measles is one of the major preventable childhood killer diseases in developing countries. Annually about 70 million cases occur worldwide. Measles vaccine has been developed over decades to prevent and control measles. Although national immunization programsprevent over 80 million cases of measles and 4.5 million deaths annu- ally, it is estimated that over 30 million cases and 875,000 d~ths still occur every yeat. High transmksion of measles despite high coverage with I-dose measles vaccine has been reported in some developing countries. Some of the reasons for vaccine failure in developing countries include; poor seroconversion, questionable potency of vaccines due to problem with cold chain that ultimately affect the quality of vaccine and waning immunity. To prevent outbreaks of measles in developing countries, there is needfor second dose of measles vaccine to take care of vaccine failures. This measure is necessary even in countries where there is high coverage with one dose of measles vaccine. The relevant International Agencies need to develop second dose measles vaccination policiesfor developing countries as obtains in some developed countries. Key words: Measles vaccine, failure, developing countries