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Background. Information on measles vaccine effectiveness (VE) is critical to help inform policies for future global measles control goals. Methods. We reviewed results of VE studies published during 1960-2010. Results. Seventy papers with 135 VE point estimates were identified. For a single dose of vaccine administered at 9-11 months of age and ≥12 months, the median VE was 77.0% (interquartile range [IQR], 62%-91%) and 92.0% (IQR, 86%-96%), respectively. When analysis was restricted to include only point estimates for which vaccination history was verified and cases were laboratory confirmed, the median VE was 84.0% (IQR, 72.0%- 95.0%) and 92.5% (IQR, 84.8%-97.0%) when vaccine was received at 9-11 and ≥12 months, respectively. Published VE vary by World Health Organization region, with generally lower estimates in countries belonging to the African and SouthEast Asian Regions. For 2 doses of measles-containing vaccine, compared with no vaccination, the median VE was 94.1% (IQR, 88.3%-98.3%). Conclusions. The VE of the first dose of measles-containing vaccine administered at 9-11 months was lower than what would be expected from serologic evaluations but was higher than expected when administered at ≥12 months. The median VE increased in a subset of articles in which classification bias was reduced through verified vaccination history and laboratory confirmation. In general, 2 doses of measles-containing vaccine provided excellent protection against measles. [ABSTRACT FROM AUTHOR]

Abstract: Objective: We investigated a large measles outbreak that occurred in 2009 in Burkina Faso in order to describe the epidemic, assess risk factors associated with measles, and estimate measles vaccine effectiveness. Methods: We reviewed national surveillance and measles vaccine coverage data, and conducted a case–control study in three geographic areas. Case-patients were randomly selected from the national case-based measles surveillance database or, when a case-patient could not be traced, were persons in the same community who experienced an illness meeting the WHO measles clinical case definition. Controls were matched to the same age stratum (age 1–14 years or age 15–30 years) and community as case-patients. Risk factors were assessed using conditional logistic regression. Results: Lack of measles vaccination was the main risk factor for measles in all three geographic areas for children aged 1–14 years (adjusted matched odds ratio [aMOR] [95% confidence interval (CI)], 19.4 [2.4–155.9], 5.9 [1.6–21.5], and 6.4 [1.8–23.0] in Bogodogo, Zorgho, and Sahel, respectively) and persons aged 15–30 years (aMOR [95% CI], 3.2 [1.1–9.7], 19.7 [3.3–infinity], 8.0 [1.8–34.8] in Bogodogo, Zorgho, and Sahel, respectively). Among children aged 1–14 years, VE of any measles vaccination prior to 2009 was 94% (95% CI, 45–99%) in Bogodogo, 87% (95% CI, 37–97%) in Zorgho, and 84% (95% CI, 41–96%) in Sahel. Main reasons for not receiving measles vaccination were lack of knowledge about vaccination campaigns or need for measles vaccination and absence during vaccination outreach or campaign activities. Conclusion: These results emphasize the need for improved strategies to reduce missed opportunities for vaccination and achieve high vaccination coverage nationwide in order to prevent large measles outbreaks and to continue progress toward measles mortality reduction. [Copyright &y& Elsevier]

Background. The Region of the Americas eliminated measles in 2002 through high first-dose routine measles vaccine coverage and vaccination campaigns every 4-6 years; a second routine dose at school entry was added in some countries. The impact of this second routine dose on measles elimination was evaluated. Methods. Data on socioeconomic factors, demographic characteristics, vaccination coverage, and the estimated proportion of children (<15 years of age) susceptible to measles were compiled. Countries were grouped using propensity score methods, and Kaplan-Meier curves were used to compare time to measles elimination between countries with a 1-dose schedule and those with a 2-dose schedule. Results. One-dose (n =14) and 2-dose (n = 7) countries did not differ with respect to median routine firstdose measles vaccine coverage, median coverage for 3 measles campaigns, or estimated percentage of susceptible children after routine first vaccination dose and campaigns. Compared with 1-dose countries, 2-dose countries had higher median gross national income per capita (P =.002), percentage of population living in urban areas (P =.04), and female literacy (P =.01), as well as lower infant mortality (P = .007); however, no differences in time to elimination were found. Conclusions. One-dose and 2-dose countries had similar times to measles elimination despite socioeconomic differences between their populations. A second routine dose might not have hastened measles elimination, because threshold immunity needed to eliminate measles was achieved with high first routine dose coverage and vaccination campaigns. Further research will be needed to determine the applicability of these findings to other regions. [ABSTRACT FROM AUTHOR]

Background. The Member States of the European Region (EUR) of the World Health Organization (WHO) have made great progress towards achieving the goal of measles elimination by 2010. Methods. Measles surveillance and vaccine coverage data from 2003-2009 reported to WHO were analyzed. A review of feasibility of reaching the elimination goal by the 2010 target date was conducted in 2009. Results. From 2003-2009, the measles incidence decreased dramatically and coverage with 2 doses of measles vaccine increased among wide age groups of susceptible persons. With the decrease of disease incidence and the reduction of outbreaks in the eastern part of EUR, the proportion of reported cases in the western part increased. In 2009, outbreaks in 5 countries accounted for 89.6% of reported cases. Challenges to reach the 2010 goal include ongoing outbreaks with reestablished endemicity in some countries, decreased demand for vaccines with an increased focus on the measles vaccine safety, and population groups with limited access to immunization services. Conclusions. Measles elimination in EUR is attainable, albeit not by 2010. EUR countries should ensure political commitment and resources to protect the gains made to date and address these challenges to sustain the progress and achieve the elimination goal. [ABSTRACT FROM AUTHOR]

Background. In Africa before the introduction of measles vaccination, measles primarily affected young children. To describe measles epidemiology in Africa since the start of accelerated measles control activities in 2001, we analyzed regional measles case-based surveillance data for 2002-2009. Methods. Country-years were grouped by 10-year moving average of routine measles vaccination coverage (aMCV1). Age was log transformed, and pair-wise comparisons of means were made. A x2 test was used to assess association between coverage and age groups. Cumulative percent curves and percentiles of age, dot plots with Loess curve, and Spearman rank correlation coefficient were calculated. Results. Of 180,284 suspected cases, 73,009 (41%) were confirmed as measles. Of these, the mean age was 79 months (median, 36 months; interquartile range, 16-96 months) and significantly younger in country-years with <50% aMCV1 than those with 50%-74% aMCV1 (P = .03) and ≥75% (P = .02). With increasing coverage, there was a slight decrease in age in the 10th and 25th and moderate increase in age in the 50th, 75th, and 90th percentiles. Conclusions. During 2002-2009, the median age of confirmed measles was 36 months. In countries with ≥50% aMCV1 coverage compared with low-coverage countries, age shifted to older children and young adults; for infants, age decreased slightly with higher coverage. [ABSTRACT FROM AUTHOR]

Highlights a measles-rubella mass immunization campaign launched in Albania in November 2000. Catch-up vaccination campaign for all children aged 1-14 years; Achievement of high coverage among children aged 1 year with the first dose of a measles-containing vaccine; Routine second dose of measles-containing vaccine for children at age 5 years; Improvement of measles surveillance.