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BACKGROUND: Delivering vaccination services during the second year of life (2YL)1 provides countries with an opportunity to achieve greater coverage, to provide booster doses and vaccines missed during the first year of life, as well as contribute towards disease control and elimination goals. METHODS: Using data from demographic health surveys (DHSs) conducted during 2010 to 2016, this paper explores the proportion of missed opportunities for vaccinations generally provided during routine immunization among children in their 2YL. RESULTS: DHS data in 46 countries surveyed 478,737 children, from which 169,259 children were 12-23 months old and had vaccination/health cards viewed by surveyors. From this group, 69,489 children aged 12-23 months had contact with health services in their 2YL. Three scenarios for a missed opportunity for vaccinations were analysed: (1) a child received one vaccine in the immunization schedule and was eligible for another vaccine, but did not receive any further vaccination, (2) a child received a vitamin A supplementation (VAS) and was due for a vaccine, but did not receive vaccines that were due, and (3) a child was taken to a health facility for a sick visit and was due (and eligible) for a vaccine, but did not receive the vaccine. A total of 16,409 (24%) children had one or more missed opportunities for vaccinations. CONCLUSION: This analysis highlights the magnitude of the problem of missed opportunities in the 2YL. The global community needs to provide better streamlined guidance, policies and strategies to promote vaccination screenings at well-child and sick child visits in the 2YL. Where they do not exist, well-child visits in the 2YL should be established and strengthened.

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The Global Polio Eradication Initiative has built an extensive infrastructure with capabilities and resources that should be transitioned to measles and rubella elimination efforts. Measles continues to be a major cause of child mortality globally, and rubella continues to be the leading infectious cause of birth defects. Measles and rubella eradication is feasible and cost saving. The obvious similarities in strategies between polio elimination and measles and rubella elimination include the use of an extensive surveillance and laboratory network, outbreak preparedness and response, extensive communications and social mobilization networks, and the need for periodic supplementary immunization activities. Polio staff and resources are already connected with those of measles and rubella, and transitioning existing capabilities to measles and rubella elimination efforts allows for optimized use of resources and the best opportunity to incorporate important lessons learned from polio eradication, and polio resources are concentrated in the countries with the highest burden of measles and rubella. Measles and rubella elimination strategies rely heavily on achieving and maintaining high vaccination coverage through the routine immunization activity infrastructure, thus creating synergies with immunization systems approaches, in what is termed a "diagonal approach."

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OBJECTIVES: Measles was virtually eliminated in South Africa following control activities in 1996/7. However, from July 2003 to November 2005, 1676 laboratory-confirmed measles cases were reported in South Africa. We investigated the outbreak's cause and the role of HIV. DESIGN: We traced laboratory-confirmed case-patients residing in the Johannesburg metropolitan (JBM) and O. R. Tambo districts. We interviewed laboratory--or epidemiologically confirmed case-patients or their caregivers to determine vaccination status and, in JBM, HIV status. We calculated vaccine effectiveness using the screening method. SETTING: Household survey in JBM and O. R. Tambo districts. Outcome measures. Vaccine effectiveness, case-fatality rate, and hospitalisations. RESULTS: In JBM, 109 case-patients were investigated. Of the 57 case-patients eligible for immunisation, 27 (47.4%) were vaccinated. Fourteen (12.8%) case-patients were HIV infected, 46 (42.2%) were HIV uninfected, and 49 (45.0%) had unknown HIV status. Among children aged 12-59 months, vaccine effectiveness was 85% (95% confidence interval (CI): 63, 94) for all children, 63% for HIV infected, 75% for HIV uninfected, and 96% for children with unknown HIV status. (Confidence intervals were not calculated for sub-groups owing to small sample size.) In O. R. Tambo district, 157 case-patients were investigated. Among the 138 case-patients eligible for immunisation, 41 (29.7%) were vaccinated. Vaccine effectiveness was 89% (95% CI 77, 95). CONCLUSIONS: The outbreak's primary cause was failure to vaccinate enough of the population to prevent endemic measles transmission. Although vaccine effectiveness might have been lower in HIV-infected than in uninfected children, population vaccine effectiveness remained high.

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BACKGROUND: Shortly after a measles supplementary immunization activity (SIA) targeting children from 9 months to 14 years of age that achieved high coverage, Burkina Faso had a large, serologically confirmed measles outbreak. To investigate the causes of this first reported failure of a widely successful measles control strategy we conducted a case-control study. METHODS: Serologically confirmed measles cases aged > or =9 months at the time of the SIA in 6 heavily affected districts were frequency matched on age to 3 controls recruited from people frequenting health centres in the same districts. RESULTS: Between January and July 2002, 1287 measles cases were reported throughout Burkina Faso. Of the 707 cases that were serologically confirmed, 358 (51%) were from 9 months to 14 years of age and 265 (37%) were > or =15 years of age. Among cases and controls from 9 months to 14 years of age significant risk factors for measles were lack of measles vaccination and, in the unvaccinated, recent travel to Cote d'Ivoire. Of the recent measles cases in Cote d'Ivoire 54% were there when exposed to measles. Among adults, risk factors included non-vaccination and the lack of school attendance during childhood. Vaccine effectiveness was estimated to be 98%. CONCLUSIONS: Migration of children between Cote d'Ivoire and Burkina Faso played a major role in the failure of the SIA to interrupt measles transmission. Synchronization of measles control activities should be a high priority in countries with regions where much migration occurs.

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From 1996 to 2000, several African countries accelerated measles control by providing a second opportunity for measles vaccine through supplemental campaigns. Fifteen countries completed campaigns in children aged 9 months to 14 years. Seven countries completed campaigns in children aged 9-59 months. In almost all countries that conducted campaigns in children aged 9 months to 14 years, measles deaths were reduced to near zero. In six countries, near-zero measles mortality has been maintained for 4-6 years. Supplemental immunization in children <5 years old was only partially effective (range, 0-67%) in reducing mortality. Measles cases decreased by 50% when routine vaccination coverage increased from 50% to 80%. Initial measles campaigns in children aged 9 months to 14 years, follow-up campaigns in those aged 9-59 months every 3-5 years, and increased routine coverage to 80% will be needed to reduce and maintain measles deaths in African countries at near zero.

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