Search

Background: In November 2009, Sierra Leone conducted a preventive yellow fever (YF) vaccination campaign targeting individuals aged nine months and older in six health districts. The campaign was integrated with a measles follow-up campaign throughout the country targeting children aged 9-59 months. For both campaigns, the operational objective was to reach 95% of the target population. During the campaign, we used clustered lot quality assurance sampling (C-LQAS) to identify areas of low coverage to recommend timely mop-up actions. Methods: We divided the country in 20 non-overlapping lots. Twelve lots were targeted by both vaccinations, while eight only by measles. In each lot, five clusters of ten eligible individuals were selected for each vaccine. The upper threshold (UT) was set at 90% and the lower threshold (LT) at 75%. A lot was rejected for low vaccination coverage if more than 7 unvaccinated individuals (not presenting vaccination card) were found. After the campaign, we plotted the C-LQAS results against the post-campaign coverage estimations to assess if early interventions were successful enough to increase coverage in the lots that were at the level of rejection before the end of the campaign. Results: During the last two days of campaign, based on card-confirmed vaccination status, five lots out of 20 (25.0%) failed for having low measles vaccination coverage and three lots out of 12 (25.0%) for low YF coverage. In one district, estimated post-campaign vaccination coverage for both vaccines was still not significantly above the minimum acceptable level (LT = 75%) even after vaccination mop-up activities. Conclusion: C-LQAS during the vaccination campaign was informative to identify areas requiring mop-up activities to reach the coverage target prior to leaving the region. The only district where mop-up activities seemed to be unsuccessful might have had logistical difficulties that should be further investigated and resolved. [ABSTRACT FROM AUTHOR]

Vaccines have made a major contribution to public health, including the eradication of one deadly disease, small pox, and the near eradication of another, poliomyelitis. Through the introduction of new vaccines, such as those against rotavirus and pneumococcal diseases, and with further improvements in coverage, vaccination can significantly contribute to the achievement of the health-related United Nations Millennium Development Goals. The Global Immunization Vision and Strategy (GIVS) was developed by WHO and UNICEF as a framework for strengthening national immunization programmes and protect as many people as possible against more diseases by expanding the reach of immunization, including new vaccines, to every eligible person. This paper briefly reviews global progress and challenges with respect to public vaccination programmes. The most striking recent achievement has been that of reduction of global measles mortality from an estimated 750,000 deaths in 2000 down to 197,000 in 2007. Global vaccination coverage trends continued to be positive. In 2007 most regions reached more than 80% of their target populations with three doses of DPT containing vaccines. However, the coverage remains well short of the 2010 goal on 90% coverage, particularly in the WHO region of Africa (estimated coverage 74%), and South-East Asia, (estimated coverage 69%). Elements that have contributed to the gain in immunization coverage include national multi-year planning, district-level planning and monitoring, re-establishment of outreach services and the establishment of national budget lines for immunization services strengthening. Remaining challenges include the need to: develop and implement strategies for reaching the difficult to reach; support evidence-based decisions to prioritize new vaccines for introduction; strengthening immunization systems to deliver new vaccines; expand vaccination to include older age groups; scale up vaccine preventable disease surveillance; improve quality of immunization coverage monitoring and use the data to improve programme performance; and explore financing options for reaching the GIVS goals, particularly in lower-middle income countries. Although introduction of new vaccines is important, this should not be at the expense of sustaining existing immunization activities. Instead the introduction of new vaccine introduction should be viewed as an opportunity to strengthen immunization systems, increase vaccine coverage and reduce inequities of access to immunization services. [ABSTRACT FROM AUTHOR]

Background: The Global Immunization Vision and Strategy (GIVS) (2006-2015) aims to reach and sustain high levels of vaccine coverage, provide immunization services to age groups beyond infancy and to those currently not reached, and to ensure that immunization activities are linked with other health interventions and contribute to the overall development of the health sector.Objective: To examine mid-term progress (through 2010) of the immunization coverage goal of the GIVS for 194 countries or territories with special attention to data from 68 countries which account for more than 95% of all maternal and child deaths.Methods: We present national immunization coverage estimates for the third dose of diphtheria and tetanus toxoid with pertussis (DTP3) vaccine and the first dose of measles containing vaccine (MCV) during 2000, 2005 and 2010 and report the average annual relative percent change during 2000-2005 and 2005-2010. Data are taken from the WHO and UNICEF estimates of national immunization coverage, which refer to immunizations given during routine immunization services to children less than 12 months of age where immunization services are recorded.Results: Globally DTP3 coverage increased from 74% during 2000 to 85% during 2010, and MCV coverage increased from 72% during 2000 to 85% during 2010. A total of 149 countries attained or were on track to achieve the 90% coverage goal for DTP3 (147 countries for MCV coverage). DTP3 coverage ≥ 90% was sustained between 2005 and 2010 by 99 countries (98 countries for MCV). Among 68 priority countries, 28 countries were identified as having made either insufficient or no progress towards reaching the GIVS goal of 90% coverage by 2015 for DTP3 or MCV. DTP3 and MCV coverage remained < 70% during 2010 for 16 and 21 priority countries, respectively.Conclusion: Progress towards GIVS goals highlights improvements in routine immunization coverage, yet it is troubling to observe priority countries with little or no progress during the past five years. These results highlight that further efforts are needed to achieve and maintain the global immunization coverage goals. [ABSTRACT FROM AUTHOR]