PROGRESS IN GLOBALMEASLES CONTROL, 2000-2010

Saturday, 5th of May 2012

• PROGRESS IN GLOBAL MEASLES CONTROL, 2000–2010

Conclusions below; full text, in French and English, is at http://www.who.int/wer/2012/wer8705.pdf

After 8 years of decreases, the number of reported measles cases remained stable in 2009 and increased in 2010. Continued decreases during 2009–2010 in WPR and SEAR contrasted with large outbreaks in EMR during 2009, in EUR during 2010 and in AFR during 2009 and 2010. In 2010, approximately 90% of cases were reported from AFR, EUR, and SEAR and 40% of member states globally did not meet the reported incidence target of <5 cases per million population.

The rise in cases occurred despite a steady rise in regional and global MCV1 coverage and high reported coverage through SIAs. Measles surveillance data and outbreak investigations provided critical information to identify gaps in population immunity, underserved populations, and programme weaknesses, which led to corrective actions and refinements of vaccination strategies.

In Iraq, Lesotho, Malawi, the Philippines, South Africa and Zimbabwe the target age group for planned SIAs was widened beyond 9–59 months of age to include older age groups affected by the outbreaks.

In Zimbabwe, to build confidence in both routine and SIA vaccination among religious groups, specialized communication strategies were developed, the opening hours of vaccination services were customized to meet the community’s needs, and government authorities advocated for vaccination with religious leaders. In Ethiopia, a comprehensive review of previous SIA implementation and surveillance data led to a shift from using multi-year subnational SIAs to implementation of a national SIA conducted in 2 phases over 6 months and to the development of best practices used in the 2010 SIA. Surveillance data analysis and outbreak investigations should be used to complement monitoring of vaccination coverage in order to identify gaps in vaccination programmes.

Interpretation of coverage and surveillance is complicated by some limitations. Vaccination coverage is often biased by inaccurate estimates of the target population and inaccurate reporting of doses delivered. Surveillance does not capture all measles cases due to incomplete reporting from the community and from one level of the health system to the next. Comparison of annual measles case totals and incidence may be difficult if completeness of reporting changes from year to year.

Measles elimination goals have been set by all WHO Regions, except SEAR, and in the Region of the Americas elimination has been achieved and maintained since 2002. In July 2010, a Global Technical Consultation commissioned by WHO to evaluate the feasibility of measles eradication concluded that measles can and should be eradicated.10 The WHO Strategic Advisory Group of Experts on Immunization endorsed this conclusion in November 2010, adding that a target date should be based on measurable progress made towards existing goals and targets.11 In 2010, the world’s 2 most populous countries made promising advances in measles control: China held the largest-ever SIA, vaccinating >103 million children, and India started implementation of a 2-dose vaccination strategy.

 

Building on the previous WHO and UNICEF strategy, and recognizing the burden of congenital rubella syndrome and availability of combination vaccines, the Measles Initiative12 has developed a 2012–2020 Global Measles and Rubella Strategic Plan. This plan aims to

(i) achieve and maintain high levels of population immunity through high coverage with 2 doses of measles- and rubella-containing vaccines, (ii) establish effective surveillance to monitor disease and evaluate progress, (iii) develop and maintain outbreak preparedness for rapid response and appropriate case management, (iv) communicate and engage to build public

confidence in and demand for vaccination, and (v) conduct research and development to support operations and improve vaccination and diagnostic tools.

Reversing the recent increases in reported cases and achieving further progress towards 2015 targets will require meeting the following key challenges: (i) declining political and financial commitments to measles control; (ii) failure to reach uniform high coverage with 2 doses

of MCV through routine services or SIAs; and (iii) inadequate monitoring subnationally of MCV1 and MCV2 coverage to guide interventions to increase coverage.

 

Reductions in measles mortality accounted for 23% of the estimated decline in all-cause child mortality from 1990 to 2008.13 This contribution to reaching Millennium Development Goal 4 is at risk unless these challenges can be overcome.