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Lessons from Measles outbreaks in the African Region. Annual Measles Partnership meeting Feb 2007 Washington DC. Outline. Quality of surveillance Measles outbreaks in 2006 Lessons learnt. Quality of surveillance Measles outbreaks in 2006 Lessons learnt.
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Lessons from Measles outbreaks in the African Region Annual Measles Partnership meeting Feb 2007 Washington DC
Outline • Quality of surveillance • Measles outbreaks in 2006 • Lessons learnt
Quality of surveillance • Measles outbreaks in 2006 • Lessons learnt
The AFR measles surveillance and lab network (Feb 2007) • A total population of 668.5 million • under case based surveillance for measles
Measles surveillance performance indicators in AFR. 2002 - 2006
Measles surveillance performance & results. AFR. 2006 (2) • 22 countries > 2 suspected cases investigated per 100,000 population • 15 countries >80% districts reporting • 24 countries > 60% districts reporting • 25 countries < 1: 100,000 incidence of confirmed measles
Incidence of confirmed measles per 100,000 population by country. 2006
Quality of surveillance • Measles outbreaks in 2006 • Lessons learnt
Measles outbreaks in the African Region (2004 - 2006) • In 2004, 80 (5%) of a total of 1590 districts covered by the case based surveillance system reported outbreaks • In 2005, outbreaks in 47 (3%) districts out of 1850 • In 2006, 178 (6%) of 2923 districts in 12 countries have experienced outbreaks. NB: Tanzania database incomplete
Probable causes of measles outbreaks in the African Region in 2006 • Accumulation of unvaccinated cohorts (~ over 3 -4 years) due to a combination of factors • sub-national gaps in routine EPI coverage: • Angola, Benin, DR Congo, Ethiopia, Mali, Tanzania, Uganda • delays in conducting follow up SIAs: • Kenya, Zambia, Ghana • cross border spread of outbreaks: • DR Congo, Rwanda
Trends of confirmed measles cases. Kenya. 2003 –2006. F-up SIAs done July ‘06 F-up SIAs postponed Catch-up SIAs: June ‘02
Confirmed measles cases by age and vaccination status. Kenya. 2006
Trends of confirmed measles cases. Uganda. 2002 – 2006. F-up SIAs: Nov 2006 Catch-up SIAs: Oct 2003
Confirmed measles cases by age and vaccination status. Uganda. 2006
Probable causes of measles outbreaks in the African Region in 2006 (2) • Program gaps leading to a cohort of older children (ages 6 – 7.5 years) unprotected in some districts • Tanzania (124 districts) • 1999 / 2000 SIAs: all 9 – 59 months (in 91 districts) • 2001 SIAs: 9 months – 14 years (in 31 districts) • 2002 SIAs: 7 – 14 years (in 89 districts) • 2005 SIAs: 9 - 59 months (nation-wide follow up)
Age distribution of measles cases. Dar es Salaam, Tanzania July – mid Oct. 2006
Quality of surveillance • Measles outbreaks in 2006 • Lessons learnt
Lessons learnt • Postponing measles follow-up SIAs beyond 36 months is risky even in “high” coverage countries • Other platforms available for integration • Disparities in the district level coverage • Surveillance and outbreak investigation should provide better quality epidemiological information • Training and technical support for outbreak investigation
Lessons learnt (2) • Political visibility of outbreaks; • an opportunity to advocate for routine EPI and good quality follow up SIAs • Identify districts at high risk for outbreaks for extra support to intensify immunization activities