Lessons from Measles outbreaks in the African Region

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Lessons from Measles outbreaks in the African
Region
Annual Measles Partnership meeting Feb
2007 Washington DC
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(No Transcript)
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Outline

• Quality of surveillance
• Measles outbreaks in 2006
• Lessons learnt

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• Quality of surveillance
• Measles outbreaks in 2006
• Lessons learnt

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The AFR measles surveillance and lab network (Feb
2007)

• A total population of 668.5 million
• under case based surveillance for measles

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Measles surveillance performance indicators in
AFR. 2002 - 2006
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Measles surveillance performance results. AFR.
2006
Indicator/ parameter Result
suspected cases reported 21580
investigated with blood specimens 93
districts reporting at least 1 suspected case 54
lab confirmed cases 30
total confirmed measles cases 7707
Incidence rate of confirmed measles 1.2 per 100,000 population
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Measles surveillance performance results. AFR.
2006 (2)

• 22 countries gt 2 suspected cases investigated per
  100,000 population
• 15 countries gt80 districts reporting
• 24 countries gt 60 districts reporting
• 25 countries lt 1 100,000 incidence of confirmed
  measles

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Incidence of confirmed measles per 100,000
population by country. 2006
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• Quality of surveillance
• Measles outbreaks in 2006
• Lessons learnt

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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

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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

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Outbreak countries. AFR. 2006
Country Average MCV coverage (03 05) Interval b/n last SIAs and onset of outbreak (months) () districts involved Size of largest cluster (cases/ district) Confirmed measles Incidence rate
Angola 57 32 13 (8) 118 4.0
Benin 84 4 4 (5) 17 2.3
Ghana 82 37 4 (4) 10 0.4
Kenya 71 40 71 (90) 162 5.0
Mali 76 14 3 (5) 79 1.0
Rwanda 88 32 2 (5) 468 5.5
Tanzania 94 12
Uganda 87 29 29 (52) 126 3.2
Zambia 79 35 8 (11) 44 1.5
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Outbreak countries. AFR. 2006
Country Average MCV coverage (03 05) Interval b/n last SIAs and onset of outbreak (months) () districts involved Size of largest cluster (cases/ district) Confirmed measles Incidence rate
Angola 57 32 13 (8) 118 4.0








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Outbreak countries. AFR. 2006
Country Average MCV coverage (03 05) Interval b/n last SIAs and onset of outbreak (months) () districts involved Size of largest cluster (cases/ district) Confirmed measles Incidence rate


Ghana 82 37 4 (4) 10 0.4






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Outbreak countries. AFR. 2006
Country Average MCV coverage (03 05) Interval b/n last SIAs and onset of outbreak (months) () districts involved Size of largest cluster (cases/ district) Confirmed measles Incidence rate








Zambia 79 35 8 (11) 44 1.5
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Outbreak countries. AFR. 2006
Country Average MCV coverage (03 05) Interval b/n last SIAs and onset of outbreak (months) () districts involved Size of largest cluster (cases/ district) Confirmed measles Incidence rate



Kenya 71 40 71 (90) 162 5.0





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Trends of confirmed measles cases. Kenya. 2003
2006.
F-up SIAs done July 06
F-up SIAs postponed
Catch-up SIAs June 02
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Measles cases in Kenya. 2006
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Confirmed measles cases by age and vaccination
status. Kenya. 2006
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Outbreak countries. AFR. 2006
Country Average MCV coverage (03 05) Interval b/n last SIAs and onset of outbreak (months) () districts involved Size of largest cluster (cases/ district) Confirmed measles Incidence rate







Uganda 87 29 29 (52) 126 3.2

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Trends of confirmed measles cases. Uganda. 2002
2006.
F-up SIAs Nov 2006
Catch-up SIAs Oct 2003
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Measles cases in Uganda. 2006
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Confirmed measles cases by age and vaccination
status. Uganda. 2006
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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)

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Age distribution of measles cases. Dar es
Salaam, Tanzania July mid Oct. 2006
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Disturbing gaps in the quality of data
Country cases with age missing cases with vaccination status missing/ unknown
DRC 30 44
Ethiopia - 55
Kenya 4 55
Tanzania - 78
Uganda - 82
Ghana 14 41
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• Quality of surveillance
• Measles outbreaks in 2006
• Lessons learnt

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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

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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

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Thank you