1. Percentage point difference between DTP1 and DTP3
The difference between coverage of one dose of diphtheria-tetanus-pertussis (DTP1) and three doses (DTP3) in 73 Gavi eligible countries.
Drop out rates are a measure of the strength of a health and immunisation system, demonstrating its potential to reach children with the third dose in a series:
- strong health systems guarantee a sufficient number of contacts with children at appropriate times to ensure high coverage with three doses of DTP vaccine;
- weaker systems can reach a child with the first dose in the series, but not the third.
Targets are derived from an examination of historical data and the assumption that Gavi investments in health and immunisation systems strengthening can support countries to decrease their drop out rate by approximately half a percentage point per year.
Progress will be measured through WHO/UNICEF coverage estimates.
2. DTP3 coverage
The weighted average DTP3 coverage in 73 Gavi eligible countries.
DTP3 coverage is a frequently used indicator of the strength of immunisation and health systems for two reasons:
- delivery of DTP3 requires three contacts with the health system at appropriate times;
- DTP vaccine tends to be given through routine national immunisation programmes rather than campaigns.
DTP3 coverage is measured through WHO/UNICEF estimates. Primary sources used by the WHO/UNICEF estimates include country administrative data, household survey data and other sources as appropriate.
3. MCV1 coverage
The weighted average MCV1 coverage in 73 Gavi eligible countries.
Measles routine first dose coverage is measured through the WHO/UNICEF estimates, which are updated each year for every member state. Primary sources used by the WHO/UNICEF estimates include country administrative data, household survey data and other sources as appropriate. Estimates are weighted by country using estimates of surviving infants from the United Nations Population Division.
MCV1 coverage is measured through WHO/UNICEF estimates. Primary sources used by the WHO/UNICEF estimates include country administrative data, household survey data and other sources as appropriate.
4. Equity in immunisation coverage
Proportion of Gavi supported countries where DTP3 coverage in the lowest wealth quintile is not more than 20 percentage points lower than coverage in the highest wealth quintile.
Although global access to vaccines has become more equitable, internal disparities in immunisation coverage persist in a large majority of countries. The most consistent is between the poor and the non-poor.
Children in poor households have a substantially greater risk of dying from vaccine preventable diseases than children born in relatively better off households.
As of 2010, more than half of Gavi eligible countries with available survey data had a discrepancy of more than 20 percentage points between DTP3 coverage in the poorest wealth quintile and DTP3 coverage in the least poor quintile.
To calculate this indicator, the difference is measured between DTP3 coverage in the poorest wealth quintile and DTP3 coverage in the least poor quintile. Then, the proportion of the 73 Gavi eligible countries that have a difference of less than or equal to 20 percentage points between these two wealth quintiles is tracked.
Gavi uses the latest available household survey data from each Gavi eligible country; where Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS) are not available, other surveys that use comparable methodologies are used in their place.