Immunization coverage among 1-years-olds

- with one dose of measles (percentage)
- with three doses of diphtheria, tetanus toxoid and pertussis (DTP3) (percentage)
- with three doses of Hepatitis B (HepB3 ) (percentage)

Rationale for use

Immunization coverage estimates are used to monitor immunization services, to guide disease eradication and elimination efforts, and are a good indicator of health system performance.

Definition

Measles immunization coverage is the percentage of one-year-olds who have received at least one dose of measles containing vaccine in a given year. For countries recommending the first dose of measles among children older than 12 months of age, the indicator is calculated as the proportion of children less than 24 months of age receiving one dose of measles containing vaccine.

DTP3 immunization coverage is the percentage of one-year-olds who have received three doses of, the combined diphtheria and tetanus toxoid and pertussis vaccine in a given year.

HepB3 immunization coverage is the percentage of one-year-olds who have received three doses of Hepatitis B3 vaccine in a given year.

Data sources

Administrative data: Reports of vaccinations performed by service providers are used for estimates based on administrative data service providers (e.g. district health centres, vaccination teams, physicians). The estimate of immunization coverage is derived by dividing the total number of vaccinations given by the number of children in the target population, often based on census projections.

Household surveys: Survey items correspond to children’s history in coverage surveys. The principle types of surveys are the Expanded Programme on Immunization (EPI) 30-cluster survey, the UNICEF Multiple Indicator Cluster Survey (MICS), and the Demographic and Health Survey (DHS).

Methods of estimation

WHO and UNICEF rely on reports from countries, household surveys and other sources such as research studies. Both organizations have developed common review process and estimation methodologies. Draft estimates are made, reviewed by country and external experts and then finalized.

Disaggregation

By sex, location (urban/rural, major regions/provinces), and socio-economic characteristics (e.g. mother’s education level, wealth quintile).

References

Database

Comments

The principle challenges are to improve the quality (accuracy, validity, completeness and timeliness) of the data. Also, interpretation of available data needs to be improved by adjusting for possible biases for the most accurate estimate of immunization coverage possible.