Immunization, Vaccines and Biologicals

Data, statistics and graphics by subject

Disease incidence

Disease incidence is the principle measure of impact of the immunization system. Disease incidence data usually represent only a fraction of the cases, but are useful to monitor trends. Different countries adopt different surveillance systems resulting in variable quality and sensitivity of reporting. Therefore, incidence comparison among countries requires additional information on surveillance quality

Immunization coverage

Immunization coverage is a key measure of system performance and output

In most countries administrative coverage data are collected by monitoring the number of doses administered to the target population. This number is divided by the total estimated number in the target population to estimate % immunization coverage
Immunization coverage surveys are also recommended by WHO to be conducted periodically to verify administrative coverage data
WHO and UNICEF request from countries their best estimate of coverage (administrative or survey data) and this figure is reported as official coverage estimate

Based on the data available, consideration of potential biases, and contributions from local experts, WHO and UNICEF have attempted to determine the most likely true level of immunization coverage. Estimates of national immunization coverage were made for BCG, the third dose of diphtheria, tetanus and pertussis vaccine (DTP3), the third dose of polio vaccine (Pol3), the first dose of measles vaccine (MCV) and the third dose of hepatitis vaccine (HepB3). Since 2000, estimates have been done for the proportion of live births protected (PAB) through maternal immunization with at least 2 doses of tetanus toxoid for country where the risk of neonatal tetanus is a significant public health problem. In 2005 estimates of the first dose diphtheria and tetanus toxoid and pertussis vaccine (DTP1) and the third dose of haemophilus influenzae type b (Hib3) have also been added. In 2010 estimates for 3rd dose of pneumococcal conjugate vaccine, the last dose of rota virus vaccine (2nd or 3rd dose depending on the vaccine presentation) and first dose of yellow fever vaccine (YFV) were added

Immunization system indicators

Indicators of system performance and process are monitored in most countries. WHO and UNICEF collect information on planning and management, system performance, surveillance, policy, safety, finance, new vaccines introduction, maternal and neonatal tetanus (MNT) elimination, polio eradication, vitamin A, measles mortality reduction and yellow fever control

Immunization schedule

National immunization schedules are established to guide immunization staff at all levels. WHO recommends that all countries immunize against diphtheria, hepatitis B, measles, pertussis, poliomyelitis, and tetanus. Countries with a substantial burden due to haemophilus influenzae type B (Hib) are encouraged to introduce Hib vaccine into their national immunization schedule. Bacilles-Calmette Guerin (BCG) vaccine is recommended at birth in those countries with a high prevalence of tuberculosis (TB). Immunization against yellow fever is recommended in countries at risk for outbreaks. Immunization schedules vary by country and depend primarily on the local epidemiology of the vaccine-preventable disease and an ability to finance the vaccine

Supplementary immunization activities

Supplementary immunization activities (SIAs) are used to reach the population who has not been vaccinated or has not developed sufficient immunity after previous vaccinations


Last update:

3 April 2014 15:59 CEST