The World Immunization Week 2019 observed from 24-30th April. It's theme is;

The World Immunisation Week 2019 celebrates 'Vaccine Heroes' worldwide ranging from parents and community members to health workers and innovators who help to ensure that we are protected via the power of vaccines. The theme for 2019 is 'Protected Together: Vaccines Work'. The last week of April (24th-30th) every year is observed as World Immunisation Week in order to promote the use of vaccines for the protection of people of all age-groups against disease. The WHO (World Health Organization) notified that there are still 20 million unvaccinated and under-vaccinated children worldwide; so this initiative brings to limelight the necessity to bring on immunization progress through increased investment. Immunization Week was observed for the very first time in 2012 when more than 180 countries and territories worldwide participated in it.