How vaccines work: WHO information on immune memory and protection before exposure
WHO explains vaccination as a way of training the immune system to recognize specific infections and build protection before exposure to disease.
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Vaccination & Prevention
Parent Resources grouped in the Vaccination & Prevention category. Open an individual resource to see its cited sources and source-review date.
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Vaccination & Prevention Parent Resources
Only Parent Resources assigned to this Resource Category are shown here.
HPV vaccination in early adolescence: what WHO’s 2026 cervical-cancer information says
WHO identifies HPV vaccination in early adolescence as a central way to prevent persistent high-risk HPV infection and future cervical cancer.
Polio and children: WHO information on transmission, paralysis and global eradication progress
WHO information on poliovirus, why children under five are especially affected and how global eradication efforts have reduced wild-polio cases by more than 99%.
Global childhood immunization coverage in 2025: what WHO means by zero-dose children
WHO’s July 2026 immunization estimates, including global DTP coverage and the number of children receiving no routine vaccine in their first year.
Hepatitis B in infancy and childhood: WHO information on transmission and global progress
WHO information on hepatitis B transmission in early life and the changing global prevalence among children under five.
Vaccine safety: how WHO describes testing and monitoring before and after introduction
WHO information on vaccine testing, ongoing safety monitoring, adverse events following immunization and independent safety review.
Childhood vaccination in India: understanding the National Immunization Schedule
General information on how the current MoHFW National Immunization Schedule is structured and why the official schedule and vaccination record matter.