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World Immunization Week

World Immunization Week 2022 is celebrated on 24–30 April. It highlights the collective action needed and promotes the use of vaccines to protect people of all ages against disease. Get vaccinated! Don't let viruses and other germs get in the way of life's glorious moments! #LongLifeForAll

How much do you know about vaccines?

Take a quiz on immunization

🌍 It’s World Immunization Week! Celebrate with WHO’s new Kahoot! quiz, where you can learn how vaccines help keep us healthy and create #LongLifeForAll 👇

A brief history of vaccines

History of the smallpox vaccine

One of the deadliest diseases known to humans, smallpox remains the only human disease to have been eradicated. Many believe this achievement to be the most significant milestone in global public health.

History of the measles vaccine

Because measles has such a high infectivity rate, the threshold for community protection is also very high, requiring at least 95% immunity among the population to prevent epidemics. The failure to maintain very high rates of immunization can result in outbreaks when the disease is reintroduced.

History of the polio vaccine

Polio is a highly infectious disease, mostly affecting young children, that attacks the nervous system and can lead to spinal and respiratory paralysis, and in some cases death. Polio has existed since prehistoric times.

History of the influenza vaccine

Efforts to track the evolution and emergence of flu viruses continue today, and scientists monitor both seasonal and potentially pandemic flu strains. Because new strains appear frequently, the seasonal flu vaccine usually changes each year.

Other hot topics

Innovate to eliminate

How do you design a malaria elimination programme for hard-to-reach communities who already have difficulty accessing health care? National Malaria Programmes in Cambodia and Lao People's Democratic Republic are leveraging local know-how of village malaria workers to educate communities about malaria risks and encourage prevention.

Donate for health response in Ukraine

WHO is working night and day to help with the escalating humanitarian health crisis, but more funding is needed for WHO to provide critical medical supplies and expertise to help people with lifesaving healthcare. You can help!