Coming straight to the answer, it is not vaccines, rather a vaccination that saves lives. It essentially means that mandatory vaccination can save a large number of lives.

Vaccination fear or hesitance is widely prevalent in some nations. In addition, due to the spread of fake news, conspiracy theories, things are being made worse. Modern technologies like the internet are only helping spread these false notions.

It is almost impossible to calculate how many lives vaccines can save. It is because many highly contagious and life-threatening infections have been almost eradicated from the face of the earth with the help of vaccines.

Vaccination saves lives?

WHO thinks that vaccines save 2-3 million lives each year.  However, this is an extremely low and conservative estimate. It does not take into calculation the diseases that have been eradicated or largely overcome by vaccines. Just take the example of smallpox. It used to kill millions in the 19^th century. Some experts believe that if this disease was not eradicated, it would have been causing about 5 million deaths each year. It means that in the last 40 years, about 200 million lives have been saved from smallpox alone.

Just look at the data above (the data in figure 1 is for the US alone, not global). It shows how the prevalence of some diseases has come down by more than 90% due to vaccination. However, it is worth noticing that this comparison is not perfect, as these vaccines were widely available in the 20^th century, and the only thing that has changed since then is the vaccination rate. Now, even developing nations are vaccinating their population.

However, if data had been available for the 19th century, comparing it with the 21st century would have been a real eye-opener for vaccine skeptics.

Covid-19 vaccine hesitancy and its threat to global well-being

Generally, most who do not vaccine have two grounds, either belief in conspiracy theories fueled by anti-vaccine groups, or some consider mandatory vaccination a threat to their personal freedom to make choices.

Many people are worried, as they think that vaccines might cause some severe disease, while others believe that most would die after vaccination. Furthermore, some people believe that vaccines have chips that would enable governments to trace them. Additionally, a small number of people consider mandatory vaccination as a threat to their freedom.

However, data clearly shows few things. Firstly, covid-19 is highly contagious, and it cannot be eradicated or controlled until or unless the majority of the population is vaccinated. Secondly, the incidence of the disease is now much lower at places where most people are vaccinated.

This difference can be clearly seen between Western Europe and Eastern Europe. Just two different sides of the same continent. Vaccine skepticism is much higher in the East, and thus the incidence and prevalence of the disease.

To conclude, though making any vaccine mandatory will always remain controversial and met with a certain resistance. Nonetheless, the only way to overcome some diseases is through widespread vaccination. It is always better if it happens voluntarily.