Encyclopedia of Opinion

Question: Are vaccines safe?
Position1 of 3›: Vaccines are safe
Argument1 of 4›: Vaccines cause herd immunity

Vaccines protect those who haven't or can't been immunised through herd immunity.

The argument

The World Health Organization (WHO) estimates that immunisation averts 2-3 million deaths worldwide each year. Vaccines don’t just save the lives of the children vaccinated. They save the lives of those who are not vaccinated by ensuring pathogens cannot spread quickly across the population. This is called herd immunity. Immunisation aims to protect the individual against a disease. It also makes that person less likely to be a source of infection to others so protecting those that are not immunised as it stops the germs responsible for infections being transmitted between people. A significant number of the population need to be immunised to offer herd immunity – this number depends upon how infectious the disease is. Children with weakened immune systems due other diseases or medications they are taking are not recommended to be immunised. These included lung, heart, liver, kidney disease or diabetes. Newborn babies are deemed too young to be immunised. Children receiving chemotherapy for cancer are not offered immunisations due to their weakened immune system. Measles has a 50% death rate for children with a weakened immune system so the importance of herd immunity can be seen here to protect vulnerable children who are unable to be immunised.

Context

For accurate information on the efficiency of vaccines, consult the WHO website.

Premises

[P1]Vaccines protect not only those immunised but also reduce transmission of pathogens across the population, creating herd immunity. [P2] Herd immunity is essential to protect vulnerable groups—such as newborns, the immunocompromised, and chemotherapy patients—who cannot themselves be vaccinated. [P3] The WHO estimates immunisation averts 2-3 million deaths annually, demonstrating that vaccines reliably deliver these protective benefits without undue harm. [C] Therefore, vaccines are safe and beneficial because they secure herd immunity that safeguards both the vaccinated and the vulnerable.

Counter-arguments

Herd immunity speaks to how well vaccines work at the population level, not to whether they are safe for the individual receiving them. That immunisation prevents millions of deaths and shields the vulnerable is a claim about efficacy and benefit; it does not by itself address adverse effects or individual risk, which is what the question of safety asks. One could grant every point about herd immunity and still be raising a separate question about a given vaccine's side-effect profile. The argument therefore establishes that vaccines are beneficial, not, strictly, that they are safe.

Rejecting the premises

[Rejecting C] Demonstrating population-level benefit through herd immunity is a distinct claim from demonstrating individual safety; the former does not entail the latter.