For 200 years scientists have developed new vaccines that have dramatically lowered infection rates and saved millions of lives from premature death due to communicable diseases. The HPV vaccine is a newer vaccine (2003) that provides almost 100% protection from several HPV types. Although traditionally administered as a shot, some new vaccinations are administered in ways other than shots, but their effectiveness is questionable. For example, one anti-flu nasal spray claims to be an effective vaccine, but recent research studies have demonstrated that it most likely does not provide any measurable protection against the flu virus.

Question

For 200 years scientists have developed new vaccines that have dramatically lowered infection rates and saved millions of lives from premature death due to communicable diseases. The HPV vaccine is a newer vaccine (2003) that provides almost 100% protection from several HPV types. Although traditionally administered as a shot, some new vaccinations are administered in ways other than shots, but their effectiveness is questionable. For example, one anti-flu nasal spray claims to be an effective vaccine, but recent research studies have demonstrated that it most likely does not provide any measurable protection against the flu virus.

Imagine that for the past several years, the oldest child of a family received the anti-flu nasal spray, even though all of his classmates and the rest of the family received flu shots. None of the family members became infected with the flu during this time. The fact that the oldest child got the nasal spray and never got the flu demonstrates which of the following?
scientific evidence
causation
herd immunity
real science

Answer 1