ANALYSIS: A vaccine can provide better immunity than an actual infection. Here's why.

Vaccines have other advantages over natural infections. For one, they can be designed to focus the immune system against specific antigens that elicit better responses.

 

For instance, the human papillomavirus (HPV) vaccine elicits a stronger immune response than infection by the virus itself. One reason for this is that the vaccine contains high concentrations of a viral coat protein, more than what would occur in a natural infection. This triggers strongly neutralizing antibodies, making the vaccine very effective at preventing infection.

 

The natural immunity against HPV is especially weak, as the virus uses various tactics to evade the host immune system. Many viruses, including HPV, have proteins that block the immune response or simply lie low to avoid detection. Indeed, a vaccine that provides accessible antigens in the absence of these other proteins may allow us to control the response in a way that a natural infection does not. ...