The person may understandably ask:
“How can this happen if I was vaccinated?”
It can happen because vaccines are not designed to provide perfect protection against every infection
forever.
The immune system is complicated. Protection can change over time, viruses evolve, and individual immune responses differ.
The WHO explains that protection against severe COVID-19 and death is highest during the first months after vaccination and then decreases over time. Immunity can also decline after infection, which is one reason health authorities periodically reassess vaccination recommendations.
That means someone who was vaccinated previously may not have exactly the same level of protection months or years later.
And the virus itself has changed.
What Is a Breakthrough Infection?
A breakthrough
infection simply means that a person becomes infected despite having received vaccination.
It does not automatically mean the vaccine failed.
In fact, breakthrough infections are expected with many vaccines, especially vaccines whose primary benefit is reducing the severity of disease rather than completely blocking infection.
