One problem with vaccines that contain killed pathogens is that
A the pathogen may reactivate and cause disease.
B they may stimulate an excessive immune response.
C they may not stimulate a strong response.
D they cannot be given to immunocompromised people.
E they can only be given to immunocompromised people.
The correct answer and explanation is :
The correct answer is:
C. they may not stimulate a strong response.
Explanation:
Vaccines are designed to trigger the immune system to recognize and respond to specific pathogens, without causing the actual disease. One type of vaccine is a killed pathogen vaccine, where the pathogen is inactivated or killed through methods like heat or chemicals. This kills the pathogen, but it retains the ability to stimulate the immune system to produce an immune response.
However, one drawback of killed pathogen vaccines is that they may not stimulate a strong immune response compared to live (attenuated) vaccines. This is because when a pathogen is killed or inactivated, it may lose some of the components that are important for a robust immune reaction, such as the pathogen’s ability to replicate and trigger a sustained immune response.
In live (attenuated) vaccines, the weakened pathogen is still alive but unable to cause disease. It tends to provoke a more vigorous immune reaction because the immune system detects the pathogen as if it were a natural infection. On the other hand, killed pathogens are often unable to reproduce, and as a result, they may not activate the immune system as strongly. This can lead to a weaker immune response, which may mean that additional booster shots are required to maintain immunity.
Other issues related to killed pathogen vaccines:
- Option A (the pathogen may reactivate and cause disease) is more relevant to live vaccines, not killed ones, since the pathogen in killed vaccines cannot replicate or cause disease.
- Option B (they may stimulate an excessive immune response) is unlikely, as killed vaccines are typically less likely to cause an overactive immune response compared to live vaccines.
- Option D (they cannot be given to immunocompromised people) is incorrect. In fact, killed pathogen vaccines are usually safe for immunocompromised individuals because they do not contain live organisms.
- Option E (they can only be given to immunocompromised people) is also incorrect. Killed vaccines can be given to a broad population, not just those who are immunocompromised.
Thus, the main issue with killed pathogen vaccines is their potentially weaker immune response (Choice C).