What is the difference between an atteuated vaccine and a killed vaccine?

Answer 1

There are 2 types of vaccines:

(1) Live ("attenuated", or bred to be harmless)

(2) Killed (dead disease-causing particles)

Live vaccines can be more effective, don't usually need 'booster' shots later to make them work better, but are less able to be given to immunocompromised or pregnant people as they are still alive.

Killed vaccines are less effective, often requiring boosters, but can be given to immunocompromised people and (often) pregnant ladies. They are used with an "adjuvant", or a substance that helps them work better (makes your body more able to make antibodies to them faster).

Both types of vaccines have 'epitopes', or molecules that your body recognises. These epitopes are the SAME as what is on the actual disease-causing particles. This is why they work - your body sees the "HARMLESS" particles and learns to recognise them, or creates "antibodies" that help your body respond to the actual thing when it appears.

It takes time to create these antibodies, so if you can make them BEFORE the actual disease finds its way into your body, you can respond much faster and destroy the virus particles before they can cause you harm.

The type of vaccine depends on what has been developed. There are benefits of both ways, but it is not always easy to do both.

Side note: occasionally, you will hear about how "vaccines are horrible, and cause more harm than good". Most of the time, people use multi-resistant organisms as examples, however, these organisms become resistant to ANTIBIOTICS, and NOT vaccines! Having antibodies is natural, unlike many antibiotics! They are NOT comparable! Antibodies are a post-infection method of disease control, whereas vaccines prevent the disease from establishing. Thus, vaccines have in the past been used rather successfully to rid the world of several diseases! (Which we can ALL be extremely grateful for!!!!!)

Another poorly-used example was that of the smallpox vaccine causing many deaths. Reasons why this example is tragically misused is that it was the first-ever attempt at vaccination in recorded history (we no longer live in such an age where we must rely on random human-testing of live NON-attenuated pathogen injection!). Smallpox protection included injecting pus from the lesions of an infected person (or another vaccinated person) to create antibodies.

Case in point: we no longer inject pus into people... it's a good way to spread other infections, and is less reliable in results. We no longer live in the 'dark ages' of immunology. The first attempts at reaching space failed badly, and yet nobody seems to be boycotting space travel now that science and technology has improved, so please be open-minded if anyone ever tells you that in vaccines, in general, are "bad". Okay? :)