Vaccines

Vaccines

To the tune of “All I Want for Christmas is You” by Mariah Carey

[Verse 1] 
A vaccination can leverage
An inherent property
Of the human immune system
That being immune memory
The secondary response
To a pathogen is more strong
Faster and higher quality
Makes higher affinity antibodies

[Verse 2]
Active vaccines will deliver
A pathogen in altered form
The individual will develop
An immune response of their own
In contrast to passive vaccines
Where things like antibodies
And products of the immune response
Are delivered directly

[Chorus]
Vaccines are given before
Pathogen exposure
This is prophylactically
To help prevent severe disease
In individuals

[Verse 3]
An effective vaccination
Has several requirements
Must elicit a protective
Response in populations
This protective immune response
Must be somehow be measurable
The correlate of protection
Is what this measure is called

[Chorus]
Must also consider safety
Few side effects and no disease
There must be generation
Of long-lasting protection
And other considerations

[Bridge]
The stages of vaccine development
Include pre-clinical and several human phases
In every single phase
We must check that it is safe
Phase III is hard since there must be high levels of circulating disease

[Verse 4]
Vaccines with dead pathogens
Are known as inactivated
But those with a weakened virus
Are attenuated

[Chorus] 
But with new technology
There are new types of vaccines
Such as subunit
Or replication competent
Viral vectors

[Outro] 
A conserved region is the best vaccine target
A conserved region is the best vaccine target
A conserved region is the best vaccine target
A conserved region is the best vaccine target