Why do some people think that smallpox and monkeypox are the same virus?
The usual suspects…
Are Smallpox and Monkeypox the Same Virus?
In this case, we have one of those situations in which having a little knowledge can be a dangerous thing…
Why?
Well, it turns out that smallpox and monkeypox (Mpox) are very closely related.
That’s not too surprising though, considering that they both are DNA viruses in the same Poxviridae family of Orthopoxvirus.
But how related?
“The nucleotide sequence within the central region of the MPV genome, which encodes essential enzymes and structural proteins, was 96.3% identical with that of variola (smallpox) virus (VAR).”
Human monkeypox and smallpox viruses: genomic comparison
Would you believe that they are 96.3% identical!
That’s pretty related.
Still, that doesn’t mean that they are the same virus.
After all, humans and chimpanzees are about 98.9% identical and that doesn’t mean that we are the same, right?
So, what does it mean?
Fortunately, it means that the similarities are in the right places so that the newest smallpox vaccine can protect against both smallpox and Mpox!
Again, though, they are different viruses.
They cause different diseases, even though both involve a similar ‘pox like’ rash.
What else?
Smallpox was eradicated by strictly quarantining anyone who was infected and vaccinating all of their contacts.
Smallpox was not just renamed to Mpox.
So the smallpox vaccine is actually a 2 in 1 vaccine!
Interesting.