Teach them some math(s)

I decided to watch Contagion on the telly the other night.  I thought it might be fun to see how Hollywood's idea of a pandemic matched reality....  Anyway, can you spot the glaring mistake in this clip?

That's right!  He said math when he should have said maths.  Math ith a roman catholic thervith!

There was another problem too.... In the exponential phase the numbers infected increases by the same factor each day, rather than squaring each day.  Or to put it another way, the sequence should have been
$$
x_n = 2^n
$$
and not what he said, which was
$$
x_n = 2^{2^{n-1}}
$$

Dear Hollywood, I am happy to offer my services as on set math(s) consultant.  I am very cheap.