Solution
= Solution
By <Bayes' theorem>, the required <conditional probability> is
$$
\boxed{P(G\mid+)=\frac{P(+\mid G)P(G)}{P(+)}=\frac{0.00099}{0.05094}=0.0194\quad\text{(3 s.f.)}.}
$$
This is about $1.94\%$; it is a different conditioning direction from the test's $99\%$ positive probability among carriers.