Parvovirus can spread in blood (viremia) to bone marrow. It is detected in some stages of infection in Cerebrospinal fluid (CSF). However, I am thinking if it can spread directly with facilitated diffusion from capillaries to brain stem $\to$ and again to brain stem and finally to CSF; actually, I have this kind of diffusion in mind [Costanzo, Physiology, 5ed]
which is very rapid where I think the virus can travel with CO₂, since it is very small virus; the smallest DNA virus; 18-26 nm in diameter. I see no reason why Parvovirus cannot spread to CSF rapidly after viremia. This kind of spreading to CSF may be even faster than to the bone marrow where it lyses the erythroid precursor cells (EPCs); I do not know how fast this virus can cause in CSF, since there is no EPCs.
What are the possible symptoms of Parvovirus B19 in CSF?