You can block it. The unit won't heat or cool that room anymore though. The return air does effect supply air temp. And heat pump efficiency. With a 60 degree return air temp, the heat pump is more efficient then with a 70 degree return air temp.
We are simply getting contaminated causing otherwise healthy folks to lose the function of their kidneys and for a senior citizen who is already suffering sarcopenia this can be a death sentence because of the complexities associated with Renal Failure.
A. suum is found primarily in pigs, but infections in humans can cause significant pathology. If a human ingests eggs of A. suum, the larvae migrate to the lungs and die. (Adult worms of this species do not develop in the human intestine.) This can cause a particularly serious form of Ascaris pneumonia.