i had a virus with my maypop last year.
think it came from so many caterpillar -Gulf-frits
had a ton of them.

check water also.
if the ground stays too damp, it will make it worse.
they can dry out pretty good before any damage.

It looks like my maypops are beating the virus. When they had the full infection going on they didn't make any flower buds or tendrils. Now they are growing rapidly again and making both buds/tendrils and the new growth doesn't look sick. Fingers crossed it is over.