Some people de-worm every year -- I did mine last year when they were molting, just before winter. It is recommended to not eat the eggs for something like 10 days to 2 weeks after they've been given the worming medicine. Since they aren't laying during a molt anyway and they slow down laying in winter, it seemed to me the most sensible time to worm them.
I vaccinate mine for Marek's immediately after they hatch. Some say to not feed medicated feed if they've been vaccinated -- but the vaccine is against Marek's and the medicated feed is against cocci... so I don't see what one has to do with the other.
How old are your pullet's? In Florida your hens may not noticeably slow down laying like they do here in Ohio where winter's can be cold and dreary. But they should molt which affects egg production.
Jenny