I thought that CDC article was very interesting. However, I did not see any link or possible conclusion that suggests that cya is bad in this report.
In both cases listed in the report, the bacterial problems were caused by malfunctioning chlorine injection feeders... lack of disinfectant caused bacterial growth.
Poor monitoring increased potential for fatal results.

what it does say about Cya is:
" cyanuric acid, which is used to reduce chlorine loss as a result of ultraviolet light exposure, is not recommended for indoor pools or hot tubs and is prohibited in two states ; adding this chemical reduces the antimicrobial capacity of free chlorine. "

I'm not exactly sure what they mean by this ( & how this affects us)
" cya reduces antimicrobial capacity of free chlorine "
perhaps some of the chemistry majors here can explain farther the effects of this statement.


I also thought that these guidelines were pretty standard ( & worthwhile):

To reduce the risk for Pseudomonas dermatitis and the transmission of other waterborne pathogens, pool and hot tub operators should
1) adhere to pool and hot tub recommendations and regulatory requirements for pH and disinfectant levels;
2) have a thorough knowledge of basic aquatic facility operation;
3) provide training for pool staff on system capabilities, maintenance, and emergency alert procedures of remote monitoring systems;
4) closely monitor pool and hot tub free chlorine measurements during periods of heavy bather loading;
5) monitor hot tub disinfectant levels closely because the higher temperatures maintained serve to dissipate chlorine rapidly;
and 6) understand appropriate use and effects of cyanurates on disinfection and testing.
In addition, remote-monitoring companies should be timely in notifying swimming-facility staff about low disinfectant levels.
Swimmers should be educated about the potential for waterborne disease transmission in pools and hot tubs, which could increase advocacy for improved maintenance and monitoring by pool operators.