The state's total burden of ED visits and disease syndromes, to include those hospitals not participating in HEDSS, is unknown.
An important factor for success of HEDSS was the commitment for statewide hospital participation.
Although HEDSS is simple conceptually, generation of compatible datasets from different entities for merging is difficult.
HEDSS might be useful to identify individual cases of disease syndromes of interest during investigation of possible outbreaks.
Every report of adult onset chickenpox is followed by a CDPH case investigation, including cases identified by HEDSS.