Three outbreaks of Pseudomonas dermatitis were associated with the use of whirlpool baths or hot tubs. In 1985, CDC personnel investigated four outbreaks of diarrheal illness on cruise ships calling at U.S. ports. Shrimp cocktail was implicated as the vehicle of illness. In July, on a 1-week Caribbean cruise out of St. Petersburg, at least 238 passengers suffered diarrhea and vomiting of generally short duration, but neither a disease agent nor a vehicle was identified. In December, at least 70 of 540 passengers on a transatlantic cruise docking in Miami reported gastrointestinal illness associated with a seafood cocktail, but no agent was identified as the cause of illness.
Some evidence suggests that an actual decrease in water-related diseases is occurring.
Active surveillance in some states reveals defects in water delivery systems, and as these are corrected, the potential for water-related disease outbreaks may be diminished. For 1984 and 1985 together, however, only three outbreaks were discovered in that state, despite both active and passive surveillance of water-related diseases. As other states begin to look for problems, they may also experience sudden increases in reported water-related diseases, followed by a decline in cases as identified problems are corrected. The smaller number of outbreaks reported in 1985 may be due, however, to less complete reporting rather than to an actual decrease in outbreaks. The waterborne disease surveillance system is largely passive.