Emergency services say the patients were all stung multiple times.
IPSS Medical Rescue's Paul Herbst says two people had serious reactions to the stings.
"Several of the employees were severely stung multiple times. Two people sustained extensive critical injuries due to anaphylaxis," he said.
Herbst says no one else was hurt.
Whether your main choice of exercise is running, cycling, swimming, tria...East Coast Drive with Bongani and Mags 7 hours ago
Bongani has a dilemma. A friend of his bought him a gift of designer sho...East Coast Drive with Bongani and Mags 9 hours ago