The man also worked at that Kaffee Eis on Wednesday, October 5, the Kaffee Eis in Courtenay Place on Thursday, October 6 and Kaffee Eis in Cable Car Lane - a tourist attraction - on Friday, October 7.
"These locations are very popular and there is the potential that large numbers of people have been exposed to the infection," Dr Nesdale said.
"... over these days, Kaffee Eis was very busy."
The man also went to Les Mills Gym in Taranaki Street between six and 7.30pm on the Wednesday and from 4-6pm on the Thursday.
"We have been informed that approximately 2000 people attend the Les Mills Extreme Gym each day," Dr Nesdale said.
"We are working closely with the Les Mills Extreme Gym and Kaffee Eis to trace staff. However, ... tracing of customers and gym members is not possible.
"Anyone who was at these venues should check their immune status and if in doubt contact their doctor."
The man is the second Wellingtonian confirmed to have measles. Auckland is experiencing an epidemic.