Dr Celi was an infectious diseases and intensive care unit specialist at Dunedin Hospital from 2002-07.
He is now a staff member at the Harvard Medical School, Boston, and also works at the Beth Israel Deaconess Medical Centre Intensive Care Unit.
Dr Celi was a keynote speaker at the New Zealand Nurses Organisation National Division of Infection Control Nurses Conference, which ended in Dunedin yesterday.
About 170 people attended.
He gave a talk on Thursday on "creating a culture of quality and safety" to reduce hospital-acquired infections.
About 99,000 people died in the United States each year - amounting to 275 people a day - from such infections.
New Zealand's rate of hospital-acquired infection - 11% - was generally similar to that of other developed countries, he said.
Persistently high rates of such infections showed that traditional approaches to prevention had failed.
It was a complex problem, "requiring social and behavioural change".
Hospital staff were competent and caring but could be "trapped in a bad system".
A new approach was needed, focusing more on patients and less on the convenience for doctors, he said.
Parts of the doctor's traditional white coat, including the cuffs, and the dangling long tie, could transmit disease between patients, he said in an interview.
A short-sleeved shirt and bow tie were better alternatives.
Altering medical rounds, so that doctors visited hospital patients with infectious diseases last, rather than before seeing other patients, was another effective move.
A behavioural and social change strategy, known as "Positive Deviance", had significantly reduced hospital-acquired infections at the VA Pittsburgh Healthcare System in Pennsylvania.
