The rheumatic fever rate has dropped significantly with 98 people hospitalised last year compared with 177 in 2012, the Government says.
Health Minister Jonathan Coleman says that's a 45 percent reduction, while rates for Maori are down by 54 percent over the same period.
The rate for Pacific people fell by 27 percent.
"Rheumatic fever is a serious, preventable disease which usually starts with a sore throat and can lead to lifelong heart problems," he said today.
"It's encouraging to see this latest significant drop in rheumatic fever rates which continues the downward trend since 2013."
Dr Coleman says the health sector has worked hard, particularly in communities most at risk.
More than half the national reduction was in Northland and Counties Manukau district health boards.
The Government's target is to reduce rheumatic fever rates by two-thirds by the end of June 2017.
Measures put in place to tackle rheumatic fever include: