The results are undeniable: Australia and New Zealand have squashed the curve. Australia, a nation of 25 million people that had been on track for 153,000 cases by Easter, has recorded a total of 6,670 infections and 78 deaths. It has a daily growth rate of less than 1 percent, with per capita testing among the highest in the world.

New Zealand’s own daily growth rate, after soaring in March, is also below 1 percent, with 1,456 confirmed cases and 17 deaths. It has just 361 active cases in a country of five million.

These figures put the two countries closer to Taiwan and South Korea, which have controlled the virus’s spread for now, than to the United States and Europe — even places seen as success stories, like Germany.

It all started with scientists. In Australia, as soon as China released the genetic code for the coronavirus in early January, pathologists in public health laboratories started sharing plans for tests. In every state and territory, they jumped ahead of politicians.

“It meant we could have a test up and running quickly that was reasonably comparable everywhere,” Dr. Collignon said.

The government then opened the budgetary floodgates to support suffering workers and add health care capacity. When infections started climbing, many of the labs and hospitals hired second and third rounds of scientists to help.