Nagoya City Hall (Mainichi/Hiroki Sameshima)

NAGOYA -- A novel coronavirus cluster centered on a gym in this central Japan city is subsiding, according to municipal officials, suggesting that it was easy to trace those who had potentially been exposed.

The cluster was one of two that have emerged in Nagoya.

"As the gym has a membership system, we could identify customers' names and the times they entered and left the facility, and thus swiftly identify people who needed health monitoring," a city official said.

A gym customer in her 60s was found infected with the novel virus strain on Feb. 15, and the virus apparently spread primarily among customers and others connected with the facility. By March 11, a total of 38 people in the cluster, including the woman, had been confirmed infected, according to the Aichi Prefectural Government.

At least one family member of an infected person in the cluster was confirmed to carry the virus on March 10. However, no new infections have been found among those directly linked to the gym over the past two weeks.

Kiyofumi Asai, a medical expert in the city's health and welfare bureau, told reporters on March 12, "I think the cluster is on course to waning, although we need to maintain vigilance."

Meanwhile, the other cluster in the city, which spread through welfare facilities including a day nursing center for the elderly, is apparently expanding.

Asai pointed to the difficulty in tracking down people linked to this cluster, as their movements are complex and wide-ranging, and numerous people need to be monitored.

"This coming week will be the turning point for whether we can curb the increase in infections. We need to track the effect of our measures closely, including health monitoring," he said.

(Japanese original by Ayuko Nomura, Nagoya News Department)