Japan's health ministry says the number of coronavirus cases are continuing to rise slowly nationwide.

The ministry says 54,150 cases were reported by about 5,000 medical institutions across the country in the seven-day period through July 16. That figure rose by 9,042 from the week before.

The average number of patients per institution was 11.04, up 21 percent from the previous week. This is the 15th straight week-on-week increase.

By prefecture, Okinawa has the highest average number of patients at 31.83 per institution, followed by Saga with 23.05 and Miyazaki with 20.79.

The average number increased in 43 of the country's 47 prefectures.

The ministry says 6,952 people were newly hospitalized during the week through July 16, an increase of 632 from the previous week.

The ministry says the number of COVID-19 cases are slowly rising nationwide with the pace of growth remaining almost flat.

It says some prefectures in the western regions of Kyushu, Chugoku and Shikoku are recording larger week-on-week increases.

The ministry is calling on prefectural governments to prepare for a possible spread of infections this summer through cooperation between medical institutions, and other means.