Japan has extended its coronavirus state of emergency in many parts of the country, including Tokyo and Osaka, through the end of this month.
The extension came into force on Monday, in 19 of the nation's 47 prefectures.
Eight prefectures are under a quasi-state of emergency. The government is calling on people in the areas to stay home as much as possible.
Kindai University in Osaka began a new semester on Monday.
Due to the extension of the emergency, most class lectures are being conducted online. Not all students are happy.
One of them said, " didn't enter college to take classes through a display. I hope things will go back to normal so I can meet and talk with friends."
The number of new cases has been declining.
Authorities across Japan confirmed 4,171 infections on Monday, over 4,000 fewer than a week ago.
But the medical system remains under strain.
Nearly 2,000 patients across Japan are in serious condition.
At a hospital near Tokyo, 34 hospital beds are allocated for severe coronavirus cases. Twenty-five to 30 of them have been continuously occupied this month.
The government hopes vaccination will help improve the situation.
More than half of the country's population have now received two shots.
The western city of Toyonaka has started sending a doctor and a nurse in a camping car to administer vaccines.
Forty-eight people received a jab in the car when it parked at a temple.
A woman with her baby said, "I even hesitate to take a train, so I appreciate their coming to our community."
A high school student said, "I decided to be vaccinated so I can go on a trip with my friends."
The virus has mutated to become more contagious.
A Japanese company conducting PCR tests says it found that the amount of virus detected from a patient infected with the Delta variant is at least four times higher than the original strain.
A member of the Japanese government's expert panel warns a patient's throat and saliva contain large amounts of the virus.
Toho University Professor Tateda Kazuhiro said, "A considerable amount of virus is contained in tiny droplets dispersed in a very short conversation."
He is calling on people to wear non-woven fabric face masks and to ventilate rooms.