HONOLULU -- State health officials confirmed the highest number of swine flu, or H1N1 Influenza A, cases in a day on Thursday with seven new cases.

That raises the total number of H1N1 flu cases in Hawaii so far to 40.

Three of the patients are adults and four are children. One of the adults is a teacher at Mililani Middle School. One of the children is a student at Waiau Elementary School, officials said.

Letters informing parents went home with students on Thursday. The school said it has taken steps to keep the virus from spreading.

"We've been doing the precautionary measures wiping things down checking the bathrooms making sure they're clean. We've been informing and educating our staff and our students about things like covering your nose and mouth when you cough and sneeze," Waiau Elementary School Principal Troy Takazono said.

School officials said they had no information on how the student contracted the illness.

Two of the adults recently traveled to the mainland, the state said.

"None of the cases that have been picked up within the state have required hospitalization and all are recovering," Health Director Dr. Chiyome Fukino said.

Health officials said while the cases are not serious and many victims have fully recovered, there is much more work left to be done to contain the disease.

"If you have a temperature of 100 degrees or more and you are coughing and have a sore throat, you need to stay home from work," Fukino said.

The state is not closing schools where the disease is reported, because in order for school closures to work, students have to stay home, Fukino said. The students have not stayed home in many places on the mainland.

"Our older children go to the shopping malls, go to theaters and are actually congregating in much closer proximity than they do at school," Fukino said.

In the last 10 days, the number of Japanese visitors to Hawaii has dropped significantly because of the flu. Daily Japanese arrivals have gone down anywhere from 22 percent to 37 percent compared to year-ago numbers.

"Once those concerns go down a little bit, then we will be there with our travel partners and encouraging travel back to the islands," tourism liaison Marsha Wienert said.

While the Japanese travel slump hurts Waikiki and hotels statewide, Hawaii is not alone.

"We have seen the downturn or decrease in passenger travel from Japan in many different places in the world. It's not just Hawaii," Wienert said.

Tourism officials said even Guam, which has no cases of the swine flu, is experiencing a big loss in visitors from Japan.

Here is some good news. The flu has had no adverse impact on the number of tourists coming to Hawaii from the United States.