HONOLULU -- The Hawaii Department of Health on Friday listed six new confirmed cases of the swine flu, also known as H1N1 Influenza A. All of them are children, including an infant, officials said.

Two are at Ewa Elementary School, two are at Anuenue Hawaiian immersion school (bringing their total to five), one is a preschool-age child who is not attending a preschool and one is an infant.

The children at Ewa Elementary School and the infant contracted the illness from the two at Anuenue School who are family members, health officials said.

At Anuenue on Friday, the school's principal was busy trying to reassure parents the campus is safe.

The latest numbers bring the total cases in the state to 21.

Anuenue School is taking extra precautions because it is a school that prepares meals for other schools.

"We're doing everything we can to make the campus safe and clean and sanitary," Anuenue School Principal Charles Naumu said.

Janitors are working with extra effort to clean the school, Naumu said. The school is stressing healthy hygiene practices among students and staff.

That has not not eased the concern of families of students with whom KITV spoke.

Anuenue in Palolo Valley has the most confirmed cases of the H1N1 flu in any school, a total of five, one adult and four children.

A little more than 100 students did not attend class Friday. That is nearly half of the student body.

Families are being told they can keep their child home if they choose. It is an option more parents are apparently weighing.

It is still not clear how the outbreak began at the school, health officials said.

Department of Education officials confirmed Thursday that students at Mililani Middle School and Aina Haina Elementary School are H1N1 flu patients.