(Portland, OR)  --  An elementary school near Astoria remains closed today due to an outbreak of the flu.  Officials at Hilda Lahti Elementary School in Knappa cancelled classes yesterday and today for kindergartners through sixth-graders.  School officials say about 43-percent of their students have contracted the flu so far, as well as several teachers and staff members.  Superintendent Paulette Johnson tells the Daily Astorian that some classes Monday were down to just four healthy students.