Medical clinics and emergency rooms across Oahu are now grappling with an upsurge in flu cases — and one strain appears to be particularly tough. A flu shot may be only 10 percent effective against the strain known as the H3N2 virus; still, a lightweight shield is better than none at all.

State Department of Health officials are urging a shot for everyone older than 6 months. Back up that prevention effort with frequent hand-washing, cover your mouth when coughing or sneezing, and, should you get sick, stay home while recovering.

Pay attention to that restaurant placard

When visiting your favorite restaurant, make it a point to check out the state Health Department inspection placard on display there. Green means the eatery complies with food safety requirements. Yellow means violations need to be corrected. Red means go eat somewhere else.

The department recently issued a $13,000 fine to Sam Choy’s Kai Lanai restaurant in Kailua-Kona, saying that an employee had replaced its yellow placard with an old green one. The fine is the latest high-profile reminder that the Health Department takes this program very seriously. So should restaurants, and so should consumers.