Health officials say there’s been an alarming increase in some dangerous superbugs at U.S. hospitals.

These superbugs are common germs that have become extremely resistant to treatment with antibiotics.

The number of hospitals reporting infections with these superbugs is still small. But a government report shows 1 in 25 hospitals saw at least one case last year.

The Centers for Disease Control and Prevention released the new tally Tuesday. They’re urging hospital workers to take steps to keep the germs from spreading.

The dangerous germs can cause pneumonia and urinary tract and bloodstream infections in vulnerable, hospitalized patients.