SOUTH BEND — When the University of Notre Dame had returning students tested for the coronavirus before allowing them back on campus for the fall semester, just 33 — fewer than half a percent — of the nearly 12,000 tests came back positive.

But in the one-week span from Aug. 6 to Friday, the university has reported 29 cases of COVID-19. Of the 348 tests conducted since Aug. 3, more than 8% have been positive.

On Friday alone, the university reported 10 new cases. Of the 348 tests, 160 were performed on students and staff members with the football program. Many of the other tests were conducted on students who were either symptomatic or potentially had contact with symptomatic students.

And the numbers grew only worse over the weekend. Saturday, 3 of 11 tests came back positive, for a 27.3% positive rate. Sunday saw 15 new infections out of only 30 tests.