OKLAHOMA CITY — Coronavirus cases in Tulsa have been rising but officials say it’s too early to directly link the increase to a June 20 campaign rally held there by President Donald Trump.

The county has reported more than 1,300 confirmed cases of the virus in the 11 days since the rally drew about 6,200 people to a sports arena.

“Frankly (we) probably won’t see until next week just because of the lag from symptoms to testing to reporting,” Bruce Dart, the director of the Tulsa Health Department, said Thursday.

The incubation period for the virus is two to 14 days. Dart said previously health officials would be watching closely for six weeks for infections linked to the weekend of the president’s rally.

Dart said the increase has so far been traced to smaller gatherings such as at bars, gyms, restaurants, weddings and funerals. The Oklahoma State Department of Health on Thursday said there are a reported 14,539 cases statewide.