Del Mar will not race from Friday through Sunday this weekend after 15 jockeys tested positive for the coronavirus in tests conducted Tuesday, the track said in a statement released Wednesday afternoon. Joe Harper, the track’s chief executive officer, said racing will resume July 24. “Canceling this weekend’s races will give us additional time to monitor the situation and give the individuals who tested positive additional time to recover,” Harper said in the track’s statement. The jockeys were tested by the San Diego County Health and Human Services Agency at the request of Del Mar officials. The riders are believed to be asymptomatic and will quarantine for 10 days. “Assuming these individuals continue to show no symptoms, they will be isolated for a total of 10 days and should be able to resume their usual activities, including riding after that time,” Dr. Eric McDonald, the medical director of epidemiology and immunizations services for San Diego County, said in the track’s statement. The names of the jockeys who tested positive were not immediately available, but Umberto Rispoli, who won seven races on the track’s opening weekend from July 10 through Sunday, said in a message on Twitter that he was positive and asymptomatic. The track said that contact tracing of the affected riders has started. The tests were ordered after prominent jockeys Victor Espinoza and Flavien Prat tested positive for coronavirus last weekend. When racing does resume, jockeys from racing circuits outside of California will not be permitted to ride at Del Mar, the track said. In addition, jockeys based at Del Mar who leave to ride at other venues will not be permitted to ride at Del Mar through the conclusion of the summer meeting on Sept. 7. The track plans to expand the jockey’s quarters when racing does resume. Similar policies have been enacted at other tracks, notably Saratoga Race Course in New York. This weekend, the track was scheduled to run two Grade 2 races – the $150,000 San Diego Handicap on Saturday and the $200,000 Eddie Read Stakes on Sunday. Those races will be rescheduled for the weekend of July 25-26. The cancellation of racing is the latest setback in a summer meeting that has been disrupted by the coronavirus outbreak. The track was scheduled to run five days a week, but is operating on a Friday-through-Sunday basis for most of the meeting, which runs through Sept. 7. The meeting is being held without ontrack customers and with a limited number of employees on-site. Without the normal amount of ontrack handle, overnight purses were cut 20 percent before the start of the meeting and a majority of stakes are being run at lower purse levels than the corresponding meeting in 2019. Del Mar had drawn a nine-race program for Friday and 11 races for Saturday, including what was to be the California debut of Maximum Security, the champion 3-year-old male of 2019, in the San Diego Handicap. The coronavirus has affected all tracks in Southern California this year. The Santa Anita winter-spring meeting was disrupted from late March to mid-May after the Los Angeles County Department of Public Health ordered the track closed at the start of the pandemic after the racetrack was classified as a nonessential business. When racing resumed May 15, there were no ontrack spectators. In the final six weeks of the meeting, Santa Anita housed jockeys in on-site accommodations on race nights, the only track to do so in Southern California. Los Alamitos has operated its ongoing evening Quarter Horse and lower-level Thoroughbred meeting without spectators. A two-week daytime Thoroughbred meeting at Los Alamitos earlier this summer was run without spectators. Earlier this month, five jockeys that rode at Los Alamitos on July 4 tested positive for coronavirus. In its statement, Del Mar said that 14 of the 15 jockeys that tested positive this week rode at Los Alamitos earlier this summer.