SAN JOSE (CBS SF) – More than 90 COVID-19 cases in three counties, including 77 in Santa Clara County, have been linked to a Northern California youth basketball tournament conducted against restrictions to slow the virus, health officials said.

According to the Santa Clara County Public Health Department, the outbreak was linked to teams from a South Bay youth program that traveled to Placer County for a tournament that took place on November 7 and 8. Officials said the tournament took place indoors, with players in close contact.

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Following the tournament, 33 of the 37 players and all three coaches from the Santa Clara County teams tested positive.

As of Friday, the outbreak has infected 39 youth players, three coaches and 35 additional contacts in Santa Clara County, health officials said. An additional 17 cases have been found in other counties so far.

“Public Health orders, directives, and guidance around contact sports and sporting events are in place for a reason. The risk of transmission in these settings can easily result in community spread that threatens the most vulnerable among us,” said Dr. Monika Roy, the county’s assistant public health officer.

Santa Clara County Public Health Officer Dr. Sara Cody, who has placed a three-week ban on all contact sports in the county, said in a statement, “We risk continued, uncontrolled spread of the disease throughout our community and even more loss of life if we don’t each do absolutely everything we can to limit contact with anyone outside of our own household.”

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Health officials also said the youth basketball program failed to timely and properly report the initial positive cases among staff and players. The private basketball program, which includes middle- and high school-aged players, has been cited by county officials.

The California Department of Public Health has initiated an enforcement investigation involving the tournament operator, health officials said.

Santa Clara County health officials have focused on prohibiting contact sports to reduce the risk of spread during the pandemic. Restrictions adopted by the county have led the San Francisco 49ers, the currently undefeated San Jose State Spartans football team and the Stanford football team to leave the area for practices and games.

The 49ers are currently playing the team’s “home” games at State Farm Stadium in Glendale, Arizona.

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All sports activities — youth or otherwise — where participants come within six feet of one another or involve interaction between more than one stable group are completely prohibited under current public health orders in effect in Santa Clara County.