Outbreaks at school campuses are on the rise since Los Angeles County students returned for in-person learning this month, with unvaccinated students and those involved in school sports at higher risk, public health officials said Wednesday.

Three outbreaks a week were reported over the first few weeks of August, but last week the figure increased to eight outbreaks involving 72 students and three staff members, said L.A. County public health Director Barbara Ferrer, who called the early data “sobering.”

“We anticipate that there’ll be an upward trend in outbreaks as more schools reopen,” she said.

A total of 5,207 student cases and 729 staff cases were reported from Aug. 15 to Aug. 29, with a vast majority of the cases at L.A. Unified campuses, which test everyone weekly.

Of the campus outbreaks so far this academic year, 47% were connected to sports teams.

The latest outbreak figures mirror trends from last October and November, when the county was entering the devastating winter surge, Ferrer said.

In all, 849 schools reported one positive case, 193 LAUSD schools and 105 campuses in other districts reported two cases, and 621 LAUSD schools and 94 other school sites reported three or more cases.

Ferrer noted that an instance of three or more cases at one school is only considered an outbreak if the cases are linked to each other.

Among those eligible, unvaccinated children 4 times more likely to get COVID

Case rates have risen among children in all age groups since the beginning of July, and they’re increasing most rapidly among those ages 5 to 11 — school-aged children who are not eligible for a vaccine.

Over the two weeks between Aug. 14 and Aug. 21, the case rate increased 50% in this age group, while the rate increased 13% among children 4 and younger, and 24% among children 12 to 17. Data shows case rates are continuing to increase in those ages 5 to 11 while dropping among other age groups, Ferrer said.

Among kids at least 12 years old, case rates are lowest among those who are vaccinated, while unvaccinated children are four times more likely to get infected, according to the public health director.

There are 57 cases among every 100,000 vaccinated children, compared to 480 cases among every 100,000 teens who are unvaccinated. Hospitalizations, likewise, are eight times higher in unvaccinated children.

But while many other areas nationwide have reported pediatric hospitalizations are higher than at any other point in the pandemic, L.A. County has not seen a similar trend. Pediatric hospitalization rates are higher now than they were in the spring and early summer, but they’re still nowhere near what they were during the winter surge, Ferrer said.

“This pattern may reflect the fact that many adults are vaccinated, and most people are wearing masks when around people outside their household, including children,” she said. “Both of these steps may be playing an important role in protecting our children.”

But Ferrer noted that hospitalizations are a lagging indicator, and “we’re going to need to carefully watch the case rates among children over the upcoming weeks.”

Officials seek to ramp up vaccination to better protect ineligible students

As of Aug. 29, 48% of L.A. County teens 12 to 15 years old were fully vaccinated, and 60% had received at least one dose. Meanwhile, 57% of 16- and 17-year-olds were fully vaccinated, and 68% partially vaccinated.

“The most powerful strategy we have for keeping schools open is getting these numbers within the range of 100%,” Ferrer said.

Meanwhile, officials estimate that 81% of public school district staff members have received at least one dose, said L.A. County Superintendent of Schools Debra Duardo.

Officials are ramping up efforts to increase vaccine access at schools, opening 375 mobile vaccine clinics on campuses. Duardo said more will open over the next two months in communities that have been disproportionately impacted by the pandemic.

Three school districts — L.A. Unified, Culver City Unified and Glendale Unified — are mandating vaccines for staff and routinely testing those with religious or medical exemptions, while another eight districts are considering such a mandate.

So far, only Culver City Unified has implemented a vaccine mandate for eligible students. Duardo had said another two districts — Palmdale and ABC Unified in Cerritos — were considering one, but L.A. County education officials later said those plans were scrapped.

According to Duardo, an additional 13 districts are considering a mandate for students eligible to get a vaccine.

Out of the 80 public school districts countywide, all but two are accepting federal funding to support widespread testing, and 29 of them already have such a program in place, Duardo said.

Meanwhile, 55 individual charter schools and 20 charter management organizations have accepted the testing funding. Combined, that represents a total of 131 individual charter schools implementing testing, and 125 of them already have programs operating.

“In so many ways, the most important task in front of us right now is to do everything we can to keep children, teachers and staff safe at their schools,” Ferrer said. “If we work together to take care of each other, I know we have a better chance of being successful.”