Most of the U.S. is leaving mask policies up to school districts

With about a month until back to school begins in many K-12 districts, most states in the U.S. have no uniform plan to require masks, even as public health guidance still strongly recommends them for the unvaccinated.

Why it matters: Kids younger than 12 still haven't been eligible for vaccination and, without mitigation efforts like masking, the fall could bring an uptick in the spread of COVID.

• That's particularly of concern for epidemiologists with the growth in cases from the Delta variant.
• Several reports of COVID cases stemmed from summer camps, a precursor of what could be in store this fall.

Driving the news: The CDC released new recommendations Friday urging K-12 schools to fully reopen in the fall, even if some mitigation steps previously laid out are not feasible, such as social distancing.

• With the FDA's expanded eligibility of the Pfizer vaccine to 12-to-15-year-olds, schools may allow those who received the shot to be exempt from masks, the CDC said.

About half of the states don't plan to enforce mask policies in schools, according to a mask policy tracker by Burbio.

• Within the past two weeks, eight states have rolled back their mask mandates for schools and left local districts to decide, while another eight states have banned districts from enforcing masks altogether.

Ten states, including California, will mandate students wear masks. That will hold true, regardless of vaccination status among 12-to-18-year-olds, the state's health department said Friday.

• "At the outset of the new year, students should be able to walk into school without worrying about whether they will feel different or singled out for being vaccinated or unvaccinated — treating all kids the same will support a calm and supportive school environment," California Health and Human Services agency secretary Mark Ghaly said in a statement.

What to watch: Experts are still unsure how back to school will go in the U.S.

But a recent study in the British Medical Journal suggests the Delta variant is driving outbreaks in primary schools in the U.K. At least 375,000 students were absent due to Delta cases at the end of June, which jumped to 640,000 last week.