COVID-19 rates in the Southwestern United States reached 12.5% — the highest in the nation — according to new data from the U.S. Centers for Disease Control and Prevention released this week. Meanwhile, Los Angeles County recorded the highest COVID-19 levels in its wastewater since February.

Combined, California Nevada and Arizona clocked in at 12.5%

The spike, thanks to the new highly contagious “Stratus” variant, comes as students across California return to the classroom, now without a CDC recommendation that they receive updated COVID-19 shots. That change in policy, pushed by Health and Human Services Secretary Robert F. Kennedy Jr., has been criticized by many public health experts.

The COVID-19 virus, SARS-CoV-2, mutates often, learning to better transmit itself from person to person and evade immunity created by vaccinations and previous infections.

The Stratus variant, first detected in Asia in January, reached the U.S. in March and became the predominant strain by the end of June. It now accounts for two-thirds of virus variants detected in wastewater in the U.S., according to the CDC.

The nationwide COVID-19 positivity rate hit 9% in early August, surpassing the January post-holiday surge, but still below last August’s spike to 18%. Weekly deaths, a metric that lags positivity rates, has so far remained low.

Levels of the COVID-19 virus in wastewater can catch trends earlier than clinical tests and better account for asymptomatic cases.

In May, RFK Jr. announced the CDC had removed the COVID-19 vaccine from its recommended immunization schedule for healthy children and healthy pregnant women.

The secretary argued it was the right move to reverse the Biden administration’s policy, which in 2024, “urged healthy children to get yet another COVID shot, despite the lack of any clinical data to support the repeat booster strategy in children.”

That statement promptly spurred a lawsuit from a group of leading medical organizations — including the American Academy of Pediatrics, the American College of Physicians and the American Public Health Association — which argued the “baseless and uninformed” decision violated federal law by failing to ground the policy on the recommendation of the scientific committee that looks at immunization practices in the U.S.

The Advisory Committee on Immunization Practices has been routinely recommending updated COVID-19 vaccinations alongside the typical yearly flu vaccination schedule. In its update for the fall 2024-spring 2025 season, it noted that in the previous year, a COVID-19 booster decreased the risk of hospitalization by 44% and death by 23%.

The panel argued the benefit outweighed isolated cases of heart conditions and allergic reactions associated with the vaccine.

The panel also acknowledged that booster effectiveness decreases as new COVID-19 strains — for which the boosters were not designed — emerge. Nevertheless, it still felt that most Americans should get booster shots.

The CDC estimates that only about 23% of adults and 13% of children received the 2024-2025 COVID-19 booster — even with the vaccine recommendation still in place. That’s compared to roughly half of adults and children who received the updated flu shot in the same time frame.

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