A COVID summer wave has spread across most of the US and Western states are seeing particularly high numbers of infections.

With more people traveling for the summer and gathering in large groups, public health officials are concerned,

these numbers won't be going down anytime soon.

William Bringham has the latest.

That's right, across 45 states and territories,

COVID infections are rising.

According to the latest data from the CDC, more than half of those regions are showing

high or very high levels of COVID in wastewater samples.

This rise is partly due to a number of new variants

with particular mutations that make it easier

for the virus to spread.

For more on what we can expect for the rest of this summer,

we are joined again by epidemiologist Caitlin Jettelina.

She's the author of the invaluable Substat column

called Your Local Epidemiologist. Caitlin Jettlina. sub-stack column called your local epidemiologist.

Caitlin Jettelina, so nice to have you back on the program.

Help us explain this uptick.

Is it, as I mentioned, new variants? Is it our summer behaviors?

What's driving this?

Yeah, so there's really a combination of three things that drive our summer waves.

One is behavior change.

It's really hot outside.

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