A new study from the Swiss Federal Institute of Technology in Zürich is providing some early statistical confirmation of something that doctors have only been able to report anecdotally: Fox News may actually be dragging down the COVID-19 vaccination rates of its own viewers — specifically, among younger viewers who Fox personalities insist don’t need to bother with it.

“Overall, an additional weekly hour of Fox News viewership for the average household accounts for a reduction of 0.35 to 0.76 weekly full vaccinations per 100 people during May and June 2021,” the study concluded, adding that the authors “will continue to update [their] estimates in the next weeks as more data become available.”

The immediate outlook for those next weeks does not look very promising, however, considering how frequently the network undermined vaccination efforts in July. And its coverage just keeps getting worse.

During the period of the Swiss study, Fox prime-time host Tucker Carlson mounted a series of false claims that the COVID-19 vaccines were deadly and suggested that the vaccination effort was implementing a new kind of segregation, calling vaccine requirements the “medical Jim Crow.” Other Fox hosts called the vaccination of children “disgusting,” and warned of an “East German-style ‘show me your papers'” society.

By contrast, viewership of either CNN or MSNBC was not found to have a significant effect on vaccination rates compared to the general population.

This level of granularity in the data may help to explain a running mystery surrounding the network’s coverage: Fox News is not necessarily killing all of its own viewers, as the core older audience is still getting vaccinated just as much as anyone else in that demographic. In perhaps the most famous example, Fox News founder Rupert Murdoch received his vaccination all the way back in December 2020, at age 89. But his son, Fox Corp. CEO Lachlan Murdoch, has publicly supported Carlson’s ongoing misinformation against the vaccines.

Instead, it might only be the younger half of Fox viewers who are actually taking the network’s dangerous advice — something that Fox’s coverage was urging back in April, and continued into the summer.

This becomes especially important because there is evidence that the Delta variant has been hitting younger people than previous waves, in addition to hitting the unvaccinated harder than those who received a full dosage. All told, the country is now on track for another 100,000 more COVID-19 deaths by the end of the year.

We will have to wait, of course, to see whether these effects on vaccination rates have continued since May and June. But based on Fox’s continued coverage, it’s not a rosy picture.