Dr. Nancy Messonnier is the director of the National Center for Immunization and Respiratory Diseases at the Centers for Disease Control and Prevention (CDC). Her impressive bio lists a number of top positions that she has held in the CDC, and it also notes that she has received multiple awards.

In recent days, Messonnier has taken a leading role in warning the public about the threat that the novel coronavirus strain known as COVID-19 poses to the United States. The Wall Street Journal noted that Messonnier said it was just a question of when coronavirus will circulate in the U.S. The Daily Beast quoted her as saying, “We expect to see more cases of person-to-person spread among close contacts. ... The goal here is to slow entry of this virus into the United States.” CNBC quoted her calling for schools to divide students into smaller groups or to close entirely and conduct courses online. Many other outlets have quoted her as well.

But right-wing media have begun to coalesce around a conspiracy theory that Messonnier’s warning should be disregarded because she is the sister of former Trump appointee Rod Rosenstein. Rosenstein was a frequent target of pro-Trump propagandists for appointing Robert Mueller as a special counsel in the Russia investigation.

From a QAnon Twitter account to Rush Limbaugh's show

The conspiracy theory about Messonnier and Rosenstein goes back at least to a QAnon Twitter account noting their connection in early January.

It really started to pick up speed this week.

On February 25, Rush Limbaugh ranted about Messonnier, suggesting an anti-Trump conspiracy after he learned she’s related to Rosenstein. It was also picked up by a poster on white nationalist message board 8kun. Soon thereafter, it jumped to 4chan's “/pol/,” a slightly less extreme white nationalist message board. The Conservative Treehouse, a right-wing blog featured on Lou Dobbs' Fox Business show before, also posted about the conspiracy theory.

Others followed suit:

On the morning of the February 26, Joe Hoft (the brother of Jim Hoft, proprietor of the Gateway Pundit) posted about it. Hoft wrote that Messonnier’s remarks while President Donald Trump was in India were “a startling rebuke” and that it was “eerily similar to past Presidential trips when former and corrupt DAG Rod Rosenstein and the corrupt and criminal Mueller gang would drop shocking news as the President was overseas.”

Later on the 26th, Rush Limbaugh returned to the conspiracy theory, with the transcript of his show hyperlinking to Hoft’s post. After suggesting that Messonnier was not to be trusted, Limbaugh quickly changed the subject to suggest that the virus may just disappear once the weather warms up. Scientists have cast doubt on that theory as well.

Meanwhile, Trump is reportedly furious at Messonnier: