Public Health England’s Twitter feed doesn’t typically give its 150,000 followers reasons to be filled with abject terror.

Recent tweets encouraged Brits to take “steps to cut excess calorie consumption” and prompted people over 70 to get a shingles vaccine. The health agency recently waged a Twitter offensive to debunk rumors that it was banning cake.

But Sunday’s message was a bit more dire, even if it appeared that someone at the agency went through pains to stave off a potential public panic.

The agency warned that anyone who had dined at a certain restaurant or pub in the city of Salisbury may have been exposed to a tiny amount of a potentially deadly nerve agent used in what authorities have deemed an assassination attempt.

A week ago, Sergei Skripal and his daughter, Yulia, were found unconscious on a public bench in Salisbury.

He is a 66-year-old former colonel in Russia’s military intelligence service who was convicted of helping British agents, then freed in a spy swap. She is a 33-year-old who had just dined with her father at a restaurant named Zizzi.

Police said the father and daughter were “targeted specifically” with a nerve agent.

Officials have not publicly identified the nerve agent, but they have found traces of it at the restaurant, according to the Associated Press.

A police investigator who was at the scene also was sickened by the nerve agent.

Now, the government is telling anyone who had dined at Zizzi or the Mill Pub nearby during a 33-hour window that there is a chance — a tiny one — that they carried the nerve agent home on clothing or shoes. If so, a person could be sickened by repeated exposure.

That is, of course, the bad news. The good news, Public Health England said over and over again, is that the “health risk is low,” “there’s a small risk to health” and that the leaflet warning people is “precautionary.”

“While there is no immediate health risk to anyone who may have been in either of these locations, it is possible, but unlikely, that any of the substance which has come into contact with clothing or belongings could still be present in minute amounts and therefore contaminate your skin,” the statement from Public Health England said. “Over time, repeated skin contact with contaminated items may pose a small risk to health.”

The agency said anyone who was at one of the dining establishments last Sunday or Monday could (and should) take simple actions to prevent themselves from getting sick: Wash clothes in a washing machine, wipe personal items down with baby wipes and then trash the wipes, or hand-wash glasses and jewelry with warm water and detergent.

“It’s really important to understand the general public should not be concerned,” Jenny Harries of Public Health England said at a news conference after the release of the leaflet, according to the AP. “There is, on the evidence currently, a very low risk.”

She spoke during a week in which investigators in hazmat suits had been going in and out of a tented restaurant and pub, in part searching for clues that could lead them to whoever wanted Skripal dead.

According to the AP, politicians and law enforcement officials say they believe the attack fits a pattern of suspicious deaths in the United Kingdom and in the United States that could link back to Russia. Past dead and injured include an ex-spy poisoned by radioactive tea and a former aide to Russian President Vladimir Putin who died of blunt-force trauma inside a Washington hotel room.

“Russian leaders seem to go out of their way to get rid of anybody that seems to be in their way, someone who’s betrayed them, someone who’s interrupting the money flow, and they don’t seem to care about borders. They just go wherever they have to go to get their guy,” said Joseph D. Serio, the American author of “Investigating the Russian Mafia,” told the AP.

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