Anti-vaccine activists have placed leaflets in a hospital car park.
The leaflets, put on cars outside the Royal Berkshire Hospital in Reading, were designed to look as if they were made by Public Health England but are fake.
They contained incorrect and inaccurate information about the COVID-19 vaccine.
The action has been criticised by hospital bosses.
Today, the Chief Executive of the Royal Berkshire NHS Foundation Trust, Steve McManus, tweeted: "It is worth noting that our amazing staff at Royal Berkshire NHS Foundation Trust have cared for over 2,300 patients with Covid to date.
"Whatever views might be held about the Covid vaccine, this is no way to show respect for the incredible staff and volunteers at Royal Berkshire NHS Foundation Trust and across the NHS who have put themselves out there for patients and our community day after day over the last 18 months."
The trust also added that the leaflets had been removed and advised all visitors to the hospital to ignore the contents of them.