The Swissmedic regulatory authority and regional authorities in the central canton of Lucerne confirmed reports that a 91-year-old person who was among the first to receive the vaccine in Switzerland last week had died.

But a Swissmedic spokesman insisted to AFP that the timing of the death on Tuesday in a Lucerne nursing home, just five days after receiving the vaccine, “was a coincidence”.

“Investigations by the cantonal health authorities and by Swissmedic have shown that, based on the medical history and disease development, a connection between the death and the Covid-19 vaccination is highly unlikely,” Swissmedic said in a statement.

The deceased had already been suffering from several diseases, the agency pointed out.

“Neither the medical history nor the acute course of disease suggest a direct causal link between the Covid-19 vaccine and the death,” it said.

“Pre-existing diseases” had been listed as the natural cause of death on the death certificate, it pointed out.

Swissmedic, which approved the Pfizer-BioNTech vaccine on December 20, stressed that no unknown side effects had occurred since vaccinations had begun in the country a week ago.

Millions of people have already received the vaccine across a number of countries, and no deaths have been connected to the jabs so far.

Pfizer and BioNTech said they were aware of the death, and said their “thoughts are with the bereaved family.”

The two companies also stressed in a statement that “serious adverse events, including deaths that are unrelated to the vaccine, are unfortunately likely to occur at a similar rate as they would in the general population of elderly and at-risk individuals who are currently being prioritised for vaccination.”