"We have been notified of 41 cases of suspected vaccine failure with the Janssen vaccine, of which 36 were classified as serious," said the regulatory authority to Lusa.

On Monday, the French Medicines Agency (ANSM) indicated that a "significant number" of cases of failure of the Janssen Covid-19 vaccine, which works with a single dose, had been detected in that country.

"A significant number of cases of Janssen vaccine failure have been reported, including severe forms (death, resuscitation) as well as an above-normal presence of patients vaccinated with Janssen in the intensive care of two CHU (University Hospital Centers)," said the ANSM.

In Portugal, according to Infarmed, out of a total of 36 serious situations detected, “five led to hospitalisation and 31 were considered clinically relevant”.

“Considering that in Portugal more than one million doses of this vaccine have already been administered, this would represent an incidence of four reported cases per 100,000 vaccines”, added the national regulator, guaranteeing that this number of notifications “is far below the expected value, taking into account the results obtained in the clinical trials used for the approval of this vaccine”.

In France, among people vaccinated with the Janssen vaccine, 32 cases of infection with covid-19 were reported, corresponding to an incidence of 3.78 cases per 100,000 people.

Of these 32 cases, 29 were serious and there were four deaths (of people aged between 73 and 87 years).

In March of this year, the European Medicines Agency (EMA) granted conditional authorisation for the vaccine from Janssen, a pharmaceutical company of the Johnson & Johnson group - one of the four that is part of the Portuguese vaccination plan - for people to from 18 years old.