"Given the suspension of a batch of Janssen brand vaccines (…) and the consequent reduction in the availability of vaccines, it was decided to immediately suspend the 'open house' modality", states a note from the Vaccination Task Force.

The Vaccination Plan Task Force stresses that the “open house” modality, in which people could be vaccinated without appointment, will be resumed “as soon as possible”.

The “open house” method was available for vaccinating people aged 40 years plus and who had not been infected with Covid-19 in the past six months.

According to the Task Force, the 'open house' ensures that all eligible people are able to access the vaccine process.

On Wednesday, the National Authority for Medicines and Health Products (Infarmed) announced the suspension of a batch of Janssen vaccines after users passed out after taking the vaccine at the Covid-19 Vaccination Center in Mafra.

In a statement, the national authority of the medicine explained that the measures come “following the cases of adverse reactions (syncope), notified with the Janssen vaccine, in this vaccination center.

Due to this situation, the medicine authority decided to start “a process of investigation of the quality of the remaining units of the vaccine at that vaccination site, as well as suspend this batch until the necessary investigations are concluded”.

The latest official figures indicate that more than 42 percent of Portuguese people have completed vaccination and 60 percent have already taken at least one dose.

This week alone, more than one million doses have been administered, the highest since the start of the Covid-19 vaccination campaign.