Chile on Tuesday began a new COVID-19 vaccination plan, which calls for the use of Pfizer to men under 45 who have taken the first dose of AstraZeneca‘s vaccine, reported O Estado de São Paulo.

The mix is due to the record of a 31-year-old man that had developed thrombosis with thrombocytopenia syndrome (TTS) seven days after his first AstraZeneca vaccine shot.

After that case, Chile’s government then raised the minimum age of men eligible to receive the AstraZeneca‘s vaccine to 45 years.

Experts believe mixed dosing of vaccines could be a good idea to prevent blood cots. Germany, France, Spain, and Norway are some countries that adopted the mixed vaccination.

Recently, BBC reported that german Chancellor Angela Merkel has received a dose of Moderna as her second shot after having had AstraZeneca as her first.