“‘It’s a very special picture.’ Why vaccine safety experts put the brakes on AstraZeneca’s COVID-19 vaccine”
“The decision this week by more than 20 European countries to temporarily stop using AstraZeneca’s COVID-19 vaccine has opened a rift between vaccine safety experts, who say the cases of serious clotting and bleeding that triggered the pause are alarming and unusual, and public health officials concerned that the immunization pause on a continent in the grip of the pandemic’s third wave could take a heavy toll.”
Age-dependent immune response to the Biontech/Pfizer BNT162b2 COVID-19 vaccination
https://www.medrxiv.org/content/10.1101/2021.03.03.21251066v1
“While the majority of participants in both groups produced specific IgG antibody titers against SARS-CoV-2 spike protein, titers were significantly lower in elderly participants. Although the increment of antibody levels after the second immunization was higher in elderly participants, the absolute mean titer of this group remained lower than the <60 group. After the second vaccination, 31.3 % of the elderly had no detectable neutralizing antibodies in contrast to the younger group, in which only 2.2% had no detectable neutralizing antibodies.”