Pfizer partnered with Marvel to release the 'Everyday Heroes' strip yesterday 

Comic's release comes amid sluggish uptake of the booster vaccine in the US 

But Professor David Livermore told MailOnilne it appears to be aimed at children 

Pfizer's Covid vaccine comic was today slammed as 'ethically dubious in the extreme' for trying to appeal to children.

The pharmaceutical giant partnered with Marvel to release the 'Everyday Heroes' strip yesterday, in a push to encourage people to get a booster jab.

It features the Avengers fighting off the villain Ultron, in a symbolic metaphor of Pfizer's push against Covid with the vaccine.