I'm facing the same problem & I've heard people talking about certain blood group being more attractive to the mosquitoes;but has this been proven?
The article doesn't mention blood group & specifically mentions that the merit of the research in finding the path i.e. CO2, Odour.
I dont' understand how blood can form path, unless it applies to only second bite i.e. Mosquitoes prefereing individuls with certain blood group after tasting it once.