Group A Strep and Necrotizing Fasciitis

[shan putnam]

Does anyone have a good explantion of how Group A strep can cause
invasive disease; either localized cellulitis and/or necrotizing
fasciitis/  

Our lab isolated GAS from a patient with NF and isolated the same
(DNA fingerprinted) exact strain from an asymptomatic roommate. 

I have started to dig on info pertaining to this, but it seems
pretty sketchy.   Is there an immune status difference?

Thanks for the info


Shan