IL-17A was below the limit of detection in both Mtb-LT1 and Mtb-HT1 infected mice at week 2 post infection, however, at week 3 and 4 post infection IL-17A levels were greater in Mtb-LT1 infected mice compared to Mtb-HT1 infected mice (Fig. 4b). Here, IL17A is linked to infection.