CD4 and infection: In women who were users of biomass fuels, an increased TH2 response was described with an increase in the Treg cells, CD4+ and CD25+, a subset that can inhibit effector T cell response.[9] In this case, much of the regulatory activity is exerted by IL-10 and TGFβ, perpetuating the TH2 response and leading to chronic inflammation, and less clearance of infection.[7,8] Our data supports this finding, as we noted that infection rates were higher with TF in children who were exposed to a cooking fire, suggesting a prolongation of infection.