At 4 wks post-infection, despite enhanced numbers of lymphocytes (Figure S3) and increased levels of parasite antigen (Figure 2A) at the site of infected sand fly bite versus needle inoculation in ALM+CpG vaccinated mice, we observed a decrease in the frequency of both IFN-γ+ (6.8% versus 11%) and TNF-α+ (3.7% versus 9.3%) L.m.-specific T cells (Figure 2, C and D), as well as reduced levels of secreted IFN-γ (Figure 2E). The gene discussed is TNF; the disease is infection.