GFM1 and infection: The strain lacking a functional allele of EFG1 (4), 94015, was the least virulent, with only 40% moribundity 4 weeks post-infection (Fig. 2E; median survival time: undefinable); 78042 also showed low virulence with 80% moribundity at 4 weeks, which did not increase further over an additional 3 weeks (Fig. 2F).