Immunocompetence of honey bee larvae as affected by DWV infection. (A) Nylon threads at 24 h after implantation into the body of fifth instar honey bee larvae with increasing DWV infection levels. (B) Level of melanization of a nylon thread implant in honey bee larvae with different levels of viral infection, measured as number of DWV genome copies (ρ = −0.656, n = 28, P < 0.001). (C) Level of encapsulation of a nylon thread implant in honey bee larvae with different levels of viral infection, measured as number of DWV genome copies (ρ = −0.390, n = 28, P = 0.040).