Transcriptional Response of Honey Bee Larvae Infected with the Bacterial Pathogen Paenibacillus larvae
American foulbrood disease of honey bees is caused by the bacterium Paenibacillus larvae. Infection occurs per os in larvae and systemic infection requires a breaching of the host peritrophic matrix and midgut epithelium. Genetic variation exists for both bacterial virulence and host resistance, and a general immunity is achieved by larvae as they age. American foulbrood (AFB) is a bacterial infection of honey bee (Apis mellifera) larvae that is highly contagious and virulent [1]. The causative agent is Paenibacillus larvae, a gram-positive bacterium that establishes an initial infection in the midgut lumen after larvae consume spore-contaminated food. Systemic infection is achieved when vegetative cells breach the peritrophic membrane, a physical barrier to infection that is secreted by the anterior midgut, and then penetrate between epidermal cells [2]. Honey bee larvae are only vulnerable to P. larvae by oral inoculation, and this susceptibility attenuates by approximately three days after hatching [1].
http://www.plosone.org/article/info%...l.pone.0065424