Feeding on a Infected Host Triggers Temporary Changes in the Microbiome.

The effect of on the microbiome of its vector, (the cat flea) is largely unknown, as the majority of microbiome studies have utilized wild-caught pooled fleas. We surveyed the microbiome of laboratory-origin fed on -infected cats for 24 h or 9 days to identify changes to microbiome diversity and microbe prevalence compared to unfed fleas, and fleas fed on uninfected cats. Utilizing Next Generation Sequencing (NGS) on the Illumina platform, we documented an increase in microbial diversity in fed on -infected cats for 24 h. These changes returned to baseline (unfed fleas or fleas fed on uninfected cats) after 9 days on the host. Increased diversity in the microbiome when fed on -infected cats may be related to the mammalian, flea, or endosymbiont response. Poor acquisition was documented with only one of four infected flea pools having detected by NGS. We hypothesize this is due to the use of adult fleas, flea genetic variation, or lack of co-feeding with -infected fleas. Future studies are necessary to fully characterize the effect of endosymbionts and diversity on acquisition.