A new study in PLoS Pathogen has found that mosquitoes benefit from bacteria-laden food. The bacteria stimulate their immune system and protect them against the malaria parasite. From the abstract:
Malaria-transmitting mosquitoes are continuously exposed to microbes . . . Global transcription profiling of septic and [microbe-free] aseptic mosquitoes [made aseptic with antibiotics] identified a significant subset of immune genes that were mostly up-regulated by the mosquito’s microbial flora . . . Microbe-free aseptic mosquitoes displayed an increased susceptibility to Plasmodium infection while co-feeding mosquitoes with bacteria and P. falciparum gametocytes resulted in lower than normal infection levels. Infection analyses suggest the bacteria-mediated anti-Plasmodium effect is mediated by the mosquitoes’ antimicrobial immune responses, plausibly through activation of basal immunity.
Another view of this study is that it is more evidence of the dangers of antibiotics: They weakened the immune system. As you may know, and as I was told recently by a pediatrician, doctors “hand out antibiotics like candy.”
Thanks to Janet Rosenbaum.