Can microbes fly? Experimental viral and bacterial aerosolization

Bacterial and viral aerosolization influences atmospheric processes and the spread of harmful microbes. Sea spray aerosol (SSA) contributes to microbial aerosolization through bubble bursting in the sea surface microlayer (SML). However, taxa with the ability to become airborne as well as their environmental influence factors have not accurately been identified so far.

Michaud et al. (2018) addressed this gap by using a custom ocean-atmosphere facility simulating a natural ecosystem. They assessed viral and bacterial abundance and community structures in subsurface water, SML and SSA using metagenomic approaches during an induced phytoplankton bloom. They identified several bacterial taxa with high aerosolization ability and a conservation of this ability within taxonomic orders and classes. In contrast, viruses were less able to aerosolize and highly influenced by changing environmental factors. In both, bacteria and viruses, they also found several mechanisms promoting aerosolization, many of which involved increased hydrophobicity. Even though the experimental setup is still limited due to the absence of several abiotic and biotic factors, like diurnal light conditions and predation, and sampling difficulties in the SSA, it is still unprecedented in its accuracy of the simulation of this unique ecosystem and forms a baseline that future studies can build on.

Michaud, J. M., Thompson, L. R., Kaul, D., Espinoza, J. L., Alexander Richter, R., Xu, Z. Z., … Prather, K. A. (2018). Taxon-specific aerosolization of bacteria and viruses in an experimental ocean-atmosphere mesocosm. Nature Communications, Vol. 9. https://doi.org/10.1038/s41467-018-04409-z