Nationwide biogeography and health implications of bacterial communities in household drinking water

Drinking water at the point of use harbors microorganisms that may pose potential risks to human health. However, the microbial diversity and health impacts of household drinking water are poorly understood, since culture-based methods only target on specific microorganisms and low biomass of drinking water hinders a high-throughput profiling. Here, we used an optimized workflow to efficiently collect microorganisms from low-biomass drinking water and performed deep sequencing of 16S rRNA genes to profile the bacterial diversity and biogeography of 110 household drinking water samples covering 38 cities of 29 provinces/regions in China, and further explored environmental drivers and potential health implications. Our analyses revealed a diverse drinking water community comprising a total of 22,771 operational taxonomic units (OTUs). The spatial turnover of drinking water communities is scale-dependent and appears to be driven largely by rainfall and water source river. The identified potential pathogenic species may have the possibility of causing health risks. Our novel insights enhance the current understanding of the diversity and biogeography of drinking water bacterial communities within a theoretical ecological framework and have further important implications for safe drinking water management and public health protection.