A compendium of 8,176 bat RNA viral metagenomes reveals ecological drivers and circulation dynamics.

Bats are natural hosts for many emerging viruses for which spillover to humans is a major risk, but the diversity and ecology of bat viruses is poorly understood. Here we generated 8,176 RNA viral metagenomes by metatranscriptomic sequencing of organ and swab samples from 4,143 bats representing 40 species across 52 locations in China. The resulting database, the BtCN-Virome, expands bat RNA virus diversity by over 3.4-fold. Some viruses in the BtCN-Virome are traced to mammals, birds, arthropods, mollusks and plants. Diet, infection dynamics and environmental parameters such as humidity and forest coverage shape virus distribution. Compared with those in the wild, bats dwelling in human settlements harboured more diverse viruses that also circulated in humans and domestic animals, including Nipah and Lloviu viruses not previously reported in China. The BtCN-Virome provides important insights into the genetic diversity, ecological drivers and circulation dynamics of bat viruses, highlighting the need for surveillance of bats near human settlements.