Ancient viral genomes reveal introduction of HBV and B19V into Mexico during the transatlantic slave trade

After the European colonization of the Americas there was a dramatic
population collapse of the Indigenous inhabitants caused in part by the
introduction of new pathogens. Although there is much speculation on the
etiology of the Colonial epidemics, direct evidence for the presence of
specific viruses during the Colonial era is lacking. To uncover the
diversity of viral pathogens during this period, we designed an enrichment
assay targeting ancient DNA (aDNA) from viruses of clinical importance and
applied it on DNA extracts from individuals found in a Colonial hospital
and a Colonial chapel (16th c. – 18th c.) where records suggest victims of
epidemics were buried during important outbreaks in Mexico City. This
allowed us to reconstruct three ancient human parvovirus B19 genomes, and
one ancient human hepatitis B virus genome from distinct individuals. The
viral genomes are similar to African strains, consistent with the inferred
morphological and genetic African ancestry of the hosts as well as with
the isotopic analysis of the human remains, suggesting an origin on the
African continent. This study provides direct molecular evidence of
ancient viruses being transported to the Americas during the transatlantic
slave trade and their subsequent introduction to New Spain. Altogether,
our observations enrich the discussion about the etiology of infectious
diseases during the Colonial period in Mexico.