The transatlantic slave trade led to the emergence of new pathogenic viruses: they moved from Africa to North America.
The authors of the new work found that European colonists brought new viruses to North America, including smallpox, measles and mumps: they caused outbreaks of disease that led to a significant decrease in the population in Native American communities.
Numerous outbreaks of disease in what is now Mexico killed millions of indigenous people in the 16th century. But the specific pathogens responsible for these events are currently unknown.
In order to find out which viruses have spread due to the transatlantic slave trade, the authors of the work extracted ancient viral DNA from the teeth of the likely victims of these outbreaks: they were buried in a hospital and a chapel of the colonial era.
The victims were indigenous peoples as well as African Americans from Africa. The team then used this DNA to reconstruct viral genomes. As a result, they identified the ancient hepatitis B virus and parvovirus B19. The authors compared the genomes and concluded that both viruses originated from Africa.
The results of the work confirmed that during the epidemics, several new viruses circulated at once, which is why they turned out to be so deadly for indigenous communities.