A global network of scientists has been sharing genomic sequences of the coronavirus with one another in near real time since the start of the pandemic. This has been crucial to tracking the spread of the virus and the emergence of variants. The most popular database where scientists exchange this information, open-source, is called Gisaid. This month, it collected its 4 millionth sequence. The significance is not lost on scientists. As The World’s Elana Gordon reports, it came from a new effort in Republic of Congo.