The first human in space, Yuri Gagarin, orbited the Earth once on April 12 1961. The most recent successful manned launch delivered Sergey Prokopyev, Alexander Gerst, and Serena M. Auñón-Chancellor to the ISS as crew. Of the three only Gerst had already flown in space before, rendering Auñón-Chancellor and Prokopyev the most recent astronaut/cosmonaut as of 8 June 2018. Before their return they’re expected to orbit the Earth almost 3000 times.
In the 57 years between Gagarin and Prokopyev/Auñón-Chancellor more than 550 people have flown to space. Cosmonauts, astronauts, taikonauts, even space tourists.
When will the 1,000th person reach space?
For the purposes of this question we will only count people who have reached orbit. Sub-orbital flights are explicitly excluded.