Danish researchers showed that among 4882 HIV-infected individuals, they observed 336 PJP cases, but for the time period 2016–2021, compared to 1995–1999, PJP risk declined by over 90% after the first year of HIV diagnosis, and by over 40% in the first year, if baseline CD4 T cell count was <200 cells/μL [46]. This evidence concerns the gene CD4 and pneumocystosis.