CD4 and infection: A CD4 back calculation model estimated an 80% chance of a decline in incidence between 2019 and 2021 in this population.16 In contrast to our results, Brizzi and colleagues32 estimated a 40% probability of achieving the elimination of HIV transmissions, defined as fewer than one newly acquired infection per 10 000 GBMSM per year, by 2030 (corresponding to fewer than 50 infections among GBMSM).