Table 2.

Transmission rate model parameter values

Model parameter	Parameter value
HIV incidence (2008), I	47,800 [23]
Persons living with HIV in the US (2008), N = N0 + N1 + N2 + N3	1,178,350 [25]
Acutely-infected persons on any given day, N0	6417 a
Non-acutely infected PLWH who are unaware of their status, N1	229,983 b
Serostatus-aware PLWH who are not receiving ART, N2	515,360 [15]
Serostatus-aware PLWH who are receiving ART, N3	426,590 [15]
Ratio of transmission rates for N0 and N1, μ(0,1) = γ1/γ0	0.1235 [26]
Ratio of transmission rates for N1 and N2, μ(1,2) = γ2/γ1	0.43 [10,17]
Ratio of transmission rates for N2 and N3, μ(2,3) = γ3/γ2	0.23 c

^aCalculated from annual incidence using method described in [10].

^bObtained by subtracting acutely-infected persons from total number of PLWH who are unaware of their infection, 236,400.[25]

^cCalculated as 1 - 0.77, based on estimate that 77% of PLWH on ART have suppressed viral load (≤ 200 copies/mL).[15]