A sex-role-preference model for HIV transmission among men who have sex with men in China

Table 1 Parameters.

Para	Description	Value	Source
r _T	source rate of Only-Top MSM	96667	estimate
r _V	source rate of Versatile MSM	603950	estimate
r _B	source rate of Only-Bottom MSM	70817	estimate
d _M	death rate of susceptible MSM	0.022	estimate
d _I	death rate of infected MSM	0.105	estimate
n _T	number of AI sex partners per year of Only-Top MSM	11.5	[16]
n _V	number of AI sex partners per year of Versatile MSM	12.4	[16]
n _B	number of AI sex partner per year of Only-Bottom MSM	13.6	[16]
c _T	number of AI acts with each sex partners per year of Only-Top MSM	4.4	[16]
c _V	number of AI acts with each sex partners per year of Versatile MSM	4.5	[16]
c _B	number of AI acts with each sex partners per year of Only-Bottom MSM	4.2	[16]
h _TB	transmissibility of HIV from Top to Bottom	0.01	[9, 20]
h _VB	transmissibility of HIV from Versatile to Bottom	0.01	[9, 20]
h _TV	transmissibility of HIV from Top to Versatile	0.01	[9, 20]
h _BT	transmissibility of HIV from Bottom to Top	0.005	[9, 20]
h _VT	transmissibility of HIV from Versatile to Top	0.005	[9, 20]
h _BV	transmissibility of HIV from Bottom to Versatile	0.005	[9, 20]
h _VV	transmissibility of HIV from Versatile to Versatile	0.0075	estimate
伪_y	proportion of infected MSM who know they are infected	0.15	[16]
畏 ^c	condom efficacy	0.9	[16]
蚁 ^c	rate of condom use	0.3	[16]
蠄 ^s	proportion with STI	0.158	[16]
渭 ^s	multiplication factor of STI for HIV	2.89	[21]
谓 _y	proportion of infected MSM who begin to control their behaviour	0.5	[16]

Note 1: The mean values and standard errors of parameters n_T, n_V, n_B, c_T, c_Vand c_Bare
respectively.
Note 2: We estimate that the average life span of HIV infected individual is 9.5 years, so d_I= 0.105. Also, we suppose young MSM begin homosexual sex behavior at 20 years and quit at 65 years, so d_M= 0.022.

ISSN: 1471-2458