Background
Methods
Study setting
Study design
2010 (N = 49) | 2011 (N = 110) | 2012 (N = 166) | 2013 (N = 343) | 2014 (N = 358) | Overall (N = 1026) | ||
---|---|---|---|---|---|---|---|
HIV (%) | VFSW-Unweighted | 8.16 | 5.45 | 3.61 | 3.21 | 1.68 | 3.22 |
VFSW-Weighted1
| 5.65 | 2.95 | 4.26 | 3.23 | 1.53 | 2.84 | |
All-FSW | 1.60 | 1.07 | 1.11 | 0.88 | 0.65 | 1.00 | |
Syphilis (%) | VFSW-Unweighted | 8.16 | 9.09 | 9.64 | 7.87 | 3.91 | 6.92 |
VFSW-Weighted1
| 3.45 | 6.55 | 7.13 | 7.99 | 3.59 | 5.92 | |
All-FSW | 6.10 | 7.24 | 7.14 | 6.28 | 4.68 | 6.22 | |
HCV (%) | VFSW-Unweighted | 0.00 | 2.73 | 2.41 | 3.50 | 2.23 | 2.63 |
VFSW-Weighted1
| 0.00 | 1.47 | 2.51 | 2.33 | 2.57 | 1.67 | |
All-FSW | 1.00 | 0.96 | 1.09 | 0.95 | 0.73 | 0.93 |
Analytical procedure
Results
Prevalence, demographic and behavioral characteristics
2010 (N = 49) | 2011 (N = 110) | 2012(N = 166) | 2013 (N = 343) | 2014 (N = 358) | Overall (N = 1026) | p-value | p-trend | ||
---|---|---|---|---|---|---|---|---|---|
% (n) | % (n) | % (n) | % (n) | % (n) | % (n) | ||||
Age |
>25
| 59.18 (29) | 48.18 (53) | 51.20 (85) | 53.64 (184) | 58.10 (208) | 54.48 (559) | 0.2970 | 0.1700 |
<=25 yrs
| 40.82 (20) | 51.82 (57) | 48.80*81) | 46.36 (159) | 41.90 (150) | 45.52 (467) | |||
Marital status |
Not married
| 57.14 (28) | 52.73 (58) | 56.02 (93) | 51.90 (178) | 43.85 (157) | 50.1 (514) | 0.0470 | 0.0100 |
Married
| 42.86 (21) | 47.27 (52) | 43.98 (73) | 48.10 (165) | 56.15 (201) | 49.9 (512) | |||
Length of working |
<6 m
| 18.37 (9) | 64.55 (71) | 39.63 (65) | 56.85 (195) | 48.60 (174) | 50.2 (514) | 0.0000 | 0.1560 |
> = 6 m
| 81.63 (40) | 35.45 (39) | 60.37 (99) | 42.15 (148) | 51.40 (184) | 49.80 (510) | |||
Education |
<MS
| 61.22 (30) | 56.36 (62) | 54.88 (90) | 41.69 (143) | 53.91 (13) | 50.59 (518) | 0.0002 | 0.2150 |
> = MS
| 38.78 (19) | 43.64 (48) | 45.12 (74) | 58.31 (200) | 46.09 (165) | 49.41 (506) | |||
Community service |
Yes
| 95.92 (47) | 73.47 (72) | 90.96 (151) | 93.0 (319) | 86.87 (311) | 88.76 (900) | 0.0000 | 0.4490 |
No
| 4.08 (2) | 26.53 (26) | 9.04 (15) | 7.00 (24) | 13.13 (47) | 11.24 (114) | |||
Condom use in the last sex |
No
| 16.67 (8) | 15.74 (17) | 13.25 (22) | 7.89 (27) | 3.08 (11) | 8.33 (85) | 0.0000 | 0.0000 |
Yes
| 83.33 (40) | 84.26 (91) | 86.75 (144) | 92.11 (315) | 96.92 (346) | 91.67 (936) | |||
Condom use in the last month |
Inconsistent
| 44.9 (22) | 39.81 (43) | 32.73 (54) | 21.83 (74) | 17.6 (63) | 25.12 (256) | 0.0000 | 0.0000 |
Consistent
| 55.1 (27) | 60.19 (65) | 67.27 (111) | 78.17 (265) | 82.40 (295) | 74.88 (763) | |||
Drug use |
No
| 95.92 (47) | 99.08 (108) | 96.39 (160) | 96.79 (332) | 96.65 (346) | 96.88 (993) | 0.7170 | 0.6120 |
Yes
| 4.08 (2) | 0.92 (1) | 3.61 (6) | 3.21 (11) | 3.35 (12) | 3.12 (32) | |||
HIV knowledge |
<=5
| 59.18 (29) | 34.55 (38) | 62.65 (104) | 54.81 (188) | 60.34 (216) | 56.04 (575) | 0.0000 | 0.0110 |
>5
| 40.82 (20) | 65.45 (72) | 37.35 (62) | 45.19 (155) | 39.66 (142) | 43.96 (451) | |||
Types of venues |
Low-paying
| 83.67 (41) | 72.48 (79) | 73.49 (122) | 50.00 (161) | 48.74 (174) | 57.33 (577) | 0.0000 | 0.0000 |
Medium-paying
| 6.12 (3) | 17.43 (19) | 19.28 (32) | 43.48 (140) | 50.70 (181) | 37.39 (375) | |||
High-paying
| 10.20 (5) | 10.09 (11) | 7.23 (12) | 6.52 (21) | 0.56 (2) | 5.08 (51) | |||
Prevalence (%,95 % CI) |
HIV
| 8.20 % (0.52 %,15.88 %) | 5.50 % (1.24 %,9.76 %) | 3.60 % (1.34 %,5.06 %) | 3.20 % (1.34 %,5.06 %) | 1.70 % (0.36 %,3.04 %) | 3.22 % (2.12 %,4.28 %) | 0.0770 | 0.0050 |
Syphilis
| 8.20 % (0.52 %,15.88 %) | 9.10 % (3.73,14.47 %) | 9.60 % (5.12 %,14.08 %) | 7.90 % (5.05 %,10.75 %) | 3.90 % (1.89 %,5.91 %) | 6.92 % 95.35 %,8.45 %) | 0.0800 | 0.0210 | |
HCV
| 0.00 % (0.00 %,0.00 %) | 2.70 % (−0.33 %,5.73 %) | 2.40 % (0.07 %,4.73 %) | 3.50 % (1.56 %,5.44 %) | 2.20 % (0.68 %,3.72 %) | 2.63 % (1.63 %,.57 %) | 0.6290 | 0.6660 |
Prevalence of infections in relation to demographic and behavioral factors
2010 | 2011 | 2012 | 2013 | 2014 | Overall | p-value | p-trend | ||
---|---|---|---|---|---|---|---|---|---|
% (n/N) | % (n/N) | % (n/N) | % (n/N) | % (n/N) | % (n/N) | ||||
Age |
>25
| 6.9 (2/29) | 5.66 (3/53) | 3.53 (3/85) | 4.35 (8/184) | 2.40 (5/208) | 3.76 (21/559) | 0.633 | 0.154 |
<=25 yr
| 10.0 (2/20) | 5.26 (3/57) | 3.70 (3/81) | 1.89 (3/189) | 0.67 (1/150) | 2.57 (12/467) | 0.063 | 0.005 | |
Marital status |
Not married
| 7.14 (2/28) | 1.72 (1/58) | 3.23 (3/93) | 2.81 (5/178) | 1.91 (3/157) | 2.72 (14/514) | 0.597 | 0.309 |
Married
| 9.52 (2/21) | 9.62 (5/52) | 4.11 (3/73) | 3.64 (6/165) | 1.49 (3/201) | 3.71 (19/512) | 0.043 | 0.004 | |
Length of working |
<6 m
| 0 (0/9) | 4.23 (3/71) | 1.54 (1/65) | 1.03 (2/195) | 1.15 (2/174) | 1.56 (8/514) | 0.407 | 0.191 |
> = 6 m
| 10.00 (4/40) | 7.69 (3/39) | 5.05 (5/99) | 6.08 (9/148) | 2.17 (4/184) | 4.90 (25/510) | 0.18 | 0.027 | |
Education |
<MS
| 13.33 (4/30) | 6.45 (4/62) | 3.33 (3/90) | 5.59 (8/143) | 2.59 (5/193) | 4.63 (24/518) | 0.089 | 0.024 |
> = MS
| 0 (0/19) | 4.17 (2/28) | 4.05 (3/74) | 1.50 (3/200) | 0.61 (1/165) | 1.78 (9/506) | 0.24 | 0.119 | |
Community service |
Yes
| 8.51 (4/47) | 5.56 (4/72) | 3.97 (6/151) | 3.13 (10/319) | 1.93 (6/311) | 3.33 (30/900) | 0.128 | 0.006 |
No
| 0 (0/2) | 7.69 (2/26) | 0 (0/15) | 4.17 (1/24) | 0 (0/47) | 2.63 (3/114) | 0.337 | 0.133 | |
Condom use in the last sex |
No
| 0 (0/8) | 5.88 (1/17) | 4.55 (1/22) | 7.41 (2/27) | 0 (0/11) | 4.71 (4/85) | 0.839 | 0.912 |
Yes
| 0 (0/40) | 3.30 (3/91) | 2.08 (3/144) | 3.49 (11/3150 | 2.31 (8/346) | 2.67 (25/936) | 0.66 | 0.761 | |
Condom use in the last month |
Inconsistent
| 0 (0/22) | 2.33 (1/43) | 5.56 (3/54) | 6.76 (5/74) | 0 (0/63) | 3.52 (9/256) | 0.183 | 0.994 |
Consistent
| 7.41 (2/27) | 3.08 (2/65) | 3.60 (4/111) | 3.77 (10/265) | 1.69 (5/295) | 3.01 (23/763) | 0.38 | 0.115 | |
Drug use |
Yes
| 0 (0/2) | 0 (0/1) | 0 (0/6) | 18.18 (2/22) | 8.33 (1/12) | 9.38 (3/32) | 0.745 | 0.503 |
No
| 8.51 (4/47) | 5.56 (6/108) | 3.75 (6/160) | 2.71 (9/332) | 1.45 (5/346) | 3.02 (30/993) | 0.032 | 0.002 | |
Types of venues |
Low-paying
| 7.32 (3/41) | 7.59 (6/79) | 3.28 (4/122) | 5.59 (9/161) | 2.87 (5/174) | 4.68 (27/577) | 0.373 | 0.112 |
Medium-paying
| 0.00 (0/3) | 0.00 (0/19) | 6.25 (2/32) | 1.43 (2/140) | 0.55 (1/181) | 1.33 (5/375) | 0.135 | 0.267 | |
High-paying
| 20.00 (1/5) | 0.00 (0/11) | 0.00 (0/12) | 0.00 (0/21) | 0.00 (0/2) | 1.96 (1/51) | 0.052 | 0.063 | |
HIV knowledge |
<=5
| 10.34 (3/29) | 7.89 (3/38) | 4.81 (5/104) | 3.19 (6/188) | 1.85 (4/216) | 3.65 (21/575) | 0.087 | 0.003 |
>5
| 5.00 (1/20) | 4.17 (3/72) | 1.61 (1/62) | 3.23 (5/155) | 1.41 (2/142) | 2.66 (12/451) | 0.669 | 0.234 |
2010 | 2011 | 2012 | 2013 | 2014 | overall | p-value | p-trend | ||
---|---|---|---|---|---|---|---|---|---|
% (n/N) | % (n/N) | % (n/N) | % (n/N) | % (n/N) | % (n/N) | ||||
Age |
<=25 yr
| 10.0 (2/20) | 3.51 (/57) | 1.23 (1/81) | 1.26 (2/159) | 1.33 (2/150) | 1.93 (9/467) | 0.074 | 0.046 |
>25
| 6.9 % (2/29) | 15.09 (8/53) | 17.65 (15/85) | 13.59 (25/184) | 5.77 (12/208) | 11.09 (62/559) | 0.016 | 0.045 | |
Marital status |
Not married
| 10.71 (3/28) | 6.90 (4/58) | 3.23 (3/93) | 3.93 (7/178) | 1.27 (2/157) | 3.70 (19/514) | 0.084 | 0.008 |
Married
| 4.76 (1/21) | 11.54 (6/52) | 17.81 (13/73) | 12.12 (20/165) | 5.97 (12/201) | 10.16 (52/512) | 0.04 | 0.138 | |
Length of working |
<6 m
| 11.11 (1/9) | 5.63 (4/71) | 4.62 (3/65) | 2.56 (5/195) | 1.15 (2/174) | 2.92 (15/514) | 0.156 | 0.016 |
> = 6 m
| 7.50 (3/40) | 15.38 (6/39) | 12.12 (12/99) | 14.86 (22/148) | 6.52 (12/184) | 10.78 (55/510) | 0.111 | 0.312 | |
Education |
<MS
| 10.0 (3/30) | 12.9 (8/62) | 11.11 (10/90) | 15.38 (22/143) | 3.63 (7/193) | 9.65 (50/518) | 0.006 | 0.03 |
> = MS
| 5.26 (1/19) | 4.17 (2/48) | 8.11 (6/74) | 2.50 (5/200) | 4.24 (7/165) | 4.15 (21/506) | 0.361 | 0.475 | |
Community service |
Yes
| 8.51 (4/47) | 11.11 (8/72) | 9.27 (14/151) | 8.15 (26/319) | 3.86 (12/311) | 7.11 (64/900) | 0.076 | 0.01 |
No
| 0.00 (0/2) | 7.69 (2/26) | 13.33 (2/15) | 4.17 (1/24) | 4.26 (2/47) | 6.14 (7/114) | 0.729 | 0.467 | |
Condom use in the last sex |
No
| 12.50 (1/8) | 11.76 (2/17) | 13.64 (3/22) | 29.63 (8/27) | 0 (0/11) | 16.47 (14/85) | 0.195 | 0.726 |
Yes
| 7.5 (3/40) | 8.79 (8/91) | 9.03 (13/144) | 6.03 (19/315) | 4.05 (14/346) | 6.09 (57/936) | 0.199 | 0.032 | |
Condom use in the last month |
Inconsistent
| 9.09 (2/22) | 11.63 (5/43) | 16.67 (9/54) | 21.62 (16/74) | 6.35 (4/63) | 14.06 (36/256) | 0.109 | 0.9 |
Consistent
| 7.41 (2/27) | 7.69 (5/65) | 6.31 (7/111) | 3.77 (10/265) | 3.39 (10/295) | 4.46 (34/763) | 0.39 | 0.057 | |
Drug use |
Yes
| 0 (0/2) | 0 (0/1) | 16.67 (1/6) | 72.73 (8/11) | 16.67 (2/12) | 34.38 (11/32) | 0.024 | 0.559 |
No
| 8.51 (4/57) | 9.26 (10/108) | 9.38 (15/160) | 5.72 (19/332) | 3.47 (12/346) | 6.04 (60/993) | 0.046 | 0.006 | |
Types of venues |
Low-paying
| 9.76 (4/41) | 10.13 (8/79) | 12.30 (15/122) | 12.42 (20/161) | 5.17 (9/174) | 9.71 (56/577) | 0.172 | 0.153 |
Medium-paying
| 0.00 (0/3) | 5.26 (1/19) | 3.13 (1/32) | 5.00 (7/140) | 2.76 (5/181) | 3.73 (14/375) | 0.849 | 0.616 | |
High-paying
| 0.00 (0/5) | 0.00 (0/11) | 0.00 (0/12) | 0.00 (0/21) | 0.00 (0/2) | 0.00 (0/51) | n/a | n/a | |
HIV knowledge |
Low < =5
| 6.90 (2/29) | 7.89 (3/38) | 7.65 (9/104) | 9.04 (17/188) | 4.63 (10/216) | 7.13 (41/575) | 0.481 | 0.266 |
High >5
| 10.0 (2/20) | 9.72 (7/72) | 11.29 (7/62) | 6.45 (10/155) | 2.82 (4/142) | 6.65 (4/142) | 0.137 | 0.016 |
2010 | 2011 | 2012 | 2013 | 2014 | overall | p-value | p-trend | ||
---|---|---|---|---|---|---|---|---|---|
% (n/N) | % (n/N) | % (n/N) | % (n/N) | % (n/N) | % (n/N) | ||||
Age |
<=25 yr
| 0 (0/29) | 5.66 (3/53) | 3.53 (3/85) | 5.98 (11/184) | 3.37 (7/208) | 4.29 (24/559) | 0.498 | 0.849 |
>25 = 1
| 0 (0/20) | 0 (0/57) | 1.23 (1/81) | 0.63 (1/159) | 0.67 (1/150) | 0.64 (3/467) | 0.918 | 0.73 | |
Marital status |
Not Married
| 0 (0/28) | 0 (0/58) | 1.08 (1/93) | 2.81 (5/178) | 1.27 (2/157) | 1.56 (8/514) | 0.493 | 0.327 |
Married
| 0 (0/21) | 5.77 (3/52) | 4.11 (3/73) | 4.24 (7/165) | 2.99 (6/201) | 3.71 (19/512) | 0.757 | 0.761 | |
Length of working |
<6 m
| 0 (0/9) | 0 (0/71) | 0 (0/65) | 2.56 (5/195) | 1.72 (3/174) | 1.56 (8/514) | 0.46 | 0.209 |
> = 6 m
| 0 (0/40) | 7.69 (3/39) | 4.04 (4/99) | 4.73 (7/148) | 2.72 (5/184) | 3.73 (19/510) | 0.377 | 0.884 | |
Education |
<MS
| 0 (0/30) | 1.61 (1/62) | 3.33 (3/90) | 6.29 (9/143) | 3.11 (6/193) | 3.67 (19/518) | 0.301 | 0.317 |
> = MS
| 0 (0/19) | 4.17 (2/48) | 1.35 (1/74) | 1.50 (3/200) | 1.21 (2/165) | 1.58 (8/506) | 0.637 | 0.499 | |
Community service |
Yes
| 0 (0/47) | 2.78 (2/72) | 2.65 (4/151) | 3.45 (11/319) | 2.25 (7/311) | 2.67 (24/900) | 0.69 | 0.657 |
No
| 0 (0/2) | 3.85 (1/26) | 0 (0/15) | 4.17 (1/24) | 2.13 (1/47) | 2.63 (3/114) | 0.928 | 0.886 | |
Condom use in the last sex |
No
| 0 (0/8) | 0 (0/17) | 4.55 (1/22) | 3.70 (1/27) | 0 (0/11) | 2.35 (2/85) | 0.819 | 0.695 |
Yes
| 0 (0/40) | 3.30 (3/91) | 2.08 (3/144) | 3.49 (11/315) | 2.31 (8/346) | 2.67 (25/936) | 0.66 | 0.761 | |
Condom use in the last month |
Inconsistent
| 0 (0/22) | 2.33 (1/43) | 5.56 (3/54) | 6.76 (5/74) | 0 (0/63) | 3.52 (9/256) | 0.183 | 0.994 |
Consistent
| 0 (0/27) | 3.08 (2/65) | 0.90 (1/111) | 2.26 (6/265) | 2.71 (8/295) | 2.23 (17/763) | 0.727 | 0.414 | |
Drug use |
Yes
| 0 (0/2) | 100.0 (1/1) | 33.33 (2/6) | 63.64 (7/11) | 33.33 (4/12) | 43.75 (14/32) | 0.248 | 0.772 |
No
| 0 (0/47) | 1.85 (2/108) | 1.25 (2/160) | 1.51 (5/332) | 1.16 (4/346) | 1.31 (13/993) | 0.904 | 0.077 | |
Types of venues |
Low-paying
| 0.00 (0/41) | 3.80 (3/79) | 2.46 (3/122) | 4.35 (7/161) | 3.45 (6/174) | 3.29 (19/577) | 0.681 | 0.93 |
Medium-paying
| 0.00 (0/3) | 0.00 (0/19) | 3.13 (1/32) | 2.86 (1/32) | 1.10 (2/181) | 1.87 (7/375) | 0.732 | 0.716 | |
High-paying
| 0.00 (0/5) | 0.00 (0/11) | 0.00 (0/11) | 0.00 (0/21) | 0.00 (0/2) | 0.00 (0/51) | n/a | n/a | |
HIV knowledge |
Low < =5
| 0 (0/29) | 5.26 (2/38) | 2.88 (3/104) | 4.26 (8/188) | 3.24 (7/216) | 3.48 (20/575) | 0.756 | 0.705 |
High > 5
| 0 (0/20) | 1.39 (1/72) | 1.61 (1/62) | 2.58 (4/155) | 0.70 (1/142) | 1.55 (7/451) | 0.723 | 0.974 |
Predictive models for risk factors of different types of infection
HIV | Syphilis | HCV | ||||
---|---|---|---|---|---|---|
PREDICTORS | Univariate | Multivariablea
| Univariate | Multivariableb
| Univariate | Multivariablec,#
|
OR (95 % CI) | aOR (95 % CI)4
| OR (95 % CI) | aOR (95 % CI)4
| OR (95 % CI) | aOR (95 % CI)4
| |
Education | 2.68 (1.23,5.83)*** | 1.82 (0.79,4.20) | 2.47 (1.46,4.17)**** | 0.92 (0.49,1.73) | 2.37 (1.03,5.46)*** | 1.68 (0.59,4.77) |
Length of working | 0.31 (0.14,0.69)**** | 0.51 (0.21,1.25) | 0.25 (0.14,0.45)****** | 0.60 (0.30,1.18) | 0.41 (0.18,0.95)*** | 1.53 (0.50,4.67) |
Marital status | 0.73 (0.36,1.47) | N/A | 0.34 (0.20,0.58)****** | 0.96 (0.49,1.91) | 0.41 (0.18,0.95)*** | 0.78 (0.27,2.26) |
No condom use in the last sex act | 1.60 (0.55,4.68) | N/A | 3.04 (1.62,5.72)**** | 1.55 (0.68,3.53) | 0.88 (0.20,3.77) | N/A |
Inconsistent condom use in the past month | 1.31 (0.61,2.79) | N/A | 3.51 (2.14,5.74)****** | 2.27 (1.22,4.22)*** | 1.60 (0.70.3.63) | N/A |
HIV knowledge | 0.82 (0.46,1.45) | N/A | 0.84 (0.56,1.25) | N/A | 0.58 (0.30,1.13) | 0.63 (0.27,1.48) |
Syphilis infection | 3.17 (1.26,7.96)*** | 1.58 (0.56,4.46) | N/A | N/A | 9.05 (3.97,20.59)****** | 3.64 (1.20,11.00)*** |
HCV infection | 5.82 (1.89.17.90)**** | 4.14 (0.89,19.36) ** | 9.05 (3.97,20.60)****** | 4.78 (1.53,14.90)**** | N/A | N/A |
Age (continuous)2
| 1.05 (1.01,1.08)**** | 1.01 (0.98,1.05) | 1.09 (1.06,1.11)****** | N/A | 1.05 (1.01,1.09)**** | 1.01 (0.95,1.07) |
Age-younger (RCS)3
| N/A | N/A | N/A | 1.18 (1.01,1.37)*** | N/A | N/A |
Age-older (RCS)3
| N/A | N/A | N/A | 0.90 (0.76,1.07) | N/A | N/A |
Drug use | 3.32 (0.96, 11.51)* | 0.84 (0.15,4.82) | 8.15 (3.75,17.68)****** | 2.56 (0.87,7.49)** | 58.63 (24.14,142.39)****** | 44.01 (16.34,129.53)****** |
Venues types (medium vs. low) | 0.28 (0.11,0.72)*** | 0.46 (0.17,1.28) | 0.36 (0.20,0.66)**** | 0.83 (0.41,1.65) | 0.56 (0.23,1.34) | 0.34 (0.09,1.38) |
Venues types (high vs. low) | 0.41 (0.05,3.06) | 0.91 (0.11,7.46) | N/A | N/A | N/A | N/A |