The disproportionate burden of HIV and STIs among male sex workers in Mexico City and the rationale for economic incentives to reduce risks.
BACKGROUND
The objective of this article is to present the rationale and baseline results for a randomized controlled pilot trial using economic incentives to reduce HIV and sexually transmitted infection (STI) risk among male sex workers (MSWs) in Mexico City.


METHODS
Participants (n=267) were tested and treated for STIs (chlamydia, gonorrhoea, syphilis and HIV) and viral hepatitis (hepatitis B and C), received HIV and STI prevention education and were randomized into four groups: (1) control, (2) medium conditional incentive ($50/six months), (3) high conditional incentive ($75/six months) and (4) unconditional incentive ($50/six months). In the conditional arms, incentives were contingent upon testing free of new curable STIs (chlamydia, gonorrhoea and syphilis) at follow-up assessments.


RESULTS
Participants' mean age was 25 years; 8% were homeless or lived in a shelter, 16% were unemployed and 21% lived in Mexico City less than 5 years. At baseline, 38% were living with HIV, and 32% tested positive for viral hepatitis or at least one STI (other than HIV). Participants had a mean of five male clients in the previous week; 18% reported condomless sex with their last client. For 37%, sex work was their main occupation and was conducted mainly on the streets (51%) or in bars/discotheques (24%) and hotels (24%). The average price for a sex transaction was $25 with a 35% higher payment for condomless sex.


CONCLUSIONS
The findings suggest that economic incentives are a relevant approach for HIV prevention among MSWs, given the market-based inducements for unprotected sex. This type of targeted intervention seems to be justified and should continue to be explored in the context of combination prevention efforts.
Brown University School of Public Health, Providence, RI, USA; Instituto Nacional de Salud Pública (INSP), Cuernavaca, Mexico; omar_galarraga@brown.edu.
Omar
O
Galárraga
Instituto Nacional de Salud Pública (INSP), Cuernavaca, Mexico.
Sandra G
SG
Sosa-Rubí
Clínica Especializada Condesa, Mexico City, Mexico.
Andrea
A
González
Clínica Especializada Condesa, Mexico City, Mexico.
Florentino
F
Badial-Hernández
Instituto Nacional de Salud Pública (INSP), Cuernavaca, Mexico.
Carlos J
CJ
Conde-Glez
Clínica Especializada Condesa, Mexico City, Mexico.
Luis
L
Juárez-Figueroa
Instituto Nacional de Salud Pública (INSP), Cuernavaca, Mexico.
Sergio
S
Bautista-Arredondo
Brown University School of Public Health, Providence, RI, USA; Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa.
Caroline
C
Kuo
Brown University School of Public Health, Providence, RI, USA.
Don
D
Operario
Brown University School of Public Health, Providence, RI, USA; The Fenway Institute, Beth Israel Deaconess Medical Center, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
Kenneth H
KH
Mayer
D000293:Adolescent; D000328:Adult; D018562:Disease Transmission, Infectious / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D009042:Motivation; D018570:Risk Assessment; D040242:Risk Reduction Behavior; D060386:Sex Workers; D012749:Sexually Transmitted Diseases / Q000453:epidemiology* / Q000517:prevention & control*; D055815:Young Adult
HIV/STI prevention; Mexico; compensating differential; conditional cash transfer; conditional economic incentives; male sex workers; men who have sex with men; risk premium