Higher risk behaviour and rates of sexually transmitted diseases in Mwanza compared to Uganda may help explain HIV prevention trial outcomes.
OBJECTIVE
To determine to what extent the higher impact of treatment for sexually transmitted diseases (STD) on HIV incidence in Mwanza, Tanzania than in Rakai and Masaka, Uganda might be explained by baseline differences between the trial populations.


METHODS
A re-analysis of baseline data from the three trial populations comparing demography, sexual risk behaviour and HIV/STD epidemiology.


METHODS
Data were compared after age-standardization and adjustments for sample selection where necessary. STD rates were also adjusted for the sensitivities and specificities of the diagnostic techniques used.


RESULTS
Demographic patterns were similar across populations, apart from effects of AIDS on fertility and mortality (including widowhood) in Uganda. Higher sexual risk behaviours, including younger age of sexual debut, higher numbers of recent partners and lower frequency of condom use, were apparent in Mwanza compared to Masaka and Rakai. High-titre serological syphilis, gonorrhoea, chlamydia infection and trichomoniasis were all more prevalent in Mwanza, except for chlamydia infection in males. There was little difference between sites in the seroprevalence of Herpes simplex virus type-2. Age patterns in the prevalence of short-duration STD and current risk behaviours were similar across sites but all-titre serological syphilis was more prevalent among older participants in Rakai and Masaka than Mwanza.


CONCLUSIONS
Differences between trial populations included higher reported risk behaviour and higher rates of curable STD in Mwanza compared to Rakai and Masaka. These differences probably relate to previous reductions in risk behaviour in Uganda and may explain, at least in part, the contrasting results of these trials.
Orroth
Kate K
KK
London School of Hygiene and Tropical Medicine, London, UK. kate.orroth@lshtm.ac.uk
Korenromp
Eline L
EL
White
Richard G
RG
Gavyole
Awene
A
Gray
Ron H
RH
Muhangi
Lawrence
L
Sewankambo
Nelson K
NK
Quigley
Maria
M
Wawer
Maria J
MJ
Whitworth
James A
JA
Grosskurth
Heiner
H
Habbema
J Dik
JD
Hayes
Richard J
RJ
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002690:Chlamydia Infections / Q000453:epidemiology; D002692:Chlamydia trachomatis; D017280:Condoms; D005260:Female; D006069:Gonorrhea / Q000453:epidemiology; D015658:HIV Infections / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D015994:Incidence; D008297:Male; D017533:Marital Status; D008875:Middle Aged; D015995:Prevalence; D012309:Risk-Taking; D012423:Rural Health; D017678:Sex Distribution; D012725:Sexual Behavior / Q000523:psychology*; D012747:Sexual Partners / Q000523:psychology; D012749:Sexually Transmitted Diseases / Q000188:drug therapy / Q000453:epidemiology*; D013636:Tanzania / Q000453:epidemiology; D016896:Treatment Outcome; D014247:Trichomonas Vaginitis / Q000453:epidemiology; D014454:Uganda / Q000453:epidemiology