Transcript Folie 1

Coinfection and Risk Factors for Four Prevalent STIs in Ireland
1F
Shiely, 2M Horgan and 3K Hayes
1Department
of Epidemiology & Public Health UCC
2Department of Medicine UCC and Department of Infectious Diseases CUH
3Department of Infectious Diseases UL
Background
Little has changed in STI epidemiology in Ireland since 2000. Three STIs comprise approximately 90% of
notifications; ano-genital warts, chlamydia trachomatis and non-specific urethritis. Still, Ireland does not have a
national sexual health strategy, despite the recent increasing trends in STI and HIV acquisition. Our objective was to
compare the risk factors for four sexually transmitted infections in attendees at two STI clinics and examine the
incidence of coinfection.
Methods
Diagnostic, demographic and behavioural information data on attendees at two clinics in southwest Ireland were collected
from January 1999-July 2009. Chi-squared tests examined the differences in demographic and behavioural characteristics
across clinics, stratified by sex. Risk factors associated with first episodes of external genital warts (EGW), genital herpes
simplex viral infection (HSV), non-specific urethritis (NSU) and chlamydia (CT) were investigated using the presence of
each of these sexually transmitted infections as the outcome variable in separate multiple logistic regression models.
Results
22,705 first time patients, excluding HIV, received 26,824 diagnoses. 49% of patients in clinic 1 were female (mean age =
27.3 years (SD = 7.6 years)) and 55% of clinic 2 was female (mean age 27.3 years (SD = 8.3). Male and female
attendees differed in both clinics by age, no. of sexual partners in last 12 months, alcohol use and EGW and CT diagnosis
(p <0.05). Males differed by sexual preference, no. of partners in the last 3 months and drug use (p <0.05). Females
differed by condom use, marital status (p < 0.05). 50% of patients were screened and not diagnosed with a notifiable STI.
EGW accounts for 17% of first diagnoses and is also most likely to be associated with a coinfection. Concurrent EGW
and CT is more prevalent in females. HSV diagnoses are >75% female and NG is almost exclusively diagnoses in males
(91%). 60% of CT diagnoses are asymptomatic. EGW, CT, HSV, NSU were examined by univariate analysis and
subsequently multivariable analyses separately for males and females. Young age is a risk factor for all four STIs.
Inconsistent condom use, smoking and an increase in number of partners were also significant risk factors. Multiple
partners decrease the risk of viral infection with EGW but increase the risk of bacterial infection.
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Figures: Risk factors for EGW showing odds ratio with accompanying 70%, 80%, 90%, 95% and 99% confidence intervals: males (left) females (right)
Conclusions
Our findings suggest that while targeting high-risk groups in STI prevention strategies is appropriate for bacterial STIs, it may
have minimal impact on the prevalence of viral STIs. Prevention strategies that target youth, bacterial STIs and high-risk
behaviour, including sexual, alcohol and drugs, may be effective in reducing STI incidence in Ireland.