Socioecological differences in factors associated with inconsistent condom use with female sex workers and casual partners: an observational study of heterosexual men attending an anonymous HIV testing clinic in Singapore.

Sexual practices among heterosexual men may differ between female sex workers (FSWs) and casual partners. We surveyed 203 heterosexual men and investigated the attributes associated with inconsistent condom use among them. Lower educational attainment was positively associated with inconsistent condom use with FSWs (adjusted prevalence ratio (aPR) 2.63; P = 0.018) and casual partners (aPR 1.55; P = 0.022), whereas early age of sexual debut (aPR 3.00; P = 0.012) and alcohol use during sex (aPR 7.95; P < 0.001) were positively associated with inconsistent condom use with FSWs. Socioecological factors may explain such differences.

Quality improvement: experience of a sexually transmitted infection clinic in Singapore.

SUMMARY: Over the past two years, the Department of Sexually Transmitted Infection Control Clinic (DSC) in Singapore has embarked on a programme to review and enhance its quality improvement programmes. A thorough review of its day-to-day operations was conducted, infection control processes and standard operating procedures. It capitalized on its use of computerized medical records to improve documentation and patient screening. DSC introduced risk-management protocols and revised patient, staff and workplace safety guidelines. These measures have resulted in benefits such as reduced prescription errors, fewer patient complaints and active clinical practice improvement programmes. In January 2008, DSC, along with its parent hospital the National Skin Centre, became the first ambulatory health-care facility in Singapore, and also among the first few outside the United States to be accredited by the Joint Commission International.

Chinese attitudes toward cleft lip and palate: effects of personal contact.

OBJECTIVE: The purpose of this study was to investigate the effect of personal contact on the attitudes of individuals towards persons with cleft lip and palate (CLP) and the possible cultural differences in these attitudes for Chinese respondents living in Hong Kong. DESIGN: Chinese parent, teacher, and employer groups were administered a cleft lip and palate attitudinal questionnaire and the Scale of Attitudes Toward Disabled Persons inventory. SUBJECTS: Thirty-nine parents of children with CLP, 27 teachers of children with CLP, and 37 employers with no previous contact with individuals with CLP participated in the study. RESULTS: The results showed significant intergroup differences on several items involving beliefs concerning emotional health, social development, and employment-related barriers for individuals with CLP, and whether such individuals should seek nonmedical help to treat speech problems. Employers showed a comparatively less favorable attitude to persons with CLP than the two other groups. CONCLUSION: Parent, teacher, and employer groups in the Chinese community studied showed differences in their attitudes towards individuals with CLP. The findings suggest the need for further community health education to help develop more positive attitudes towards disabled persons in general, as well as programs targeted at reducing negative stereotyping of adults and children with CLP.

An epidemiological and knowledge, attitudes, beliefs and practices study of sexually transmitted infections in older men.

INTRODUCTION: This study was conducted to determine the disease patterns of sexually transmitted infections (STI) in older men, as well as to gather information on their knowledge, attitudes, beliefs and sexual practices. METHODS: A prospective study was carried out from January to June 2005 in men aged 50 years or older who attended the Department of STI Control clinic. RESULTS: There were 104 men enrolled. The majority (92.3 percent) were Chinese, and 62.5 percent were aged between 50 and 59 years, 25.9 percent between 60 and 69 years, and 11.5 percent aged 70 years or older. The patients were predominantly heterosexual, and had fairly low levels of education--85.6 percent of the patients had received primary or secondary school level of education. Majority (79.8 percent) of the men had been sexually active in the preceding six months, and 37.3 percent had paid sex during that time. 29.8 percent of men reported having taken drugs such as sildenafil (Viagra, Pfizer, New York, NY, USA) or similar drugs such as vardenafil (Levitra, Bayer, Wuppertal, Germany) or tadalafil (Cialis, Eli Lilly, Indianapolis, IN, USA). 56.7 percent of the men had active infections, with non-gonococcal urethritis (15.4 percent), genital warts (12.5 percent) and gonorrhoea (10.6 percent) being the commonest. Generally, condom usage was accepted as an effective way to prevent transmission of STI. However, many of the men surveyed felt that condom usage reduced their sexual pleasure, and 38.5 percent felt that condoms were inconvenient. There were also areas of human immunodeficiency virus (HIV) knowledge that were lacking. Most patients listed the media as their main source of knowledge about STI and HIV. CONCLUSION: Older males attending the clinic remain at significant risk of STI and targeted educational efforts are warranted.

Genital herpes in a sexually-transmitted infection clinic in Singapore: a 1-year retrospective study.

INTRODUCTION: This study describes the clinical features of genital herpes seen in a sexually-transmitted infection (STI) clinic in Singapore and the characteristics of the affected population. The distribution of herpes simplex virus (HSV) subtypes within the population, correlation of HSV culture result with duration of disease and prescribing habits of doctors were also examined. MATERIALS AND METHODS: This is a retrospective study of cases of genital herpes seen at the Department of Sexually-transmitted Disease Control (DSC) clinic over a 1-year period. All records of clinically diagnosed HSV genital infections at the DSC clinic in 2001 were retrieved and reviewed and the data collated. RESULTS: There were 324 cases of genital herpes, of which 153 (47.2%) were first-episode and 171 (52.8%) were recurrent HSV infections. There were 259 males and 65 females; their mean age was 35.2 years (range, 17 to 75 years). Of the 241 cases with positive culture results, 28 (11.6%) tested positive for herpes simplex virus type 1 (HSV-1) and 213 (88.4%) were positive for herpes simplex virus type 2 (HSV-2). HSV-1 accounted for 19.3% of first-episode and 4.7% of recurrent infections. HSV-2 accounted for 80.7% of first-episode and 95.3% of recurrent infections. Cultures taken from lesions < or = 4 days, between 5 and 7 days and > 7 days of onset were positive in 79.2%, 75.7% and 75% of cases, respectively. Oral acyclovir was prescribed more commonly in females (53.8%) than in males (21.6%). CONCLUSION: Genital herpes is a common STI seen at the DSC clinic. HSV-2 is the most common cause of genital herpes and accounts for most of the recurrent cases seen.

Ischaemia-reperfusion is an event triggered by immune complexes and complement.

BACKGROUND: Reperfusion injury is a common clinical problem that lacks effective therapy. Two decades of research implicating oxygen free radicals and neutrophils has not led to a single successful clinical trial. METHODS: The aim was to review new clinical and preclinical data pertaining to the alleviation of reperfusion injury. A review of the literature was undertaken by searching the MEDLINE database for the period 1966-2003 without language restrictions. RESULTS AND CONCLUSION: Evidence now points to complement and immune complexes as critical players in mediating reperfusion injury. Ischaemia is postulated to induce a phenotypical cellular change through the surface expression of a neoantigen. Preformed circulating natural IgM antibodies are then trapped and complement is activated. Final events leading to reperfusion injury include formation of the membrane attack complex and mast cell degranulation.

Sexually transmitted infections in Singapore teenagers.

INTRODUCTION: This is a review of sexual knowledge, behaviour and the extent of sexually transmitted infections (STI), including human immunodeficiency virus (HIV) infection, in Singapore adolescents. METHODS: Data were retrieved from relevant studies, reports and statistics concerning STI and HIV in Singapore. RESULTS: For many reasons, adolescents are at a higher risk of acquiring STI and HIV infections. Adolescents in Singapore are still relatively conservative in their sexual attitudes and behaviour. Most of those who had sex never used condoms. Fortunately, the incidence of STI and HIV infections among adolescents is relatively low. However, this may be changing, and there is a proportion of individuals who exhibit higher risk behaviours. CONCLUSIONS: In this age of rapidly changing morals and values, accurate information and skills need to be provided to young people to ensure that they are adequately prepared to protect themselves from acquiring STI/HIV infection.

Sexually transmitted diseases in the older population in Singapore.

BACKGROUND: Sexually transmitted diseases (STDs) in persons older than 50 years are rarely studied because STDs are more common in young people. AIM: To study the distribution and types of STDs in older persons, defined in our study as individuals aged 50 years or older. METHOD: Retrospective analysis of surveillance data for diseases notified under the Infectious Disease Act, which include syphilis, gonorrhoea, non-gonococcal urethritis (NGU), vaginal discharge and chancroid. Human immunodeficiency virus (HIV) infections were not included. Data from notifications of diseases, such as genital herpes and genital warts, which are not compulsory, were also analysed. Period of study was from January 1996 to December 2000. RESULTS: During the study period, STD notifications for persons aged 50 years and older accounted for 7.6% of all notifications. Among these older persons, males were predominantly affected. The most common disease notified in older persons was gonorrhoea (600 cases), followed by non-infectious syphilis (578 cases) and NGU (339 cases). There were 76 cases of infectious syphilis. The age-specific disease rates for this group of older patients were as follows (number of cases per 100,000 patients per year): gonorrhoea-17.61, non-infectious syphilis-16.96, infectious syphilis-2.23, NGU-20.66, genital warts-6.92 and genital herpes-7.33. CONCLUSION: Although STDs occur mainly in the young, it affects a small but significant proportion of persons aged 50 years and older. A better understanding of the epidemiology of STDs in these population is important for reducing STD morbidity and improving STD care.

The epidemiology and treatment of anogenital warts in Singapore: a retrospective evaluation.

INTRODUCTION: A retrospective study in the referral centre for sexually transmitted infections (STIs) in Singapore to describe the epidemiology and treatment outcome of patients with anogenital warts. SUBJECTS AND METHODS: We reviewed the case records of 301 patients with anogenital warts who were seen over a 1-year period (1999). We also attempted to interview every patient by telephone to find out if they had any clinical recurrences for which treatment was sought elsewhere. RESULTS: There were 255 males and 46 females with a mean age of 34 years. Two hundred and nineteen (72.8%) presented with symptoms lasting 12 weeks or less. In males, warts occurred most frequently in the preputial cavity (52.5%) and on the penile shaft (40.8%). In females, they occurred most frequently on the external genitalia (91.3%). Two hundred and thirty-five males were treated with cryotherapy and 69% (95% CI, 62.6% to 74.8%) achieved clinical resolution after a mean of 6 treatment cycles. Seven males were treated with podophyllin 0.25% in ethanol and 71% (95% CI, 29.0% to 96.3%) were clinically cured after a mean of 4 treatment cycles. Thirty-nine females were treated with cryotherapy and 67% (95% CI, 49.8% to 80.9%) achieved clinical cure after a mean of 4 treatment cycles. Of the 290 patients treated at the centre, 212 (73%; 95% CI, 67.3% to 77.8%) patients (184 males, 28 females) achieved clinical cure after a mean of 7 weeks (range, 1 to 34 weeks); 90% (95% CI, 86.0% to 93.2%) of them by 15 weeks. Seven-two patients defaulted follow-up and 6 responded partially to treatment. Of the 212 patients who achieved clinical cure, 195 were interviewed by telephone, on an average, 17.7 months after clinical resolution. Thirty-seven (19%; 95% CI, 13.7% to 25.2%), all males, relapsed clinically after a mean of 100 days (range, 5 to 329 days); 90% (95% CI, 84.6% to 93.6%) relapsed by 228 days. CONCLUSIONS: Podophyllin 0.25% in ethanol was the most cost-effective treatment for males. One in 5 patients had a recurrence of their warts and most had their recurrence within 8 months of initial resolution.

"Economy class" stroke syndrome?

The authors report three cases of ischemic stroke in young adults that occurred during or after an airplane flight. Workup was negative for any cause of stroke other than the presence of a patent foramen ovale (PFO). There is an increasing awareness of deep vein thrombosis and pulmonary embolism occurring in relation to long flights. Individuals with a PFO under these circumstances may be vulnerable to stroke from paradoxic embolism. "Economy class" stroke syndrome may be underdiagnosed and is an eminently preventable cause of stroke.

Real-time size distribution, concentration, and biomass measurement of marine phytoplankton with a novel dual-beam laser fluorescence Doppler cytometer.

A novel cytometer is reported for measuring particle-size distribution, concentration, and biomass of marine phytoplankton containing chlorophyll a. The system utilizes optical fibers to carry light to and from a flow tube for measuring phytoplankton taken directly from the ocean. A unique feature of this system is in the simple optical detection scheme for which sample handling and preparation are not required. This simplicity makes the system especially suitable for field measurements. The system utilizes sophisticated digital signal processors to handle and reduce the large amount of data gathered. The signal-processing algorithms are vigorously streamlined to process the signals in real time, thus computing size and flow velocity information instead of logging the raw data. The high efficiency of the signal processors gives the system a performance throughput of ~250 particles/s. The system was tested both in the laboratory and in the field, yielding good discrimination of size distribution and sensitivity of concentration.

Paradoxical activational effects of a corticotropin-releasing factor-binding protein "ligand inhibitor" in rat brain.

The corticotropin-releasing factor-binding protein is distinct from known corticotropin-releasing factor receptors, but can bind the peptide and neutralize its biological actions. Recent interest has centered about the therapeutic potential of "ligand inhibitors" of binding protein action, synthetic corticotropin-releasing factor fragments which are inactive at corticotropin-releasing factor receptors, but can displace the peptide from the binding protein, thereby increasing levels of free corticotropin-releasing factor. To identify sites of action of such ligands, the distribution of Fos expression seen following intracerebroventricular administration of rat/human corticotropin-releasing factor(6-33) (5-50 microg) was charted in relation to corticotropin-releasing factor-binding protein and receptor expression. It was expected that Fos induction would mimic aspects of the distribution of the two known corticotropin-releasing factor receptors, but the far greater correspondence was seen with that of the binding protein itself. This included neurons in the isocortex, the olfactory system, amygdala and a number of discrete brainstem cell groups; many Fos-immunoreactive neurons in each were found to co-express corticotropin-releasing factor-binding protein messenger RNA. Subsets of activated neurons co-expressed Type 1 corticotropin-releasing factor receptor messenger RNA, though these were largely limited to cell groups that also express the corticotropin-releasing factor-binding protein, and where binding protein immunoreactivity and Type 1 receptor transcripts were found to co-exist. Responsive neurons displaying Type 2 corticotropin-releasing factor receptor message were seen reliably only in the lateral septal nucleus. These findings support only a limited capacity of the ligand inhibitor to activate neurons bearing corticotropin-releasing factor receptors. The more pervasive activation seen among neurons that express the corticotropin-releasing factor-binding protein may be indicative of an unexpected role for this protein in signaling by corticotropin-releasing factor-related peptides.

Effects of selective sinoaortic denervations on phenylephrine-induced activational responses in the nucleus of the solitary tract.

Intravenous administration of phenylephrine provokes a pattern of cellular activation in the nucleus of the solitary tract that resembles the central distributions of primary baroreceptor afferents supplied by the carotid sinus and aortic depressor nerves. Transganglionic transport and denervation methods were used in an experimental setting to test the dependence of phenylephrine-induced Fos immunoreactivity on the integrity of buffer nerve afferents, and to identify the subregions of the nucleus of the solitary tract supplied by each. Cholera toxin B-horseradish peroxidase injections into either or both nerves revealed terminal labeling concentrated in, but not restricted to, the dorsal commissural part of the nucleus of the solitary tract at the level of the apex of calamus scriptorius, and extending into the dorsal subnucleus at the level of the area postrema. Preferential ramifications of carotid sinus and aortic depressor nerve afferents at the levels of the commissural part of the nucleus and the area postrema, respectively, were reflected in the extent to which labeled fibers comingled with neurons exhibiting phenylephrine-induced Fos in dual labeling experiments. Complete sinoaortic denervation reduced by 90% the number of neurons exhibiting drug-induced Fos expression. Selective carotid and aortic sinus denervations effected partial reductions manifest preferentially in the caudal and rostral foci of the distribution, respectively. Reduced activational responses at the level of the area postrema of aortic sinus-denervated rats were accompanied by a reduction in cellular nicotinamide adenine dinucleotide phosphate-diaphorase activity in this region. Animals killed 30 days after complete sinoaortic denervation displayed no evidence of recovery of phenylephrine-induced Fos, while the strength and distribution of the response in rats that received selective carotid sinus denervation were indistinguishable from those seen in controls. These findings (i) support the dependence of phenylephrine-induced Fos expression on the integrity of carotid sinus and aortic depressor nerve afferents, (ii) provide anatomical and functional evidence that the two buffer nerves distribute differentially within the nucleus of the solitary tract, and (iii) implicate central reorganization as a likely basis for functional recovery of baroreflex mechanisms following partial sinoaortic denervation.

Distribution of mRNAs encoding CRF receptors in brain and pituitary of rat and mouse.

Two G protein-coupled receptors have been identified that bind corticotropin-releasing factor (CRF) and urocortin (UCN) with high affinity. Hybridization histochemical methods were used to shed light on controversies concerning their localization in rat brain, and to provide normative distributional data in mouse, the standard model for genetic manipulation in mammals. The distribution of CRF-R1 mRNA in mouse was found to be fundamentally similar to that in rat, with expression predominating in the cerebral cortex, sensory relay nuclei, and in the cerebellum and its major afferents. Pronounced species differences in distribution were few, although more subtle variations in the relative strength of R1 expression were seen in several forebrain regions. CRF-R2 mRNA displayed comparable expression in rat and mouse brain, distinct from, and more restricted than that of CRF-R1. Major neuronal sites of CRF-R2 expression included aspects of the olfactory bulb, lateral septal nucleus, bed nucleus of the stria terminalis, ventromedial hypothalamic nucleus, medial and posterior cortical nuclei of the amygdala, ventral hippocampus, mesencephalic raphe nuclei, and novel localizations in the nucleus of the solitary tract and area postrema. Several sites of expression in the limbic forebrain were found to overlap partially with ones of androgen receptor expression. In pituitary, rat and mouse displayed CRF-R1 mRNA signal continuously over the intermediate lobe and over a subset of cells in the anterior lobe, whereas CRF-R2 transcripts were expressed mainly in the posterior lobe. The distinctive expression pattern of CRF-R2 mRNA identifies additional putative central sites of action for CRF and/or UCN. Constitutive expression of CRF-R2 mRNA in the nucleus of the solitary tract, and stress-inducible expression of CRF-R1 transcripts in the paraventricular nucleus may provide a basis for understanding documented effects of CRF-related peptides at a loci shown previously to lack a capacity for CRF-R expression or CRF binding. Other such "mismatches" remain to be reconciled.

Fine structure and plasticity of barosensitive neurons in the nucleus of solitary tract.

Intravenous phenylephrine (PE) activates neurons in the nucleus of the solitary tract (NTS) whose distribution conforms to those of central projections of the carotid sinus and aortic depressor nerves. This was exploited to permit fine structural characterization of cells presumed to compose the first station in the processing of arterial baroreceptor input, and their responses to stimulation. Rats were perfused at varying intervals after PE injection, and sections through the baroreceptor afferent zone of the NTS prepared for preembedding immunolocalization of Fos-immunoreactivity. Labeled neurons composed a continuous strip extending from the dorsal part of the commissural NTS (NTScom) to the dorsal subnucleus at the level of the area postrema (NTSap). PE-sensitive neurons in these regions were medium-sized, round to ovoid in shape, with scant cytoplasm and an unremarkable complement of organelles. Distinctive features included extensively invaginated nuclei and well-developed Golgi apparati; Fos-ir cells in the NTSap were distinguished from those in NTScom by virtue of better-developed rough endoplasmic reticulum and Golgi, and less convoluted nuclei. Proximal synaptic input to PE-sensitive neurons was sparse and was provided by terminals containing predominantly small, clear synaptic vesicles that formed mainly symmetric junctions with somata and primary dendrites. Prolonged stimulation was accompanied by accentuation of nuclear invaginations, marked accumulation of heterochromatin at their apices, and evidence of enhanced Golgi activity (vesicular budding). These may represent adaptations to facilitate changes in gene expression, to maintain neurotransmitter availability, or both, in the face of a persistent hypertensive challenge.

The causes and risk of stroke in patients with asymptomatic internal-carotid-artery stenosis. North American Symptomatic Carotid Endarterectomy Trial Collaborators.

BACKGROUND: The causes of stroke in patients with asymptomatic carotid-artery stenosis have not been carefully studied. Information about causes might influence decisions about the use of carotid endarterectomy in such patients. METHODS: We studied patients with unilateral symptomatic carotid-artery stenosis and asymptomatic contralateral stenosis from 1988 to 1997. The causes, severity, risk, and predictors of stroke in the territory of the asymptomatic artery were examined and quantified. RESULTS: The risk of stroke at five years after study entry in a total of 1820 patients increased with the severity of stenosis. Among 1604 patients with stenosis of less than 60 percent of the luminal diameter, the risk of a first stroke was 8.0 percent (1.6 percent annually), as compared with 16.2 percent (3.2 percent annually) among 216 patients with 60 to 99 percent stenosis. In the group with 60 to 99 percent stenosis, the five-year risk of stroke in the territory of a large artery was 9.9 percent, that of lacunar stroke was 6.0 percent, and that of cardioembolic stroke 2.1 percent. Some patients had more than one stroke of more than one cause. In the territory of an asymptomatic occluded artery (as was identified in 86 patients), the annualized risk of stroke was 1.9 percent. Strokes with different causes had different risk factors. The risk factors for large-artery stroke were silent brain infarction, a history of diabetes, and a higher degree of stenosis; for cardioembolic stroke, a history of myocardial infarction or angina and hypertension; for lacunar stroke, age of 75 years or older, hypertension, diabetes, and a higher degree of stenosis. CONCLUSIONS: The risk of stroke among patients with asymptomatic carotid-artery stenosis is relatively low. Forty-five percent of strokes in patients with asymptomatic stenosis of 60 to 99 percent are attributable to lacunes or cardioembolism. These observations have implications for the use of endarterectomy in asymptomatic patients. Without analysis of the risk of stroke according to cause, the absolute benefit associated with endarterectomy may be overestimated.

A prospective study on condom slippage and breakage among female brothel-based sex workers in Singapore.

BACKGROUND: Concerns about the effectiveness of condoms in preventing sexually transmitted diseases have been raised. Data are lacking on condom failure and its associated factors among sex workers in Southeast Asia. GOAL: To assess factors associated with condom breakage and slippage. STUDY DESIGN: A prospective study on condom breakage and slippage over a 1-day period was conducted among 219 female brothel-based sex workers in Singapore in 1997. RESULTS: Condom breakage and slippage rates among 1,885 episodes of condom use were 1.2% (95% CI, 0.7-1.8) and 2.1% (95% CI, 1.2-3.0), respectively. After adjusting for intracluster effects and confounders, condom breakage and slippage were significantly associated with duration of sex work and spontaneity of clients to use condoms. CONCLUSION: Condom use among sex workers should be promoted in view of the low failure rates. Strategies to reduce condom breakage and slippage should be directed at sex workers with increased risk of condom failure.

Factors associated with condom use for oral sex among female brothel-based sex workers in Singapore.

BACKGROUND AND OBJECTIVE: The prevalence of oral sex increased from 27.1% in 1992 to 81.1% in 1997, with a concomitant increase in pharyngeal gonorrhea, among female sex workers in Singapore. The extent of condom use for oral sex among them is unknown. GOAL: To determine the prevalence of and factors associated with consistent condom use during oral sex. STUDY DESIGN: A cross-sectional study of 225 women randomly selected from the surveillance scheme register of female brothel-based sex workers with a history of oral sex documented in their medical records. RESULTS: Slightly more than half (56.9%) consistently used condoms for oral sex compared to 97% for vaginal sex. Condom use was significantly higher among middle than high class sex workers (adjusted rate ratio: 1.52, 95% CI: 1.01-2.29) and those with negotiation skills (adjusted rate ratio: 1.95, 95% CI: 1.32-2.07). CONCLUSION: Sex workers should be taught skills to negotiate condom use for oral sex.

PIP: Oral sex, which was once considered an uncommon sexual behavior, has become a relatively common practice. Its prevalence increased from 27.1% in 1992 to 81.1% in 1997, with a concomitant increase in pharyngeal gonorrhea among female sex workers in Singapore. The extent of condom use for oral sex among them is unknown. This cross-sectional study determined the prevalence of, and factors associated with, consistent condom use for oral sex among 225 female brothel-based sex workers, with paying clients in Singapore. Results indicated that slightly more than half (56.9%) consistently used condoms for oral sex compared to 97% for vaginal sex. Condom use was significantly associated with class of sex workers and negotiation skills. Significantly higher rates of condom use were found among high-class sex workers (adjusted rate ratio: 1.52; 95% CI: 1.01-2.29) and those with negotiation skills (adjusted rate ratio: 1.95; 95% CI: 1.32-2.07). In light of these findings, it is suggested that future interventions provide training to sex workers, particularly high-class ones, on negotiation concerning oral sex.

Sexually transmitted diseases and condom use among female freelance and brothel-based sex workers in Singapore.

BACKGROUND AND OBJECTIVES: Most studies in Asia exclude freelance female sex workers because of difficulties in access and the illegality of their work. Data are lacking on their risk behaviors. GOAL: To compare sexually transmitted disease (STD) rates, condom use, and health screening behavior between freelance and brothel-based sex workers in Singapore. STUDY DESIGN: This is a cross-sectional survey of 111 free-lance sex workers arrested from November 1996 to March 1997 for illicit prostitution and 333 randomly selected brothel-based sex workers. All were tested for STDs. RESULTS: STDs were significantly more prevalent among freelance than brothel-based sex workers (34.8% vs. 24.0%). Inconsistent condom use was significantly higher among freelance than brothel-based sex workers and was significantly associated with younger age, decreasing number of clients, and perception of non-condom use among peers. CONCLUSION: Educational programs to promote condom use should target freelance sex workers and their clients.

PIP: This study compares the prevalence of sexually transmitted diseases (STDs), condom use, and health-screening behavior between freelance and brothel-based sex workers in Singapore. A total of 111 female freelance sex workers arrested from November 1996 to March 1997 for illicit prostitution were interviewed; 333 brothel-based sex workers served as the comparison group for the analysis. STD test results revealed that freelance sex workers (34.8%) have higher STD rates than brothel-based sex workers (24%). The two most common STDs in both groups were chlamydial cervicitis and syphilis. Moreover, condom use was significantly lower among freelance sex workers than brothel-based sex workers and was associated with younger age (25 years old), decreasing number of clients, and perception of non-condom use among peers. In addition, freelance workers were more educated and had equally high knowledge on STDs and AIDS. Since most of these freelance workers practice high-risk behaviors and poor health screening behaviors such as not going for regular medical check-ups, STD services and education programs should target this group.