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S S Weir

Publications and source records attributed to S S Weir.

At least 19 recordsLinked to original sources
PubMed2004

Where the action is: monitoring local trends in sexual behaviour.

OBJECTIVES: To assess the role in an overall monitoring strategy of the PLACE method of estimating local trends in sexual behaviour among individuals at social venues in areas at increased risk of HIV transmission. METHODS: Public venues identified by community informants as places where people meet new sexual partners were visited and characterised in Karaganda, Kazakhstan, in 2002 and 2003, and in a township in South Africa in 2000 and 2003. At a subset of venues, a representative sample of individuals socialising at the venue were interviewed about their sexual behaviour. The age distribution and partnerships rates of those socialising at these venues were compared by year and with national data from Kazakhstan and South Africa obtained via household surveys. RESULTS: Women and men socialising at venues were younger and had higher rates of new and concurrent partnerships than men and women interviewed in national household surveys. There was little apparent change in sexual behaviour between 2002 and 2003 in Karaganda. In the South African township, there was a reduction in sexual partnerships and an increase in condom use, possibly due to a local AIDS prevention programme. CONCLUSION: Findings from the PLACE method supplement national data on sexual behaviours with data from key populations in high transmission areas, inform local targeting of interventions, and, when subsequent rounds of PLACE are implemented, can evaluate change in target populations.

Adolescent↗
PubMed2004

Monitoring sexual behaviour in general populations: a synthesis of lessons of the past decade.

This supplement contains selected papers from a workshop on the measurement of sexual behaviour in the era of HIV/AIDS held at the London School of Hygiene and Tropical Medicine in September 2003. The focus was on low and middle income countries, where the majority of HIV infections occur. The motive for holding such a meeting is easy to discern. As the AIDS pandemic continues to spread and as prevention programmes are scaling up, the need to monitor trends in sexual risk behaviours becomes ever more pressing. Behavioural data are an essential complement to biological evidence of changes in HIV prevalence or incidence. Biological evidence, though indispensable, is by itself insufficient for policy and programme guidance. AIDS control programmes need to be based on monitoring of not only trends in infections but also of trends in those behaviours that underlie epidemic curtailment or further spread.

Acquired Immunodeficiency Syndrome↗
PubMed2002

A pilot study of a rapid assessment method to identify places for AIDS prevention in Cape Town, South Africa.

A multidisciplinary approach appears promising for focusing interventions. The PLACE method (priorities for local AIDS control efforts) identifies where prevention programmes can access sexual networks containing individuals with high rates of new partner acquisition and provides information about whether sexually transmitted disease (STD) or AIDS prevention programmes are in place at those sites. The method provides useful information at relatively low cost, regardless of the phase of the HIV or STD epidemic. For example, in the growth phase of an epidemic, information on where people with high rates of new partner acquisition meet new sexual partners could be used to inform targeted surveillance or screening programmes to catch early cases.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Association between condom use and HIV infection: a randomised study of self reported condom use measures.

STUDY OBJECTIVE: To compare the association between different measures of condom use and prevalent HIV infection. DESIGN: Randomised cross sectional study to assess association between HIV infection and different measures of self reported condom use. Female sex workers were randomised to one of five different face to face questionnaires on condom use. Three questionnaires used always to never scales to measure use but differed in the reference period for use; a fourth asked about use in the last 10 coital acts; and the fifth was a retrospective log of coital acts in the past two weeks. Use was assessed with new clients, repeat clients, and non-clients. SETTING: Yaoundé and Douala, Cameroon. PARTICIPANTS: 2266 female sex workers. MAIN RESULTS: The association between condom use and prevalent HIV infection varied for different measures of condom use. None of the five level measures showed a dose response protective effect of condom use. Measures aimed at reducing recall bias (measures based on the past 10 coital acts or a coital log) showed little or no association with prevalent infection. Measures based on the past month or six months had a stronger association with prevalent infection. Regardless of the type of measure or reference period, the strongest association between use and infection was for use with partners who were not clients. CONCLUSION: These findings underscore challenges described by others of measuring condom use and interpreting the association between use and prevalent infection.

Adolescent↗
PubMed1998

A controlled trial of nonoxynol 9 film to reduce male-to-female transmission of sexually transmitted diseases.

BACKGROUND: Nonoxynol 9 is a proved spermicide, but whether it is also a microbicide is uncertain. A truly effective vaginal microbicide would reduce the susceptibility of women to sexually transmitted diseases, including infection with the human immunodeficiency virus (HIV). METHODS: We enrolled 1292 HIV-negative female sex workers in Cameroon and enrolled them in a double-blind, placebo-controlled study in which the participants were randomly assigned to use either a film containing 70 mg of nonoxynol 9 or a placebo film, inserted into the vagina before intercourse. All of the women were provided with latex condoms and were instructed to have their male sexual partners use them. At monthly follow-up visits, we examined the women with a colposcope for genital lesions, tested endocervical specimens for gonorrhea and chlamydia infection with DNA probes, tested for HIV infection, and treated the women for curable sexually transmitted diseases. RESULTS: The rates of HIV infection (cases per 100 woman-years) were 6.7 in the nonoxynol 9 group and 6.6 in the placebo group (rate ratio, 1.0; 95 percent confidence interval, 0.7 to 1.5). The rates of genital lesions were 42.2 cases per 100 woman-years in the nonoxynol 9 group and 33.5 in the placebo group (rate ratio, 1.3; 95 percent confidence interval, 1.0 to 1.6). The rates of gonorrhea were 33.3 and 31.1 cases per 100 woman-years in the nonoxynol 9 and placebo groups, respectively (rate ratio, 1.1; 95 percent confidence interval, 0.8 to 1.4). The corresponding rates of chlamydia infection in the nonoxynol 9 group and the placebo group were 20.6 and 22.2 per 100 woman-years (rate ratio, 0.9; 95 percent confidence interval, 0.7 to 1.3). The women reported that condoms were used during 90 percent of sexual acts. CONCLUSIONS: The use of a nonoxynol 9 vaginal film did not reduce the rate of new HIV, gonorrhea, or chlamydia infection in this group of sex workers who used condoms and received treatment for sexually transmitted diseases.

Adult↗
PubMed1998

Characteristics associated with prevalent HIV infection among a cohort of sex workers in Cameroon.

OBJECTIVE: To determine prevalence of HIV infection in a cohort of female sex workers in Cameroon, and to describe characteristics associated with HIV infection in this population. METHODS: In a cross sectional study, 2260 female sex workers in Cameroon were interviewed and screened for HIV serostatus. A standardised questionnaire was used to collect information on sociodemographic characteristics and sexual and health behaviours. RESULTS: Seropositive participants (18%) were more likely to be over age 25, have four or more children, live in Yaoundé or Douala for 5 years or less, solicit clients in their homes or on the street, have a low educational level, earn a weekly income of less than $24, and have no other occupation outside of sex work. A logistic regression model of selected sociodemographic characteristics indicated that women at particularly high odds of HIV infection were older, poorer, and new immigrants to their city of residence. CONCLUSION: This seroprevalence study found a lower HIV prevalence than had been previously reported. Although our results are different, this group is still at much higher risk of HIV infection than the population as a whole.

Adolescent↗
PubMed1998

Measuring condom use among sex workers in the Dominican Republic.

The purpose of this paper is to assess the internal consistency of self-reported condom use among sex workers in Puerto Plata and Santo Domingo, Dominican Republic. We examined the responses to questions about condom use among 4 cross-sectional samples of sex workers. We compared measures based on: (1) questions using always-to-never scales; (2) questions about use with the past 5 clients; and (3) questions about use in the past week obtained from a retrospective coital log. In each sample, more women reported 'always' using condoms with clients than with each of the past 5 clients. In 3 of the 4 samples, only about half of the women who reported 'always' using condoms used condoms with the most recent 5 clients and with all clients in the past week. Internal consistency was significantly higher when the comparison was limited to use with the most recent 5 clients and use in the past week. Self-reported measures of condom use can be difficult to interpret. Assessing the internal consistency of several measures of use provides insight into the strengths and weaknesses of each measure.

Condoms↗
PubMed1998

Prevalence and prediction of sexually transmitted diseases among sex workers in Cameroon.

The aim of the study was to determine the prevalence of sexually transmitted diseases (STDs), describe the frequency of genitourinary symptoms and signs, and to assess the accuracy of clinical diagnoses of STD in a cohort of Cameroonian sex workers. Physical examinations were conducted on 1233 sex workers in Yaoundé and Douala, Cameroon. Symptoms experienced within the 14 days prior to examination were collected. Women were tested for gonorrhoea, chlamydia infection, and trichomoniasis. Doctors' clinical impressions were compared with laboratory tests. Prevalence of cervical infection and trichomoniasis was 20%. A high percentage of abnormal signs and symptoms was found in this cohort. Clinical diagnosis for cervicitis and trichomoniasis had low sensitivities (<50%) while specificity remained high (>65%). In conclusion STDs are common among sex workers in Cameroon. Clinical diagnosis was not an accurate predictor of infection at the individual level in this population at risk of STD.

Adolescent↗
PubMed1998

Measuring condom use: asking "do you or don't you" isn't enough.

This article compares cross-sectional measures of condom use among 2,269 female sex workers in Cameroon randomly assigned to receive one of five different questionnaires measuring condom use. We found that the level of reported condom use varied depending on the type of survey questions used. Measures based on 2-week coital logs or the past 10 acts categorized more women as "100%" or "0%" users than always-to-never scales categorized women as "always" or "never" users. Consistency of use also varied by type of partner. Internal consistency of responses was high. Future studies should assess differences in prospective measures of condom use and the level of association between various measures and infection with sexually transmitted disease.

Adolescent↗
PubMed1997

Condom and nonoxynol-9 use and the incidence of HIV infection in serodiscordant couples in Zambia.

We aimed to measure the effectiveness of latex condoms and of nonoxynol-9 [N-9] spermicides, in preventing HIV transmission in heterosexual serodiscordant couples in Lusaka. Each couple was examined at clinic visits scheduled at 3-month intervals for one year or more per couple, or until seroconversion or discontinuation. Couples were given condoms and their choice of 3 N-9 products and advised to use both at every intercourse. Sexual exposure was ascertained from coital logs that recorded coitus and barrier method use. HIV serological testing was done at each clinic visit (ELISA and Western blot if positive). One hundred and ten discordant couples were followed for a mean of 17.6 months. Seventy-eight per cent of coital episodes were protected by condoms, 85% by spermicides and 6.4% were unprotected. Fourteen seroconversions occurred (8.7 infections per 100 couple-years [c-y]). The rate was higher among seronegative men than seronegative women. Among couples who reported using condoms at every intercourse the infection rate was 2.3/100 c-y, compared with 10.7/100 c-y among couples using condoms less consistently (rate ratio [RR] 0.2; 95% confidence interval [CI] 0-1.6). Among couples who reported using N-9 at every intercourse, the seroconversion rate was 6.9/100 c-y; among couples who reported less than full-time N-9 use, the rate was 8.9/100 c-y (RR 0.8; 95% CI 0.2-2.8). Among the subset of female seronegatives, the N-9 RR was 0.5 (95% CI 0.1-3.8). But when we calculated HIV rates according to N-9 consistency in coital acts when condoms were not used, there was no evidence of protection with higher N-9 use. Consistent use of latex condoms reduces the incidence of HIV infection, but the association between N-9 spermicides and HIV is less clear. The current study could not provide compelling data on the impact of N-9 spermicide use on risk of HIV infection. The study's small size, as well as the consistency of concurrent condom use, limited our inferences. Available spermicide products must be studied further.

Adolescent↗
PubMed1995

Fasting hyperinsulinemia and cardiovascular disease risk factors in nondiabetic adults: stronger associations in lean versus obese subjects. Atherosclerosis Risk in Communities Study Investigators.

The association between hyperinsulinemia and atherogenic risk factors has not been well studied in blacks and may be different for obese versus lean individuals. To investigate this possibility and to confirm the associations of hyperinsulinemia with cardiovascular disease risk factors in blacks and whites, we analyzed the joint associations of fasting serum insulin and obesity with risk factors in the Atherosclerosis Risk in Communities (ARIC) Study (1,293 black men, 4,797 white men, 2,033 black women, and 5,445 white women). Insulin values > or = 90th percentile (> or = 21 microU/mL) constituted hyperinsulinemia; body mass index (BMI) values > or = 27.3 kg/m2 for women and > or = 27.8 for men constituted obesity. Participants with hyperinsulinemia in all four race-sex groups had more atherogenic levels of most risk factors studied than those with normoinsulinemia. Among black men and women, mean levels of triglycerides, low-density lipoprotein cholesterol (LDL-C), apolipoprotein (apo) B, glucose, and fibrinogen (men only) were higher in hyperinsulinemic lean participants as compared with the normoinsulinemic obese group. Furthermore, most associations between insulin level and risk factors were stronger among lean versus obese subjects. For example, among lean black men, the difference in mean triglyceride concentration between those with hyperinsulinemia and those with normoinsulinemia was 147 - 99 = 48 mg/dL; among obese black men, the difference was 155 - 121 = 34 mg/dL (P < .05 for the interaction). Generally, similar negative interactions between BMI and insulin concentration were also observed among whites.(ABSTRACT TRUNCATED AT 250 WORDS)

Black People↗
PubMed1995

Nonoxynol-9 use, genital ulcers, and HIV infection in a cohort of sex workers.

OBJECTIVES: To measure the associations between use of nonoxynol-9 (N-9) and incidence of genital ulcers, and incident ulcers and HIV seroconversion. METHODS: In a study of barrier contraceptive use and HIV infection, 273 female sex workers used condoms and 100 mg N-9 suppositories, and recorded sexual activity on coital logs. Genital ulcers were diagnosed clinically at monthly clinic visits. HIV infection was diagnosed by ELISA and Western blot. We calculated ulcer incidence rates by level of N-9 use. A nested matched case-control analysis assessed the effect of ulcers on HIV acquisition. RESULTS: More frequent N-9 use was not associated with genital ulcers and may have been protective against the lesions. Ulceration was not a strong risk factor for HIV acquisition in this study (odds ratio 1.1; 95% confidence interval 0.3-3.5). CONCLUSIONS: Frequent use of N-9 can cause genital irritation and ulceration. Ulcers, in turn, may be risk factors for HIV acquisition. This study, however, did not find an association between N-9 use and ulcers, nor between ulcers and HIV. There is probably a threshold of N-9 use frequency or dose below which the risk of ulceration is minimal. Ulcers due to infectious causes may have been prevented by N-9 use in this cohort.

Adult↗
PubMed1995

The perceived social context of AIDS: study of inner-city sexually transmitted disease clinic patients.

The present study investigated perceptions of AIDS as a social problem relative to 10 other problems in a sample of 194 inner-city sexually transmitted disease (STD) clinic patients. Within-subjects analyses showed that AIDS was viewed as a more serious problem than housing, alcoholism, and child care, while AIDS was less of a problem than employment, drug abuse, crime, discrimination, and teen pregnancy, and no different from transportation and health care. Factor analysis was used to identify the interrelationships among social problems as perceived by STD patients. For men, factor analysis showed that AIDS was most closely related to crime, drug abuse, teen pregnancy, and discrimination, with these problems constituting the first factor and accounting for most of the variance in the analysis. Men also placed AIDS with alcoholism and child care on the third factor accounting for little variance. For women, however, AIDS clustered most closely with alcoholism and child care, accounting for a minimal amount of variance in the analysis. Results further showed that perceptions of social problems among women correlated with HIV-risk-related behaviors. The structural context of social problems, within which AIDS is embedded, is discussed with reference to HIV-AIDS-prevention interventions.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Gonorrhea as a risk factor for HIV acquisition.

OBJECTIVE: The role of gonorrhea in facilitating acquisition of HIV infection has only recently been studied. A previous nested case-control analysis in a cohort of female sex workers in Zaïre found a strong association between HIV seroconversion and prior gonorrheal infection. The objective of this study was to replicate the Zaïre study analysis in a cohort of 273 Cameroonian sex workers to determine whether gonorrhea increased the risk of HIV acquisition, and if the crude association between gonorrheal infection and HIV acquisition was weakened when the level of unprotected coitus was more carefully controlled. METHODS: We conducted a nested case-control study of initially HIV-1-negative women (n = 273) followed prospectively (with monthly sexually transmitted disease check-ups and 3-monthly HIV-1 serology). As in Zaïre, cases (seroconverters, n = 17) were compared with controls (women who remained HIV-1-negative, n = 68) for incidence of gonorrhea and sexual exposure during the presumed period of HIV-1 acquisition. RESULTS: The association between gonorrheal infection and subsequent HIV acquisition was stronger in Zaïre than in Cameroon [crude odds ratios (OR), 6.3 versus 2.2]. In both the Zaïre and Cameroon data the crude OR were reduced (6.3 to 4.8, and 2.2 to 1.7, respectively) by controlling for risk factors including a dichotomous variable indicating irregular or no condom use. When this variable was replaced in the Cameroon data with a more precise continuous variable indicating the percentage of unprotected coital acts, the gonorrhea OR was further reduced to 1.4 (95% confidence interval, 0.4-4.9). CONCLUSION: These results suggest that in the Cameroon cohort, gonorrheal infection did not facilitate HIV acquisition, but that having gonorrhea was a marker for unprotected coitus that facilitated HIV acquisition. The data demonstrate how OR can be overestimated when imprecise dichotomous measures of unprotected coitus are used. Future studies should plan for better control of self-reported condom use.

Adult↗