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Biomedical subjects

Catherine M Lowndes

Publications and source records attributed to Catherine M Lowndes.

15 recordsLinked to original sources
PubMed2005

Comparison of HIV-specific CD8 T-cell responses among uninfected individuals exposed to HIV parenterally and mucosally.

OBJECTIVE: To assess the influence of route of HIV exposure on the development of HIV-specific CD8 T-cell responses in exposed, uninfected (EU) individuals. DESIGN: Two groups of EU exposed to virus through either sexual or intravenous contact were studied. Group I included subjects (n = 20) who had unprotected sexual contact with known HIV-infected partners and no intravenous HIV exposure; Group II included individuals (n = 27) who had shared needles with HIV-infected partners and had no sexual exposure to this virus. Between-group comparisons were made for the proportion of responders, breadth, magnitude, and specificity of HIV-specific responses. METHODS: : The interferon-gamma ELISPOT assay was used to detect HIV-specific effector activity. Peripheral blood mononuclear cells (PBMC) from each subject were stimulated with a panel of HIV peptides restricted to the MHC class I alleles expressed by the individual. RESULTS: A similar proportion of EU tested from each group (35.0% Group I versus 22.2% Group II) recognized at least one HIV peptide. Group I and II subjects recognized HIV peptides with a similar cumulative intensity of 130 +/- 67.5 and 182.9 +/- 184.2 spot forming cells/1 x 10 PBMC, respectively, and similar magnitude per stimulatory peptide of 82.7 and 78.4 SFC/1 x 10 PBMC, respectively. The proportion of stimulatory peptides derived from HIV Gag, reverse transcriptase, Env, and Nef was not significantly different between the two EU groups. HLA-A*0201 restricted HIV epitopes immunodominant in infected individuals are rarely stimulatory in EU subjects. CONCLUSIONS: Both mucosal and parenteral exposure to HIV can elicit HIV-specific CD8 T-cell responses with similar characteristics.

Adult↗
PubMed2005

Divergent approaches to partner notification for sexually transmitted infections across the European union.

OBJECTIVE: The objective of this study was to characterize partner notification (PN) policy and practice for sexually transmitted infections (STIs) in the European Union (EU) and Norway. GOAL: The goal of this study was to promote European good practice in PN. STUDY: This study consisted of a cross-sectional survey using a structured questionnaire to national STI surveillance leads. RESULTS: Considerable heterogeneity exists in approaches to PN. In 2 countries, PN is compulsory for notifiable STIs; and in 13, it is voluntary. Most countries use patient referral but 5 of 15 also offer provider referral. Activity level varies by country and disease. Etiologic treatment of contacts is most common; 5 usually offer epidemiologic treatment and patient-expedited treatment is unusual. Similarities exist with provision mainly by specialized STI treatment services for bacterial STIs. CONCLUSIONS: This divergence in approach calls for the setting of minimum standards for PN delivery together with mechanisms for establishing and sharing best practice. Further research must identify monitoring systems for inclusion in routine surveillance.

Contact Tracing↗
PubMed2005

Impact of gender and sex work on sexual and injecting risk behaviors and their association with HIV positivity among injecting drug users in an HIV epidemic in Togliatti City, Russian Federation.

OBJECTIVES: Togliatti City is witness to a large epidemic of human immunodeficiency virus (HIV) associated with injecting drug use (IDU). GOAL: This study sought to examine whether risk behaviors and risk factors associated with HIV differed across a sample IDUs by gender and sex work. STUDY: A sample of IDU (n = 423) comprising female sex workers (SWs) (n = 66), non-sex workers (nonSWs) (n = 89) and men (n = 268) were recruited by field workers in community settings. Behavioral and HIV prevalence data were collected. RESULTS: HIV prevalence did not differ across the groups ( approximately 56%), but gender adversely affected some risk factors. A comparison of risk behaviors indicated that SWs were more likely to engage in risky injecting behaviors than either men or nonSWs. They were also more likely to report a history of sexually transmitted infections. CONCLUSIONS: IDUs involved in sex work and IDU nonSWs require specific and targeted interventions to facilitate safer injecting and sexual behaviors.

Adolescent↗
PubMed2005

Incorrect condom use and frequent breakage among female sex workers and their clients.

Our objective was to assess if female sex workers (FSWs) and their potential male clients in Cotonou, Benin, know how to use male condoms correctly. From April to June 2000, 314 FSWs and 208 men were interviewed, and asked to demonstrate on a wooden penis how they usually use male condoms. In all, 27.6% of both women and men tore the condom envelope on the notch; 89.3% of the women versus 75.4% of the men easily found the correct side; 17.3% of the women versus 28.3% of the men held the top of the condom to avoid air entering; 91.4% of the women versus 75.6% of the men correctly unrolled the condom. Taking all the four criteria together, only approximately 11% of participants performed a correct condom use demonstration. FSWs frequently reported condom breakage, which was significantly associated with incorrect condom demonstration (P = 0.04). Correct condom use is suboptimal in these heavy consumers of male condoms in Benin. Condom breakage is frequent and is associated with incorrect use.

Africa South of the Sahara↗
PubMed2004

Injecting equipment sharing among injecting drug users in Togliatti City, Russian Federation: maximizing the protective effects of syringe distribution.

OBJECTIVE: To compare risk factors for injecting equipment sharing among injecting drug users (IDUs) in Togliatti City, Russia. DESIGN: Unlinked, anonymous, cross-sectional community-recruited survey with oral fluid sample collection. METHODS: Between September and October 2001, 426 IDUs completed an interviewer-administered questionnaire and oral fluid samples were tested for HIV. Univariate and multivariate analyses compared potential risk factors for injecting equipment sharing. RESULTS: More than half (56% [234/418]) of the sample were positive for antibodies to HIV. A third (36%) had injected with used needles and syringes in the last 4 weeks. IDUs who reported syringe exchanges or outreach workers as their main sources of new needles and syringes in the last 4 weeks had 0.3 times the odds of sharing compared with those obtaining them from a pharmacy or shop, whereas those whose main source was buying them from the streets or obtaining them from friends, sexual partners, or other drug users had 12 times the odds of receptive needle and syringe sharing. IDUs who reported being last arrested or detained by the police for a drug-related offense had higher odds of sharing. CONCLUSIONS: Findings highlight the delicate balance in HIV prevention between potentially competing strategies of law enforcement and syringe distribution.

Analysis of Variance↗
PubMed2003

Situational factors influencing drug injecting, risk reduction and syringe exchange in Togliatti City, Russian Federation: a qualitative study of micro risk environment.

We undertook a qualitative study to explore the micro-environment of drug injecting, risk reduction and syringe exchange practices among injecting drug users (IDUs) in Togliatti City, Russia. Semi-structured qualitative interviews (n=57) were undertaken with current IDUs in May 2001. Findings highlight a recent transition away from hanka (a home-produced liquid opiate derived from opium poppy) towards the injection of heroin powder, and a drug use culture in which injecting predominates. Findings emphasise that risk reduction practices may be influenced less by availability of injecting equipment than by an interplay of situational and micro-environmental factors. Principal among these is a reported fear of police detainment or arrest among IDUs which encourages a reluctance to carry needles and syringes, and which in turn, is associated with needle and syringe sharing at the point of drug sale. We note the role of policing practices in influencing risk reduction and the potential role of policing agencies in supporting HIV prevention initiatives among IDUs.

Adolescent↗
PubMed2002

Decline in the prevalence of HIV and sexually transmitted diseases among female sex workers in Cotonou, Benin, 1993-1999.

BACKGROUND: Within an ongoing HIV/STD prevention project aimed at female sex workers (FSW) in Cotonou, Benin, we evaluated time trends in HIV and STD prevalences from 1993 to 1999. DESIGN: Three serial cross-sectional surveys were conducted in 1993 (n = 374), 1995-1996 (n = 365), and 1998-1999 (n = 591). A questionnaire was administered to the FSW and they were screened for HIV, syphilis, Neisseria gonorrhoeae, and Chlamydia trachomatis. RESULTS: The mean percentage of condom use with clients in the week preceding the interview increased from 62.2% in 1993 to 80.7% in 1998-1999 (P = 0.0001). The prevalence of all infections decreased significantly (all P < 0.02; chi-square for trend) over time: HIV from 53.3% in 1993 to 40.6% in 1998-1999; syphilis from 8.9 to 1.5%; gonorrhoea from 43.2 to 20.5%; and chlamydia from 9.4 to 5.1%. However, the mean age of FSW decreased from 31.0 to 28.4 years between 1993 and 1998-1999. Moreover, the country of origin of these women changed dramatically over time: the proportion of Ghanaian women decreased from 66.3% in 1993 to 21.6% in 1998-1999 when the predominant group became Nigerian (38.0%). When controlling for age and country of origin, HIV prevalence was stable over time (P = 0.71), whereas the downward trend remained significant for syphilis and gonorrhoea (both P < 0.001), and was present but not significant for chlamydia (P = 0.13). CONCLUSION: These data suggest that the time trends in HIV and STD prevalences are partly due to the changing sex work milieu, but that the intervention also had an impact. Prevention programmes aimed at FSW should be highly prioritized.

Adult↗
PubMed2002

Syndromic versus laboratory-based diagnosis of cervical infections among female sex workers in Benin: implications of nonattendance for return visits.

BACKGROUND: The syndromic diagnostic approach is the most realistic and cost-effective strategy for controlling sexually transmitted infections (STIs) in the developing world. Its potential advantages should be evaluated. GOAL: The goal of the current study was to examine whether the syndromic approach might diagnose more cases of cervicitis due to Neisseria gonorrhoeae or Chlamydia trachomatis than laboratory tests. STUDY DESIGN: The participants were 481 female sex workers in Benin, screened for STIs and treated on the basis of the clinical findings. They were asked to return to the clinic within 10 days for laboratory test results and appropriate treatment when necessary. RESULTS: The prevalence of cervical infections was 24.5%. In comparison to the gold standard, the sensitivity of the syndromic diagnosis approach for the detection of N gonorrhoeae/C trachomatis infections was 48.3%; that of the locally performed laboratory tests was 74.6%. However, the sensitivity of the laboratory tests dropped to 28.8% when it was taken into consideration that 57.6% of the infected women did not return to the clinic within 10 days. CONCLUSIONS: The syndromic diagnosis approach should continue to be used for female sex workers in Benin because returning for treatment is problematic. Presumptive treatment at their initial visit could be a complement to this approach, given the high prevalence of cervicitis in this population.

Adult↗
PubMed2002

Diagnostic detection of human immunodeficiency virus type 1 antibodies in urine: a brazilian study.

We evaluated, for the first time in Latin America, the performance of a commercial enzyme immunoassay (EIA) (Calypte Biomedical Corporation, Berkeley, Calif.) that detects human immunodeficiency virus type 1 (HIV-1)-specific antibodies in urine in comparison to standard serological assays (two commercial EIAs and a commercial Western blot [WB] assay). Paired serum and urine specimens were collected from two different groups of Brazilian patients: 225 drug users with unknown HIV status who attended drug treatment centers in Rio de Janeiro, Brazil, and 135 subjects with known HIV status. Patients showing positive results in the serum EIAs and/or in the urine EIA were serologically confirmed by WB assay. For 135 individuals with known HIV status, the urine EIA showed 100% sensitivity (74 positive samples) and 95.1% specificity (58 of 61 negative specimens). For 225 drug users, the test showed 100% sensitivity (2 positive samples) and 98.7% specificity (220 of 223 negative samples) compared to WB-confirmed serological EIA results. Thus, in a total of 360 samples, the urine EIA correctly identified all 76 HIV-positive samples and 278 of 284 negative samples (100% sensitivity and 97.9% specificity). Detailed analysis of the urine EIA results indicates that an increase of the recommended cutoff value might raise the specificity of the assay without affecting its sensitivity. Our results suggest that the HIV-1 urine EIA is a good screening test suitable for developing countries like Brazil. However, as for all other HIV screening tests on the market, it is not specific enough to be used as a one-step test and therefore requires confirmation.

AIDS Serodiagnosis↗