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Moore HA, Metcalf CA, Cassidy T, Hacking D, Shroufi A, Steele SJ, Duran LT, Ellman T. Investigating the addition of oral HIV self-tests among populations with high testing coverage - Do they add value? Lessons from a study in Khayelitsha, South Africa. PLoS One 2019; 14:e0215454. [PMID: 31048859 PMCID: PMC6497254 DOI: 10.1371/journal.pone.0215454] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 04/03/2019] [Indexed: 11/23/2022] Open
Abstract
Introduction HIV self-testing (HIVST) offers a useful addition to HIV testing services and enables individuals to test privately. Despite recommendations to the contrary, repeat HIV testing is frequent among people already on anti-retroviral treatment (ART) and there are concerns that oral self-testing might lead to false negative results. A study was conducted in Khayelitsha, South Africa, to assess feasibility and uptake of HIVST and linkage-to-care following HIVST. Methods Participants were recruited at two health facilities from 1 March 2016 to 31 March 2017. People under 18 years, or with self-reported previously-diagnosed HIV infection, were excluded. Participants received an OraQuick Rapid HIV-1/2 Antibody kit, and reported their HIVST results by pre-paid text message (SMS) or by returning to the facility. Those not reporting within 7 days were contacted by phone. Electronic and paper-based clinical and laboratory records were retrospectively examined for all participants to identify known HIV outcomes, after matching for name, date of birth, and sex. These findings were compared with self-reported HIVST results where available. Results Of 639 participants, 401 (62.8%) self-reported a negative HIVST result, 27 (4.2%) a positive result, and 211 (33.0%) did not report. The record search identified that of the 401 participants self-reporting a negative HIVST result, 19 (4.7%) were already known to be HIV positive; of the 27 self-reporting positive, 12 (44%) were known HIV positive. Overall, records showed 57/639 (8.9%) were HIV positive of whom 39/57 (68.4%) had previously-diagnosed infection and 18/57 (31.6%) newly-diagnosed infection. Of the 428 participants who self-reported a result, 366 (85.5%) reported by SMS. Conclusions HIVST can improve HIV testing uptake and linkage to care. SMS is acceptable for reporting HIVST results but negative self-reports by participants may be unreliable. Use of HIVST by individuals on ART is frequent despite recommendations to the contrary and its implications need further consideration.
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Affiliation(s)
- Hazel Ann Moore
- Médecins Sans Frontières, Khayelitsha Project, Cape Town, South Africa
- * E-mail:
| | - Carol A. Metcalf
- Médecins Sans Frontières, Khayelitsha Project, Cape Town, South Africa
| | - Tali Cassidy
- Médecins Sans Frontières, Khayelitsha Project, Cape Town, South Africa
- Division of Public Health Medicine, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
| | - Damian Hacking
- Médecins Sans Frontières, Khayelitsha Project, Cape Town, South Africa
| | - Amir Shroufi
- Médecins Sans Frontières, Cape Town, South Africa
| | | | | | - Tom Ellman
- Southern Africa Medical Unit, Médecins Sans Frontières, Cape Town, South Africa
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Rispel LC, Cloete A, Metcalf CA. 'We keep her status to ourselves': experiences of stigma and discrimination among HIV-discordant couples in South Africa, Tanzania and Ukraine. SAHARA J 2015; 12:10-7. [PMID: 25778765 PMCID: PMC4396513 DOI: 10.1080/17290376.2015.1014403] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In HIV-discordant relationships, the HIV-negative partner also carries the burden of a stigmatised disease. For this reason, couples often hide their HIV-discordant status from family, friends and community members. This perpetuates the silence around HIV-discordant relationships and impacts on targeted HIV prevention, treatment and counselling efforts. This article reports on experiences of stigma and discrimination among HIV-discordant couples in South Africa, Tanzania and Ukraine. During 2008, HIV-discordant couples who had been in a relationship for at least one year were recruited purposively through health-care providers and civil society organisations in the three countries. Participants completed a brief self-administered questionnaire, while semi-structured interviews were conducted with each partner separately and with both partners together. Interviews were analysed using thematic content analysis. Fifty-one couples were recruited: 26 from South Africa, 10 from Tanzania, and 15 from Ukraine. Although most participants had disclosed their HIV status to someone other than their partner, few were living openly with HIV discordance. Experiences of stigma were common and included being subjected to gossip, rumours and name-calling, and HIV-negative partners being labelled as HIV-positive. Perpetrators of discrimination included family members and health workers. Stigma and discrimination present unique and complex challenges to couples in HIV sero-discordant relationships in these three diverse countries. Addressing stigmatisation of HIV-discordant couples requires a holistic human rights approach and specific programme efforts to address discrimination in the health system.
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Affiliation(s)
- Laetitia C Rispel
- a PhD, is a professor at the Centre for Health Policy & Medical Research Council Health Policy Research Group, School of Public Health, Faculty of Health Sciences , University of the Witwatersrand , Johannesburg , South Africa
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Hoge EA, Lawson EA, Metcalf CA, Keshaviah A, Zak PJ, Pollack MH, Simon NM. Plasma oxytocin immunoreactive products and response to trust in patients with social anxiety disorder. Depress Anxiety 2012; 29:924-30. [PMID: 22807189 PMCID: PMC3751166 DOI: 10.1002/da.21973] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Revised: 05/11/2012] [Accepted: 06/02/2012] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Generalized Social Anxiety Disorder (GSAD) is characterized by excessive fear and avoidance of several types of social and performance situations. The pathophysiology is not well understood, but research in animals and humans has provided evidence that oxytocin helps regulate normal social affiliative behavior. Previous work in healthy male subjects demonstrated a rise in plasma oxytocin after receiving a high trust signal. To examine the oxytocin system in GSAD, we measured plasma oxytocin in GSAD patients and controls, before and after the social "Trust Game," a neuroeconomic test examining trust behavior and reaction to trust using real monetary incentives. METHODS Thirty-nine subjects with GSAD and 28 healthy controls provided three blood samples for oxytocin measurement before the Trust Game, and one sample after the game. Plasma estradiol was also measured at baseline. The Trust Game protocol version prioritized the sending of a signal of high cooperation and trust to all participants. All analyses controlled for gender and estradiol levels. RESULTS Mean oxytocin levels post-Trust Game (P = .025), and overall (area under the curve, P = .011) were lower in GSADpatients compared to controls, after controlling for sex and estradiol. There was no significant change in oxytocin levels after the game in either group. CONCLUSIONS We report low plasma oxytocin levels in patients with GSAD during a prosocial laboratory task paradigm. Additional research will be important to further examine the relationship between oxytocin and social behavior in GSAD.
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Affiliation(s)
- EA Hoge
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - EA Lawson
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - CA Metcalf
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - A Keshaviah
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - PJ Zak
- Center for Neuroeconomics Studies, Claremont Graduate University, Claremont, CA
| | - MH Pollack
- Department of Psychiatry, Rush University Medical Center, Chicago, IL
| | - NM Simon
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
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Rispel LC, Cloete A, Metcalf CA, Moody K, Caswell G. 'It [HIV] is part of the relationship': exploring communication among HIV-serodiscordant couples in South Africa and Tanzania. Cult Health Sex 2011; 14:257-268. [PMID: 22077668 DOI: 10.1080/13691058.2011.621448] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In many sub-Saharan African countries, a high proportion of people living with HIV are in long-term serodiscordant relationships. This paper explores how HIV serodiscordance shapes communication among couples in long-term HIV-serodiscordant relationships. A total of 36 couples were purposively recruited through healthcare providers and civil society organisations in South Africa (26) and Tanzania (10). We explored couples' portrayal of living in a serodiscordant relationship by conducting semi-structured interviews with each partner separately, followed by a joint interview with both partners. Using an adaptation of Persson's model on sero-silence and sero-sharing, we categorised coping style as 'sero-silent' if partners reported that they did not talk much with each other about issues related to their serodiscordant status or as 'sero-sharing' if they portrayed HIV as being an issue which they dealt with together. Some couples exhibited features of both coping styles and, at times, partners differed in their ways of coping.
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Affiliation(s)
- Laetitia C Rispel
- Centre for Health Policy & Medical Research Council Health Policy Research Group, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Rispel LC, Metcalf CA, Moody K, Cloete A, Caswell G. Sexual relations and childbearing decisions of HIV-discordant couples: an exploratory study in South Africa and Tanzania. Reprod Health Matters 2011; 19:184-93. [PMID: 21555099 DOI: 10.1016/s0968-8080(11)37552-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
This article reports on the influence of HIV on sexual relations and childbearing decisions of 36 HIV-discordant couples, 26 in South Africa and 10 in Tanzania, recruited into an exploratory study through hospital antiretroviral treatment clinics and civil society organisations working with people living with HIV. Self-administered questionnaires were used to obtain social and demographic information, while couples' sexual relations and childbearing decisions were explored through in-depth, semi-structured individual and couple interviews. The majority of the HIV-positive partners were women, who were on antiretroviral treatment. Almost one-third of South African respondents and half of those in Tanzania reported experiences of tension related to HIV-discordance, while more than half of the South Africans and almost three-quarters of the Tanzanians reported that intimacy had been affected by their discordant status. Those without children were more likely to desire children (17/23) than those who already had children (16/44), although this desire was influenced by fear of HIV transmission to the negative partner and medical professional advice. The study points to the need for targeted information for HIV discordant couples, as well as couple counselling and support services.
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Affiliation(s)
- Laetitia C Rispel
- Centre for Health Policy, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa.
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Abstract
Although the HIV epidemic among men who have sex with men (MSM) in South Africa preceded the onset of the generalised HIV epidemic by several years, current policies and programmes focus on heterosexual transmission and mother-to-child transmission. We used an adaptation of the UNAIDS Country Harmonised Alignment Tool (CHAT) to assess whether existing HIV policies and programmes in South Africa address the needs of MSM. This covered mapping of key risk factors and epidemiology of HIV among MSM; participation of MSM in the HIV response; and an enabling environment for service provision, funding and human resources. We found that current policies and programmes are unresponsive to the needs of MSM and that epidemiologic information is lacking, in spite of policy on MSM in the National Strategic Plan. We recommend that government initiate sentinel surveillance to determine HIV prevalence among MSM, social science research on the contexts of HIV transmission among MSM, and appropriate HIV prevention and care strategies. MSM should be closely involved in the design of policies and programmes. Supportive programme development should include dedicated financial and human resources, appropriate guidelines, and improved access to and coverage of HIV prevention, treatment and care services for MSM.
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Affiliation(s)
- Laetitia C Rispel
- Centre for Health Policy, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa.
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Rispel LC, Peltzer K, Phaswana-Mafuya N, Metcalf CA, Treger L. Assessing missed opportunities for the prevention of mother-to-child HIV transmission in an Eastern Cape local service area. S Afr Med J 2009; 99:174-179. [PMID: 19563095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023] Open
Abstract
BACKGROUND Prevention of new HIV infections is a critical imperative for South Africa; the prevention of mother-to-child transmission (PMTCT) is one of the most efficacious HIV prevention interventions. OBJECTIVE Assessment of a PMTCT programme to determine missed opportunities. SETTING The Kouga local service area (LSA), bordering Nelson Mandela Bay Municipality (Port Elizabeth) in the Eastern Cape. METHODS An assessment was conducted in 2007 before implementing technical support for strengthening the PMTCT programme, including: interviews with 20 PMTCT managers, 4 maternity staff and 27 other health workers on service provision, management, infrastructure, human resources and the health information system; 296 antenatal clinic users on their service perceptions; 70 HIV-positive women on HIV knowledge, infant feeding, coping, support and service perceptions; 8 representatives from community organisations and 101 traditional health practitioners (THPs). Observations were conducted during site visits to health facilities, and the District Health Information System (DHIS) data were reviewed. RESULTS Staff had high levels of awareness of HIV policies and most had received some relevant training. Nevirapine uptake varied by clinic, with an average of 56%. There were many missed opportunities for PMTCT, with 67% of pregnant women tested for HIV and only 43% of antenatal care attendees tested during a previous pregnancy. Only 6% of HIV-positive women reported support group participation. CONCLUSIONS Reducing missed opportunities for PMTCT requires strengthening of the formal health sector, intersectoral liaison, and greater community support. Priority areas that require strengthening in the formal health sector include HIV counselling and testing; family planning and nutrition counselling; infant follow-up; human resources; and monitoring and evaluation.
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Affiliation(s)
- L C Rispel
- Centre for Health Policy, School of Public Health, University of the Witwatersrand, Johannesburg.
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Peterman TA, Tian LH, Warner L, Satterwhite CL, Metcalf CA, Malotte KC, Paul SM, Douglas JM. Condom use in the year following a sexually transmitted disease clinic visit. Int J STD AIDS 2009; 20:9-13. [DOI: 10.1258/ijsa.2008.008177] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Consistent condom use can prevent sexually transmitted infections (STIs), but few studies have measured how the prevalence of consistent use changes over time. We measured the prevalence and correlates of consistent condom use over the course of a year. We did a secondary analysis of data from an HIV prevention trial in three sexually transmitted disease clinics. We assessed condom use during four three-month intervals for subjects and across their partnerships using unconditional logistic regression. Condom use was also assessed for subjects during all three-month intervals combined. The 2125 subjects reported on 5364 three-month intervals including 7249 partnership intervals. Condoms were always used by 24.1% of subjects and 33.2% of partnerships during a three-month interval. Over the year, 82% used condoms at least once but only 5.1% always used condoms. Always use of condom was more likely for subjects who had sex only once (66.5%) compared with >30 times (6.4%); one-time partnerships (64.1%) compared with main partnerships (22.2%); and in new partnerships (44.0%) compared with partnerships that were not new (24.5%). Although consistent condom use may prevent STIs, condoms were rarely used consistently during the year of follow-up.
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Affiliation(s)
| | | | - L Warner
- Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | | - C A Metcalf
- Human Sciences Research Council, Pretoria, South Africa
| | | | - S M Paul
- New Jersey Department of Health and Senior Services, Trenton, NJ, USA
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Peterman TA, Tian LH, Metcalf CA, Satterwhite CL, Malotte CK, DeAugustine N, Paul SM, Cross H, Rietmeijer CA, Douglas JM. High incidence of new sexually transmitted infections in the year following a sexually transmitted infection: a case for rescreening. Ann Intern Med 2006; 145:564-72. [PMID: 17043338 DOI: 10.7326/0003-4819-145-8-200610170-00005] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Studies show 11% to 15% of women treated for Chlamydia trachomatis are reinfected 3 to 4 months after treatment, suggesting the need for rescreening. There is little information on infections among men, infections with Neisseria gonorrhoeae or Trichomonas vaginalis, or long-term follow-up. OBJECTIVE To determine the incidence of new sexually transmitted infections during the year after a visit to a sexually transmitted disease (STD) clinic and associated risk factors. DESIGN Secondary analysis of data from a randomized, controlled trial (RESPECT-2). SETTING 3 urban STD clinics. PATIENTS Sexually active patients enrolled in an HIV prevention counseling trial. MEASUREMENTS Patient characteristics at the initial visit; behaviors during follow-up; and new infections with C. trachomatis, N. gonorrhoeae, or T. vaginalis (women only) detected during 4 scheduled return visits and any other interim visits. RESULTS 2419 persons had 8129 three-month follow-up intervals. Among 1236 women, 25.8% had 1 or more new infections (11.9% acquired C. trachomatis, 6.3% acquired N. gonorrhoeae, and 12.8% acquired T. vaginalis); among 1183 men, 14.7% had 1 or more new infections (9.4% acquired C. trachomatis, and 7.1% acquired N. gonorrhoeae). Black persons and those with sexually transmitted infections at baseline were at highest risk for recurrent infection (adjusted odds ratio, 2.5 and 2.4, respectively). For persons infected at baseline, the risk for infection was high at 3 and 6 months (16.3 per 100 three-month intervals) and remained high at 9 and 12 months (12.0 per 100 three-month intervals). Most (67.2%) infections were diagnosed during study-related visits, and 66.2% of these patients reported no symptoms. LIMITATIONS Because patients were recruited from STD clinics, results may not be generalizable. CONCLUSIONS Men and women who receive diagnoses of C. trachomatis, N. gonorrhoeae, or T. vaginalis infections should return in 3 months for rescreening because they are at high risk for new asymptomatic sexually transmitted infections. Although single-dose therapy may adequately treat the infection, it often does not adequately treat the patient.
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Affiliation(s)
- Thomas A Peterman
- Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
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Lesslie DP, Summy JM, Parikh NU, Fan F, Trevino JG, Sawyer TK, Metcalf CA, Shakespeare WC, Hicklin DJ, Ellis LM, Gallick GE. Vascular endothelial growth factor receptor-1 mediates migration of human colorectal carcinoma cells by activation of Src family kinases. Br J Cancer 2006; 94:1710-7. [PMID: 16685275 PMCID: PMC2361330 DOI: 10.1038/sj.bjc.6603143] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is the predominant pro-angiogenic cytokine in human malignancy, and its expression correlates with disease recurrence and poor outcomes in patients with colorectal cancer. Recently, expression of vascular endothelial growth factor receptors (VEGFRs) has been observed on tumours of epithelial origin, including those arising in the colon, but the molecular mechanisms governing potential VEGF-driven biologic functioning in these tumours are not well characterised. In this report, we investigated the role of Src family kinases (SFKs) in VEGF-mediated signalling in human colorectal carcinoma (CRC) cell lines. Vascular endothelial growth factor specifically activated SFKs in HT29 and KM12L4 CRC cell lines. Further, VEGF stimulation resulted in enhanced cellular migration, which was effectively blocked by pharmacologic inhibition of VEGFR-1 or Src kinase. Correspondingly, migration studies using siRNA clones with reduced Src expression confirmed the requirement for Src in VEGF-induced migration in these cells. Furthermore, VEGF treatment enhanced VEGFR-1/SFK complex formation and increased tyrosine phosphorylation of focal adhesion kinase, p130 cas and paxillin. Finally, we demonstrate that VEGF-induced migration is not due, at least in part, to VEGF acting as a mitogen. These results suggest that VEGFR-1 promotes migration of tumour cells through a Src-dependent pathway linked to activation of focal adhesion components that regulate this process.
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Affiliation(s)
- D P Lesslie
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, USA
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
| | - J M Summy
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
| | - N U Parikh
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
| | - F Fan
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
| | - J G Trevino
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, USA
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
| | - T K Sawyer
- Ariad Pharmaceuticals, Cambridge, MA, USA
| | | | | | | | - L M Ellis
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, USA
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
| | - G E Gallick
- Department of Cancer Biology, 1515 Holcombe Boulevard, Houston, TX, USA
- Department of Cancer Biology, Box #173, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030-4009, USA. E-mail:
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Sawyer TK, Shakespeare WC, Wang Y, Sundaramoorthi R, Huang WS, Metcalf CA, Thomas M, Lawrence BM, Rozamus L, Noehre J, Zhu X, Narula S, Bohacek RS, Weigele M, Dalgarno DC. Protein Phosphorylation and Signal Transduction Modulation: Chemistry Perspectives for Small-Molecule Drug Discovery. Med Chem 2005; 1:293-319. [PMID: 16787325 DOI: 10.2174/1573406053765486] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Protein phosphorylation has been exploited by Nature in profound ways to control various aspects of cell proliferation, differentiation, metabolism, survival, motility and gene transcription. Cellular signal transduction pathways involve protein kinases, protein phosphatases, and phosphoprotein-interacting domain (e.g., SH2, PTB, WW, FHA, 14-3-3) containing cellular proteins to provide multidimensional, dynamic and reversible regulation of many biological activities. Knowledge of cellular signal transduction pathways has led to the identification of promising therapeutic targets amongst these superfamilies of enzymes and adapter proteins which have been linked to various cancers as well as inflammatory, immune, metabolic and bone diseases. This review focuses on protein kinase, protein phosphatase and phosphoprotein-interacting cellular protein therapeutic targets with an emphasis on small-molecule drug discovery from a chemistry perspective. Noteworthy studies related to molecular genetics, signal transduction pathways, structural biology, and drug design for several of these therapeutic targets are highlighted. Some exemplary proof-of-concept lead compounds, clinical candidates and/or breakthrough medicines are further detailed to illustrate achievements as well as challenges in the generation, optimization and development of small-molecule inhibitors of protein kinases, protein phosphatases or phosphoprotein-interacting domain containing cellular proteins.
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Affiliation(s)
- T K Sawyer
- ARIAD Pharmaceuticals, Inc., 26 Landsdowne St., Cambridge, MA 01772, USA.
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Metcalf CA, Malotte CK, Douglas JM, Paul SM, Dillon BA, Cross H, Brookes LC, Deaugustine N, Lindsey CA, Byers RH, Peterman TA. Efficacy of a booster counseling session 6 months after HIV testing and counseling: a randomized, controlled trial (RESPECT-2). Sex Transm Dis 2005; 32:123-9. [PMID: 15668620 DOI: 10.1097/01.olq.0000151420.92624.c0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND HIV counseling prevents sexually transmitted diseases (STDs), with most of the benefit accumulating in the first 6 months. STUDY The authors conducted a multicenter, randomized, controlled trial of a 20-minute additional (booster) counseling session 6 months after HIV counseling compared with no additional counseling for prevention of STDs (gonorrhea, chlamydia, trichomoniasis). Participants were 15- to 39-year-old STD clinic patients in Denver, Long Beach, and Newark. RESULTS Booster counseling was completed by 1120 (67.8%) of 1653 assigned to receive it. An incident STD during the 6 to 12 months after initial counseling (and within the 6 months after scheduled booster counseling) was detected in 141 of 1653 (8.5%) participants in the booster counseling group and 144 of 1644 (8.8%) in the no-booster group (relative risk, 0.97; 95% confidence interval, 0.78-1.22). Three months after booster counseling, sexual risk behaviors were reported less frequently by the booster group than the no-booster group. CONCLUSIONS Booster counseling 6 months after HIV testing and counseling reduced reported sexual risk behavior but did not prevent STDs.
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Affiliation(s)
- Carol A Metcalf
- Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
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Metcalf CA, Douglas JM, Malotte CK, Cross H, Dillon BA, Paul SM, Padilla SM, Brookes LC, Lindsey CA, Byers RH, Peterman TA. Relative Efficacy of Prevention Counseling With Rapid and Standard HIV Testing: A Randomized, Controlled Trial (RESPECT-2). Sex Transm Dis 2005; 32:130-8. [PMID: 15668621 DOI: 10.1097/01.olq.0000151421.97004.c0] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Two risk-reduction counseling sessions can prevent sexually transmitted diseases (STDs); however, return rates for test results are low. STUDY A randomized, controlled trial compared rapid HIV testing and counseling in 1 visit with standard HIV testing and counseling in 2 visits. Main outcomes were STDs (gonorrhea, chlamydia, trichomoniasis, syphilis, HIV) within 12 months. Participants were 15- to 39-year-old STD clinic patients in Denver, Long Beach, and Newark. STD screening and questionnaires were administered every 3 months. RESULTS Counseling was completed by 1632 of 1648 (99.0%) of the rapid-test group and 1144 of 1649 (69.4%) of the standard-test group. By 12 months, STD was acquired by 19.1% of the rapid group and 17.1% of the standard group (relative risk [RR], 1.11; confidence interval [CI], 0.96-1.29). STD incidence was higher in the rapid-test group than in the standard-test group among men (RR, 1.34; CI, 1.06-1.70), men who had sex with men (RR, 1.86; 95% CI, 0.92-3.76), and persons with no STDs at enrollment (RR, 1.21; 95% CI, 0.99-1.48). Behavior was similar in both groups. CONCLUSIONS Counseling with either test had similar effects on STD incidence. For some persons, counseling with standard testing may be more effective than counseling with rapid testing.
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Affiliation(s)
- Carol A Metcalf
- Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
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14
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Bohacek RS, Dalgarno DC, Hatada M, Jacobsen VA, Lynch BA, Macek KJ, Merry T, Metcalf CA, Narula SS, Sawyer TK, Shakespeare WC, Violette SM, Weigele M. X-Ray structure of citrate bound to Src SH2 leads to a high-affinity, bone-targeted Src SH2 inhibitor. J Med Chem 2001; 44:660-3. [PMID: 11262076 DOI: 10.1021/jm0002681] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R S Bohacek
- ARIAD Pharmaceuticals, Inc., 26 Landsdowne Street, Cambridge, Massachusetts 02139-4234, USA.
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Dalgarno DC, Metcalf CA, Shakespeare WC, Sawyer TK. Signal transduction drug discovery: targets, mechanisms and structure-based design. Curr Opin Drug Discov Devel 2000; 3:549-564. [PMID: 19649883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Signal transduction targets include catalytic and/or non-catalytic domains, which are critical to various aspects of cell growth, differentiation, metabolism and function, mitogenesis, motility and gene transcription. Specific examples of molecular targets include the catalytic domains of protein tyrosine kinases (PTKs) and of protein tyrosine phosphatases (PTPases), as well as related protein-protein interaction motifs (eg, SH2, PTB and SH3 domains). From the relationship of tyrosine phosphorylation to intracellular pathway regulation by PTKs and PTPases, the dynamic and reversible binding interactions of SH2 and PTB domain-containing proteins with their cognate phosphotyrosine (pTyr)-containing proteins, provide an additional dimension to the modulation of signal transduction pathways which exist as a result of pTyr formation, degradation and molecular recognition events. This review focuses on our current understanding of key relative to recent reports which have provided further insight into their three-dimensional structure and mechanism. This review also highlights recent progress in the design and optimization of molecular mechanism-based signal transduction inhibitors.
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Affiliation(s)
- D C Dalgarno
- ARIAD Pharmaceuticals Inc, Cambridge, MA 02139, USA.
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Metcalf CA, Eyermann CJ, Bohacek RS, Haraldson CA, Varkhedkar VM, Lynch BA, Bartlett C, Violette SM, Sawyer TK. Structure-based design and solid-phase parallel synthesis of phosphorylated nonpeptides to explore hydrophobic binding at the Src SH2 domain. J Comb Chem 2000; 2:305-13. [PMID: 10891096 DOI: 10.1021/cc990074a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Using a novel, solid-phase parallel synthetic route and a computational docking program, a series of phosphorylated nonpeptides were generated to determine their structure-activity relationships (SAR) for binding at the SH2 domain of pp60src (Src). A functionalized benzoic acid intermediate was attached to solid support via Rink amide linkage, which upon acid cleavage generated the desired benzamide template-based nonpeptides in a facile manner. Compounds were synthesized using a combination of solid- and solution-phase techniques. Purification using reversed-phase, semipreparative HPLC allowed for quantitative SAR studies. Specifically, this work focused on functional group modifications, in a parallel fashion, designed to explore hydrophobic binding at the pY+3 pocket of the Src SH2 domain.
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Affiliation(s)
- C A Metcalf
- ARIAD Pharmaceuticals, Inc., 26 Landsdowne Street, Cambridge, Massachusetts 02139-4234, USA.
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Metcalf CA, Hoffman MN, Steyn K, Katzenellenbogen JM, Fourie JM. Design and baseline characteristics of a hypertension intervention program in a South African village. J Hum Hypertens 1996; 10:21-6. [PMID: 8642186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The Mamre Hypertension Project was initiated in response to studies indicating that hypertension and cardiovascular disease were prevalent in a rural community of Mamre, located in the Western Cape, South Africa. A survey was done to collect baseline information on the prevalence of hypertension and other cardiovascular disease risk factors. The age-adjusted prevalence of hypertension in people aged 15 years or more was 13.9% in men and 16.3% in women. Of the hypertensive subjects, 27% were not aware of their hypertension, a further 14.4% were not on treatment, and only 16.8% had their blood pressure (BP) controlled at under 140/90 mm Hg. There was a high prevalence of smoking, heavy alcohol use (in men), obesity (in women) and physical inactivity. The survey results will be used to assess the impact of the intervention programme using a before and after design, and are being used to direct interventions. The intervention programme comprises a BP station catering primarily for people with hypertension, and a health education and promotion programme directed at the general community. The BP station screens for hypertension, monitors BP and compliance with medication in hypertensives, and encourages risk factor modification. Health promotion activities include a smoking cessation group and a weight reduction and exercise group. These are run by community volunteers with support from outside consultants. The effects of the programme will be assessed after 4-5 years.
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Affiliation(s)
- C A Metcalf
- Centre for Epidemiological Research in Southern Africa, Medical Research Council, Parowvallei, South Africa
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Metcalf CA, Yach D, de Beer ZJ. Missed opportunities for immunisation at hospitals in the western Cape--a reappraisal. S Afr Med J 1994; 84:149-52. [PMID: 7740351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Immunisation practices were examined at 6 hospitals in the western Cape during the latter half of 1992 to determine whether these practices had improved subsequent to the February 1991 resolution of the Health Matters Committee (HMC) on immunisation in hospitals, and since a similar study was undertaken in 1990. Exit interviews were conducted with the escorts of all children aged 3-59 months who attended the study hospitals on the days designated for the study. In the second study, 88 of the 311 children studied (28.3%) were in need of immunisation on arrival, but only 12 of the 88 (13.6%) were immunised during the hospital visit. There was no evidence of an increase in requests to see children's Road-to-Health cards (37.1% compared with 35.2% previously). The incidence of missed opportunities for measles immunisation in children aged 6-59 months remained unacceptably high (51.4% compared with 63.7% previously, when a strict definition was used; and 15.7% compared with 18.1% previously, when a lenient definition was used). Health authorities at all levels need to take urgent action to address the problem of missed opportunities for immunisation at hospitals.
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Affiliation(s)
- C A Metcalf
- Centre for Epidemiological Research in Southern Africa, South African Medical Research Council, Parowvallei, CP
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Volmink JA, Metcalf CA, Zwarenstein M, Heath S, Laubscher JA. Attitudes of private general practitioners towards health care in South Africa. S Afr Med J 1993; 83:827-33. [PMID: 7839213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The need for health care reform in South Africa is acknowledged by the government as well as by the non-governmental health sector. There is, however, no unanimity regarding the nature of the envisaged reform. A country-wide postal survey of 700 private sector general practitioners (GPs) from a commercial database of 5,000 was conducted to explore attitudes towards health care. A response rate of 67.4% was obtained. Respondents were mostly male (92%) and urban-based (64%). The median age was 42 years. Most respondents: (i) believed health care to be a right for all citizens; (ii) favoured private or a combination of private and public funding mechanisms with fee-for-service arrangements; (iii) opposed cost-containment measures imposed by funders, e.g. medical aids; and (iv) believed doctors should be responsible for primary care in under-served areas. After sex, age, location (urban versus rural) and GP postgraduate qualification had been controlled for by means of logistic regression techniques, the university at which a respondent's basic degree was obtained emerged as the only independent predictor of attitudes to the following: (i) comprehensive care as a right; (ii) integration of the public and private sectors; (iii) preferred funding source for a future health system; and (iv) preference for fee-for-service remuneration. Both university and gender independently predicted attitudes on GPs' income. Graduates of white, Afrikaans-medium universities were strongly in favour of a privately funded and fee-for-service orientated system. Those who qualified at black universities, on the other hand, favoured public funding with less emphasison fee-for-service.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J A Volmink
- Centre for Epidemiological Research in Southern Africa (CERSA), Medical Research Council, Parowvallei, CP
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Metcalf CA, Yach D. Smoking policies in the workplace in the western Cape. S Afr Med J 1992; 81:23-6. [PMID: 1729730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A postal survey of workplace smoking restrictions among the member organisations of the Cape Chamber of Industries was carried out in 1989. The response rate was 57.1%. Of the 572 respondent organisations, 66.1% had some smoking restrictions. Large workplaces were more likely to restrict smoking than small workplaces: 42.0% of those with fewer than 10 employees had restrictions, increasing to 90.9% of those with more than 500 employees. Organisations producing manufactured goods (other than engineering) were more likely to have restrictions than non-manufacturing concerns. Smoking was commonly restricted on the factory floor (61.3%) and in warehouses (55.8%), but only 7.4% prohibited smoking in shared offices. The reasons for smoking restrictions stated most frequently were the fire hazard (85.3%) and legislation (66.0%). Only 29.1% stated that health care concerns were an important reason for restrictions, while a further 16.3% stated that health was a minor reason for restrictions. Of the respondents, 48.4% expressed a need for guidance in improving their smoking policies. These results indicate that there is considerable potential for intervention to decrease both active and passive smoking in local workplace settings.
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Affiliation(s)
- C A Metcalf
- Centre for Epidemiological Research, South African Medical Research Council, Parowvallei
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Abstract
'Puppets Against AIDS' is a novel educational medium being used to try to reduce the spread of HIV infection in South Africa. It involves the use of street theatre employing two-metre-high puppets who act out a story of how one person, who is infected with HIV, passes it onto a series of other people until he eventually dies. The puppet show was evaluated in two phases. The first involved a content analysis of a video recording of the show by a multidisciplinary group, according to a set of criteria for appropriate education on HIV infection. This show was found to be professional and comprehensive in terms of the educational messages provided. Some suggestions were made for improvements. The second phase was a before and after study of the impact on the audience at a series of live shows. The show made a significant contribution to knowledge and intended behaviour in the short term. Overall it was felt that the show does make a valuable contribution, but could be made more effective if incorporated into existing community-based education programmes on HIV infection.
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Affiliation(s)
- D Skinner
- Centre for Epidemiological Research in Southern Africa, Tygerberg
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van der Merwe S, Yach D, Metcalf CA. Peering into the black hole--the quality of black mortality data in Port Elizabeth and the rest of South Africa. S Afr Med J 1991; 79:419-22. [PMID: 2020878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In the year ending 30 June 1989, 26.8% of 5,345 deaths in the Port Elizabeth area were classified as ill-defined. A study was undertaken in an attempt to identify the reasons for the high proportion of such deaths. Copies of all death notifications and death register forms of black people in the area served by the Port Elizabeth City Health Department were collected for a 6-week period. Of the 316 deaths, 154 (48.7%) were certified by medical practitioners at a hospital, 158 (50%) by the police and 4 (1.3%) by private medical practitioners. Of the police-certified deaths 116 (73.4%) were recorded as due to 'natural causes', with the remainder being submitted to autopsy. Of the hospital deaths, 26% were not adequately described in the section for the cause of death on the death certificate. Review of national mortality data for 1985 showed that only 29.9% of ill-defined deaths (in all population groups) were certified by a medical practitioner. The prime source of deaths classified as ill-defined, both in Port Elizabeth and nationally, were those not certified by a medical practitioner. Strategies aimed at minimising the number of deaths certified by the police need to be developed.
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Mathews C, Kuhn L, Metcalf CA, Joubert G, Cameron NA. Knowledge, attitudes and beliefs about AIDS in township school students in Cape Town. S Afr Med J 1990; 78:511-6. [PMID: 2237683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Students (N = 377) from four Cape Town township high schools were surveyed to obtain information on their knowledge of and attitudes towards the acquired immunodeficiency syndrome (AIDS), and on their sexual behaviour. The study was undertaken to provide information for planning an AIDS education intervention. Three-quarters of students reported that they had had sexual intercourse. Most students had heard of AIDS, and the majority of these knew that it was infectious. More than half of the students were confused or lacked knowledge about the modes of transmission. Two-thirds of the students believed AIDS could be prevented, but knowledge of prevention strategies was superficial. Of the sexually active students only 11.4% had ever used a condom, and of all students 39.6% stated that they would use a condom in the future. Two-thirds of the students were not aware that there is no cure for AIDS. Students did not acknowledge that AIDS could affect them directly, and attributed the problem to prostitutes and 'promiscuous' people in 36.4% of responses, and to 'white' people in 23.8% of responses. Students expressed intolerance, fear and rejection of people with AIDS, and only 6.4% would accept an affected person into their class. Almost all the students wanted AIDS education at school, and most of these requested that the school nurse facilitate this education. It is concluded that appropriate AIDS prevention education is urgently required for both high school and junior school students.
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Affiliation(s)
- C Mathews
- Centre for Epidemiological Research in South African Medical Research Council, Parowvallei, CP
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Metcalf CA, Bradshaw D, Stindt WW. Knowledge and beliefs about tuberculosis among non-working women in Ravensmead, Cape Town. S Afr Med J 1990; 77:408-11. [PMID: 2330526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The results of a community-based survey on knowledge and beliefs about tuberculosis in non-working women are presented. The women in the sample showed a very good knowledge of the important aspects of tuberculosis: 90% were aware that it is a problem in their area; 97% knew that it affects the chest; 94% said that it could be fatal; 85% considered it to be infectious and 88% knew that the local clinic provided treatment. Their knowledge of symptoms was good overall but the study revealed misconceptions about the causes and transmission of tuberculosis; 16% indicated that they would not be keen to associate with people with tuberculosis owing to fear of infection. The design effect of cluster sampling was considered in the analysis. The highest design effects (i.e. the most clustering of responses) were found for responses to questions on the causes of tuberculosis and places where treatment could be obtained, possibly reflecting that these beliefs are influenced by neighbourhood contacts. Future tuberculosis education in this group needs to build on existing knowledge and awareness and should focus on changing attitudes such as misconceptions about transmission and the stigmatisation of the disease. Health workers face the challenge of changing behaviour in this community to ensure that people with symptoms present early for screening and that people diagnosed as having tuberculosis comply with treatment.
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Affiliation(s)
- C A Metcalf
- (CERSA) of the South African Medical Research Council, Parowvallei, CP
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