Effectiveness of latex condoms as a barrier to human immunodeficiency virus-sized particles under conditions of simulated use

HIV infection

The AIDS epidemic has been a global public health issue for more than 40 years and has resulted in ~40 million deaths. AIDS is caused by the retrovirus, HIV-1, which is transmitted via body fluids and secretions. After infection, the virus invades host cells by attaching to CD4 receptors and thereafter one of two major chemokine coreceptors, CCR5 or CXCR4, destroying the host cell, most often a T lymphocyte, as it replicates. If unchecked this can lead to an immune-deficient state and demise over a period of ~2-10 years. The discovery and global roll-out of rapid diagnostics and effective antiretroviral therapy led to a large reduction in mortality and morbidity and to an expanding group of individuals requiring lifelong viral suppressive therapy. Viral suppression eliminates sexual transmission of the virus and greatly improves health outcomes. HIV infection, although still stigmatized, is now a chronic and manageable condition. Ultimate epidemic control will require prevention and treatment to be made available, affordable and accessible for all. Furthermore, the focus should be heavily oriented towards long-term well-being, care for multimorbidity and good quality of life. Intense research efforts continue for therapeutic and/or preventive vaccines, novel immunotherapies and a cure.

Recent progress in advanced biomaterials for long-acting reversible contraception

Unintended pregnancy is a global issue with serious ramifications for women, their families, and society, including abortion, infertility, and maternal death. Although existing contraceptive strategies have been widely used in people's lives, there have not been satisfactory feedbacks due to low contraceptive efficacy and related side effects (e.g., decreased sexuality, menstrual cycle disorder, and even lifelong infertility). In recent years, biomaterials-based long-acting reversible contraception has received increasing attention from the viewpoint of fundamental research and practical applications mainly owing to improved delivery routes and controlled drug delivery. This review summarizes recent progress in advanced biomaterials for long-acting reversible contraception via various delivery routes, including subcutaneous implant, transdermal patch, oral administration, vaginal ring, intrauterine device, fallopian tube occlusion, vas deferens contraception, and Intravenous administration. In addition, biomaterials, especially nanomaterials, still need to be improved and prospects for the future in contraception are mentioned.

Prevalence of Consistent Condom Use and Associated Factors among Serodiscordant Couples in Ethiopia, 2020: A Mixed-Method Study

BACKGROUND

Heterosexual transmission within serodiscordant relationships is the core source of new HIV infections. Although consistent condom use can significantly reduce HIV transmission risk among serodiscordant couples, it has not been extensively studied in Ethiopia. Consequently, the current study looked at the proportion of serodiscordant couples in Ethiopia who used condoms consistently and the factors associated with that.

METHODS

A cross-sectional was conducted from October 2019 to June 2020. For the quantitative findings to be more robust and reliable, a qualitative design was incorporated. An interviewer-administered questionnaire was used to collect the data. Qualitative data were collected using gender-matched four focus group discussions. Multivariable logistic regression was conducted to identify factors associated with consistent condom use. The statistical significance of the variables was declared at a P value of less than 0.05.

RESULTS

This study confirmed that the proportion of consistent condom use was 58.4% [95% CI: 53.1-63.1%]. After controlling for all other variables, unmarried partners, adjusted odds ratio (AOR) = 0.44 [95% CI: 0.229-0.877] and students and employees, AOR = 0.33 [95% CI: 0.130-0.846] and AOR = 0.39 [95% CI: 0.165-0.939], respectively, were less likely consistently use condoms, whereas couples living together, AOR = 1.86 [95% CI: 1.197-2.195], receiving counseling about condom use, AOR = 1.90 [95% CI: 1.182-3.076], and having more knowledge about HIV, AOR = 1.61 [95% CI: 1.031-2.525] were more likely to use condoms consistently.

CONCLUSION

Despite its importance, the proportion of consistent condom use among serodiscordant couples was significantly low. To improve condom use consistently, planners, policymakers, and health care practitioners should consider the factors listed above when making decisions. There should be an increased focus on student and employee intervention as well.

Minimizing cross transmission of SARS-CoV-2 in obstetric ultrasound during COVID-19 pandemic

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-associated infection (COVID-19) is affecting populations worldwide. This statement may serve as guidance for infection prevention and safe ultrasound practices during the COVID-19 pandemic. Ultrasound examination is a fundamental part of obstetric care, yet it is a potential vector for transmission of SARS-CoV-2. Decontamination methods should always be implemented for ultrasound equipment, especially in the presence of suspected or confirmed COVID-19 cases. There must be workflow policies to protect pregnant women and healthcare providers from nosocomial cross transmission of SARS-CoV-2. Cleaning and disinfecting of equipment must be in accordance with their potential of pathogen transmission. Consider using telemedicine and genetic technologies as an adjunctive of obstetric ultrasound to reduce patient crowding. Patient triage and education of healthcare providers of infection prevention are crucial to minimize cross contamination of SARS-CoV-2 during obstetric ultrasound.

Nanotechnology and the future of condoms in the prevention of sexually transmitted infections

Objective

The human immunodeficiency virus (HIV) is among the utmost destructive viruses humankind has ever faced in almost four decades. It carries with it profound socioeconomic and public health implications. Unfortunately, there is, currently, no effective cure for HIV infections. This review discusses the various types of condoms, microbicides, and the potential use of nanoparticle-coated condoms as a means of diminishing the risk of HIV transmission and sexually transmitted infections (STIs) during sexual intercourse.

Methods

We identified 153 articles from 1989 to 2015 indexed in various journal platforms, reports, and magazines. Using the PRISMA guidelines as proxy in performing the research review process, only 53 articles were selected. Ideally, articles that failed to describe the nature and types of condoms, condom failures, nanoparticle-coated condoms, microbicides, and HIV prevention were excluded.

Results and Discussion

In general, it has been shown that antiretroviral therapy (ART) currently available can only limit transmission and acquisition of HIV strains. Apart from ART treatment, the use of condoms has been identified globally as a cost-effective intervention for reducing the spread of HIV and other STIs. However, while condoms are supposed to be effective, reliable, and easy to use, research has shown that they are attributable to 20% failures including breakages. Nevertheless, other studies have shown that coating condoms with nanoparticles is an important and effective method for reducing condom breakage and HIV/STI transmission during sexual intercourse.

Conclusions

A review of literature cited in this paper has shown that nanotechnology-based condom systems have the potential to prevent the spread of HIV and STIs. Furthermore, the antimicrobial nature of some nanoparticles could provide a safe and efficient way to disrupt and/or inactivate different STIs - including viral, bacterial, and fungal diseases.

Impermeable Robust Hydrogels via Hybrid Lamination

Hydrogels have been proposed for sensing, drug delivery, and soft robotics applications, yet most of these materials suffer from low mechanical robustness and high permeability to small molecules, limiting their widespread use. This study reports a general strategy and versatile method to fabricate robust, highly stretchable, and impermeable hydrogel laminates via hybrid lamination of an elastomer layer bonded between hydrogel layers. By controlling the layers' composition and thickness, it is possible to tune the stiffness of the impermeable hydrogels without sacrificing the stretchability. These hydrogel laminates exhibit ultralow surface coefficients of friction and, unlike common single-material hydrogels, do not allow diffusion of various molecules across the structure due to the presence of the elastomer layer. This feature is then used to release different model drugs and, in a subsequent experiment, to sense different pH conditions on the two sides of the hydrogel laminate. A potential healthcare application is shown using the presented method to coat medical devices (catheter, tubing, and condom) with hydrogel, to allow for drug release and sensing of environmental conditions for gastrointestinal or urinary tract.

Zika virus and pregnancy: An overview

In May 2015, the first episodes of Zika virus infection of the Latin America were confirmed in Brazil, where currently 196 976 cases were reported. The main route of transmission occurs by Aedes mosquitoes, and the most common symptoms are maculopapular rash, fever, conjunctivitis, polyarthralgia, and periarticular edema. However, the infection is asymptomatic in 80% of the cases. The congenital infection is characterized when the transmission to the fetus occurs during pregnancy, but the mechanisms of how the virus infects the placenta remain unclear. Anatomopathological findings were described in first- and third-trimester human placentas; however, the major affected tissue of the baby is the neural. Several clinical situations were listed in these fetuses, such as neurological, ophthalmological, auditory, and articular alterations. The World Health Organization proposed a new congenital syndrome caused by Zika virus. The virus has an important neurotropism and the main manifestation observed in the syndrome is microcephaly, which is usually severe and associated with other neurological injuries. The appearance of sudden rash in pregnant women determines immediate investigation through RT-PCR and serological analysis. Moreover, the prevention consists in using repellents and avoiding endemic areas, considering that the vaccine is still under development.

Systematic review of the literature on viral persistence and sexual transmission from recovered Ebola survivors: evidence and recommendations

OBJECTIVE

The main aim of this article is to present a comprehensive, systematic review on evidence of sexual transmission from Ebola survivors and persistence of Ebola virus in body fluids of relevance to sexual transmission, and additionally to review condom effectiveness against sexual transmission of Ebola.

DESIGN

We performed a systematic review of viral persistence in body fluids of relevance to sexual transmission of Ebola survivors and evidence of sexual transmission of Ebola, and carried out a targeted review of condom effectiveness.

RESULTS

We identified nine published original articles presenting results on persistence of Ebola virus in relevant body fluids, or reporting suspect sexual transmission from Ebola survivors. We also included unpublished reports from the current 2014/2015 Ebola epidemic in West Africa. We found no articles reporting on condom effectiveness, but have included a targeted review on general condom efficacy and effectiveness.

CONCLUSIONS

We conclude that the risk of sexual transmission from people who have recovered from Ebola cannot be ruled out. We found the longest duration of persistent Ebola RNA in a relevant body fluid from a survivor, to be reported from a man in Sierra Leone who had reverse transcriptase PCR (RT-PCR) positive semen 284 days after symptom onset. In line with current WHO recommendations. We recommend that men are offered the possibility to test their semen regularly for presence of Ebola RNA from 3 months post-symptom onset. Safe sex practices including sexual abstinence, or else condom use, are recommended by WHO until semen has tested negative twice, or in absence of testing for at least 6 months post-symptom onset. Based on evidence reviewed, we conclude that male and female latex condoms offer some protection against EBOV compared to no condom use. Survivors should be offered access to care and prevention, in order to provide them with possibilities to mitigate any risks that may occur, and efforts should be linked to destigmatising activities.

Condom effectiveness in reducing heterosexual HIV transmission: a systematic review and meta-analysis of studies on HIV serodiscordant couples

OBJECTIVE

This systematic review and meta-analysis aimed to reassess the effectiveness of condoms in reducing heterosexual transmission of HIV.

METHODS

Medline, Scopus, and the ISI Web of Science databases were searched up to June 2014. Eligible studies were synthesized using random-effects models.

RESULTS

Twenty-five studies with 10,676 HIV serodiscordant heterosexual couples were analyzed. The risk of HIV transmission was considerably lower among couples that were always using condoms compared to never-users (RR: 0.29, 95% CI: 0.20-0.43) or inconsistent users (RR:  0.23, 0.13-0.40). The protective effect was slightly higher when the male rather than the female partner was infected (RR: 0.31, 0.20-0.48; vs. RR: 0.44, 0.24-0.80), and very high in Asian settings (RR: 0.06, 0.01-0.46).

CONCLUSIONS

Though imperfect, condoms reduce HIV transmission by more than 70% when used consistently by HIV serodiscordant heterosexual couples. Social, cultural and biological differences need to be studied further to inform projection modelers and policy makers.

The Association Between Alcohol Consumption and Condom Use: Considering Correlates of HIV Risk Among Black Men Who Have Sex with Men

Epidemiological data indicate Black men who have sex with men (MSM) are the most at-risk group for HIV infection. However, the factors driving this disparity are not fully understood. Condom use remains a significant point of intervention in mitigating sexually transmitted infections. Alcohol consumption is highly prevalent among Black MSM, has a significant role in the culture of sex, and may significantly interfere with condom use. This review will examine the relationship between alcohol consumption and condom use among Black MSM. In this review we, (a) discuss the prevalence of alcohol use among MSM and its association with condom use; (b) consider the role of alcohol in the culture of MSM; (c) review the literature on the relationship between alcohol and condom use; and (d) discuss the role of several empirically-supported moderating variables in strengthening the relationship between alcohol use and noncondom use. This review places the finding and implications for HIV risk among Black MSM in the context of the broader literature on MSM.

Condom use around the globe: how can we fulfil the prevention potential of male condoms?

Despite a global epidemic of sexually transmissible infections and the availability and endorsement of condoms as an effective intervention, the overall use of condoms remains low. This review explores various challenges and opportunities to fully realizing the prevention potential for condoms.

Where does public funding for HIV prevention go to? The case of condoms versus microbicides and vaccines

This study analyses the priorities of public donors in funding HIV prevention by either integrated condom programming or HIV preventive microbicides and vaccines in the period between 2000 and 2008. It further compares the public funding investments of the USA government and European governments, including the EU, as we expect the two groups to invest differently in HIV prevention options, because their policies on sexual and reproductive health and rights are different. We use two existing officially UN endorsed databases to compare the public donor funding streams for HIV prevention of these two distinct contributors. In the period 2000-2008, the relative share of public funding for integrated condom programming dropped significantly, while that for research on vaccines and microbicides increased. The European public donors gave a larger share to condom programming than the United States, but exhibited a similar downward trend in favour of funding research on vaccines and microbicides. Both public donor parties invested progressively more in research on vaccines and microbicides rather than addressing the shortage of condoms and improving access to integrated condom programming in developing countries.

Heterosexual spread of HIV infection

Sexual transmission is the most common route of spread of human immunodeficiency virus (HIV), with heterosexual transmission of HIV infection accounting for 90% of those infected in 1992 and over 75% of the 10–12 million of those infected to date worldwide. Yet, heterosexual transmission is poorly understood. Since HIV can be transmitted from HIV-infected people who are asymptomatic as well as from those who have the acquired immunodeficiency syndrome (AIDS), we must better define the potential for transmission of HIV from HIV-infected individuals as well as the factors which influence the susceptibility of HIV-uninfected individuals.

Biomedical interventions to prevent HIV infection: evidence, challenges, and way forward

Intensive research efforts for more than two decades have not yet resulted in an HIV vaccine of even moderate effectiveness. However, some progress has been made with other biomedical interventions, albeit on the basis of inconsistent levels of evidence. The male condom, if used correctly and consistently, has been proven in observational studies to be very effective in blocking HIV transmission during sexual intercourse; and, in three randomised trials, male circumcision was protective against HIV acquisition among men. Treatment of sexually transmitted infections, a public health intervention in its own right, has had mixed results, depending in part on the epidemic context in which the approach was assessed. Finally, oral and topical antiretroviral compounds are being assessed for their role in reduction of HIV transmission during sexual intercourse. Research on biomedical interventions poses formidable challenges. Difficulties with product adherence and the possibility of sexual disinhibition are important concerns. Biomedical interventions will need to be part of an integrative package that includes biomedical, behavioural, and structural interventions. Assessment of such multicomponent approaches with moderate effects is difficult. Issues to be considered include the nature of control groups and the effect of adherence on the true effectiveness of the intervention.

Self-reported condom use is associated with reduced risk of chlamydia, gonorrhea, and trichomoniasis

OBJECTIVES

To evaluate the association between self-reported condom use and prevalent and incident chlamydia, gonorrhea, and trichomoniasis.

STUDY DESIGN

Prospective study of 414 males attending a sexually transmitted infection (STI) clinic in Jamaica. Condom use and STI status were assessed at enrollment and at 4 follow-up visits.

RESULTS

The analyses on condom use and prevalent STI included data from 414 men, while those on incident STI were based on 1111 intervals from 355 men. We diagnosed prevalent STI (chlamydia, gonorrhea, and/or trichomoniasis) in 54.6% (n = 226) of the participants at enrollment. About 14% (n = 51) of participants had at least 1 of the study STIs during follow-up. Follow-up visits in which participants reported consistent condom use (100% of acts) for the past 7 days had less incident STI (adjusted OR, 0.4; 95% CI, 0.2-0.9) compared with visits where no condom use was reported. Self-reported condom use was more closely correlated with incident than prevalent STI. For example, the adjusted OR for prevalent infection for participants reporting consistent versus no condom use in past 7 days was 0.7 (95% CI, 0.4-1.2). Classifications based on the number of unprotected acts yielded findings similar to those based on the proportion of acts protected.

CONCLUSIONS

Consistent condom use was associated with reduced risk of incident urethral STI. Research on condom effectiveness should focus on incident STI outcomes, where the temporal relationship between condom use and infection is clearer.

Condom perforation during transrectal ultrasound guided (TRUS) prostate biopsies: a potential infection risk

INTRODUCTION

Transrectal ultrasound (TRUS) guided prostate biopsies are amongst the most common outpatient diagnostic procedures performed in urology practice. Of concern appear to be recent reports of infectious complications following this procedure in which contamination of the biopsy equipment was the likely source. This study looks at the rate of condom perforation during prostate biopsy and we look to highlight the potential problems, which may arise as a result of inadequate cleansing of the equipment between cases during a busy prostate biopsy clinic

MATERIAL AND METHODS

All patients attending for prostate biopsies over a three-month period in our institution were included in the study. All condoms (latex) used were made by the same manufacturer and were checked prior to the procedure and found to have no leaks. The biopsy gun was inserted through an externally placed needle guide, as is standard practice in many departments in the UK. After the end of each procedure the condom was removed from the rectal probe and filled once again with water to assess for perforations. Two experienced surgeons carried out all the procedures.

RESULTS

10 out of 107 patients were found to have at least one perforation in the condom. In some of the condoms there were multiple perforations.

DISCUSSION

We have demonstrated a significant condom perforation rate (9%) amongst patients undergoing prostate biopsies. This raises the serious issue of hygiene and cross infection, particularly with blood borne communicable diseases such as hepatitis and HIV unless strict disinfection and sterilization protocols are followed between patients. Perforation of the condoms used during TRUS guided prostate biopsy and hence faecal and blood contamination of the biopsy equipment could potentially have far-reaching implications for urologists and the infection control community. Although the risk of cross infection is probably small this serious issue needs addressing.

Condom use and risk of gonorrhea and Chlamydia: a systematic review of design and measurement factors assessed in epidemiologic studies

BACKGROUND

Studies of condom use to reduce risk of most sexually transmitted infection provide inconsistent results. This inconsistency is often attributed to methodologic limitations yet has not been assessed systematically.

OBJECTIVES

The objectives of this study were to review studies of condom use and risk of gonorrhea and chlamydia, and to evaluate the importance of 4 key design and measurement factors on condom effectiveness estimates.

DESIGN

We reviewed studies published 1966-2004 to assess risk reduction for gonorrhea and/or chlamydia associated with male condom use.

RESULTS

Of 45 studies identified, most found reduced risk of infection associated with condom use. All studies reviewed had methodologic limitations: only 28 (62%) distinguished consistent from inconsistent use; 2 (4%) reported on correct use or use problems; 13 (29%) distinguished incident from prevalent infection; and one (2%) included a population with documented exposure to infection. Eight of 10 studies with 2 or more of these attributes reported statistically significant protective effects for condom use versus 15 of 35 studies with zero or one attribute (80% vs. 43%, P = 0.04).

CONCLUSIONS

Condom use was associated with reduced risk of gonorrhea and chlamydia in men and women in most studies, despite methodologic limitations that likely underestimate condom effectiveness. Epidemiologic studies that better address these factors are needed to provide more accurate assessment of condom effectiveness.

Culture, community networks, and HIV/AIDS outreach opportunities in a south Indian Siddha organization

BACKGROUND

Gandeepam is an NGO in rural south India, with an HIV prevalence rate estimated at 2-7 times the national average. Aside from several outreach programs, Gandeepam practices Siddha medicine.

OBJECTIVE

Evaluate Gandeepam's strengths and opportunities to promote HIV education.

DESIGN

Three weeks of observing clinic practice, meeting patients, and discussing organizational structure. A survey of attitudes toward HIV was completed.

RESULTS

Gandeepam reaches a broad cross-section of its community, and effectively disseminates information. No primary HIV prevention efforts were observed.

CONCLUSION

Current strengths include an established network for information dissemination, and a strong community reputation. Tremendous social obstacles for disseminating effective HIV prevention messages remain.

Determinants of condom use among a random sample of single heterosexual adults

OBJECTIVES

The aim of this study was to identify the determinants of single heterosexuals' use of condoms during each sexual intercourse.

DESIGN

Cohort of individuals followed over a period of 2 years.

METHODS

Respondents were 574 single heterosexual individuals who answered questions during a telephone interview.

RESULTS

Attitude, perceived behavioural control, self-efficacy and moral norm explained 65% of the variance in intentions to use condoms ( p, .0001). The determinants of condom use at 1 year follow-up (27% explained variance) were perceived behavioural control, past behaviour, and the interaction between intention and intention stability. At 2 years follow-up, the significant determinants were past behaviour and intention by intention stability. In the present study, intentions to use condoms which remained stable across time were strong predictors of condom use (at 1 year: beta = .42, p < .0001; at 2 years: beta = .39, p, < .003), while unstable intentions were not (at 1 year: beta = .02, ns; at 2 years: beta = .19, ns).

CONCLUSION

Intention stability is a major determinant of the accuracy of intention for the prediction of subsequent behaviour.

Factors associated with maintenance of regular condom use among single heterosexual adults: a longitudinal study

OBJECTIVE

The aims of this study were to describe behavioural and psychosocial characteristics of single heterosexuals towards regular condom use, and to identify factors associated with the maintenance of this behaviour over time.

METHOD

A cohort of 179 single heterosexual adults (83 men and 96 women, mean age: 32 years) was followed over a period of 2 years. The data were collected, by phone interviews, at baseline and 1 and 2 years later. The phone numbers were generated using a random digit strategy.

RESULTS

The following changes were observed: over time fewer people were sexually active, but those who were, reported more often having had more than one sexual partner. No significant change was observed regarding condom use. The psychosocial variables remained stable during the study period. To have a favourable intention was the main factor associated with maintenance of condom use. Having had a STD, personal normative beliefs and positive attitude were also associated with regular condom use.

DISCUSSION

Promotion strategies should highlight the importance of acting as a responsible person, reinforce the advantages of using condoms, and select strategies that favour the implementation of intention of using condoms.

HIV incidence and sexually transmitted disease prevalence associated with condom use: a population study in Rakai, Uganda

OBJECTIVE

Evidence of condom effectiveness for HIV and sexually transmitted disease (STD) prevention is based primarily on high-risk populations. We examined condom effectiveness in a general population with high HIV prevalence in rural Africa.

METHODS

Data were from a randomized community trial in Rakai, Uganda. Condom usage information was obtained prospectively from 17,264 sexually active individuals aged 15-59 years over a period of 30 months. HIV incidence and STD prevalence was determined for consistent and irregular condom users, compared to non-users. Adjusted rate ratios (RR) of HIV acquisition were estimated by Poisson multivariate regression, and odds ratios of STDs estimated by logistic regression.

RESULTS

Only 4.4% reported consistent condom use and 16.5% reported inconsistent use during the prior year. Condom use was higher among males, and younger, unmarried and better educated individuals, and those reporting multiple sex partners or extramarital relationships. Consistent condom use significantly reduced HIV incidence [RR, 0.37; 95% confidence interval (CI), 0.15-0.88], syphilis [odds ratio (OR), 0.71; 95% CI, 0.53-0.94] and gonorrhea/Chlamydia (OR, 0.50; 95% CI, 0.25-0.97) after adjustment for socio-demographic and behavioral characteristics. Irregular condom use was not protective against HIV or STD and was associated with increased gonorrhea/Chlamydia risk (OR, 1.44; 95% CI, 1.06-1.99). The population attributable fraction of consistent use for prevention of HIV was -4.5% (95% CI, -8.3 to 0.0), due to the low prevalence of consistent use in the population.

CONCLUSIONS

Consistent condom use provides protection from HIV and STDs, whereas inconsistent use is not protective. Programs must emphasize consistent condom use for HIV and STD prevention.

Virus transmission through compromised synthetic barriers: part II--influence of pore geometry

When stressed during normal use, synthetic barriers such as gloves and condoms can develop tears that are undetectable by the user. It is of considerable public-health importance to estimate the quantity of virus transmitted through the tear, in the event of viral contamination of the fluid medium. A mathematical model that accounts for virus adsorption to the barrier material was used to compute the quantity of virus transmitted through defects of various geometries. Slits were modeled as cylinders of elliptic cross section, and upper and lower bounds for the transmission rate of HIV and Hepatitis B virus (HBV) were calculated for barrier-use scenarios such as coitus and gripping of surgical instruments. For a 1-microm high slit, HIV transmission was found to be negligible for all likely use scenarios. HIV transmission became potentially significant for a 5-microm slit. Due to its high titer, HBV transmitted at potentially important levels even through the 1-microm slit. The dependence of the transmission rate upon pore aspect ratio was determined and found to be very strong for high-adsorption situations and near-circular pores. Numerical predictions of virus transport through a laser-drilled hole in a condom matched experimental measurements well, even when the tapered nature of the geometry is ignored.

The fate of free male condoms distributed to the public in South Africa

OBJECTIVES

Public sector male condom distribution in South Africa rose from six million in 1994 to 198 million in 1999 as part of the government's condom promotion efforts for HIV/AIDS prevention. This study investigates what happens to the condoms which are distributed free of charge by the South African Department of Health.

METHODS

A prospective study was undertaken during 1998-1999 at 12 representative public health facilities. Five-hundred and fifty-four consecutive subjects leaving the facilities were recruited and followed-up for 5 weeks to ascertain the fate of the 8164 condoms they had procured.

RESULTS

A total of 384 participants (69.3%) and their 5528 condoms (67.7%) were followed successfully. After 5 weeks, 43.7% of the condoms had been used or broken in sex, 21.8% had been given away, 8.5% had been lost or discarded, and 26.0% were still available for use. Increased rates of condom use by participants were associated with active (compared to passive) condom procurement.

CONCLUSIONS

In light of the rapidly increasing number of free condoms being distributed by the public health service in South Africa, it is reassuring to note that wastage at 5 weeks is less than 10%. Extrapolating these data to the 198 million public sector condoms distributed in South Africa in 1999, at least 87 million condoms were used in sex. This methodology may be used to help evaluate the impact of existing condom distribution systems and the effectiveness of various condom promotion strategies.

Use of a condom in sex relations by HIV carriers

The frequency with which condoms are used in sex relations by subjects with HIV was determined by interviewing 132 individuals, 82 men and 50 women, most of them from São Paulo state and some from other regions of the country, all of them seen at an outpatient clinic of the School of Medicine in Botucatu. The women were younger, were of lower educational level and had poorer professional qualification than men. Also, a greater proportion of women were widowed, separated or divorced. We observed that 43.9% of men and 72% of women had been contaminated by the sexual route, but only 41.2% of the men and 31.8% of the women reported the use of a condom after the diagnosis of infection, with most men and women preferring sexual abstinence. The results enable the conclusion that there is still a need to continue to provide information about the use of condoms and to guarantee their free-of-charge distribution due to the low levels of education and professional qualification of the individuals studied. The data also suggest that campaigns for the dissemination of preventive measures should consider the social and cultural differences of infected women.

Mechanical failure of the latex condom in a cohort of women at high STD risk

BACKGROUND AND OBJECTIVES

Mechanical failure may reduce the efficacy of condoms. Little is known about frequency and determinants of condom failure in groups at high risk of sexually transmitted diseases (STD).

GOAL

To measure condom breakage and slippage rates and evaluate potential determinants of failure among women attending a public STD clinic.

STUDY DESIGN

Women attending an STD clinic participated in a 6-month prospective study of barrier contraception for the prevention of STD. They completed sexual diaries that were reviewed at monthly follow-up visits. No data were collected from the male partners. Baseline characteristics of the participants and time-dependent behaviors were evaluated as potential determinants of condom failure.

RESULTS

Of 21,852 condoms used by 892 women, 500 broke during intercourse (2.3%) and 290 slipped (1.3%). Breakage was more common among young, black, single nulliparae who engaged in high-risk behavior. Slippage was more common among married women with children. Failure rates decreased with condom use, with coital frequency, and with use of spermicides.

CONCLUSION

User characteristics and experience are determinants of breakage and slippage, which are often regarded only as the effect of product design flaws. Attention to modifiable determinants of failure may improve user counseling and product labeling.

Implications of laboratory tests of condom integrity

BACKGROUND

There is sufficient evidence from Food and Drug Administration laboratory experiments and clinical studies to draw conclusions about the relative importance of holes and breakage to condoms. The laboratory test methods determined penetration of viruses or virus-size microspheres through holes in condoms under conditions that simulated or exaggerated those expected in actual use, and determined the frequency with which condoms might pass virus or microspheres and the amounts of passage in each case.

GOALS

To summarize and comment on the significance of test results on latex, polyurethane, and natural membrane condoms as barriers to virus passage.

STUDY DESIGN

Published and unpublished data addressing three distinct concerns were analyzed: (1) passage of virus or microspheres through small holes or pores inherent in the material of "intact" condoms which are undetectable by the standard water leak quality assurance test, (2) passage of virus or microspheres through larger holes in "leaker" condoms detectable by the water leak test but marketed because of the finite acceptable quality level (AQL) of the test, and (3) passage of virus through condoms that break during use.

RESULTS

Extrapolating to the passage of semen expected during actual use allowed an analysis of the relative importance of breakage and water-leak-detectable or water-leak-undetectable holes.

CONCLUSIONS

The relative importance of breaks and holes is related to the volume of semen that contains an "infectious dose" of a sexually transmitted disease (STD). When 0.1 mL to 1.0 mL exposures to semen are necessary for disease transmission, the risk during latex condom use primarily results not from holes, but from breakage of condoms. For smaller volumes of semen exposure (0.00001 mL and less), the presence of holes can be as important as breaks. The same qualitative argument pertains to a comparison of "leaker" condoms to the large majority of "intact" condoms.

Prospective study of barrier contraception for the prevention of sexually transmitted diseases: study design and general characteristics of the study group

BACKGROUND AND OBJECTIVES

The AIDS epidemic has brought barrier contraceptives to the forefront of public health research. A comprehensive evaluation of the efficacy of barrier contraceptive use in preventing sexually transmitted diseases (STDs), including AIDS, is necessary to inform both potential users and public health policy makers. This study was undertaken to evaluate the efficacy of condoms and vaginal spermicide products, used alone or in combination, in preventing gonorrhea and chlamydia among women attending an STD clinic.

GOAL OF THIS STUDY

To describe the general characteristics of the study group and its follow-up experience.

STUDY DESIGN

Women who met the eligibility criteria were invited to participate. The initial visit included an interview, a behavioral intervention promoting barrier methods, a physical examination, and instructions to complete a sexual diary. Participants received free barrier contraceptives and returned for six monthly follow-up visits. DESIGN RESULTS: Participants (n = 1,122) were low income, single (74%) black (89%) women with a median age of 24. The behavioral intervention led to the use of barrier protection in more than 70% of reported acts of vaginal intercourse. Barriers were used consistently (100% of sexual acts) during 51% of the months of follow-up. A total of 148 cases of gonorrhea (28 per 1,000 months) and 122 cases of chlamydia infection (23 cases per 1,000 months) were diagnosed during follow-up.

CONCLUSION

This study represents a practical solution to a complex set of design considerations. The study protocol was successful in promoting consistent and proper use of barrier methods.

Adolescent abstinence and condom use: are we sure we are really teaching what is safe?

This article reviews existing research on condom and abstinence method- and user-failure rates, and the use of this research in determining sexuality education curricula. Latex condoms effectively prevent pregnancies and most sexually transmitted diseases or infections (STIs), with method-failure rates between 0.5% and 7%, but with user-failure rates between 12% and 70%. Total abstinence presumably has a method-failure rate of zero, but research on periodic abstinence indicates user-failure rates between 26% and 86%. No researchers have attempted to establish total abstinence user-failure rates. Abstinence-only curricula evaluations have demonstrated changes in adolescents' attitudes but little change in sexual behaviors. Comprehensive sexuality education curricula have demonstrated attitudinal changes and delays in adolescents' sexual activity. Since inconsistent use of either condoms or abstinence threatens adolescents' health, this article urges more scientific research on total abstinence user-failure rates, better and clearer dissemination of research findings, and encourages funders to require educators to show thorough knowledge of research findings.

Anogenital warts and condom use--a survey of information giving

OBJECTIVE

To examine information giving by genitourinary medicine (GUM) consultants about the use of condoms for patients with anogenital warts (AGW).

METHOD

228 GUM consultants in the UK and Ireland were sent a questionnaire concerning the information about condom use which they usually discuss with patients with AGW. The survey was carried out in 1994.

RESULTS

There was a 46% response rate. Most consultants indicated giving information specifically with regard to the prevention of transmission of human papilloma virus (HPV), and not only in the context of safe sex. With regard to current AGW, consultants were more likely to discuss, than not to discuss, use of condoms with patients with regular sexual partners in terms of benefit, uncertain benefit, or no benefit. However, no significant difference in the likelihood of discussing, or not discussing, these issues was found for current AGW for patients without regular partners. For both groups, benefit of using condoms for current AGW was more likely to be discussed than no benefit. The majority of consultants indicated that they would discuss condom use after disappearance of AGW as being of uncertain benefit. However, many consultants also indicated discussing use of condoms for a specific period or an indefinite period of time, including many of those who specific discussing uncertain beneficial use of condoms after disappearance of AGW. The most common duration of condom use chosen for discussion was until 3 months after disappearance of AGW.

CONCLUSION

GUM consultants vary in the information they give about condom use specifically to prevent transmission of HPV. This survey suggests a need for evaluation by GUM physicians of management guidelines relating to information given about condom use for AGW, including utilising the available scientific evidence as well as dealing with issues of uncertainty.

Effectiveness of condoms in preventing HIV transmission

The consistent use of latex condoms continues to be advocated for primary prevention of HIV infection despite limited quantitative evidence regarding the effectiveness of condoms in blocking the sexual transmission of HIV. Although recent meta-analyses of condom effectiveness suggest that condoms are 60 to 70% effective when used for HIV prophylaxis, these studies do not isolate consistent condom use, and therefore provide only a lower bound on the true effectiveness of correct and consistent condom use. A reexamination of HIV seroconversion studies suggests that condoms are 90 to 95% effective when used consistently, i.e. consistent condom users are 10 to 20 times less likely to become infected when exposed to the virus than are inconsistent or non-users. Similar results are obtained utilizing model-based estimation techniques, which indicate that condoms decrease the per-contact probability of male-to-female transmission of HIV by about 95%. Though imperfect, condoms provide substantial protection against HIV infection. Condom promotion therefore remains an important international priority in the fight against AIDS.

An in vitro evaluation of condoms as barriers to a small virus

BACKGROUND

Because of the possible presence of small holes, the effectiveness of condoms as barriers to virus transmission is controversial.

GOALS

To determine the proportion of condoms that allow virus penetration and the amounts of virus that penetrate.

STUDY DESIGN

A sensitive, static test was used to evaluate different condom types as barriers to a small virus, including brand with or without lubrication and ones of different materials. The test included some physiologic-based parameters and some parameters that exaggerated expected actual use conditions.

RESULTS

Under test conditions, 2.6% (12 of 470) of the latex condoms allowed some virus penetration; the median level of penetration was 7 x 10(-4) ml. Lubricated condoms performed similarly to nonlubricated ones. Polyurethane condoms yielded results higher than but not statistically different from those for latex condoms.

CONCLUSIONS

Few condoms allowed any virus penetration. The median amount of penetration for latex condoms when extrapolated to expected actual use conditions was 1 x 10(-5) ml (volume of semen). Thus, even for the few condoms that do allow virus penetration, the typical level of exposure to semen would be several orders of magnitude lower than for no condom at all.

Adolescent females' attitudes, subjective norms, perceived behavioral control, and intentions to use latex condoms

Guided by I. Ajzen's (1991) theory of planned behavior, the authors of this descriptive correlational study explored adolescent females' attitudes, subjective norms (social pressure), perceived behavioral control, and intentions with regard to latex condom use. An elicitation study was initially conducted (n = 16) to ascertain salient beliefs related to condom use. These beliefs were then used to develop a questionnaire administered during the main study to 60 sexually active adolescent females attending a sexually transmitted disease clinic. Global attitudes, subjective norms, and perceived behavioral control predicted 50% of the variance of intentions to use condoms. Perceived behavioral control contributed the highest proportion of variance in the equation for both global and belief-based measures in stepwise regression analyses. Implications for community health practice, research, and theory are reported.

Women and the heterosexual transmission of HIV: risks and prevention strategies

Heterosexual intercourse has become a significant means of HIV transmission, even in countries where this was previously not the case. Consequently the promotion of safer sexual practices for heterosexual women and men is of major public health importance. We examine the risks to women of contracting HIV through heterosexual sex, and critically discuss the most commonly recommended strategies for safer sex for heterosexuals. We conclude that all safer sex strategies have limitations, and therefore a wide range of options should be promoted.

Screening and treatment of sexually transmitted diseases: an important strategy for reducing the risk of HIV transmission

The role of sexually transmitted diseases (STDs) in the spread of human immunodeficiency virus (HIV) infection is reviewed. The rationale for and approach to reducing STD prevalence in high-risk communities are presented. Given the asymptomatic nature of these infections and problems associated with delivering curative therapy, effective interventions will require the use of diagnostic tests for screening and the use of single-dose therapies in appropriate settings: Treatment of individuals with STDs will likely reduce individual risk, while reduction of STD prevalence in high-risk communities may curtail the epidemic spread of HIV.

Observations of scanning electron microscopy detected abnormalities of non-lubricated latex condoms

To describe surface abnormalities found by scanning electron microscopy of non-lubricated latex condoms, thirty samples of 15 condoms were photographed at low (26-94x), medium (240-940x) and high (> 1000x) magnification. Each sample was initially scanned at low magnification to determine the presence and location of surface abnormalities. Photographs taken at medium and high magnification were of the area most representative of the abnormality. Nine samples (30%) were completely normal at all magnifications. Of the total viewed at low power, 18 (60%) were normal, 11 (37%) revealed ridging and 1 (3%) revealed melting. Of the total viewed at medium power, 14 (47%) were normal, 3 (10%) showed cracking, 2 (7%) showed melting or a combination of ridging and cracking, and 11 (37%) showed ridging. At high power, 10 (34%) were normal, 11 (38%) revealed either melting or a combination of two defects, 5 (17%) showed ridging, and 3 (10%) revealed cracking. Fifteen (50%) of the samples revealed a surface abnormality (cracking or melting) other than ridging. The majority of condoms viewed under scanning electron microscopy revealed surface abnormalities. The implication of the detected abnormalities needs further evaluations. While ridging may represent a minor abnormality associated with condom handling, multiple abnormalities or melting may represent a more significant atypicality.

Lack of evidence for transmission of human immunodeficiency virus through vaginal intercourse

Research in determining risks for human immunodeficiency virus (HIV) transmission is confounded by many issues. They include lack of clarity or specificity in terminology used, respondents misunderstanding of questions, and lying. The base rate of lying (or social desirability responding) by itself is sufficient to account for the small percentage of Americans and Europeans claiming "heterosexual" transmission from partners not known to be intravenous drug users. This study integrates the physiological and epidemiological data on risk factors for HIV transmission with the psychological literature on the frequency of anal intercourse and of lying (in this case to researchers and clinicians about risk factors). When these factors are considered, intravenous and anal activities remain the only clear vectors for HIV transmission. Research suggesting that spermicidals are more effective at inactivating HIV than condoms are at physically containing HIV is also noted.

Barrier methods of contraception, spermicides, and sexually transmitted diseases: a review

OBJECTIVE

To understand whether barrier methods of contraception (BMC) and/or spermicides lower the risk of acquiring sexually transmitted disease (STD) and to quantify the protection.

DESIGN

Review of published experimental studies, in vitro and in vivo evidence on the issue.

SUBJECTS

We reviewed 22 papers that examined the impermeability of BMC in vitro against STD agents or the effect of spermicides, and 60 papers reporting results of epidemiological studies on the risk of STD in users of BMC.

RESULTS

There was in vitro evidence that both BMC and spermicides were effective against most sexually transmissible agents. Doubts remain on the effectiveness of BMC and spermicides in normal conditions of use, particularly against human papilloma virus. Natural membrane condoms are not impermeable and pores are seen by electron microscopy. Epidemiological studies show a consistent reduction in the risk for use of condoms against gonococcal (most studies giving relative risk, RR, estimates around 0.4 to 0.6) and HIV infection (RRs between 0.3 and 0.6 in most studies). Spermicides protect women against gonorrhoea and trichomoniasis; their role against other STDs is less clear and there is some indication of an irritative effect on the vaginal mucosa that is likely to be dose-dependent.

CONCLUSIONS

A large amount of evidence indicates that BMC reduce the risk of gonorrhoea and HIV transmission, but the results are--at least in quantitative terms--less consistent for other diseases. Implications for individual choices and public health approaches should relate to frequency of exposure and severity of the disease too.

Viral leakage risk differences in latex condoms

Through use of a new bacteriophage assay capable of detecting a single viral plaque-forming unit (PFU), viral leakage through multiple replicates of several types of latex condoms has been evaluated. Stocks were used that had been preserved from a previous large study in which viral leakage had been assessed preliminarily in several brands. In the present research, much larger numbers of replicates--on the order of magnitude of 100 condoms per brand--were used. Leakage was demonstrated in single production lots of each of seven brands of condoms. With one notable exception, percent leakage ranged from 0.9 to 22.8%; 100% of the specimens of one profoundly flawed brand leaked. All test condoms were subjected to conditions intended to model these prevailing during coitus. Because the condoms used in this study were aged, current stocks of two widely sold brands were tested for comparison. Of these, 11.8% of one brand leaked, 25.7% of the other. The relevance of the results, which gave a high, albeit physiologically appropriate, challenge to the test brands, is discussed--so too is the significance to condom users of results deriving from a leakage assay of exquisitely high sensitivity.

Efficacy of thermoplastic elastomer and latex condoms as viral barriers

The barrier efficacy of a thermoplastic elastomer (TPE) and three brands of latex condoms was compared in a passive-leak test and in a dynamic model of simulated intercourse. Fifteen replicates of each of the condoms were challenged with bacteriophage T7 (100 nm) and the polio virus Type 1 (PV-1, 27 nm). In the passive test, no condom leaked either virus. In the dynamic model, no TPE condoms leaked either virus and no latex condoms leaked T7. Two samples of one commercially available latex condom leaked T7 but not PV-1. These data support that intact latex condoms are effective in vivo viral barriers and extend the finding to TPE condoms as well. Given its substantial equivalence to latex as a viral barrier, TPE condoms are an alternative choice for individuals with latex allergies. The TPE material is also more resistant to common environmental conditions that affect latex adversely and should therefore be a superior choice if condoms must be stored for extended periods in suboptimal conditions.