Hisopado endocervical en mujeres con síntomas de COVID-19 provenientes de departamentos del Paraguay / Endocervical swabbing in women with COVID-19 symptoms from departments of Paraguay

INTRODUCCIÓN: El COVID-19 es eminentemente una infección de transmisión e inicio respiratorio, se discute la existencia de otras fuentes de contagio. El receptor viral ACE2 también ha sido detectado en el útero y en la vagina; de allí se ha planteado el compromiso del virus SARS-CoV-2 sobre el sistema genitourinario y sus posibles repercusiones en el embarazo. OBJETIVO: Determinar la presencia de SARS-CoV-2 en muestras endocervicales de mujeres con COVID-19 en departamentos del Paraguay. PACIENTES Y MÉTODOS: Diseño observacional prospectivo, de corte transverso. Se reclutaron 200 mujeres desde agosto 2020 hasta febrero 2021, con no más de 48/72 h de un resultado previo positivo de hisopado nasofaríngeo para SARS-CoV-2 por retrotranscriptasa reversa-reacción en cadena de la polimerasa (en inglés rt-RT-PCR) y que aceptaron ingresar al estudio. Se llenó un cuestionario clínico epidemiológico. Las tomas de muestras se realizaron en servicios de salud del Ministerio de Salud Pública y Bienestar Social (MSP y BS), domicilios y albergues de los distintos departamentos de Paraguay. Cada paciente fue sometida a un hisopado con hisopos de dacron o citobrush endocervical para la detección de SARS-CoV-2 por rt RT-PCR. Resultados: Las mujeres estudiadas tenían una edad media de 46,5 años (IC 95% 31,5-62,5). Refirieron contagio comunitario con SARS-CoV-2 en 75,5%, 13,5% en el hogar, 8,5% en el lugar de trabajo y 1,5% en el extranjero. Las manifestaciones clínicas fueron: 30%, síndrome gripal, fiebre 22,5%, tos 20%, anosmia 15,5%, trastornos digestivos 15,5%, y otros se presentaron con menor frecuencia. Las muestras de hisopados o citobrush endocervical sometidas a rt-RT-PCR para la deteccción de SARS Cov-2, resultaron negativas en las 200 mujeres de estudio. Discusión: Cabe destacar que las muestras vaginales fueron tomadas dentro de las 24-72 h de haber obtenido un resultado positivo para SARS-CoV-2 en el hisopado nasofaríngeo y que 62,5% de las mujeres se encontraban internadas en módulos respiratorios. Se discute la razón de la negatividad de los exámenes y su trascendencia. CONCLUSIÓN: No se detectó infección con SARS-CoV-2 en la región endocervical de 200 mujeres con manifestaciones clínicas de COVID 19 y evaluadas dentro de las 48/72 h de un resultado positivo nasofaríngeo para SARS Cov-2. Los resultados en la población de estudio concuerdan con otros estudios reportados en la literatura científica.

BACKGROUND: COVID-19 is an eminently respiratory transmissible infection of respiratory initiation, the existence of other sources of contagion is discussed. The ACE2 viral receptor has also been detected in the uterus and vagina; Hence, the involvement of the SARS-CoV-2 virus on the genitourinary system and its possible repercussions on pregnancy has been raised. AIM: To determine the presence of SARS-CoV-2 in endocervical samples of women with COVID-19 in the departments of Paraguay. METHODS: Designed as a prospective observational of transverse cohort. Two hundred women were recruited from August 2020 to February 2021, with no more than 48/72 hours of a previous positive nasopharyngeal swab result for SARS-CoV-2 by reverse transcriptase-polymerase chain reaction (rt-RT-PCR) and who agreed to participate in the study. A clinical epidemiological questionnaire was completed. The samples were taken in health services of the MSPYBS (Public Ministry of Health and Social Welfare), homes and shelters in the different departments of Paraguay. Each patient underwent a swab (dacron swabs) or endocervical cytobrush for the detection of SARS-CoV-2 by rt-RT-PCR. RESULTS: Women recruited had a mean age of 46.5 years (95% CI 31,562.5). They reported contagion with SARS-CoV-2: 75.5% in the community, 13.5% at home, 8.5% in the place of work and 1.5% abroad. The clinical manifestations were: 30% flu syndrome, 22.5% fever, 20% cough, 15.5% anosmia, 15.5% digestive disorders, among other symptoms. The swabs or endocervical cytobrush samples subjected to rt-RT-PCR for the detection of SARS-CoV-2 were negative in the 200 study women. Discussion: It should be noted that the vaginal samples were taken within 24-72 hours after obtaining a positive result for SARS-CoV-2 in the nasopharyngeal swab and that 62.5% of the women were hospitalized in respiratory modules. The reason for the negativity of the exams and their significance are discussed. CONCLUSION: No SARS Cov-2 infection was detected in the endocervical region of 200 women with clinical manifestations of COVID 19 and evaluated within 48/72 hours of a positive nasopharyngeal result for SARS Cov-2. The results in the study population agree with the findings of other studies reported in the literature.

Safety Assessment of Microbicide 2P23 on the Rectal and Vaginal Microbiota and Its Antiviral Activity on HIV Infection.

Containment of the AIDS pandemic requires reducing HIV transmission. HIV infection is initiated by the fusion of the membrane between the virus and the cell membrane of the host. 2P23 is an effective HIV membrane fusion inhibitor that may be a good entry inhibitor microbicide candidate. This study evaluated the potential of using gel-formulated 2P23 as a topical microbicide to prevent sexual transmission of HIV in the rectum and vagina. Our data revealed that 2P23 formulated in gel is effective against HIV. There was no change in antiviral activity at 25°C for 4 months or 60°C for 1 week. In addition, we demonstrated that the 2P23 gel was stable and fully functional at pH 4.0-8.0 and under different concentrations of H2O2. Finally, the 2P23 gel exhibited no cytotoxicity or antimicrobial activity and did not induce inflammatory changes in the rectal or vaginal mucosal epithelium in New Zealand rabbits after 20 mg/day daily rectovaginal application for 14 consecutive days. Despite repeated tissue sampling and 2P23 gel treatment, the inflammatory cytokines and microbiota of the rectum and vagina remained stable. These results add to general knowledge on the in vivo evaluation of anti-HIV microbicide application concerning inflammatory cytokines and microbiota changes in the rectum and vagina. These findings suggest that the 2P23 gel is an excellent candidate for further development as a safe and effective pre-exposure prophylactic microbicide for the prevention of HIV transmission.

Assessment of the possible inhibitory effect of carrageenan in human papillomavirus DNA testing by polymerase chain reaction amplification.

We assessed carrageenan's potential to inhibit human papillomavirus (HPV) DNA extraction and amplification in vaginal swab samples collected in a trial, assessing the efficacy of a carrageenan-based gel against HPV infections. Experiment #1 consisted of adding gel (carrageenan-containing or placebo) to swabs and comparing HPV DNA detection by polymerase chain reaction (PCR) to unmanipulated samples collected from the same participants. For Experiments #2 and #3, we tested vaginal samples for inhibition by addition of an internal control and amplification by real-time PCR. Experiment #4 investigated carrageenan's interference with the extraction process by assessing HPV45 detectability in undiluted and diluted HPV45 positive samples (n = 3) with carrageenan versus no gel. In Experiment #1, there was a loss of HPV positivity with the addition of carrageenan (n = 9), but none with placebo gel (n = 5). In Experiments #2 and #3, the absence of the amplified product was observed in samples from the carrageenan arm: 3.3% (1/30) and 0.5% (1/199) of samples. In Experiment #4, HPV45 was not detected in undiluted carrageenan-containing samples, but after 1/50 dilution, the same HPV45 copy number was detected. Carrageenan does not affect the DNA extraction process, and inhibition of HPV DNA amplification by carrageenan occurs infrequently.

Comparative study of Revogene GBS LB assay and GeneXpert GBS LB assay for the detection of group B Streptococcus in prenatal screening samples.

BACKGROUND: Group B Streptococcal (GBS) infections in the United States are a leading cause of meningitis and sepsis in newborns. The CDC therefore recommends GBS screening for all pregnant women at 35-37 weeks of gestation and administration of intrapartum prophylaxis (in those that tested positive) as an effective means of controlling disease transmission. Several FDA approved molecular diagnostic tests are available for rapid and accurate detection of GBS in antepartum women. METHOD: In this study, we report a clinical comparison of the Xpert GBS LB assay and a novel FDA-cleared test, Revogene GBS LB assay. A total of 250 vaginal-rectal swabs from women undergoing prenatal screening were submitted to the University of Wisconsin's clinical microbiology laboratory for GBS testing. RESULTS: We found 96.8% of samples were concordant between the two tests, while 3.2% were discordant with a positive percent agreement of 98.0% and a negative percent agreement of 96.5% between the Revogene GBS LB assay and the GeneXpert GBS LB assay. CONCLUSION: Overall, we report that both assays perform well for the detection of GBS colonization in pregnant women.

Assessment of a new arbidol derivative against herpes simplex virus II in human cervical epithelial cells and in BALB/c mice.

As one of the highly contagious forms, herpes simplex virus type 2 (HSV-2) commonly caused severe genital diseases and closely referred to the HIV infection. The lack of effective vaccines and drug-resistance proclaimed the preoccupation for alternative antiviral agents against HSV-2. Molecules bearing indole nucleus presented diverse biological properties involving antiviral and anti-inflammatory activities. In this study, one of the indole molecules, arbidol derivative (ARD) was designed and synthesized prior to the evaluation of its anti-HSV-2 activity. Our data showed that the ARD effectively suppressed HSV-2-induced cytopathic effects and the generation of progeny virus, with 50% effective concentrations of 3.386 and 1.717 µg/mL, respectively. The results of the time-course assay suggested that the ARD operated in a dual antiviral way by interfering virus entry and impairing the earlier period of viral cycle during viral DNA synthesis. The ARD-mediated HSV-2 inhibition was partially attained by blocking NF-κB pathways and down-regulating the expressions of several inflammatory cytokines. Furthermore, in vivo studies showed that oral administration of ARD protected BALB/c mice from intravaginal HSV-2 challenge by alleviating serious vulval lesions and histopathological changes in the target organs. Besides, the treatment with ARD also made the levels of viral protein, NF-κB protein and inflammatory cytokines lower, in consistent with the in-vitro studies. Collectively, ARD unveiled therapeutic potential for the prevention and treatment of HSV-2 infections.

A Multiple Dose Phase 1 Assessment of Rilpivirine Long Acting in a Model of Preexposure Prophylaxis Against HIV.

The MWRI-01 study characterized the safety, acceptability, pharmacokinetic (PK), and pharmacodynamic (PD) profile of rilpivirine (RPV) long acting (LA) in a model of preexposure prophylaxis (PrEP). Prospective, open-label Phase 1 study. The safety and acceptability of three repeated doses of RPV LA were monitored. Blood, tissue (rectal, cervical, and vaginal), and biological fluids (vaginal and endocervical) were collected at baseline and at 1- to 2-month intervals throughout the study for PK and PD assessment. Eight women and four men received three intramuscular doses of 1,200 mg of RPV LA given 8 weeks apart. There were a total of 195 adverse events (AEs) reported, of which 138 (70.8%) were Grade 1 and 55 (28.2%) were Grade 2. The most common AE was injection site pain. Geometric mean (90% confidence interval) plasma RPV concentrations at 56 days after the first and third doses were 39 (33-45) ng/mL (female)/29 (17-40) ng/mL (male) and 59 (45-62) ng/mL (female)/40 (30-51) ng/mL (male), respectively. Exposure to RPV LA was associated with significant inhibition of HIV-1BaL viral replication in the ex vivo rectal explant model (p < .0001) that persisted for up to 4 months after the third dose of RPV LA. In contrast, no viral suppression was seen in cervicovaginal tissue. Multiple dose administration of RPV LA was safe and well tolerated, and was associated with prolonged suppression of viral replication in rectal explant tissue.

Hospitalization burden associated with malignant neoplasia and in situ carcinoma in vulva and vagina during a 5-year period (2009-2013) in Spain: An epidemiological study.

BACKGROUND: Vulvar and vaginal cancers are considered rare cancers in women. Human Papillomavirus is responsible for 30-76% of them. The aim of this study was to describe the burden of hospital admissions by malignant neoplasia (MN) and in situ carcinoma (ISC) of vulva and vagina from 2009 to 2013, in Spain METHODS: This observational, descriptive study used discharge information obtained from the national surveillance system for hospital data, Conjunto Mínimo Básico de Datos, CMBD, provided by the Ministry of Health. RESULTS: From 2009-2013, we found 9,896 hospitalizations coded as MN or ISC of vulva and vagina. Mean age of hospitalization was 69.94 ±â€¯15.16 years; average length of hospital stay (ALOS) was 10.02 ±â€¯12.40 days, and mean hospitalization costs were 5,140.31 ±â€¯3,220.61 euros. Mean hospitalization rate was 9.874 per 100,000 women aged >14 years old (95% CI: 9.689-10.058); mean mortality rate was 0.932 per 100,000 women aged >14 years old (95% CI: 0.872-0.991) and mean case fatality rate was 9.438% (95% CI: 8.862-10.014). CONCLUSION: MN and ISC of vulva and vagina are responsible for a considerable hospitalization burden. Information about these hospitalizations could be useful for cost effectiveness analysis and monitoring of HPV vaccination effectiveness.

Differences between vaccinated and unvaccinated women explain increase in non-vaccine-type human papillomavirus in unvaccinated women after vaccine introduction.

The aim of this study was to determine whether an observed increase in non-vaccine-type human papillomavirus (HPV) in unvaccinated women during the first eight years after vaccine introduction may be explained by differences in demographics or sexual behaviors, instead of type replacement. We analyzed data from three cross-sectional surveillance studies of 13-26 year-old women (total N = 1180). For women recruited from a health department clinic, older age (OR = 1.4, 95% CI: 1.2-1.6) and consistent condom use with main partner in the past 3 months (OR = 11.6, 95% CI: 3.4-40) were associated with being unvaccinated. For women recruited from a teen health center African American race (OR = 0.2, 95% CI: 0.07-0.7) and having Medicaid health insurance (OR = 0.3, 95% CI: 0.1-0.7) were inversely associated with being unvaccinated. The observed increase in non-vaccine-type HPV prevalence in unvaccinated women may be explained by differences between unvaccinated and vaccinated women.

A spatio-temporal assessment of simian/human immunodeficiency virus (SHIV) evolution reveals a highly dynamic process within the host.

The process by which drug-resistant HIV-1 arises and spreads spatially within an infected individual is poorly understood. Studies have found variable results relating how HIV-1 in the blood differs from virus sampled in tissues, offering conflicting findings about whether HIV-1 throughout the body is homogeneously distributed. However, most of these studies sample only two compartments and few have data from multiple time points. To directly measure how drug resistance spreads within a host and to assess how spatial structure impacts its emergence, we examined serial sequences from four macaques infected with RT-SHIVmne027, a simian immunodeficiency virus encoding HIV-1 reverse transcriptase (RT), and treated with RT inhibitors. Both viral DNA and RNA (vDNA and vRNA) were isolated from the blood (including plasma and peripheral blood mononuclear cells), lymph nodes, gut, and vagina at a median of four time points and RT was characterized via single-genome sequencing. The resulting sequences reveal a dynamic system in which vRNA rapidly acquires drug resistance concomitantly across compartments through multiple independent mutations. Fast migration results in the same viral genotypes present across compartments, but not so fast as to equilibrate their frequencies immediately. The blood and lymph nodes were found to be compartmentalized rarely, while both the blood and lymph node were more frequently different from mucosal tissues. This study suggests that even oft-sampled blood does not fully capture the viral dynamics in other parts of the body, especially the gut where vRNA turnover was faster than the plasma and vDNA retained fewer wild-type viruses than other sampled compartments. Our findings of transient compartmentalization across multiple tissues may help explain the varied results of previous compartmentalization studies in HIV-1.

Application of nanotechnology for the development of microbicides.

The vaginal route is increasingly being considered for both local and systemic delivery of drugs, especially those unsuitable for oral administration. One of the opportunities offered by this route but yet to be fully utilised is the administration of microbicides. Microbicides have an unprecedented potential for mitigating the global burden from HIV infection as heterosexual contact accounts for most of the new infections occurring in sub-Saharan Africa, the region with the highest prevalent rates. Decades of efforts and massive investment of resources into developing an ideal microbicide have resulted in disappointing outcomes, as attested by several clinical trials assessing the suitability of those formulated so far. The highly complex and multi-level biochemical interactions that must occur among the virus, host cells and the drug for transmission to be halted means that a less sophisticated approach to formulating a microbicide e.g. conventional gels, etc may have to give way for a different formulation approach. Nanotechnology has been identified to offer prospects for fabricating structures with high capability of disrupting HIV transmission. In this review, predominant challenges seen in microbicide development have been highlighted and possible ways of surmounting them suggested. Furthermore, formulations utilising some of these highly promising nanostructures such as liposomes, nanofibres and nanoparticles have been discussed. A perspective on how a tripartite collaboration among governments and their agencies, the pharmaceutical industry and academic scientists to facilitate the development of an ideal microbicide in a timely manner has also been briefly deliberated.

Long-acting rilpivirine as potential pre-exposure prophylaxis for HIV-1 prevention (the MWRI-01 study): an open-label, phase 1, compartmental, pharmacokinetic and pharmacodynamic assessment.

BACKGROUND: Long-acting injectable antiretroviral agents are being developed for HIV-1 prevention. The MWRI-01 study was done to characterise the safety, acceptability, and pharmacokinetic and pharmacodynamic profile of long-acting rilpivirine. METHODS: We did a phase 1 open-label study at the University of Pittsburgh. We enrolled healthy individuals (aged 18-45 years) who were seronegative for HIV-1. Participants were assigned alternately one intramuscular dose of either 1200 mg or 600 mg long-acting rilpivirine, beginning with the 1200 mg dose. We obtained plasma specimens, genital and rectal fluids, and tissue samples (rectal, cervical, and vaginal) before and after exposure to long-acting rilpivirine for assessment of pharmacokinetics and ex-vivo biopsy challenge with HIV-1. Our primary objective was to characterise product safety, and the analysis included all enrolled participants. This trial is registered with ClinicalTrials.gov, number NCT01656018. FINDINGS: 36 participants were enrolled into the study, of whom 24 were women and 12 men. 12 women and six men received each dose. 204 adverse events were reported among the 36 participants, of which 200 (98%) were grade 1-2. The most common adverse event was injection site reaction. All grade 3 and 4 adverse events were deemed not related to rilpivirine. Geometric mean (90% CI) concentrations in plasma of rilpivirine at day 28 post dose were 53 ng/mL (38-67) in women and 43 ng/mL (23-63) in men for the 1200 mg dose and 28 ng/mL (19-37) in women and 17 ng/mL (9-24) in men for the 600 mg dose. The tissue-to-plasma ratio for rilpivirine in rectal tissue was about two-fold higher than in vaginal and cervical tissue (1·10-1·53 vs 0·61-0·72 and 0·50-0·71, respectively). Exposure to long-acting rilpivirine suppressed viral replication significantly in rectal tissue (p<0·0001), and this suppression persisted for up to 4 months. By contrast, no viral suppression was seen in cervical or vaginal tissue. INTERPRETATION: Ongoing research will characterise longer term safety and acceptability of multiple injections and help ascertain whether long-acting rilpivirine should advance to assessment of efficacy in preventing HIV-1 infection. FUNDING: Bill & Melinda Gates Foundation.

Evaluation of a new solid media specimen transport card for high risk HPV detection and cervical cancer prevention.

BACKGROUND: Solid media transport can be used to design adaptable cervical cancer screening programs but currently is limited by one card with published data. OBJECTIVE: To develop and evaluate a solid media transport card for use in high-risk human papillomavirus detection (HR-HPV). STUDY DESIGN: The Preventative Oncology International (POI) card was constructed using PK 226 paper(®) treated with cell-lysing solution and indicating dye. Vaginal samples were applied to the POI card and the indicating FTA (iFTA) elute card. A cervical sample was placed in liquid media. All specimens were tested for HR-HPV. Color change was assessed at sample application and at card processing. Stability of the POI card and iFTA elute card was tested at humidity. RESULTS: 319 women were enrolled. Twelve women had at least one insufficient sample with no difference between media (p=0.36). Compared to liquid samples, there was good agreement for HR-HPV detection with kappa of 0.81 (95% CI 0.74-0.88) and 0.71 (95% CI 0.62-0.79) for the POI and iFTA elute card respectively. Sensitivity for ≥CIN2 was 100% (CI 100-100%), 95.1% (CI 92.7-97.6%), and 93.5% (CI 90.7-96.3%) for the HR-HPV test from the liquid media, POI card, and iFTA elute card respectively. There was no color change of the POI card noted in humidity but the iFTA elute card changed color at 90% humidity. CONCLUSIONS: The POI card is suitable for DNA transport and HR-HPV testing. This card has the potential to make cervical cancer screening programs more affordable worldwide.

Interplay between the temporal dynamics of the vaginal microbiota and human papillomavirus detection.

BACKGROUND: We sought to describe the temporal relationship between vaginal microbiota and human papillomavirus (HPV) detection. METHODS: Thirty-two reproductive-age women self-collected midvaginal swabs twice weekly for 16 weeks (937 samples). Vaginal bacterial communities were characterized by pyrosequencing of barcoded 16S rRNA genes and clustered into 6 community state types (CSTs). Each swab was tested for 37 HPV types. The effects of CSTs on the rate of transition between HPV-negative and HPV-positive states were assessed using continuous-time Markov models. RESULTS: Participants had an average of 29 samples, with HPV point prevalence between 58%-77%. CST was associated with changes in HPV status (P<.001). Lactobacillus gasseri-dominated CSTs had the fastest HPV remission rate, and a low Lactobacillus community with high proportions of the genera Atopobium (CST IV-B) had the slowest rate compared to L. crispatus-dominated CSTs (adjusted transition rate ratio [aTRR], 4.43, 95% confidence interval [CI], 1.11-17.7; aTRR, 0.33, 95% CI, .12-1.19, respectively). The rate ratio of incident HPV for low Lactobacillus CST IV-A was 1.86 (95% CI, .52-6.74). CONCLUSIONS: Vaginal microbiota dominated by L. gasseri was associated with increased clearance of detectable HPV. Frequent longitudinal sampling is necessary for evaluation of the association between HPV detection and dynamic microbiota.

Optical coherence tomography for assessment of microbicide safety in a small animal model.

Sensitive imaging techniques for small animals are needed to assess drug toxicity in preclinical studies. Optical coherence tomography (OCT) provides a noninvasive tool for high-resolution, depth-resolved visualization of drug-induced changes in tissue morphology. In a mouse model, we utilize OCT to assess vaginal tissue integrity following the application of topical microbicides (drugs used to prevent infection). Mice are challenged with herpes simplex virus-2 (HSV-2) to determine the correlation of tissue damage as quantified by OCT to increased susceptibility. The microbicide benzalkonium chloride (BZK) (0.02, 0.2, or 2%) or phosphate buffered saline control is administered intravaginally. In vivo OCT imaging and collection of tissue samples are performed after treatment. A quantitative OCT scoring system is applied to assess epithelial damage, and the results are compared with those of histology. A separate group of mice are treated similarly then challenged with HSV-2. Epithelial morphology quantified noninvasively by OCT and histology are dose-dependent (p<0.0001). The OCT scoring system detected a significant increase in epithelial damage with increasing BZK concentration (p<0.0001). These results paralleled an increase in HSV-2 susceptibility (p<0.005). OCT can be used as a noninvasive tool to assess topical drug toxicity in a small animal model with potential to predict increased susceptibility to vaginal infection.

Longitudinal assessment of pigtailed macaque lower genital tract microbiota by pyrosequencing reveals dissimilarity to the genital microbiota of healthy humans.

Vaginal bacterial communities play an important role in human health and have been shown to influence HIV infection. Pigtailed macaques (Macaca nemestrina) are used as an animal model of HIV vaginal infection of women. Since the bacterial microbiota could influence retrovirus infection of pigtailed macaques, the genital microbiota in 10 cycling macaques was determined by pyrosequencing. The microbiota of all macaques was polymicrobial with a median of 13 distinct genera. Strikingly, the genera Sneathia and Fusobacterium, both in the phylum Fusobacteria, accounted for 18.9% and 13.3% of sequences while the next most frequent were Prevotella (5.6%), Porphyromonas (4.1%), Atopobium (3.6%), and Parvimonas (2.6%). Sequences corresponding to Lactobacillus comprised only 2.2% of sequences on average and were essentially all L. amylovorus. Longitudinal sampling of the 10 macaques over an 8-week period, which spanned at least one full ovulatory cycle, showed a generally stable presence of the major types of bacteria with some exceptions. These studies show that the microbiota of the pigtailed macaques is substantially dissimilar to that found in most healthy humans, where the genital microbiota is usually dominated by Lactobacillus sp. The polymicrobial makeup of the macaque bacterial populations, the paucity of lactobacilli, and the specific types of bacteria present suggest that the pigtailed macaque microbiota could influence vaginal retrovirus infection.

Advances in microbicide vaginal rings.

Vaginal ring devices capable of providing sustained/controlled release of incorporated actives are already marketed for steroidal contraception and estrogen replacement therapy. In recent years, there has been considerable interest in developing similar ring devices for the administration of microbicidal compounds to prevent vaginal HIV transmission. Intended to be worn continuously, such coitally independent microbicide rings are being developed to maintain effective vaginal microbicide concentrations over many weeks or months, thereby overcoming issues around timing of product application, user compliance and acceptability associated with more conventional semi-solid formulations. In this article, an overview of vaginal ring technologies is presented, followed by a review of recent advances and issues pertaining to their application for the delivery of HIV microbicides. This article forms part of a special supplement on presentations covering intravaginal rings, based on the symposium "Trends in Microbicide Formulations", held on 25 and 26 January 2010, Arlington, VA.

Novel approaches to vaginal delivery and safety of microbicides: biopharmaceuticals, nanoparticles, and vaccines.

The HIV-1 epidemic remains unchecked despite existing technology; vaccines and microbicides in development may help reverse the epidemic. Reverse transcriptase inhibitors (RTIs) formulated in gels tenofovir (TFV) and IVRs (dapivirine) are under clinical development. While TFV or similar products may prove successful for HIV-1, alternatives to RTIs may provide additional benefits, e.g., broader STI prevention. Biopharmaceutical agents under development as microbicides include cyanovirin, RANTES analogues, commensals, and Mabs. Cost of manufacturing biopharmaceuticals has been reduced and they can be formulated into tablets, films, and IVRs for vaginal delivery. Nanotechnology offers a novel approach to formulate microbicides potentially leading to uniform epithelial delivery. Delivery through vaginal mucus may be possible by controlling nanoparticle size and surface characteristics. Combining prevention modalities may be the most effective means of preventing STI transmission, importantly, codelivery of microbicides and vaccines has demonstrated. Finally, the safety of microbicide preparations and excipients commonly used can be assessed using a mouse/HSV-2 susceptibility model. Screening of new microbicide candidates and formulation excipients may avoid past issues of enhancing HIV-1 transmission. This article forms part of a special supplement covering several presentations on novel microbicide formulations from the symposium on "Recent Trends in Microbicide Formulations" held on 25 and 26 January 2010, Arlington, VA.

Accuracy and cost-effectiveness of cervical cancer screening by high-risk human papillomavirus DNA testing of self-collected vaginal samples.

OBJECTIVE: Estimate the accuracy and cost-effectiveness of cervical cancer screening strategies based on high-risk human papillomavirus (HPV) DNA testing of self-collected vaginal samples. MATERIALS AND METHODS: A subset of 1,665 women (age range, 18-50 y) participating in a cervical cancer screening study were screened by liquid-based cytology and by high-risk HPV DNA testing of both self-collected vaginal swab samples and clinician-collected cervical samples. Women with positive/abnormal screening test results and a subset of women with negative screening test results were triaged to colposcopy. On the basis of individual and combined test results, 5 screening strategies were defined. Estimates of sensitivity and specificity for cervical intraepithelial neoplasia grade 2 or worse were calculated, and a Markov model was used to estimate the incremental cost-effectiveness ratios for each strategy. RESULTS: Compared with cytology-based screening, high-risk HPV DNA testing of self-collected vaginal samples was more sensitive (68%, 95% CI = 58%-78% vs 85%, 95% CI = 76%-94%) but less specific (89%, 95% CI = 86%-91% vs 73%, 95% CI = 67%-79%). A strategy of high-risk HPV DNA testing of self-collected vaginal samples followed by cytology triage of HPV-positive women was comparably sensitive (75%, 95% CI = 64%-86%) and specific (88%, 95% CI = 85%-92%) to cytology-based screening. In-home self-collection for high-risk HPV DNA detection followed by in-clinic cytology triage had a slightly lower lifetime cost and a slightly higher quality-adjusted life year (QALY) expectancy than did cytology-based screening (incremental cost-effectiveness ratio of triennial screening compared with no screening was $9,871/QALY and $12,878/QALY, respectively). CONCLUSIONS: Triennial screening by high-risk HPV DNA testing of in-home, self-collected vaginal samples followed by in-clinic cytology triage was cost-effective.

Practical prevention of vaginal and rectal transmission of HIV by adapting the oral defense: use of commercial lubricants.

HIV is transmitted to 6.4 million human beings per year and the majority of these transmissions are sexual. Condoms are highly effective and are recommended as the primary preventive. However, the fact that there are millions of sexual transmissions each year indicates that many people do not use condoms and that additional preventives are needed. The mechanisms of natural prevention of oral transmission by saliva may be adaptable to the susceptible vagina and rectum. The objective of our study was to reduce the sexual transmission of HIV by mimicking saliva's targeting of the transmitting infected leukocytes and any cell-free HIV in seminal fluid. The previously recommended anti-HIV topical microbicide, nonoxynol-9, has not prevented HIV transmission in humans, probably because it causes mucosal irritation and attracts CD4(+) cells. To identify effective preparations that are nonirritating, we studied the anti-HIV activity of commercially available, over-the-counter (OTC) lubricants and vaginal preparations that are judged safest by the U.S. Food and Drug Administration (FDA), and are nonirritating. The effect of OTC preparations on both the production of HIV by infected leukocytes and cell-free HIV suspended in seminal fluid was measured under simulated in vivo conditions. We surveyed 22 OTC vaginal preparations and excluded those with low inhibitory activity and those that were inhibitory but likely to be irritating. Three included preparations are highly active against both HIV-infected leukocytes suspended in seminal fluid and active against cell-free HIV, under in vitro conditions that simulate in vivo conditions. Since the preparations identified here as anti-HIV substances have the advantages of being widely available, inexpensive, acceptable, in the safest U.S. FDA category, and may be used by recipient women or men, they should be tested in clinical trials to help prevent sexual transmission of HIV.

Ethical challenges in efficacy trials of vaginal microbicides for HIV prevention.

This paper discusses some of the ethical challenges raised by advanced clinical trials designed to assess the safety and efficacy of vaginal microbicides in protecting women from HIV infection. The ethical principles that guide clinical research involving human subjects require that all participants in such trials be provided available measures known to reduce the risk of HIV infection. However, this will reduce the ability of the study to assess the protective effect of the test microbicide. In addition, providing extensive services to trial participants may be construed as an undue inducement if the study is being conducted among vulnerable groups such as sex workers or women from disadvantaged communities. Suggestions are provided to resolve this dilemma in the planning and implementation of HIV prevention services for trial participants.