Bernardo Vega Crespo

Dr. Bernardo Vega Crespo

Salud Sexual y Reproductiva, Universidad de Cuenca, Cuenca, Azuay, Ecuador
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Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 November 2022 in BMC Public Health
Verified
Journal Article
Open access
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Bernardo Vega CrespoBernardo Vega Crespo
Bernardo Vega Crespo
VNVivian Alejandra Neira
Vivian Alejandra Neira
JSJosé Ortiz S
José Ortiz S
AAAndrés Andrade
Andrés Andrade
GAGabriela Guerra Astudillo
Gabriela Guerra Astudillo
ODOlivier Degomme
Olivier Degomme
Background: Cervical cancer screening is a cost-effective method responsible for reducing cervical cancer-related mortality by 70% in countries that have achieved high coverage through nationwide screening strategies. However, there are disparities in access to screening. In Ecuador, although cervical cancer is the second most common cancer in women, only 58.4% of women of reproductive age have ever been screened for cervical cancer. Methodology: A qualitative study was performed to understand the current barriers to screening and to identify strategies that could increase uptake in Azuay province, Ecuador. Seven focus group discussions (FGDs) were conducted with under-screened women and health professionals (HPs). The FGDs were recorded and transcribed. Content analysis was done using the socio-ecological framework to categorize and analyse the data. Results: Overall, 28 women and 27 HPs participated in the study. The two groups perceived different barriers to cervical cancer screening. The HPs considered barriers to be mainly at the policy level (lack of a structured screening plan; lack of health promotion) and the individual level (lack of risk perception; personal beliefs). The women identified barriers mainly at organizational level, such as long waiting times, lack of access to health centres, and inadequate patient–physician communication. Both groups mentioned facilitators at policy level, such as national campaigns promoting cervical cancer screening, and at community and individual level, including health literacy and women’s empowerment. Conclusions: The women considered access to health services the main barrier to screening, while the HPs identified a lack of investment in screening programmes and cultural patterns at the community level as major obstacles. To take an integrated approach to cervical cancer prevention, the perspectives of both groups should be taken into account. Additionally, new strategies and technologies, such as self-administered human papillomavirus (HPV) testing and community participation, should be implemented to increase access to cervical cancer screening.

27 January 2024 in Biology
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PRPedro Rosendo-Chalma
Pedro Rosendo-Chalma
VAVERÓNICA ANTONIO-VÉJAR
VERÓNICA ANTONIO-VÉJAR
JOJonnathan Gerardo Ortiz
Jonnathan Gerardo Ortiz
JSJosé Ortiz S
José Ortiz S
Bernardo Vega CrespoBernardo Vega Crespo
Bernardo Vega Crespo
GOGabriele Davide Bigoni Ordóñez
Gabriele Davide Bigoni Ordóñez
Human papillomaviruses (HPVs) and, specifically, high-risk HPVs (HR-HPVs) are identified as necessary factors in the development of cancer of the lower genital tract, with CaCU standing out as the most prevalent tumor. This review summarizes ten mechanisms activated by HR-HPVs during cervical carcinogenesis, which are broadly associated with at least seven of the fourteen distinctive physiological capacities of cancer in the newly established model by Hanahan in 2022. These mechanisms involve infection by human papillomavirus, cellular tropism, genetic predisposition to uterine cervical cancer (CaCU), viral load, viral physical state, regulation of epigenetic mechanisms, loss of function of the E2 protein, deregulated expression of E6/E7 oncogenes, regulation of host cell protein function, and acquisition of the mesenchymal phenotype.

1 October 2016 in Evaluation and Program Planning
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Journal Article
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OIOlena Ivanova
Olena Ivanova
Kathya Lorena Cordova-PozoKathya Lorena Cordova-Pozo
Kathya Lorena Cordova-Pozo
ZSZoyla Esmeralda Segura
Zoyla Esmeralda Segura
Bernardo Vega CrespoBernardo Vega Crespo
Bernardo Vega Crespo
VCVenkatraman Chandra-Mouli
Venkatraman Chandra-Mouli
KMKristien Michielsen
Kristien Michielsen
The Community-Embedded Reproductive Health Care for Adolescents (CERCA) Project was implemented in Bolivia, Ecuador and Nicaragua (2011-2014) to test the effectiveness of interventions preventing teenage pregnancies. As the outcome evaluation showed limited impact, a post-hoc process evaluation was carried out to determine if and how CERCA's design, implementation, monitoring and evaluation affected the results. We did a document analysis and conducted 18 in-depth interviews and 21 focus group discussions with stakeholders and beneficiaries. Transcripts were analyzed using directed content analysis. Data showed that CERCA sensitized stakeholders and encouraged the discussion on this sensitive issue. In terms of design, a strong point was the participatory approach; a weak point was that the detailed situation analysis was completed too late. In terms of implementation, a strong point was that multifaceted activities were implemented; a weak point was that the activities were not pilot tested for feasibility/acceptability and evolved substantially throughout the Project. In terms of monitoring, strong points were that regular monitoring kept the Project on track administratively/financially; a weak point was that monitoring indicators did not change as the intervention package changed. In terms of evaluation, weak points were the substantial attrition rate and narrow focus on adolescents. This study provides recommendations for future projects.

12 July 2022 in Diagnostics
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Yuliana Jiménez GaonaYuliana Jiménez Gaona
Yuliana Jiménez Gaona
Darwin Castillo MallaDarwin Castillo Malla
Darwin Castillo Malla
Bernardo Vega CrespoBernardo Vega Crespo
Bernardo Vega Crespo
MVMaría José Vicuña
María José Vicuña
VNVivian Alejandra Neira
Vivian Alejandra Neira
VVveronique verhoeven
veronique verhoeven
Background: Colposcopy imaging is widely used to diagnose, treat and follow-up on premalignant and malignant lesions in the vulva, vagina, and cervix. Thus, deep learning algorithms are being used widely in cervical cancer diagnosis tools. In this study, we developed and preliminarily validated a model based on the Unet network plus SVM to classify cervical lesions on colposcopy images. Methodology: Two sets of images were used: the Intel & Mobile ODT Cervical Cancer Screening public dataset, and a private dataset from a public hospital in Ecuador during a routine colposcopy, after the application of acetic acid and lugol. For the latter, the corresponding clinical information was collected, specifically cytology on the PAP smear and the screening of human papillomavirus testing, prior to colposcopy. The lesions of the cervix or regions of interest were segmented and classified by the Unet and the SVM model, respectively. Results: The CAD system was evaluated for the ability to predict the risk of cervical cancer. The lesion segmentation metric results indicate a DICE of 50%, a precision of 65%, and an accuracy of 80%. The classification results’ sensitivity, specificity, and accuracy were 70%, 48.8%, and 58%, respectively. Randomly, 20 images were selected and sent to 13 expert colposcopists for a statistical comparison between visual evaluation experts and the CAD tool (p-value of 0.597). Conclusion: The CAD system needs to improve but could be acceptable in an environment where women have limited access to clinicians for the diagnosis, follow-up, and treatment of cervical cancer; better performance is possible through the exploration of other deep learning methods with larger datasets.

Bernardo Vega CrespoBernardo Vega Crespo
Bernardo Vega Crespo
VNVivian Alejandra Neira
Vivian Alejandra Neira
JSJosé Ortiz S
José Ortiz S
RMRuth Elizabeth Maldonado-Rengel
Ruth Elizabeth Maldonado-Rengel
DLDiana López
Diana López
VVveronique verhoeven
veronique verhoeven
Background: HPV primary screening has shown effectiveness for cancer prevention; however, gynaecological examination is considered uncomfortable. Self-sampling methods increase the acceptance of screening. The aim of this study is to compare the sensitivity and specificity of clinician sampling versus vaginal and urine self-sampling for HPV diagnosis. Methods: A diagnostic test study was conducted in a rural parish of Cuenca, Ecuador. A total of 120 women participated. Each participant self-collected urine and vaginal samples and underwent clinician sampling for HPV testing. The latter was considered as the golden standard. All three samples were processed with the same amplification and hybridization protocol for HPV detection (Hybribio) following the manufacturer’s instructions. Results: Characteristics of the participants were: median age 35 years; 40.8% married; 46.7% had a primary level of education; and median age of sexual onset, 17.6 years. The prevalence of any type of HPV with clinician sampling was 15.0%, 17.5% with urine sampling and 18.3% with vaginal self-sampling. Self-sampling sensitivity reached 94.4% (IC 74.2–99.9), and specificity 92.1% (IC 85.2–95.9). Urine sampling had a sensitivity of 88.8% (IC 67.2, 96.9), and specificity 94.1% (IC 67.2–96.9). The negative predictive value was 98.9% (IC 94.2–99.8) for vaginal self-sampling and 97.6% (IC 92.6–99.4) for urine sampling. Conclusions: This study shows that vaginal and urine self-sampling methods have similar sensitivity and specificity compared with clinician sampling for the diagnosis of HPV. The correlation between HPV genotypes among the three tests is satisfactory.

31 July 2020 in BMC International Health and Human Rights
Verified
Journal Article
Open access
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KPKatrina Perehudoff
Katrina Perehudoff
HVHeleen Vermandere
Heleen Vermandere
AWAlex Williams
Alex Williams
SBSergio Bautista-Arredondo
Sergio Bautista-Arredondo
EPElien De Paepe
Elien De Paepe
ODOlivier Degomme
Olivier Degomme
Background: Cervical cancer claims 311,000 lives annually, and 90% of these deaths occur in low- and middle-income countries. Cervical cancer is a highly preventable and treatable disease, if detected through screening at an early stage. Governments have a responsibility to screen women for precancerous cervical lesions. Yet, national screening programmes overlook many poor women and those marginalised in society. Under-screened women (called hard-to-reach) experience a higher incidence of cervical cancer and elevated mortality rates compared to regularly-screened women. Such inequalities deprive hard-to-reach women of the full enjoyment of their right to sexual and reproductive health, as laid out in Article 12 of the International Covenant on Economic, Social and Cultural Rights and General Comment No. 22. Discussion: This article argues first for tailored and innovative national cervical cancer screening programmes (NCSP) grounded in human rights law, to close the disparity between women who are afforded screening and those who are not. Second, acknowledging socioeconomic disparities requires governments to adopt and refine universal cancer control through NCSPs aligned with human rights duties, including to reach all eligible women. Commonly reported- and chronically under-addressed- screening disparities relate to the availability of sufficient health facilities and human resources (example from Kenya), the physical accessibility of health services for rural and remote populations (example from Brazil), and the accessibility of information sensitive to cultural, ethnic, and linguistic barriers (example from Ecuador). Third, governments can adopt new technologies to overcome individual and structural barriers to cervical cancer screening. National cervical cancer screening programmes should tailor screening methods to under-screened women, bearing in mind that eliminating systemic discrimination may require committing greater resources to traditionally neglected groups. Conclusion: Governments have human rights obligations to refocus screening policies and programmes on women who are disproportionately affected by discrimination that impairs their full enjoyment of the right to sexual and reproductive health. National cervical cancer screening programmes that keep the right to health principles (above) central will be able to expand screening among low-income, isolated and other marginalised populations, but also women in general, who, for a variety of reasons, do not visit healthcare providers for regular screenings.