Pooling for SARS-CoV-2 control in care institutions.

BACKGROUND: Workers and residents in Care Homes are considered at special risk for the acquisition of SARS-CoV-2 infection, due to the infectivity and high mortality rate in the case of residents, compared to other containment areas. The role of presymptomatic people in transmission has been shown to be important and the early detection of these people is critical for the control of new outbreaks. Pooling strategies have proven to preserve SARS-CoV-2 testing resources. The aims of the present study, based in our local experience, were (a) to describe SARS-CoV-2 prevalence in institutionalized people in Galicia (Spain) during the Coronavirus pandemic and (b) to evaluate the expected performance of a pooling strategy using RT-PCR for the next rounds of screening of institutionalized people. METHODS: A total of 25,386 Nasopharyngeal swab samples from the total of the residents and workers at Care Homes in Galicia (March to May 2020) were individually tested using RT-PCR. Prevalence and quantification cycle (Cq) value distribution of positives was calculated. Besides, 26 pools of 20 samples and 14 pools of 5 samples were tested using RT-PCR as well (1 positive/pool). Pooling proof of concept was performed in two populations with 1.7 and 2% prevalence. RESULTS: Distribution of SARS-CoV-2 infection at Care Homes was uneven (0-60%). As the virus circulation global rate was low in our area (3.32%), the number of people at risk of acquiring the infection continues to be very high. In this work, we have successfully demonstrated that pooling of different groups of samples at low prevalence clusters, can be done with a small average delay on Cq values (5 and 2.85 cycles for pools of 20 and 5 samples, respectively). CONCLUSIONS: A new screening system with guaranteed protection is required for small clusters, previously covered with individual testing. Our proposal for Care Homes, once prevalence zero is achieved, would include successive rounds of testing using a pooling solution for transmission control preserving testing resources. Scale-up of this method may be of utility to confront larger clusters to avoid the viral circulation and keeping them operative.

Cervical intraepithelial neoplasia grade 2 or worse in Galicia, Spain: HPV 16 prevalence and vaccination impact / Neoplasia intraepitelial cervical de grado 2 o peor en Galicia (España): prevalencia de HPV 16 e impacto vacunal

INTRODUCTION: The etiology of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) can influence the efficacy of Public Health preventive strategies. This study aimed to determine the high-risk papillomavirus (HR-HPV) prevalence in CIN2+ cases in unvaccinated women in Galicia (Spain), the expected impact of bivalent vaccination, and the distribution of HPV 16 in squamous lesions. MATERIAL AND METHODS: Ninety-four histologically confirmed cases of CIN2+ (2009-2010) were retrospectively studied: 23 CIN2, 58 CIN3− squamous carcinoma in situ (CIN3-CIS), 5 adenocarcinoma in situ (AIS), and 8 invasive squamous cervical cancer (SCC). Linear Array HPV Genotyping Test (Roche Diagnostics, Mannheim, Germany) was performed on the cervical specimens. Bivalent vaccination impact was calculated, based on regional vaccination coverage data, local HR-HPV prevalence, and reported efficacy (direct and cross-protection) of the vaccine. RESULTS: HR-HPV prevalence was 96.8%. The most frequent genotypes were HPV 16 (48.8-58.2%) and HPV 31 (9.3%-12.1%), considering single infections or single-multiple infections, respectively (hierarchical attribution). In squamous lesions, HPV 16 prevalence in women younger than 45 years of age increased in severe lesions (CIN3-CIS/SCC, OR 4.2), and was higher than in older women (OR 5.5). The vaccine could reduce the cumulative incidence of CIN2+ by 50.6% (direct protection), or by 62.7% (direct and cross-protection). CONCLUSION: HPV vaccination could have a great impact in women younger than 45 years of age due to the high prevalence of HPV 16 in their lesions

INTRODUCCIÓN: La etiología de la neoplasia intraepitelial cervical de grado 2 o peor (CIN2+) influirá en la eficacia de las estrategias preventivas de Salud Pública. Se pretende conocer la prevalencia de papilomavirus de alto riesgo (VPH-AR) en CIN2+ en mujeres no vacunadas en Galicia (España), el impacto esperado de la vacunación bivalente y la distribución del VPH 16 en lesiones escamosas. MATERIAL Y MÉTODOS: Se estudiaron retrospectivamente 94 casos confirmados histológicamente de CIN2+ (2009-2010): 23 CIN2, 58 CIN3- carcinoma escamoso in situ (CIN3-CIS), 5 adenocarcinoma in situ (AIS) y 8 carcinoma escamoso invasivo (CES). Se utilizó Linear Array VPH Genotyping Test (Roche Diagnostics, Mannheim, Alemania) en muestras cervicales. El impacto de la vacunación se calculó según la cobertura vacunal autonómica, la prevalencia local de VPH-AR y datos publicados de eficacia (protección directa y cruzada). RESULTADOS: La prevalencia de VPH-AR fue del 96,8%. Los genotipos más frecuentes fueron HPV 16 (48,8-58,2%) y HPV 31 (9,3-12,1%) considerando infecciones simples o infecciones simples-múltiples, respectivamente (atribución jerárquica). En lesiones escamosas, la prevalencia de VPH 16 en mujeres de hasta 45 años aumentó con la severidad de las lesiones (CIN3-CIS/CES; OR 4,2) y fue mayor que en las mujeres mayores (OR 5,5). La vacuna podría reducir la incidencia acumulada de CIN2+ un 50,6% (protección directa) o un 62,7% (protección directa y cruzada). CONCLUSIÓN: La vacunación frente al VPH podría tener un gran impacto en mujeres menores de 45 años debido a la alta prevalencia de VPH 16 en las lesiones que presentan

Cervical intraepithelial neoplasia grade 2 or worse in Galicia, Spain: HPV 16 prevalence and vaccination impact.

INTRODUCTION: The etiology of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) can influence the efficacy of Public Health preventive strategies. This study aimed to determine the high-risk papillomavirus (HR-HPV) prevalence in CIN2+ cases in unvaccinated women in Galicia (Spain), the expected impact of bivalent vaccination, and the distribution of HPV 16 in squamous lesions. MATERIAL AND METHODS: Ninety-four histologically confirmed cases of CIN2+ (2009-2010) were retrospectively studied: 23 CIN2, 58 CIN3- squamous carcinoma in situ (CIN3-CIS), 5 adenocarcinoma in situ (AIS), and 8 invasive squamous cervical cancer (SCC). Linear Array HPV Genotyping Test (Roche Diagnostics, Mannheim, Germany) was performed on the cervical specimens. Bivalent vaccination impact was calculated, based on regional vaccination coverage data, local HR-HPV prevalence, and reported efficacy (direct and cross-protection) of the vaccine. RESULTS: HR-HPV prevalence was 96.8%. The most frequent genotypes were HPV 16 (48.8-58.2%) and HPV 31 (9.3%-12.1%), considering single infections or single-multiple infections, respectively (hierarchical attribution). In squamous lesions, HPV 16 prevalence in women younger than 45 years of age increased in severe lesions (CIN3-CIS/SCC, OR 4.2), and was higher than in older women (OR 5.5). The vaccine could reduce the cumulative incidence of CIN2+ by 50.6% (direct protection), or by 62.7% (direct and cross-protection). CONCLUSION: HPV vaccination could have a great impact in women younger than 45 years of age due to the high prevalence of HPV 16 in their lesions.

Human papillomavirus (HPV) E6/E7 mRNA as a triage test after detection of HPV 16 and HPV 18 DNA.

High-risk human papillomavirus (HPV) DNA detection provides high sensitivity but low specificity for moderate-grade cervical intraepithelial neoplasia or worse histological identification. A prospective study evaluated mRNA testing efficacy for predicting this histological diagnosis in case of HPV 16 and/or 18 DNA detection. A total of 165 endocervical samples harboring HPV 16 and/or 18 DNA were tested with NucliSENS-EasyQ® HPV E6/E7-mRNA-assay (Biomerieux, Marcy l´Etoile, France). Women with cytological alterations were referred to colposcopy (n = 111). Moderate-grade cervical intraepithelial neoplasia or worse was diagnosed in 25.8% of women presenting atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesions and in 89.8% of women with high-grade squamous intraepithelial lesions. mRNA sensitivity was 81.3% and 84.1%, respectively. Specificity was 52.2%, and 80.0%, respectively. Negative predictive value (NPV) was 88.9% in undetermined or low-grade squamous lesions. Positive predictive value (PPV) was 97.4% in high-grade squamous lesions. mRNA reduced colposcopies by 44.3% in undetermined or low-grade squamous lesions. Direct treatment of mRNA-positive cases reduced 77.5% of colposcopies in high-grade squamous lesions. Women without cytological alterations were followed for 18 months (n = 35), and moderate-grade cervical intraepithelial neoplasia or worse was diagnosed in 34.3%; mRNA sensitivity and specificity were 83.3% and 86.9%, respectively. PPV and NPV were 76.9% and 90.9%, respectively for predicting moderate-grade cervical intraepithelial neoplasia or worse in 18 months. mRNA reduced the number of visits for follow-up in 62.2%. In conclusion, NucliSENS-EasyQ® HPV E6/E7-mRNA-assay (Biomerieux) can serve as a triage test in case of HPV 16 and/or 18 DNA detection.