Nirsevimab Effectiveness Against Cases of Respiratory Syncytial Virus Bronchiolitis Hospitalised in Paediatric Intensive Care Units in France, September 2023-January 2024.

In September 2023, France was one of the first countries that started a national immunisation campaign with nirsevimab, a new monoclonal antibody against respiratory syncytial virus (RSV). Using data from a network of paediatric intensive care units (PICUs), we aimed to estimate nirsevimab effectiveness against severe cases of RSV bronchiolitis in France. We conducted a case-control study based on the test-negative design and included 288 infants reported by 20 PICUs. We estimated nirsevimab effectiveness at 75.9% (48.5-88.7) in the main analysis and 80.6% (61.6-90.3) and 80.4% (61.7-89.9) in two sensitivity analyses. These real-world estimates confirmed the efficacy observed in clinical studies.

Acceptability of vaginal self-sampling with high-risk human papillomavirus testing for cervical cancer screening: a French questionnaire-based study.

In France, cervical cancer screening based on cervical smear has a participation rate of around 60%. New screening strategies are encouraged to increase the participation of under-screened women, including vaginal self-sampling with high-risk human papillomavirus (HR-HPV) testing. This study was based on the distribution of an anonymous self-administered questionnaire to assess the acceptability of vaginal self-sampling with HR-HPV testing by women aged 25 to 65 years in two French Departments of the South of France, Aude, and Hérault, showing low participation in cervical cancer screening. Factors influencing this acceptability were also analyzed. From May to July 2017, 349 completed questionnaires were collected. Women declared high acceptability for vaginal self-sampling (81%) preferably at home (82.6%). Acceptability was statistically higher in the Department of Herault (p = .001) and for women older than 50 years (p = .018). There was no difference according to educational level or attendance to cervical cancer screening. Knowledge about cervical cancer and cervical cancer screening was significantly influenced by educational level. This study confirmed that vaginal self-sampling with HR-HPV testing was highly accepted, including by under-screened women, encouraging further interventional studies. Education about cervical cancer and cervical cancer screening should be part of these programs, especially for women with lower educational level.

Intensive care unit surveillance of influenza infection in France: the 2009/10 pandemic and the three subsequent seasons.

During the 2009/10 pandemic, a national surveillance system for severe influenza cases was set up in France. We present results from the system's first four years. All severe influenza cases admitted to intensive care units (ICU) were reported to the Institut de Veille Sanitaire using a standardised form: data on demographics, immunisation and virological status, risk factors, severity (e.g. acute respiratory distress syndrome (ARDS) onset, mechanical ventilation, extracorporeal life support) and outcome. Multivariate analysis was performed to identify factors associated with ARDS and death. The number of confirmed influenza cases varied from 1,210 in 2009/10 to 321 in 2011/12. Most ICU patients were infected with A(H1N1)pdm09, except during the 2011/12 winter season when A(H3N2)-related infections predominated. Patients' characteristics varied according to the predominant strain. Based on multivariate analysis, risk factors associated with death were age ≥ 65 years, patients with any of the usual recommended indications for vaccination and clinical severity. ARDS occurred more frequently in patients who were middle-aged (36-55 years), pregnant, obese, or infected with A(H1N1)pdm09. Female sex and influenza vaccination were protective. These data confirm the persistent virulence of A(H1N1)pdm09 after the pandemic and the heterogeneity of influenza seasons, and reinforce the need for surveillance of severe influenza cases.

Timely detection of bronchiolitis epidemics in Guadeloupe.

OBJECTIVE: To develop a criterion for early detection of bronchiolitis epidemics in Guadeloupe so that prevention and control strategies can be implemented in a more timely manner. METHODS: Weekly figures of bronchiolitis cases reported from July 2005-July 2010 by Guadeloupe's sentinel network were used. The criterion for detecting epidemics was created with data from the 2005-2009 bronchiolitis seasons. First, the baseline level for bronchiolitis (BL) was predicted by fitting a periodic regression on the non-epidemic observations; then a test was conducted of nine possible criteria to define epidemics by combining a statistical threshold set at different levels and a number of consecutive weeks with observations above and below them; lastly, the optimal criterion was selected considering its performances using expert advice as the gold standard. The selected criterion was validated with data from 2009-2010 season. RESULTS: The BL accounted for a linear trend and two sinusoidal functions of 52 and 26 weeks (R2 = 45%). According to the epidemic criterion selected, the statistical threshold was set at the upper limit of the one-sided 95% Confidence Interval of the predicted BL; 2 consecutive weeks with cases above it were necessary to set the start of an epidemic, and three again below to set the end. The median delay in launching the alerts was 2 weeks; there was one false alert; and the sensitivity, specificity, and positive predictive value for detecting epidemic weeks were 98%, 96%, 95%, respectively. During the validation period, the criterion launched one false alert and detected the epidemic with 4 weeks of delay. CONCLUSIONS: This criterion supports epidemiologists in timely interpretation of bronchiolitis epidemiological data for decision makers in Guadeloupe. In the future, it should be updated in accordance with trends in bronchiolitis epidemiology, and improved by integrating virological indicators. Its inclusion in an integrated management strategy for bronchiolitis prevention and control, supported by a bronchiolitis public health network, should also be encouraged.

Hospitalized cases of influenza A(H1N1)pdm09 in the French territories of the Americas, July 2009-March 2010.

OBJECTIVE: To describe the methodology used for implementing a surveillance system specifically for influenza A(H1N1)pdm09 in the French West Indies and French Guiana during an outbreak of this new virus in 2009-2010, and to report its main results. METHODS: This was an observational descriptive study of confirmed and probable cases of influenza A(H1N1)pdm09 hospitalized for at least 24 hours in 23 July 2009-3 March 2010. Reverse transcription polymerase chain reaction was performed on nasopharyngeal swab samples according to the Centers for Disease Control and Prevention protocol. A probable case was defined as fever > 38ºC or aches or asthenia with respiratory symptoms (cough or dyspnea). All confirmed and probable hospitalized cases were reported, along with patient's age, sex, clinical condition at admission, place and length of hospitalization, antiviral treatment, underlying conditions, complications, and clinical evolution. A case was classified as severe if respiratory assistance or intensive care was required or if death resulted. RESULTS: A total of 331 confirmed and 16 probable cases were hospitalized, with a hospitalization rate ranging from 4.3 per 1 000 clinical cases in Saint Martin to 10.3 in French Guiana. Of these, 36 were severe, and subsequently, 10 were fatal. The median length of stay was 4 days for non-severe cases and 9 days for severe (P < 0.05). The mean patient age was 21 years, and severe cases were significantly older than non-severe (mean: 38 years versus 19 years, P < 0.05). Underlying conditions associated with a higher risk of severity were 65 years of age or more (RR = 7.5, 95%CI = 4.2-13.3), diabetes (RR = 3.7, 95%CI = 1.5-9.4), cardiac insufficiency (RR = 8.4, 95%CI = 5.2-13.6), and morbid obesity (RR = 4.4, 95%CI = 1.8-10.4). Patients who received antiviral treatment within 2 days of symptom onset had shorter hospital stays (mean: 4 days versus 6.5 days, P < 0.05), and the illness tended to become less severe (11.1% versus 19.0%, P = 0.13). CONCLUSIONS: Active research of hospitalized cases enabled almost exhaustive surveillance. The pandemic's hospitalization rates and lethality were more moderate than expected. Some previously known underlying conditions of severity were confirmed during this outbreak. Furthermore, these results show the validity of early antiviral treatment.

Timely detection of bronchiolitis epidemics in Guadeloupe / Detección oportuna de epidemias de bronquiolitis en Guadalupe

Objective. To develop a criterion for early detection of bronchiolitis epidemics in Guadeloupe so that prevention and control strategies can be implemented in a more timely manner. Methods. Weekly figures of bronchiolitis cases reported from July 2005­July 2010 by Guadeloupe's sentinel network were used. The criterion for detecting epidemics was created with data from the 2005­2009 bronchiolitis seasons. First, the baseline level for bronchiolitis (BL) was predicted by fitting a periodic regression on the non-epidemic observations; then a test was conducted of nine possible criteria to define epidemics by combining a statistical threshold set at different levels and a number of consecutive weeks with observations above and below them; lastly, the optimal criterion was selected considering its performances using expert advice as the gold standard. The selected criterion was validated with data from 2009­2010 season. Results. The BL accounted for a linear trend and two sinusoidal functions of 52 and 26 weeks (R2 = 45%). According to the epidemic criterion selected, the statistical threshold was set at the upper limit of the one-sided 95% Confidence Interval of the predicted BL; 2 consecutive weeks with cases above it were necessary to set the start of an epidemic, and three again below to set the end. The median delay in launching the alerts was 2 weeks; there was one false alert; and the sensitivity, specificity, and positive predictive value for detecting epidemic weeks were 98%, 96%, 95%, respectively. During the validation period, the criterion launched one false alert and detected the epidemic with 4 weeks of delay. Conclusions. This criterion supports epidemiologists in timely interpretation of bronchiolitis epidemiological data for decision makers in Guadeloupe. In the future, it should be updated in accordance with trends in bronchiolitis epidemiology, and improved by integrating virological indicators. Its inclusion in an integrated management strategy for bronchiolitis prevention and control, supported by a bronchiolitis public health network, should also be encouraged.

Objetivo. Formular un criterio para la detección temprana de las epidemias de bronquiolitis en Guadalupe, a fin de aplicar de manera más oportuna mejores estrategias de prevención y control. Métodos. Se usaron las cifras semanales de los casos de bronquiolitis notificados desde julio del 2005 hasta julio del 2010 por la red de vigilancia de Guadalupe. El criterio para detectar las epidemias se estableció con los datos de las temporadas de bronquiolitis del 2005 al 2009. En primer lugar, se predijo el nivel basal de bronquiolitis ajustando una regresión periódica a los casos observados fuera de las epidemias; luego se pusieron a prueba nueve posibles criterios para definir las epidemias combinando un umbral estadístico establecido a diferentes niveles y un número de semanas consecutivas con las observaciones ubicadas por encima y por debajo de ellos; por último, se seleccionó el criterio óptimo conforme a su desempeño, usando el asesoramiento de expertos como criterio de referencia. El criterio seleccionado se validó con los datos de la temporada 2009­2010. Resultados. El nivel basal de bronquiolitis presentaba una tendencia lineal y dos funciones sinusoidales de 52 y 26 semanas (R2 = 45%). Según el criterio de epidemia seleccionado, se fijó el umbral estadístico en el límite superior del intervalo de confianza de 95% unilateral del nivel basal de bronquiolitis previsto; para establecer el comienzo de una epidemia se requerían 2 semanas consecutivas con casos por encima de él, y 3 semanas con casos por debajo para determinar su finalización. La mediana del retraso para lanzar las alertas fue 2 semanas; hubo una alerta falsa; y la sensibilidad, la especificidad y el valor predictivo positivo para detectar las semanas de epidemia fueron 98%, 96% y 95%, respectivamente. Durante el período de validación se emitió, según el criterio, una alerta falsa y se detectó la epidemia con 4 semanas de retraso. Conclusiones. Este criterio ayuda a los epidemiólogos a interpretar de manera oportuna los datos epidemiológicos de bronquiolitis a fin de tomar decisiones en Guadalupe. En el futuro, debe actualizarse según las tendencias en la epidemiología de la bronquiolitis, y mejorarse mediante su integración con indicadores virológicos. También debe promoverse su inclusión en una estrategia integrada de manejo para la prevención y el control de la bronquiolitis, apoyada por una red de salud pública relacionada con la bronquiolitis

Hospitalized cases of influenza A(H1N1)pdm09 in the French territories of the Americas, July 2009–March 2010 / Casos hospitalizados de gripe A(H1N1)pdm09 en los territorios franceses de las Américas entre julio de 2009 y marzo de 2010

Objective. To describe the methodology used for implementing a surveillance system specifically for influenza A(H1N1)pdm09 in the French West Indies and French Guiana during an outbreak of this new virus in 2009­2010, and to report its main results. Methods. This was an observational descriptive study of confirmed and probable cases of influenza A(H1N1)pdm09 hospitalized for at least 24 hours in 23 July 2009­3 March 2010. Reverse transcription polymerase chain reaction was performed on nasopharyngeal swab samples according to the Centers for Disease Control and Prevention protocol. A probable case was defined as fever ≥ 38°C or aches or asthenia with respiratory symptoms (cough or dyspnea). All confirmed and probable hospitalized cases were reported, along with patient's age, sex, clinical condition at admission, place and length of hospitalization, antiviral treatment, underlying conditions, complications, and clinical evolution. A case was classified as severe if respiratory assistance or intensive care was required or if death resulted. Results. A total of 331 confirmed and 16 probable cases were hospitalized, with a hospitalization rate ranging from 4.3 per 1 000 clinical cases in Saint Martin to 10.3 in French Guiana. Of these, 36 were severe, and subsequently, 10 were fatal. The median length of stay was 4 days for non-severe cases and 9 days for severe (P < 0.05). The mean patient age was 21 years, and severe cases were significantly older than non-severe (mean: 38 years versus 19 years, P < 0.05). Underlying conditions associated with a higher risk of severity were 65 years of age or more (RR = 7.5, 95%CI = 4.2­13.3), diabetes (RR = 3.7, 95%CI = 1.5­9.4), cardiac insufficiency (RR = 8.4, 95%CI = 5.2­13.6), and morbid obesity (RR = 4.4, 95%CI = 1.8­ 10.4). Patients who received antiviral treatment within 2 days of symptom onset had shorter hospital stays (mean: 4 days versus 6.5 days, P < 0.05), and the illness tended to become less severe (11.1% versus 19.0%, P = 0.13). Conclusions. Active research of hospitalized cases enabled almost exhaustive surveillance. The pandemic's hospitalization rates and lethality were more moderate than expected. Some previously known underlying conditions of severity were confirmed dur.

Objetivo. Describir la metodología usada para implementar un sistema de vigilancia específico para la gripe A(H1N1)pdm09 en las Indias Occidentales Francesas y la Guayana Francesa durante un brote ocasionado por este virus nuevo ocurrido en 20092010 y presentar sus principales resultados. Métodos. Se llevó a cabo un estudio de observación descriptivo de los casos confirmados y probables de gripe por A(H1N1)pdm09 hospitalizados durante al menos 24 horas entre el 23 de julio de 2009 y el 3 de marzo de 2010. De conformidad con el protocolo de los Centros para el Control y la Prevención de Enfermedades se realizó la prueba de reacción en cadena de la polimerasa con transcripción inversa en muestras de hisopados nasofaríngeos. Se definió como caso probable la presencia de fiebre ≥ 38 °C o dolores o astenia junto con síntomas respiratorios (tos o disnea). Se comunicaron todos los casos hospitalizados confirmados y probables junto con la edad, el sexo, la situación clínica del paciente en el momento del ingreso, el lugar y la duración de la hospitalización, el tratamiento antivírico, las enfermedades subyacentes, las complicaciones y la evolución clínica. Se clasificaron como graves los casos que requirieron asistencia respiratoria o cuidados intensivos o provocaron la muerte. Resultados. Fueron hospitalizados en total 331 casos confirmados y 16 probables, con una tasa de hospitalización que osciló entre 4,3 por cada 1 000 casos clínicos en San Martín y 10,3 por cada 1 000 en la Guayana Francesa. De ellos, 36 fueron graves y 10 llevaron posteriormente a la muerte del paciente. La mediana de la duración de las hospitalizaciones fue de 4 días para los casos no graves y de 9 días para los graves (P < 0,05). La edad media de los pacientes fue de 21 años, y los casos graves fueron significativamente de mayor edad que los no graves (media: 38 años frente a 19 años; P < 0,05). Las enfermedades subyacentes asociadas con un riesgo mayor de gravedad fueron edad de 65 años o más (RR = 7,5; IC de 95% = 4,213,3), diabetes (RR = 3,7; IC de 95% = 1,59,4), insuficiencia cardíaca (RR = 8,4; IC de 95% = 5,213,6) y obesidad mórbida (RR = 4,4; IC de 95% = 1,810,4). En los pacientes que recibieron tratamiento antivírico en el plazo de 2 días de la aparición de los síntomas las estancias hospitalarias fueron más breves (media: 4 días frente a 6,5 días; P < 0,05) y la enfermedad tendió a presentar menor gravedad (11,1% frente a 19,0%; P = 0,13). Conclusiones. La investigación activa de los casos hospitalizados permitió una vigilancia casi exhaustiva. Las tasas de hospitalización y la letalidad de la pandemia fueron más moderadas que lo previsto. Durante este brote se confirmó la capacidad de algunas enfermedades subyacentes ya conocidas para aumentar la gravedad. Además, estos resultados demuestran la validez del tratamiento antivírico temprano

Virological surveillance of dengue in Saint Martin and Saint Barthelemy, French West Indies, using blood samples on filter paper.

To strengthen active dengue surveillance in Saint Martin and Saint Barthélemy, two French Caribbean islands, we evaluated the epidemiological usefulness of collecting blood samples from NS1-positive dengue patients on filter paper to identify the dengue serotypes circulating in these regions during a 27-month period. This approach allowed dengue serotypes to be identified by reverse transcriptase-polymerase chain reaction in 90.1% of the total set of 666 samples analyzed and, in 95.5% of the samples collected during the acute phase of the disease. This prospective virological surveillance using blood samples absorbed onto filter paper, which were stored at 4°C and shipped at ambient temperature to a specialized laboratory for analysis, allowed us to avoid the logistic and financial costs associated with shipping frozen venous blood samples. This surveillance system offers a low-cost alternative for reinforcing dengue prevention in areas where specialized laboratories do not exist, notably by facilitating the early detection of potentially new dengue serotypes.