Vaccine effectiveness against COVID-19 hospitalisation in adults (≥ 20 years) during Alpha- and Delta-dominant circulation: I-MOVE-COVID-19 and VEBIS SARI VE networks, Europe, 2021

Members of the I-MOVE-COVID-19 and VEBIS hospital study teams (in addition to the named authors): Svjetlana Karabuva, Petra Tomaš Petrić, Marija Marković, Sandra Ljubičić, Bojana Mahmutović, Irena Tabain, Petra Smoljo, Iva Pem Novosel, Tanya Melillo, John Paul Cauchi, Benédicte Lissoir, Xavier Holemans, Marc Hainaut, Nicolas Dauby, Benedicte Delaere, Marc Bourgeois, Evelyn Petit, Marijke Reynders, Door Jouck, Koen Magerman, Marieke Bleyen, Melissa Vermeulen, Sébastien Fierens, François Dufrasne, Siel Daelemans, Ala’a Al Kerwi, Francoise Berthet, Guy Fagherazzi, Myriam Alexandre, Charlene Bennett, Jim Christle, Jeff Connell, Peter Doran, Laura Feeney, Binita Maharjan, Sinead McDermott, Rosa McNamara, Nadra Nurdin, Salif Mamadou Cissé, Anne-Sophie L'Honneur, Xavier Duval, Yolande Costa, Fidouh Nadhira, Florence Galtier, Laura Crantelle, Vincent Foulongne, Phillipe Vanhems, Sélilah Amour, Bruno Lina, Fabrice Lainé, Laetitia Gallais, Gisèle Lagathu, Anna Maisa, Yacine Saidi, Christine Durier, Rebecca Bauer, Ana Paula Rodrigues, Adriana Silva, Raquel Guiomar, Margarida Tavares, Débora Pereira, Maria José Manata, Heidi Gruner, André Almeida, Paula Pinto, Cristina Bárbara, Itziar Casado, Ana Miqueleiz, Ana Navascués, Camino Trobajo-Sanmartín, Miguel Fernández-Huerta, María Eugenia Portillo, Carmen Ezpeleta, Nerea Egüés, Manuel García Cenoz, Eva Ardanaz, Marcela Guevara, Conchi Moreno-Iribas, Hana Orlíková, Carmen Mihaela Dorobat, Carmen Manciuc, Simin Aysel Florescu, Alexandru Marin, Sorin Dinu, Catalina Pascu, Alina Ivanciuc, Iulia Bistriceanu, Mihaela Oprea, Maria Elena Mihai, Silke Buda, Ute Preuss, Marianne Wedde, Auksė Mickienė, Giedrė Gefenaitė, Alain Moren, Anthony NardoneIntroduction: Two large multicentre European hospital networks have estimated vaccine effectiveness (VE) against COVID-19 since 2021. Aim: We aimed to measure VE against PCR-confirmed SARS-CoV-2 in hospitalised severe acute respiratory illness (SARI) patients ≥ 20 years, combining data from these networks during Alpha (March–June)- and Delta (June–December)-dominant periods, 2021. Methods: Forty-six participating hospitals across 14 countries follow a similar generic protocol using the test-negative case–control design. We defined complete primary series vaccination (PSV) as two doses of a two-dose or one of a single-dose vaccine ≥ 14 days before onset. Results: We included 1,087 cases (538 controls) and 1,669 cases (1,442 controls) in the Alpha- and Delta-dominant periods, respectively. During the Alpha period, VE against hospitalisation with SARS-CoV2 for complete Comirnaty PSV was 85% (95% CI: 69–92) overall and 75% (95% CI: 42–90) in those aged ≥ 80 years. During the Delta period, among SARI patients ≥ 20 years with symptom onset ≥ 150 days from last PSV dose, VE for complete Comirnaty PSV was 54% (95% CI: 18–74). Among those receiving Comirnaty PSV and mRNA booster (any product) ≥ 150 days after last PSV dose, VE was 91% (95% CI: 57–98). In time-since-vaccination analysis, complete all-product PSV VE was > 90% in those with their last dose < 90 days before onset; ≥ 70% in those 90–179 days before onset. Conclusions: Our results from this EU multi-country hospital setting showed that VE for complete PSV alone was higher in the Alpha- than the Delta-dominant period, and addition of a first booster dose during the latter period increased VE to over 90%.Key public health message: - What did you want to address in this study? To understand how well the COVID-19 vaccine was performing in Europe against hospitalisation during SARS-CoV-2 Alpha and Delta variant periods, we present vaccine effectiveness results from a multi-country study of complete and booster dose COVID-19 vaccination among adults (aged 20 years and over). - What have we learnt from this study? Between March and June 2021 (Alpha period), vaccine effectiveness against hospitalisation with laboratory-confirmed SARS-CoV-2 was 43% for partial vaccination and 86% for complete vaccination. For June to December 2021 (Delta period), vaccine effectiveness for complete vaccination was lower (52%) but with addition of an mRNA booster dose, effectiveness reached 91%, and remained > 90% up to 119 days after the booster dose. - What are the implications of your findings for public health? In Europe in 2021, COVID-19 vaccine effectiveness results for the Alpha period indicated an excellent benefit for preventing hospitalisation after complete vaccination. During Delta variant circulation, however, a booster dose was required to achieve this level of effectiveness, and this was maintained for up to 4 months post booster.info:eu-repo/semantics/publishedVersio

Vaccine effectiveness against COVID-19 hospitalisation in adults (≥ 20 years) during Omicron-dominant circulation: I-MOVE-COVID-19 and VEBIS SARI VE networks, Europe, 2021 to 2022

Introduction: The I-MOVE-COVID-19 and VEBIS hospital networks have been measuring COVID-19 vaccine effectiveness (VE) in participating European countries since early 2021. Aim: We aimed to measure VE against PCR-confirmed SARS-CoV-2 in patients ≥ 20 years hospitalised with severe acute respiratory infection (SARI) from December 2021 to July 2022 (Omicron-dominant period). Methods: In both networks, 46 hospitals (13 countries) follow a similar test-negative case-control protocol. We defined complete primary series vaccination (PSV) and first booster dose vaccination as last dose of either vaccine received ≥ 14 days before symptom onset (stratifying first booster into received < 150 and ≥ 150 days after last PSV dose). We measured VE overall, by vaccine category/product, age group and time since first mRNA booster dose, adjusting by site as a fixed effect, and by swab date, age, sex, and presence/absence of at least one commonly collected chronic condition. Results: We included 2,779 cases and 2,362 controls. The VE of all vaccine products combined against hospitalisation for laboratory-confirmed SARS-CoV-2 was 43% (95% CI: 29-54) for complete PSV (with last dose received ≥ 150 days before onset), while it was 59% (95% CI: 51-66) after addition of one booster dose. The VE was 85% (95% CI: 78-89), 70% (95% CI: 61-77) and 36% (95% CI: 17-51) for those with onset 14-59 days, 60-119 days and 120-179 days after booster vaccination, respectively. Conclusions: Our results suggest that, during the Omicron period, observed VE against SARI hospitalisation improved with first mRNA booster dose, particularly for those having symptom onset < 120 days after first booster dose.Key public health message: 1. What did you want to address in this study? In order to understand how well the COVID-19 vaccine is performing in Europe against hospitalisation during the period when the SARS-CoV-2 Omicron variant was circulating, we investigated vaccine effectiveness using data from a multi-country study of complete and booster-dose COVID-19 vaccination among adults aged 20 years and over. 2. What have we learnt from this study? Between December 2021 and July 2022, vaccine effectiveness against hospitalisation with laboratory-confirmed SARS-CoV-2 was 43% for complete vaccination. With addition of an mRNA booster dose, effectiveness was 59% overall. It was higher when onset of illness was close to the date of the last vaccination, at 85% when last booster dose was 14–59 days before onset, at 70% for 60–119 days, and falling below 40% for 120–179 days. 3. What are the implications of your findings for public health? In European hospital settings in 2022, during the Omicron period, COVID-19 mRNA booster vaccine provided an improved benefit for preventing hospitalisation, particularly if disease onset was within 4 months of receiving the booster dose.info:eu-repo/semantics/publishedVersio

COVID-19 Vaccines against Omicron Variant: Real-World Data on Effectiveness

The efficacy of vaccines against coronavirus disease 2019 (COVID-19) has now been well established in phase III clinical trials. However, clinical studies based on real-world data remain critical to assess vaccines effectiveness (VE), especially in specific populations and against variants of concern (VOC). This review presents the principles and methods of VE studies and the main available results on VE of COVID-19 vaccines at the time of Omicron circulation. References for this narrative review were identified through searches of PubMed database up to 13 September 2022. The results of phase III clinical trials have been globally confirmed by VE in real-life studies, including in the elderly. Emergence of VOC Omicron emphasized the importance of booster doses to maintain a high level of protection against severe forms. There are still numerous challenges regarding booster(s) and duration of immunity, particularly in specific subpopulations, and regarding the need for adapted vaccines

Modelling human-to-human transmission of monkeypox

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Performance of two simplified HBV treatment criteria (TREAT-B score and WHO guidelines) in Burkina Faso, West Africa

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Immunological and clinical efficacy of COVID-19 vaccines in immunocompromised populations: a systematic review

International audienceBackground: Available data show that COVID-19 vaccines may be less effective in immunocompromised populations, who are at increased risk of severe COVID-19.Objectives: We conducted a systematic review of literature to assess immunogenicity, efficacy and effectiveness of COVID-19 vaccines in immunocompromised populations.Data sources: We searched Medline and Embase databases.Study eligibility criteria, patients, interventions: We included studies of COVID-19 vaccines after complete vaccination in immunocompromised patients until 31 August 2021. Studies with <10 patients, safety data only and case series of breakthrough infections were excluded.Methods: Risk of bias was assessed via the tool developed by the National Institutes of Health on interventional and observational studies. Immunogenicity was assessed through non-response rate defined as no anti-SARS-CoV-2 spike protein antibodies, efficacy and effectiveness by the relative reduction in risk of SARS-CoV-2 infection or COVID-19. We collected factors associated with the risk of non-response. We presented collected data by immunosuppression type.Results: We screened 5917 results, included 162 studies. There were 157 on immunogenicity in 25 209 participants, including 7835 cancer or haematological malignancy patients (31.1%), 6302 patients on dialysis (25.0%), 5974 solid organ transplant recipients (23.7%) and 4680 immune-mediated disease patients (18.6%). Proportion of non-responders seemed higher among solid organ transplant recipients (range 18-100%) and patients with haematological malignancy (range 14-61%), and lower in patients with cancer (range 2-36%) and patients on dialysis (range 2-30%). Risk factors for non-response included older age, use of corticosteroids, immunosuppressive or anti-CD20 agent. Ten studies evaluated immunogenicity of an additional dose. Five studies evaluated vaccine efficacy or effectiveness: three on SARS-CoV-2 infection (range 71-81%), one on COVID-19-related hospitalization (62.9%), one had a too small sample size.Conclusions: This systematic review highlights the risk of low immunogenicity of COVID-19 vaccines in immunocompromised populations, especially solid organ transplant recipients and patients with haematological malignancy. Despite lack of vaccine effectiveness data, enhanced vaccine regimens may be necessary

Recurrent Bordetella holmesii Bacteremia and Nasal Carriage in a Patient Receiving Rituximab

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A national platform for Covid-19 vaccine studies recruitment in France: Covireivac volunteer’s characteristics

During the Covid-19 pandemic, the urgent need for safe and effective vaccines has led to many vaccine trials, implying fast and extensive recruitment of volunteers. In France, until 2020, vaccine clinical research participants were usually recruited locally, through center-based pools of volunteers, and local communication plans. Covireivac is a French public online platform launched on 10/01/2020 that enables national, large-scale recruitment of volunteers for Covid-19 vaccine studies. On the Covireivac website, all adult participants registered online, gave their informed consent, and filled out two online forms with information on their identity, health status (comorbidities, treatments), and known exposure to SARS-CoV-2. Since July 2021, volunteers could mention if their children are interested in participating in a Covid-19 vaccine trial. The objective of this work is to describe Covireivac's volunteer characteristics registered from 10/01/2020 to 11/02/2022. To identify independent volunteer characteristics associated with a period of registration we performed a multivariate logistic regression. Among 54,424 registrations, 52,391 (96%) were analysed; 61% were male (n = 31,893), median age was 50 y; 13% (n = 6586) were healthcare workers. At registration, 15,879 volunteers (33%) reported at least one comorbidity, among whom 16% (n = 7349) were obese and 17% (n = 8346) had hypertension. Most volunteers registered during the first month (n = 35,876, 66%). The Covireivac platform allowed quick and large recruitment of potential volunteers for Covid-19 vaccine trials and could be used on a larger scale for vaccine trials in France. It could facilitate recruitment in vaccine trials and provide sponsors with better visibility of the recruitment capacities of clinical research centers

Vaccine effectiveness against COVID-19 hospitalization in adults in France: A test negative case control study

International audienceBACKGROUND: Measuring vaccine effectiveness (VE) using real-life data is critical to confirm the effectiveness of licensed vaccine, which could strengthen vaccination adherence. METHODS: We measured VE against adult COVID-19 hospitalization in five hospitals in France using a test negative design. We compared the odds of vaccinated patients hospitalized with COVID-19 with the odds of vaccinated patients hospitalized for the same symptoms with a negative test. RESULTS: A total of 853 patients (463 cases and 390 controls) were included, with a total of 170 patients vaccinated (104 with one dose, 65 with two doses, and one with three doses). There were four cases of breakthrough infections, all in immunocompromised patients. The VE was 84.0% (CI(0.95)=[72.6; 90.6]) for one dose and 96.2% (CI(0.95)=[86.8; 98.9]) for two doses. CONCLUSION: Our results confirm the high VE of COVID-19 vaccine in France to prevent hospitalizations due to the alpha variant

First case of Elizabethkingia anophelis meningitis in the Central African Republic.

International audienceAn 8-day-old girl of indigenous origin delivered by caesarean section to an HIV-negative mother with an uneventful pregnancy presented to the Complexe Pédiatrique in Bangui, Central African Republic, in March 2011 with a 3-day history of fever at 38.5 °C. The newborn had a history of intubation and mechanical ventilation at birth due to asphyxia, followed by 2 days of hospitalization. At admission, she was irritable, feeding poorly, had a seizure and had lost 1500 g (32%) of her birth weight. She showed ..