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Valcarcel Salamanca B, Cyr PR, Bentdal YE, Watle SV, Wester AL, Strand ÅMW, Bøås H. Increase in invasive group A streptococcal infections (iGAS) in children and older adults, Norway, 2022 to 2024. Euro Surveill 2024; 29:2400242. [PMID: 38757285 PMCID: PMC11100296 DOI: 10.2807/1560-7917.es.2024.29.20.2400242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Accepted: 05/16/2024] [Indexed: 05/18/2024] Open
Abstract
At the end of 2022 and most notably during the first half of 2023, the number of invasive group A streptococcus (iGAS) notifications increased in Norway, largely affecting children younger than 10 years, as observed in several other countries. Following this atypical season, a new surge in the number of iGAS notifications began in December 2023 and peaked between January and February 2024, now particularly affecting both children younger than 10 years and older adults (70 years and above).
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Affiliation(s)
- Beatriz Valcarcel Salamanca
- ECDC Fellowship Programme, Field Epidemiology path (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Pascale Renée Cyr
- Department of Infectious Disease Registries, Norwegian Institute of Public Health, Oslo, Norway
| | - Yngvild Emblem Bentdal
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Sara Viksmoen Watle
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | | | - Åse Marie Wikman Strand
- Department of Infectious Disease Registries, Norwegian Institute of Public Health, Oslo, Norway
| | - Håkon Bøås
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
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Watle SV, Børud B, Laake I, Baranowska-Hustad M, Bryant-Bratlie D, Bekkevold T, Caugant DA, Tunheim G, Næss LM. Antibodies against Neisseria meningitidis serogroups A, C, W and Y in serum and saliva of Norwegian adolescents. Vaccine 2023; 41:6529-6537. [PMID: 37648606 DOI: 10.1016/j.vaccine.2023.08.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/18/2023] [Accepted: 08/21/2023] [Indexed: 09/01/2023]
Abstract
INTRODUCTION The incidence of invasive meningococcal disease (IMD) among Norwegian 16-19-year-olds was 1-7/100,000 in the decade before the COVID-19 pandemic, with serogroup Y (MenY) dominance. In contrast to many other European countries, meningococcal vaccines are not part of the national immunisation program (NIP) in Norway. This cross-sectional study aimed to measure the degree of natural immunity against Neisseria meningitidis among adolescents in Norway to evaluate the need for introducing tetravalent meningococcal conjugate vaccine (MCV4) in the NIP. MATERIALS AND METHODS Serum and saliva samples were collected from students in upper and lower secondary schools in Norway in 2018. Samples were analysed for meningococcal capsular polysaccharide (PS)-specific antibodies using a bead-based multiplex immunoassay. PS-specific antibody levels were linked to data on meningococcal carriage, vaccination status and risk factors for carriage (assessed with questionnaire) and analysed by linear regression of log transformed concentrations. A subset of samples from unvaccinated individuals was analysed for serum bactericidal antibodies (SBA). RESULTS A total of 1344 participants, median age 16 years (range 12-24), were included in the study. Overall, 60.9% of the participants were female and 1137 (84.6%) were not vaccinated with MCV4. PS-specific antibody concentrations in serum and saliva were low among unvaccinated individuals for all serogroups and only 6.7-20.0% of the subpopulation with high PS-specific antibodies assessed with SBA had protective levels. Unvaccinated MenY carriers had higher levels of MenY anti-PS IgG in serum and IgA in saliva than those not carrying MenY. Use of Swedish snus was associated with lower anti-PS IgG levels in serum and waterpipe use with lower anti-PS IgG levels in saliva. CONCLUSION Unvaccinated adolescents in Norway have a low degree of natural immunity against the serogroups of N. meningitidis predominating among cases of IMD in this age group. Therefore, introduction of MCV4 for adolescents in the NIP is recommended.
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Affiliation(s)
- Sara Viksmoen Watle
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway; Institute of Health and Society, Faculty of Medicine, University of Oslo, P.O. Box 1078, Blindern, 0316 Oslo, Norway.
| | - Bente Børud
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
| | - Ida Laake
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
| | - Marta Baranowska-Hustad
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
| | - Diane Bryant-Bratlie
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
| | - Terese Bekkevold
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
| | - Dominique A Caugant
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway; Institute of Health and Society, Faculty of Medicine, University of Oslo, P.O. Box 1078, Blindern, 0316 Oslo, Norway
| | - Gro Tunheim
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
| | - Lisbeth Meyer Næss
- Division of Infection Control, Norwegian Institute of Public Health, P.O. Box 222, Skøyen, 0213 Oslo, Norway
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Orangzeb S, Watle SV, Caugant DA. Adherence to vaccination guidelines of patients with complete splenectomy in Norway, 2008-2020. Vaccine 2023:S0264-410X(23)00699-0. [PMID: 37336662 DOI: 10.1016/j.vaccine.2023.06.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/21/2023]
Abstract
The spleen is responsible for blood filtration and mounting an immune response against pathogens. In some people the spleen must be surgically removed because of traumatic events or oncological and hematological conditions. These patients are at higher risk of developing diseases caused by encapsulated bacteria throughout their lives. Thus, immunisations are advised for splenectomised persons to prevent infection caused by Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae type b (Hib). This study assessed vaccination coverage (VC) among Norwegian patients with surgical asplenia. Using the Nomesco Classification of Surgical Procedures codes, patient information (age, sex, date of initial diagnosis and date of surgery) was acquired from the Norwegian Patient Registry. The National Immunization Register provided information on vaccination status and data of any subsequent invasive bacterial infections were obtained from the Norwegian Surveillance System for Communicable Diseases. From the total population of Norway, 3155 patients who had undergone complete splenectomy were identified. Of these, 914 (29.0%) had received at least one dose of pneumococcal conjugate vaccine (PCV), 1324 (42.0%) at least one dose of pneumococcal polysaccharide vaccine and 589 (18.7%) had received both. Only 4.2% of the patients had received two doses of a meningococcal ACWY conjugate vaccine, while 8.0% of 1467 patients splenectomised after 2014 had received at least two doses of a serogroup B meningococcal vaccine. The VC for Hib was 18.7%. Nearly all splenectomised children under the age of 10 were vaccinated with Hib and PCV as these vaccines are included in the childhood immunisation program. For all vaccines, VC decreased with age. Twenty-nine invasive bacterial infections were registered post-splenectomy in 25 patients. Vaccination according to national recommendations could have prevented at least 8 (28%) of these infections. Our study showed that efforts are required to increase VC of splenectomised individuals in Norway.
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Affiliation(s)
- Saima Orangzeb
- Department of Community Medicine and Global Health, Faculty of Medicine, University of Oslo, Oslo, Norway; Division for Infection Control, Norwegian Institute of Public Health, Oslo, Norway
| | - Sara Viksmoen Watle
- Department of Community Medicine and Global Health, Faculty of Medicine, University of Oslo, Oslo, Norway; Division for Infection Control, Norwegian Institute of Public Health, Oslo, Norway
| | - Dominique A Caugant
- Department of Community Medicine and Global Health, Faculty of Medicine, University of Oslo, Oslo, Norway; Division for Infection Control, Norwegian Institute of Public Health, Oslo, Norway.
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Brynildsrud OB, Watle SV, Alfsnes K, Caugant DA. Invasive meningococcal disease in Norway in the two decades prior to the COVID-19 pandemic. Int J Infect Dis 2023; 131:130-139. [PMID: 37030654 DOI: 10.1016/j.ijid.2023.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/24/2023] [Accepted: 04/03/2023] [Indexed: 04/09/2023] Open
Abstract
OBJECTIVES Disease caused by the bacterium Neisseria meningitidis remains a global public health challenge, despite steadily decreasing incidence in Western countries. The objective of this study was to explore the epidemiology of invasive meningococcal disease in Norway over the last two decades. DESIGN All isolates sent to the National Reference Laboratory from patients with invasive meningococcal disease between the years 2000 and 2019 were analyzed using whole genome sequencing, total 625. RESULTS A five-fold decrease in case numbers occurred over this period, and the situation has gone from being dominated by serogroup B to one where serogroups Y and W are more prevalent. Concurrently, the mean age at infection has increased from 18 to 33 years. Among the 350 serogroup B isolates, 87% were exact match or cross-reactive with one or both of the currently available serogroup B vaccines, but the proportion decreased in the past decade. Core genome analyses revealed high variation in the number of allelic differences accumulated in epidemiologically linked isolates, to the point that near-identical isolates were found several years apart. CONCLUSION Allelic distance is an imprecise metric for the degree of epidemiologic linkage between isolates in N. meningitidis.
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Veneti L, Berild JD, Watle SV, Starrfelt J, Greve-Isdahl M, Langlete P, Bøås H, Bragstad K, Hungnes O, Meijerink H. Effectiveness of BNT162b2 vaccine against SARS-CoV-2 Delta and Omicron infection in adolescents, Norway, August 2021 to January 2022. Int J Infect Dis 2023; 130:182-188. [PMID: 36893942 PMCID: PMC9991321 DOI: 10.1016/j.ijid.2023.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023] Open
Abstract
OBJECTIVES We estimated the BNT162b2 vaccine effectiveness (VE) against any (symptomatic or not) SARS-CoV-2 Delta and Omicron infection among adolescents (12-17-years-old) in Norway from August 2021 to January 2022. METHODS We used Cox proportional hazard models, where vaccine status was included as a time-varying covariate and models were adjusted for age, sex, comorbidities, residence county, birth country, and living conditions. RESULTS VE against Delta infection peaked at 68% (95%CI:64-71%) and 62% (95%CI:57-66%) in days 21-48 after the first dose among 12-15-year-olds and 16-17-year-olds respectively. Among 16-17-year-olds that received two doses, VE against Delta infection peaked at 93% (95%CI:90-95%) in days 35-62 and decreased to 84% (95%CI:76-89%) in ≥63 days after vaccination. We did not observe a protective effect against Omicron infection after receiving one dose. Among 16-17-year-olds, VE against Omicron infection peaked at 53% (95%CI:43-62%) in 7-34 days after the second dose and decreased to 23% (95%CI:3-40%) in ≥63 days after vaccination. CONCLUSIONS We found reduced protection after two BNT162b2 vaccine doses against any Omicron infection compared to Delta. Effectiveness decreased with time from vaccination for both variants. The impact of vaccination among adolescents on reducing infection and thus transmission is limited during Omicron dominance.
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Affiliation(s)
- Lamprini Veneti
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway.
| | - Jacob Dag Berild
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Sara Viksmoen Watle
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Jostein Starrfelt
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Margrethe Greve-Isdahl
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Petter Langlete
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Håkon Bøås
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Karoline Bragstad
- Department of Virology, Norwegian Institute of Public Health, Oslo, Norway
| | - Olav Hungnes
- Department of Virology, Norwegian Institute of Public Health, Oslo, Norway
| | - Hinta Meijerink
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
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Lopez-Doriga Ruiz P, Gunnes N, Michael Gran J, Karlstad Ø, Selmer R, Dahl J, Bøås H, Aubrey White R, Christine Hofman A, Hessevik Paulsen T, Viksmoen Watle S, Hylen Ranhoff A, Bukholm G, Løvdal Gulseth H, Tapia G. Short-term safety of COVID-19 mRNA vaccines with respect to all-cause mortality in the older population in Norway. Vaccine 2023; 41:323-332. [PMID: 36376216 PMCID: PMC9637531 DOI: 10.1016/j.vaccine.2022.10.085] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 10/13/2022] [Accepted: 10/31/2022] [Indexed: 11/09/2022]
Abstract
BACKGROUND There have been concerns about COVID-19 vaccination safety among frail older individuals. We investigated the relationship between COVID-19 mRNA vaccination and mortality among individuals aged ≥ 70 years and whether mortality varies across four groups of health services used. METHODS In this nationwide cohort study, we included 688,152 individuals aged ≥ 70 years at the start of the Norwegian vaccination campaign (December 27, 2020). We collected individual-level data from theNorwegian Emergency Preparedness Register for COVID-19. Vaccinated and unvaccinated individuals were matched (1:1 ratio) on the date of vaccination based on sociodemographic and clinical characteristics. The main outcome was all-cause mortality during 21 days after first dose of COVID-19 mRNA vaccination. Kaplan-Meier survival functions were estimated for the vaccinated and unvaccinated groups. We used Cox proportional-hazards regression to estimate hazard ratios (HRs) of death between vaccinated and unvaccinated individuals, with associated 95% confidence intervals (CIs), overall and by use of health services (none, home-based, short- and long-term nursing homes) and age group. RESULTS Between December 27, 2020, and March 31, 2021, 420,771 older individuals (61.1%) were vaccinated against COVID-19. The Kaplan-Meier estimates based on the matched study sample showed a small absolute risk difference in all-cause mortality between vaccinated and unvaccinated individuals, with a lower mortality in the vaccinated group (overall HR 0.28 [95% CI: 0.24-0.31]). Similar results were obtained in analyses stratified by use of health services and age group. CONCLUSION We found no evidence of increased short-term mortality among vaccinated individuals in the older population after matching on sociodemographic and clinical characteristics affecting vaccination and mortality.
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Affiliation(s)
- Paz Lopez-Doriga Ruiz
- Norwegian Institute of Public Health, Oslo, Norway; Oslo University Hospital, Oslo, Norway.
| | - Nina Gunnes
- Norwegian Institute of Public Health, Oslo, Norway; Oslo University Hospital, Oslo, Norway
| | - Jon Michael Gran
- Oslo Centre for Biostatistics and Epidemiology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | | | - Randi Selmer
- Norwegian Institute of Public Health, Oslo, Norway
| | - Jesper Dahl
- Norwegian Institute of Public Health, Oslo, Norway
| | - Håkon Bøås
- Norwegian Institute of Public Health, Oslo, Norway
| | | | | | | | | | - Anette Hylen Ranhoff
- Norwegian Institute of Public Health, Oslo, Norway; Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Geir Bukholm
- Norwegian Institute of Public Health, Oslo, Norway
| | | | - German Tapia
- Norwegian Institute of Public Health, Oslo, Norway
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Starrfelt J, Danielsen AS, Buanes EA, Juvet LK, Lyngstad TM, Rø GØI, Veneti L, Watle SV, Meijerink H. Age and product dependent vaccine effectiveness against SARS-CoV-2 infection and hospitalisation among adults in Norway: a national cohort study, July-November 2021. BMC Med 2022; 20:278. [PMID: 36050718 PMCID: PMC9436448 DOI: 10.1186/s12916-022-02480-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 07/14/2022] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND COVID-19 vaccines have been crucial in the pandemic response and understanding changes in vaccines effectiveness is essential to guide vaccine policies. Although the Delta variant is no longer dominant, understanding vaccine effectiveness properties will provide essential knowledge to comprehend the development of the pandemic and estimate potential changes over time. METHODS In this population-based cohort study, we estimated the vaccine effectiveness of Comirnaty (Pfizer/BioNTech; BNT162b2), Spikevax (Moderna; mRNA-1273), Vaxzevria (AstraZeneca; ChAdOx nCoV-19; AZD1222), or a combination against SARS-CoV-2 infections, hospitalisations, intensive care admissions, and death using Cox proportional hazard models, across different vaccine product regimens and age groups, between 15 July and 31 November 2021 (Delta variant period). Vaccine status is included as a time-varying covariate and all models were adjusted for age, sex, comorbidities, county of residence, country of birth, and living conditions. Data from the entire adult Norwegian population were collated from the National Preparedness Register for COVID-19 (Beredt C19). RESULTS The overall adjusted vaccine effectiveness against infection decreased from 81.3% (confidence interval (CI): 80.7 to 81.9) in the first 2 to 9 weeks after receiving a second dose to 8.6% (CI: 4.0 to 13.1) after more than 33 weeks, compared to 98.6% (CI: 97.5 to 99.2) and 66.6% (CI: 57.9 to 73.6) against hospitalisation respectively. After the third dose (booster), the effectiveness was 75.9% (CI: 73.4 to 78.1) against infection and 95.0% (CI: 92.6 to 96.6) against hospitalisation. Spikevax or a combination of mRNA products provided the highest protection, but the vaccine effectiveness decreased with time since vaccination for all vaccine regimens. CONCLUSIONS Even though the vaccine effectiveness against infection waned over time, all vaccine regimens remained effective against hospitalisation after the second vaccine dose. For all vaccine regimens, a booster facilitated recovery of effectiveness. The results from this support the use of heterologous schedules, increasing flexibility in vaccination policy.
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Affiliation(s)
- Jostein Starrfelt
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Postboks 222 Skøyen, 0213, Oslo, Norway.
| | - Anders Skyrud Danielsen
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Postboks 222 Skøyen, 0213, Oslo, Norway.,Department of Microbiology, Oslo University Hospital, Oslo, Norway
| | - Eirik Alnes Buanes
- Norwegian Intensive Care and Pandemic Registry (NIPaR), Helse Bergen Health Trust, Bergen, Norway.,Department of Anaesthesiology and Intensive Care Haukeland University Hospital, Bergen, Norway
| | - Lene Kristine Juvet
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Trude Marie Lyngstad
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Postboks 222 Skøyen, 0213, Oslo, Norway
| | | | - Lamprini Veneti
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Postboks 222 Skøyen, 0213, Oslo, Norway
| | - Sara Viksmoen Watle
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Hinta Meijerink
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
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Whittaker R, Bråthen Kristofferson A, Valcarcel Salamanca B, Seppälä E, Golestani K, Kvåle R, Watle SV, Buanes EA. Length of hospital stay and risk of intensive care admission and in-hospital death among COVID-19 patients in Norway: a register-based cohort study comparing patients fully vaccinated with an mRNA vaccine to unvaccinated patients. Clin Microbiol Infect 2022; 28:871-878. [PMID: 35219807 PMCID: PMC8872711 DOI: 10.1016/j.cmi.2022.01.033] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/11/2022] [Accepted: 01/24/2022] [Indexed: 12/16/2022]
Abstract
OBJECTIVES We estimated the length of stay (LoS) in hospital and the intensive care unit (ICU) and risk of admission to ICU and in-hospital death among COVID-19 patients ≥18 years in Norway who had been fully vaccinated with an mRNA vaccine (at least two doses or one dose and previous SARS-CoV-2 infection), compared to unvaccinated patients. METHODS Using national registry data, we analyzed SARS-CoV-2-positive patients hospitalized in Norway between 1 February and 30 November 2021, with COVID-19 as the main cause of hospitalization. We ran Cox proportional hazards models adjusting for vaccination status, age, sex, county of residence, regional health authority, date of admission, country of birth, virus variant, and underlying risk factors. RESULTS We included 716 fully vaccinated patients (crude overall median LoS: 5.2 days; admitted to ICU: 103 (14%); in-hospital death: 86 (13%)) and 2487 unvaccinated patients (crude overall median LoS: 5.0 days; admitted to ICU: 480 (19%); in-hospital death: 102 (4%)). In adjusted models, fully vaccinated patients had a shorter overall LoS in hospital (adjusted log hazard ratios (aHR) for discharge: 1.61, 95% CI: 1.24-2.08), shorter LoS without ICU (aHR: 1.27, 95% CI: 1.07-1.52), and lower risk of ICU admission (aHR: 0.50, 95% CI: 0.37-0.69) compared to unvaccinated patients. We observed no difference in the LoS in ICU or in risk of in-hospital death between fully vaccinated and unvaccinated patients. DISCUSSION Fully vaccinated patients hospitalized with COVID-19 in Norway have a shorter LoS and lower risk of ICU admission than unvaccinated patients. These findings can support patient management and ongoing capacity planning in hospitals.
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Affiliation(s)
- Robert Whittaker
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway.
| | | | | | - Elina Seppälä
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Karan Golestani
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Reidar Kvåle
- Department of Anaesthesia and Intensive Care, Haukeland University Hospital, Bergen, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Sara Viksmoen Watle
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Eirik Alnes Buanes
- Department of Anaesthesia and Intensive Care, Haukeland University Hospital, Bergen, Norway; Norwegian Intensive Care and Pandemic Registry, Haukeland University Hospital, Bergen, Norway
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Brandal LT, MacDonald E, Veneti L, Ravlo T, Lange H, Naseer U, Feruglio S, Bragstad K, Hungnes O, Ødeskaug LE, Hagen F, Hanch-Hansen KE, Lind A, Watle SV, Taxt AM, Johansen M, Vold L, Aavitsland P, Nygård K, Madslien EH. Outbreak caused by the SARS-CoV-2 Omicron variant in Norway, November to December 2021. Euro Surveill 2021; 26:2101147. [PMID: 34915975 PMCID: PMC8728491 DOI: 10.2807/1560-7917.es.2021.26.50.2101147] [Citation(s) in RCA: 190] [Impact Index Per Article: 63.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 12/15/2021] [Indexed: 11/20/2022] Open
Abstract
In late November 2021, an outbreak of Omicron SARS-CoV-2 following a Christmas party with 117 attendees was detected in Oslo, Norway. We observed an attack rate of 74% and most cases developed symptoms. As at 13 December, none have been hospitalised. Most participants were 30-50 years old. Ninety-six percent of them were fully vaccinated. These findings corroborate reports that the Omicron variant may be more transmissible, and that vaccination may be less effective in preventing infection compared with Delta.
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Affiliation(s)
| | | | | | | | - Heidi Lange
- Norwegian Institute of Public Health, Oslo, Norway
| | - Umaer Naseer
- Norwegian Institute of Public Health, Oslo, Norway
| | | | | | - Olav Hungnes
- Norwegian Institute of Public Health, Oslo, Norway
| | | | | | | | - Andreas Lind
- Department of Microbiology, Oslo University Hospital, Oslo, Norway
| | | | - Arne M Taxt
- Norwegian Institute of Public Health, Oslo, Norway
| | - Mia Johansen
- Norwegian Institute of Public Health, Oslo, Norway
| | - Line Vold
- Norwegian Institute of Public Health, Oslo, Norway
| | | | - Karin Nygård
- Norwegian Institute of Public Health, Oslo, Norway
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10
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Seppälä E, Veneti L, Starrfelt J, Danielsen AS, Bragstad K, Hungnes O, Taxt AM, Watle SV, Meijerink H. Vaccine effectiveness against infection with the Delta (B.1.617.2) variant, Norway, April to August 2021. Euro Surveill 2021; 26:2100793. [PMID: 34477054 PMCID: PMC8414959 DOI: 10.2807/1560-7917.es.2021.26.35.2100793] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 09/02/2021] [Indexed: 11/20/2022] Open
Abstract
Some variants of SARS-CoV-2 are associated with increased transmissibility, increased disease severity or decreased vaccine effectiveness (VE). In this population-based cohort study (n = 4,204,859), the Delta variant was identified in 5,430 (0.13%) individuals, of whom 84 were admitted to hospital. VE against laboratory confirmed infection with the Delta variant was 22.4% among partly vaccinated (95% confidence interval (CI): 17.0-27.4) and 64.6% (95% CI: 60.6-68.2) among fully vaccinated individuals, compared with 54.5% (95% CI: 50.4-58.3) and 84.4% (95%CI: 81.8-86.5) against the Alpha variant.
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Affiliation(s)
- Elina Seppälä
- Department of infectious disease control and vaccines, Norwegian Institute of Public Health, Oslo, Norway
- ECDC Fellowship Programme, Field Epidemiology path (EPIET), European Centre for Disease Prevention and Control, (ECDC), Stockholm, Sweden
| | - Lamprini Veneti
- Department of infectious disease control and preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Jostein Starrfelt
- Department of infectious disease control and preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Anders Skyrud Danielsen
- Department of infectious disease control and preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Karoline Bragstad
- Department of virology, Norwegian Institute of Public Health, Oslo, Norway
| | - Olav Hungnes
- Department of virology, Norwegian Institute of Public Health, Oslo, Norway
| | - Arne Michael Taxt
- Department of infectious disease control and vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Sara Viksmoen Watle
- Department of infectious disease control and vaccines, Norwegian Institute of Public Health, Oslo, Norway
| | - Hinta Meijerink
- Department of infectious disease control and vaccines, Norwegian Institute of Public Health, Oslo, Norway
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11
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Watle SV, Næss LM, Tunheim G, Caugant DA, Wisløff T. Cost-effectiveness of meningococcal vaccination of Norwegian teenagers with a quadrivalent ACWY conjugate vaccine. Hum Vaccin Immunother 2021; 17:2777-2787. [PMID: 33631080 PMCID: PMC8475610 DOI: 10.1080/21645515.2021.1880209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
In Norway, the incidence of invasive meningococcal disease (IMD) is higher among 16–19-year-olds than in the general population. Most IMD cases among teenagers are caused by serogroup Y. Since 2011, one dose of meningococcal ACWY conjugate vaccine (MCV4) has been recommended for teenagers with out-of-pocket payment. The teenagers are usually vaccinated through the school health service at age 18. This study aimed to estimate costs and health gains of introducing MCV4 to Norwegian teenagers through the national immunization program (NIP). A Markov model was used to analyze the cost-effectiveness of universal MCV4 vaccination of either 15-year-olds or 18-years-olds. Occurrences of IMD were simulated from 15 until 23 years of age. Costs were estimated from a healthcare perspective. Sensitivity analyses evaluated the impact of vaccine price, vaccination uptake, IMD incidence and discount rate. Compared to today’s practice of vaccinating 18-year-olds with out-of-pocket payment, introducing MCV4 to 15-year-olds in a NIP-setting, with 90% vaccine uptake and 50% rebate on vaccine price, prevented 3.2 hospitalizations, 0.20 sequelae and 0.47 deaths among 15–23-year-olds, annually. Total costs were reduced by €30,000 and 9.7 quality-adjusted life-years (QALYs) were gained per birth cohort. The probability of cost-effectiveness was 99.0%, assuming a willingness-to-pay threshold of €86,000/QALY for severe diseases in Norway. Cost-effectiveness was highly dependent on vaccine price. Vaccination of 18-year-olds in a NIP-setting was also cost-effective, but less than NIP-vaccination of 15-year-olds. Introduction of MCV4 to the 15-year-olds in the Norwegian NIP is likely to be cost-effective given a rebate on the vaccine price.
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Affiliation(s)
- Sara Viksmoen Watle
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.,Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Lisbeth Meyer Næss
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Gro Tunheim
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Dominique A Caugant
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.,Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Torbjørn Wisløff
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.,Department of Community Medicine, Institute of Community Medicine, UiT the Arctic University of Norway, Tromsø, Norway
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12
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Pottegård A, Lund LC, Karlstad Ø, Dahl J, Andersen M, Hallas J, Lidegaard Ø, Tapia G, Gulseth HL, Ruiz PLD, Watle SV, Mikkelsen AP, Pedersen L, Sørensen HT, Thomsen RW, Hviid A. Arterial events, venous thromboembolism, thrombocytopenia, and bleeding after vaccination with Oxford-AstraZeneca ChAdOx1-S in Denmark and Norway: population based cohort study. BMJ 2021; 373:n1114. [PMID: 33952445 PMCID: PMC8097496 DOI: 10.1136/bmj.n1114] [Citation(s) in RCA: 241] [Impact Index Per Article: 80.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To assess rates of cardiovascular and haemostatic events in the first 28 days after vaccination with the Oxford-AstraZeneca vaccine ChAdOx1-S in Denmark and Norway and to compare them with rates observed in the general populations. DESIGN Population based cohort study. SETTING Nationwide healthcare registers in Denmark and Norway. PARTICIPANTS All people aged 18-65 years who received a first vaccination with ChAdOx1-S from 9 February 2021 to 11 March 2021. The general populations of Denmark (2016-18) and Norway (2018-19) served as comparator cohorts. MAIN OUTCOME MEASURES Observed 28 day rates of hospital contacts for incident arterial events, venous thromboembolism, thrombocytopenia/coagulation disorders, and bleeding among vaccinated people compared with expected rates, based on national age and sex specific background rates from the general populations of the two countries. RESULTS The vaccinated cohorts comprised 148 792 people in Denmark (median age 45 years, 80% women) and 132 472 in Norway (median age 44 years, 78% women), who received their first dose of ChAdOx1-S. Among 281 264 people who received ChAdOx1-S, the standardised morbidity ratio for arterial events was 0.97 (95% confidence interval 0.77 to 1.20). 59 venous thromboembolic events were observed in the vaccinated cohort compared with 30 expected based on the incidence rates in the general population, corresponding to a standardised morbidity ratio of 1.97 (1.50 to 2.54) and 11 (5.6 to 17.0) excess events per 100 000 vaccinations. A higher than expected rate of cerebral venous thrombosis was observed: standardised morbidity ratio 20.25 (8.14 to 41.73); an excess of 2.5 (0.9 to 5.2) events per 100 000 vaccinations. The standardised morbidity ratio for any thrombocytopenia/coagulation disorders was 1.52 (0.97 to 2.25) and for any bleeding was 1.23 (0.97 to 1.55). 15 deaths were observed in the vaccine cohort compared with 44 expected. CONCLUSIONS Among recipients of ChAdOx1-S, increased rates of venous thromboembolic events, including cerebral venous thrombosis, were observed. For the remaining safety outcomes, results were largely reassuring, with slightly higher rates of thrombocytopenia/coagulation disorders and bleeding, which could be influenced by increased surveillance of vaccine recipients. The absolute risks of venous thromboembolic events were, however, small, and the findings should be interpreted in the light of the proven beneficial effects of the vaccine, the context of the given country, and the limitations to the generalisability of the study findings.
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Affiliation(s)
- Anton Pottegård
- Clinical Pharmacology, Pharmacy, and Environmental Medicine, Department of Public Health, University of Southern Denmark, Odense, Denmark
| | - Lars Christian Lund
- Clinical Pharmacology, Pharmacy, and Environmental Medicine, Department of Public Health, University of Southern Denmark, Odense, Denmark
| | | | - Jesper Dahl
- Norwegian Institute of Public Health, Oslo, Norway
| | - Morten Andersen
- Pharmacovigilance Research Centre, Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Hallas
- Clinical Pharmacology, Pharmacy, and Environmental Medicine, Department of Public Health, University of Southern Denmark, Odense, Denmark
| | - Øjvind Lidegaard
- Department of Gynaecology, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - German Tapia
- Norwegian Institute of Public Health, Oslo, Norway
| | | | | | | | - Anders Pretzmann Mikkelsen
- Department of Gynaecology, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Lars Pedersen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Henrik Toft Sørensen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Reimar Wernich Thomsen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Anders Hviid
- Pharmacovigilance Research Centre, Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
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13
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Henao-Restrepo AM, Camacho A, Longini IM, Watson CH, Edmunds WJ, Egger M, Carroll MW, Dean NE, Diatta I, Doumbia M, Draguez B, Duraffour S, Enwere G, Grais R, Gunther S, Gsell PS, Hossmann S, Watle SV, Kondé MK, Kéïta S, Kone S, Kuisma E, Levine MM, Mandal S, Mauget T, Norheim G, Riveros X, Soumah A, Trelle S, Vicari AS, Røttingen JA, Kieny MP. Efficacy and effectiveness of an rVSV-vectored vaccine in preventing Ebola virus disease: final results from the Guinea ring vaccination, open-label, cluster-randomised trial (Ebola Ça Suffit!). Lancet 2017; 389:505-518. [PMID: 28017403 PMCID: PMC5364328 DOI: 10.1016/s0140-6736(16)32621-6] [Citation(s) in RCA: 675] [Impact Index Per Article: 96.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 11/25/2016] [Accepted: 12/06/2016] [Indexed: 12/16/2022]
Abstract
BACKGROUND rVSV-ZEBOV is a recombinant, replication competent vesicular stomatitis virus-based candidate vaccine expressing a surface glycoprotein of Zaire Ebolavirus. We tested the effect of rVSV-ZEBOV in preventing Ebola virus disease in contacts and contacts of contacts of recently confirmed cases in Guinea, west Africa. METHODS We did an open-label, cluster-randomised ring vaccination trial (Ebola ça Suffit!) in the communities of Conakry and eight surrounding prefectures in the Basse-Guinée region of Guinea, and in Tomkolili and Bombali in Sierra Leone. We assessed the efficacy of a single intramuscular dose of rVSV-ZEBOV (2×107 plaque-forming units administered in the deltoid muscle) in the prevention of laboratory confirmed Ebola virus disease. After confirmation of a case of Ebola virus disease, we definitively enumerated on a list a ring (cluster) of all their contacts and contacts of contacts including named contacts and contacts of contacts who were absent at the time of the trial team visit. The list was archived, then we randomly assigned clusters (1:1) to either immediate vaccination or delayed vaccination (21 days later) of all eligible individuals (eg, those aged ≥18 years and not pregnant, breastfeeding, or severely ill). An independent statistician generated the assignment sequence using block randomisation with randomly varying blocks, stratified by location (urban vs rural) and size of rings (≤20 individuals vs >20 individuals). Ebola response teams and laboratory workers were unaware of assignments. After a recommendation by an independent data and safety monitoring board, randomisation was stopped and immediate vaccination was also offered to children aged 6-17 years and all identified rings. The prespecified primary outcome was a laboratory confirmed case of Ebola virus disease with onset 10 days or more from randomisation. The primary analysis compared the incidence of Ebola virus disease in eligible and vaccinated individuals assigned to immediate vaccination versus eligible contacts and contacts of contacts assigned to delayed vaccination. This trial is registered with the Pan African Clinical Trials Registry, number PACTR201503001057193. FINDINGS In the randomised part of the trial we identified 4539 contacts and contacts of contacts in 51 clusters randomly assigned to immediate vaccination (of whom 3232 were eligible, 2151 consented, and 2119 were immediately vaccinated) and 4557 contacts and contacts of contacts in 47 clusters randomly assigned to delayed vaccination (of whom 3096 were eligible, 2539 consented, and 2041 were vaccinated 21 days after randomisation). No cases of Ebola virus disease occurred 10 days or more after randomisation among randomly assigned contacts and contacts of contacts vaccinated in immediate clusters versus 16 cases (7 clusters affected) among all eligible individuals in delayed clusters. Vaccine efficacy was 100% (95% CI 68·9-100·0, p=0·0045), and the calculated intraclass correlation coefficient was 0·035. Additionally, we defined 19 non-randomised clusters in which we enumerated 2745 contacts and contacts of contacts, 2006 of whom were eligible and 1677 were immediately vaccinated, including 194 children. The evidence from all 117 clusters showed that no cases of Ebola virus disease occurred 10 days or more after randomisation among all immediately vaccinated contacts and contacts of contacts versus 23 cases (11 clusters affected) among all eligible contacts and contacts of contacts in delayed plus all eligible contacts and contacts of contacts never vaccinated in immediate clusters. The estimated vaccine efficacy here was 100% (95% CI 79·3-100·0, p=0·0033). 52% of contacts and contacts of contacts assigned to immediate vaccination and in non-randomised clusters received the vaccine immediately; vaccination protected both vaccinated and unvaccinated people in those clusters. 5837 individuals in total received the vaccine (5643 adults and 194 children), and all vaccinees were followed up for 84 days. 3149 (53·9%) of 5837 individuals reported at least one adverse event in the 14 days after vaccination; these were typically mild (87·5% of all 7211 adverse events). Headache (1832 [25·4%]), fatigue (1361 [18·9%]), and muscle pain (942 [13·1%]) were the most commonly reported adverse events in this period across all age groups. 80 serious adverse events were identified, of which two were judged to be related to vaccination (one febrile reaction and one anaphylaxis) and one possibly related (influenza-like illness); all three recovered without sequelae. INTERPRETATION The results add weight to the interim assessment that rVSV-ZEBOV offers substantial protection against Ebola virus disease, with no cases among vaccinated individuals from day 10 after vaccination in both randomised and non-randomised clusters. FUNDING WHO, UK Wellcome Trust, the UK Government through the Department of International Development, Médecins Sans Frontières, Norwegian Ministry of Foreign Affairs (through the Research Council of Norway's GLOBVAC programme), and the Canadian Government (through the Public Health Agency of Canada, Canadian Institutes of Health Research, International Development Research Centre and Department of Foreign Affairs, Trade and Development).
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Affiliation(s)
| | - Anton Camacho
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Ira M Longini
- Department of Biostatistics, University of Florida, Gainesville, FL, USA
| | - Conall H Watson
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - W John Edmunds
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Matthias Egger
- Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland; Centre for Infectious Disease Epidemiology and Research, University of Cape Town, Cape Town, South Africa
| | | | - Natalie E Dean
- Department of Biostatistics, University of Florida, Gainesville, FL, USA
| | - Ibrahima Diatta
- Clinical Trials Unit Bern, University of Bern, Bern, Switzerland
| | - Moussa Doumbia
- WHO, Geneva, Switzerland; Centre National d'Appui à la Lutte contre la Maladie, Bamako, Mali
| | | | - Sophie Duraffour
- Bernard Nocht Institute for Tropical Medicine, University of Hamburg, Hamburg, Germany
| | | | | | - Stephan Gunther
- Bernard Nocht Institute for Tropical Medicine, University of Hamburg, Hamburg, Germany
| | | | | | - Sara Viksmoen Watle
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway
| | - Mandy Kader Kondé
- Center Of Excellence For Training, Research On Malaria & Priority Diseases In Guinea, Conakry, Guinea
| | - Sakoba Kéïta
- Ebola Response, Ministry of Health, Conakry, Guinea
| | | | - Eewa Kuisma
- Bernard Nocht Institute for Tropical Medicine, University of Hamburg, Hamburg, Germany
| | - Myron M Levine
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | | | - Gunnstein Norheim
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway
| | | | | | - Sven Trelle
- Clinical Trials Unit Bern, University of Bern, Bern, Switzerland
| | | | - John-Arne Røttingen
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway; Department of Health and Society, University of Oslo, Norway; Department of Global Health and Population, Harvard TH Chan School of Public Health, Boston, MA, USA; Coalition for Epidemic Preparedness Innovations, care of Norwegian Institute of Public Health, Oslo, Norway
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14
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Abstract
The 2014-16 Ebola outbreak in West Africa has by far been the largest and most devastating Ebola outbreak so far. At the start of the epidemic only 2 Ebola DNA vaccine candidates had been tested in clinical trials and the correlate of protection in humans was unknown. International stakeholders coordinated by the World Health Organization agreed to fast-track the development of 2 Ebola vaccine candidates, based on adenovirus and vesicular stomatitis virus (VSV) vectors. Phase I and II clinical trials were initiated in the autumn of 2014 and found both vaccines to be acceptable for proceeding to phase III trials. Despite the epidemic waning in the spring of 2015, by July 2015 preliminary results from a phase III trial in Guinea proved the Ebola VSV vaccine to be effective.
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Affiliation(s)
- Sara Viksmoen Watle
- Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Gunnstein Norheim
- Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - John-Arne Røttingen
- Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
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