L’article publié dans le Vif le 31/12/2021 est basé sur les références ci-dessous. L’article du Vif est une version raccourcie. L’article original incluant toutes les citations bibliographiques dans le texte est disponible ici
Les auteurs remercient V. Tilman, J-M Longneaux et L. Weynants pour les relectures.
Références:
Les Masques :
[m2] https://www.change.org/p/caroline-d%C3%A9sir-ministre-de-l-education-non-%C3%A0-l-obligation-du-port-du-masque-d%C3%A8s-6-ans
[m3] World Health Organization. Advice on the use of masks in the community, during home care and in health care settings in the context of the novel coronavirus (2019-nCoV) outbreak. Geneva, Switzerland; 2020. https://apps.who.int/iris/handle/10665/330987
[m4] World Health Organization. Advice on the use of masks in the context of COVID-19. Interim guidance 5 June 2020. https://apps.who.int/iris/handle/10665/332293 : Many countries have recommended the use of fabric masks/face coverings for the general public. At the present time, the widespread use of masks by healthy people in the community setting is not yet supported by high quality or direct scientific evidence and there are potential benefits and harms to consider (see below).
[m5] European Centre for Disease Prevention and Control, Questions and answers on COVID-19: Children aged 1 – 18 years and the role of school settings accessed on 16/12/2021, https://www.ecdc.europa.eu/en/covid-19/ questions-answers/questions-answers-school-transmission : While the Delta variant and other identified SARS-CoV-2 variants of concern appear to be more transmissible in both children and adults than previous variants, children do not appear to be more likely to be infected with or transmit the Delta variant. In primary schools, the use of face masks is recommended for teachers and other adults when physical distancing cannot be guaranteed, but it is not recommended for students.
[m6] Sciensano, SARS-COV-2 TRANSMISSION IN PRIMARY SCHOOL CHILDREN, 12 novembre 2020 https://covid-19.sciensano.be/sites/default/files/Covid19/20201112_Advice_RAG_transmission%20primary%20school_final_ENG.pdf
[m7] Sciensano, MASK-WEARING IN SCHOOL-AGED CHILDREN, Rapid evidence overview 29/10/2021, https://covid-19.sciensano.be/sites/default/files/Covid19/20212910_Advice_Sciensano_Mask-wearing%20in%20school-aged%20children.pdf
Efficacité des Masques:
[em1] Face masks to prevent transmission of influenza virus: a systematic review, Epidemiology & Infection, Volume 138 , Issue 4 , April 2010 , pp. 449 – 456.
[em2] https://www.cidrap.umn.edu/news-perspective/2020/04/commentary-masks-all-covid-19-not-based-sound-data. : Pas vraiment d’évidence pour le masque pour tous, surtout que risque de transmission par aérosol.
[em3] Respiratory virus shedding in exhaled breath and efficacy of face masks https://www.nature.com/articles/s41591-020-0843-2: Intérêt du masque pour gouttelette chez symptomatiques, chez asymptomatiques faibles différences surtout pour transmission aérosol qui est observée pour les coronavirus.
[em4] MacIntyre C.R., Seale H., Dung T.C., Hien N.T., Nga P.T., Chughtai A.A. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ open. 2015;5. This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. This is an important finding to inform occupational health and safety. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection.
[em5] Universal Masking in Hospitals in the Covid-19 Era, N Engl J Med 2020; 382:e63 DOI: 10.1056/NEJMp2006372. Article sur l’usage généralisés du masque en milieux hospitalier. We know that wearing a mask outside health care facilities offers little, if any, protection from infection. Public health authorities define a significant exposure to Covid-19 as face-to-face contact within 6 feet with a patient with symptomatic Covid-19 that is sustained for at least a few minutes (and some say more than 10 minutes or even 30 minutes). The chance of catching Covid-19 from a passing interaction in a public space is therefore minimal. In many cases, the desire for widespread masking is a reflexive reaction to anxiety over the pandemic. There may be additional benefits to broad masking policies that extend beyond their technical contribution to reducing pathogen transmission. Masks are visible reminders of an otherwise invisible yet widely prevalent pathogen and may remind people of the importance of social distancing and other infection-control measures.
[em6] Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks. https://pubs.acs.org/doi/10.1021/acsnano.0c03252.
[em7] Experimental investigation of indoor aerosol dispersion and accumulation in the context of COVID-19: Effects of masks and ventilation, Physics of Fluids 33, 073315 (2021); https://doi.org/10.1063/5.0057100.
[em8] A guideline to limit indoor airborne transmission of COVID-19M. Z. Bazant and J. W. M. Bush: PNAS April 27, 2021 118 (17) e2018995118; https://doi.org/10.1073/pnas.2018995118 MIT study on airborne transmission.
Masque et effets secondaires:
[me1] Covid-19: Important potential side effects of wearing face masks that we should bear in mind BMJ 2020;369:m2003 doi: 10.1136/bmj.m2003 (Published 21 May 2020).
[me2] Kao T.W., Huang K.C., Huang Y.L., Tsai T.J., Hsieh B.S., Wu M.S. The physiological impact of wearing an N95 mask during hemodialysis as a precaution against SARS in patients with end-stage renal disease. J Formos Med Assoc. 2004;103:624–628. https://pubmed.ncbi.nlm.nih.gov/15340662/ : Thirty nine patients (23 men; mean age, 57.2 years) were recruited for participation in the study. Seventy percent of the patients showed a reduction in partial pressure of oxygen (PaO2), and 19% developed various degrees of hypoxemia. Wearing an N95 mask significantly reduced the PaO2 level (101.7 +/- 12.6 to 92.7 +/- 15.8 mm Hg, p = 0.006), increased the respiratory rate (16.8 +/- 2.8 to 18.8 +/- 2.7/min, p < 0.001), and increased the occurrence of chest discomfort (3 to 11 patients, p = 0.014) and respiratory distress (1 to 17 patients, p < 0.001). Baseline PaO2 level was the only significant predictor of the magnitude of PaO2 reduction (p < 0.001). Conclusion: Wearing an N95 mask for 4 hours during HD significantly reduced PaO2 and increased respiratory adverse effects in ESRD patients.
[me3] Beder A., Buyukkocak U., Sabuncuoglu H., Keskil Z.A., Keskil S. Preliminary report on surgical mask induced deoxygenation during major surgery. Neurocirugia (Astur) 2008;19:121–126. https://pubmed.ncbi.nlm.nih.gov/18500410/ : This study was undertaken to evaluate whether the surgeons’ oxygen saturation of hemoglobin was affected by the surgical mask or not during major operations. Repeated measures, longitudinal and prospective observational study was performed on 53 surgeons using a pulse oximeter pre and postoperatively. Our study revealed a decrease in the oxygen saturation of arterial pulsations (SpO2) and a slight increase in pulse rates compared to preoperative values in all surgeon groups. The decrease was more prominent in the surgeons aged over 35.
[me4] Ong J.J.Y., Bharatendu C., Goh Y., Tang J.Z.Y., Sooi K.W.X., Tan Y.L. Headaches Associated With Personal Protective Equipment – A Cross-Sectional Study Among Frontline Healthcare Workers During COVID-19. Headache. 2020;60:864–877. [PubMed] [Google Scholar] : Coronavirus disease 2019 (COVID-19) is an emerging infectious disease of pandemic proportions. Healthcare workers in Singapore working in high-risk areas were mandated to wear personal protective equipment (PPE) such as N95 face mask and protective eyewear while attending to patients. Most healthcare workers develop de novo PPE-associated headaches or exacerbation of their pre-existing headache disorders.
[me6] Kisielinski K, Giboni P, Prescher A, Klosterhalfen B, Graessel D, Funken S, Kempski O, Hirsch O. Is a Mask That Covers the Mouth and Nose Free from Undesirable Side Effects in Everyday Use and Free of Potential Hazards? International Journal of Environmental Research and Public Health. 2021; 18(8):4344. https://doi.org/10.3390/ijerph18084344
Aération et ventilation:
[a1] Conseil Supérieur de la Santé, SARS-COV-2 ET L’UTILISATION DES SYSTÈMES D’AÉRATION PASSIVE, VENTILATION MÉCANIQUE, AIR-CONDITIONNÉ ET FILTRES HORS HÔPITAL ET INSTITUTIONS DE SOINS, MAI 2020. https://www.health.belgium.be/sites/default/files/uploads/fields/fpshealth_theme_file/200604_css-9599_covid-19_ventilation_vweb.pdf
[a2] A propos de l’efficacité des aérations et ventilations pour juguler les risques épidémiologiques en lieux clos – Le blog du #covidrationnel
[a3] Du CR, Wang SC, Yu MC, Chiu TF, Wang JY, Chuang PC, Jou R, Chan PC, Fang CT. Effect of ventilation improvement during a tuberculosis outbreak in underventilated university buildings. Indoor Air. 2020 May;30(3):422-432. doi: 10.1111/ina.12639. Epub 2020 Jan 16. PMID: 31883403; PMCID: PMC7217216.
Transmission virale:
[t1] A study on infectivity of asymptomatic SARS-CoV-2 carriers, Respir Med. 2020 Aug; 169: 106026. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7219423/: 455 contacts who were exposed to the asymptomatic COVID-19 virus carrier became the subjects of our research. The median contact time for patients was four days and that for family members was five days. All CT images showed no sign of COVID-19 infection. No severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections was detected in 455 contacts by nucleic acid test. In summary, all the 455 contacts were excluded from SARS-CoV-2 infection and we conclude that the infectivity of some asymptomatic SARS-CoV-2 carriers might be weak.
[t2] Contact Settings and Risk for Transmission in 3410 Close Contacts of Patients With COVID-19 in Guangzhou, China. https://www.acpjournals.org/doi/10.7326/M20-2671: Infection max dans foyer (10x plus que à l’hôpital et 100x plus que dans transport en commun) et augmente fortement avec la force des symptomes (asymptomatiques 10 à 20 fois moins contagieux) et la toux.: Among 3410 close contacts, 127 (3.7% [95% CI, 3.1% to 4.4%]) were secondarily infected. Of these 127 persons, 8 (6.3% [CI, 2.1% to 10.5%]) were asymptomatic. Of the 119 symptomatic cases, 20 (16.8%) were defined as mild, 87 (73.1%) as moderate, and 12 (10.1%) as severe or critical. Compared with the household setting (10.3%), the secondary attack rate was lower for exposures in health care settings (1.0%; odds ratio [OR], 0.09 [CI, 0.04 to 0.20]) and on public transportation (0.1%; OR, 0.01 [CI, 0.00 to 0.08]). The secondary attack rate increased with the severity of index cases, from 0.3% (CI, 0.0% to 1.0%) for asymptomatic to 3.3% (CI, 1.8% to 4.8%) for mild, 5.6% (CI, 4.4% to 6.8%) for moderate, and 6.2% (CI, 3.2% to 9.1%) for severe or critical cases. Index cases with expectoration were associated with higher risk for secondary infection (13.6% vs. 3.0% for index cases without expectoration; OR, 4.81 [CI, 3.35 to 6.93]).
[t3] Analysis of Asymptomatic and Presymptomatic Transmission in SARS-CoV-2 Outbreak, Germany, 2020, EID Journal, 27 (4), April 2021, https://wwwnc.cdc.gov/eid/article/27/4/20-4576_article: We determined secondary attack rates (SAR) among close contacts of 59 asymptomatic and symptomatic coronavirus disease case-patients by presymptomatic and symptomatic exposure. We observed no transmission from asymptomatic case-patients and highest SAR through presymptomatic exposure. Rapid quarantine of close contacts with or without symptoms is needed to prevent presymptomatic transmission.
[t4] Coronavirus Disease Outbreak in Call Center, South Korea, EID Journal,Volume 26, Number 8—August 2020: https://wwwnc.cdc.gov/eid/article/26/8/20-1274_article#r6: We describe the epidemiology of a coronavirus disease (COVID-19) outbreak in a call center in South Korea. We obtained information on demographic characteristics by using standardized epidemiologic investigation forms. We performed descriptive analyses and reported the results as frequencies and proportions for categoric variables. Of 1,143 persons who were tested for COVID-19, a total of 97 (8.5%, 95% CI 7.0%–10.3%) had confirmed cases. Of these, 94 were working in an 11th-floor call center with 216 employees, translating to an attack rate of 43.5% (95% CI 36.9%–50.4%). The household secondary attack rate among symptomatic case-patients was 16.2% (95% CI 11.6%– 22.0%). Of the 97 persons with confirmed COVID-19, only 4 (1.9%) remained asymptomatic within 14 days of quarantine, and none of their household contacts acquired secondary infections. Extensive contact tracing, testing all contacts, and early quarantine blocked further transmission and might be effective for containing rapid outbreaks in crowded work settings.
[t5] Cheng H, Jian S, Liu D, et al. Contact Tracing Assessment of COVID-19 Transmission Dynamics in Taiwan and Risk at Different Exposure Periods Before and After Symptom Onset. JAMA Intern Med. 2020;180(9):1156–1163. doi:10.1001/jamainternmed.2020.2020: https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2765641 : In this case-ascertained study of 100 cases of confirmed COVID-19 and 2761 close contacts, the overall secondary clinical attack rate was 0.7%. The attack rate was higher among contacts whose exposure to the index case started within 5 days of symptom onset than those who were exposed later. Among the 91 close contacts of the 9 asymptomatic cases, no secondary transmission was observed.
[t6] Post-lockdown SARS-CoV-2 nucleic acid screening in nearly ten million residents of Wuhan, China Étude sur les asymptomatiques PCR-positifs à Wuhan. Cao et al, dans la revue Nature https://www.nature.com/articles/s41467-020-19802-w
[t7] Qiu X, et al. Defining the role of asymptomatic and pre-symptomatic SARS-CoV-2 transmission, a living systematic review. 2021 Jan 20. Clin Microbiol Infect. 2021; S1198-743X(21)00038-0. doi:10.1016/j.cmi.2021.01.011
[t8] COVID-19 transmission—up in the air The Lancet Respiratory Medicine Crossref DOI link: https://doi.org/10.1016/S2213-2600(20)30514-2 Published: 2020-12 : Respiratory viruses are transmitted in three main ways. First, contact transmission, where someone comes into direct contact with an infected person or touches a surface that has been contaminated. Second, through droplet transmission of both large and small respiratory droplets that contain the virus, which would occur when near an infected person. Third, through airborne transmission of smaller droplets and particles that are suspended in the air over longer distances and time than droplet transmission. Initially it was thought that airborne transmission of SARS-CoV-2 was unlikely, but growing evidence has highlighted that infective microdroplets are small enough to remain suspended in the air and expose individuals at distances beyond 2 m from an infected person. This knowledge is also corroborated by investigation of spread of cases between people who were not in direct or indirect contact, suggesting that airborne transmission was the most likely route. In July, over 200 scientists published a statement calling for international bodies to recognise the potential for airborne spread of COVID-19 as they were concerned that people would not be fully protected by adhering to the current recommendations.
[t9] Outdoor Transmission of SARS-CoV-2 and Other Respiratory Viruses: A Systematic Review J Infect Dis. 2021 Feb 24;223(4):550-561. doi: 10.1093/infdis/jiaa742:Five identified studies found a low proportion of reported global SARS-CoV-2 infections occurred outdoors (<10%) and the odds of indoor transmission was very high compared to outdoors (18.7 times; 95% confidence interval, 6.0-57.9). Existing evidence supports the wide-held belief that risk of SARS-CoV-2 transmission is lower outdoors but there are significant gaps in our understanding of specific pathways.
[t10] https://www.lci.fr/sante/video-covid-19-le-port-du-masque-a-l-exterieur-est-il-utile-2162627.html: Risque de contagion très faible en extérieurs.
[t11] https://www.youtube.com/watch?v=mrXBinu3Swo : Le port du masque en extérieur ne sert à rien! » Dr Blachier, études à l’appui! 26 Avril 2021. Il dit encore: Très peu de contaminations se font en extérieur, d’après plusieurs études.On devrait dire aux gens de se retrouver dehors plutôt qu’à l’intérieur. Le port du masque en extérieur ne sert à rien! Dr Blachier – Épidémiologiste. Émission : Les Grandes Gueules Chaîne : RMC STORY / RMC (Radio).
[t12] https://www.tdg.ch/les-effusions-de-joie-a-moutier-ne-font-pas-exploser-les-cas-830669237575?fbclid=IwAR11X7WwnJB7b2jF1aMOS vzbt2NkccPd9livLPi5RJDVH4BnHjjx7BzzRFM « Jacques Gerber, ministre jurassien de la Santé, le confirme: «Ce dimanche, nous avons enregistré six cas, contre une vingtaine en fin de semaine. Nous sommes clairement en descente. Il n’y a donc pas d’explosion. C’est un cas d’école.» Aucune flambée non plus à Moutier et dans le Jura bernois, avec même une
[t13] Wölfel R. et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020 May;581(7809):465-469. doi : 10.1038/s41586-020-2196-x. Epub 2020 Apr 1. Erratum in : Nature. 2020 Dec;588(7839):E35. PMID : 32235945
[t14] La Scola B et al. Viral RNA load as determined by cell culture as a management tool for discharge of SARS-CoV-2 patients from infectious disease wards. Eur J Clin Microbiol Infect Dis. 2020 Jun;39(6):1059-1061. doi : 10.1007/s10096-020- 03913-9.
[t15] RAG interpretation and reporting of SARS COV-2 PCR results (Sciensano) 20201208_Advice RAG Interpretation and reporting of COVID PCR results.pdf (sciensano.be)
Transmission et masque chez l’enfant :
[te1] Association between living with children and outcomes from covid-19: OpenSAFELY cohort study of 12 million adults in England, BMJ 2021; 372. (Published 18 March 2021), https://doi.org/10.1136/bmj.n628 : Among 9 334 392adults aged 65 years and under, during wave 1, living with children was not associated with materially increased risks of recorded SARS-CoV-2 infection, covid-19 related hospital or intensive care admission, or death from covid-19. In wave 2, among adults aged 65 years and under living with children was associated with a very small increased risk, e.g., in the number of hospital admissions of 1-5 per 10 000 people from 160 to between 161 and 165 (children aged 0-11) and with an increase of an increase of 2-6 per 10 000 (children aged 12-18 years).
[te2]https://www.lefigaro.fr/vox/societe/il-faut-urgemment-mettre-fin-au-port-du-masque-pour-les-enfants-20210525?fbclid=IwAR2x3N2f4kZHTRiOV97HosF1AGb2WlJcdZQeQmsFR3aA9F5VZN4cTkAZjDk : Masquer les enfants pour une maladie qui ne les concerne pas signifie notre défaite de la pensée et notre perte de dignité. Psychologues, pédiatres et pédopsychiatres, nous sommes nombreux à être très inquiets de la hausse des hospitalisations et des troubles que développent les jeunes enfants depuis le premier confinement. Jusqu'à six fois plus d'admissions en pédopsychiatrie.
[te3] Covid-19 dans les écoles primaires : pas de transmission importante du virus entre enfants ou vers les enseignants | Institut Pasteur
[te4] https://www.theguardian.com/australia-news/2021/sep/08/the-delta-covid-variant-and-children-transmission-in-kids-is-low-and-only -2-hospitalised-report-finds
[te5] Open Schools, Covid-19, and Child and Teacher Morbidity in Sweden, N Engl J Med 2021; 384:669-671, DOI: 10.1056/NEJMc2026670
[te6] COVID-19 in schools and early childhood education and care services – the experience in NSW: 16 June to 31 July 2021 - National Centre for Immunisation Research and Surveillance (NCIRS), 8 septembre 2021: https://www.ncirs.org.au/sites/default/files/2021-09/NCIRS%20NSW%20Schools%20COVID_Summary_8%20September%2021_Final.pdf
[te7] Loske, J., Röhmel, J., Lukassen, S. et al. Pre-activated antiviral innate immunity in the upper airways controls early SARS-CoV-2 infection in children. Nat Biotechnol (2021). https://doi.org/10.1038/s41587-021-01037-9
[te8] Note de l’INSERM : Voici pourquoi les enfants font moins de formes grave de la Covid-19, https://www-futura--sciences-com.cdn.ampproject.org/c/s/www.futura-sciences.com/alternative/amp/actualite/83130/
[te9] Exhaled aerosol increases with COVID-19 infection, age, and obesity, David A. Edwards, et al., Proceedings of the National Academy of Sciences Feb 2021, 118 (8) e2021830118; DOI: 10.1073/pnas.2021830118
[te11] https://www.lefigaro.fr/vox/societe/l-appel-des-orthophonistes-contre-le-retour-du-masque-a-l-ecole-de-primaire-20211115
Immunité:
[i1] Heffron AS, McIlwain SJ, Amjadi MF, Baker DA, Khullar S, Armbrust T, et al. (2021) The landscape of antibody binding in SARS-CoV-2 infection. PLoS Biol 19(6): e3001265. https://doi.org/10.1371/journal.pbio.3001265 : SARS-CoV-2 infections may trigger antibody responses against multiple virus proteins, not only the spike protein, which is an advantage to protect about new variant and immunity escape.
[i2] Antibody Evolution after SARS-CoV-2 mRNA Vaccination, https://www.biorxiv.org/content/10.1101/2021.07.29.454333v2 : L’infection par le SRAS-CoV-2 produit des réponses des cellules B qui continuent d’évoluer pendant au moins un an. Au cours de cette période, les cellules B mémoires expriment des anticorps de plus en plus larges et puissants qui sont résistants aux mutations trouvées dans les variants préoccupants.
[i3] Turner, J.S., Kim, W., Kalaidina, E. et al. SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans. Nature 595, 421–425 (2021). https://doi.org/10.1038/s41586-021-03647-4.
[i4] Had COVID? You’ll probably make antibodies for a lifetime https://www.nature.com/articles/d41586-021-01442-9, doi: https://doi.org/10.1038/d41586-021-01442-9,
[i5] SARS-CoV-2 elicits robust adaptive immune responses regardless of disease severity, https://www.thelancet.com/journals/ebiom/article/PIIS2352-3964(21)00203-6/fulltext
[i6] https://www.nytimes.com/2021/05/26/health/coronavirus-immunity-vaccines.html
[i7] https://www.washingtonpost.com/outlook/2021/09/15/natural-immunity-vaccine-mandate/
[i8] Comparing SARS-CoV-2 natural immunity to vaccine-induced immunity: reinfections versus breakthrough infections https://www.medrxiv.org/content/10.1101/2021.08.24.21262415v1
[i9] 14.4% en Novembre 2021 en BE, 33% en Juin 2021 en Suisse, et entre 7 et 10% d’augmentation par vague épidémique, le professeur Finn, de l'université de Bristol et conseiller du gouvernement britannique en matière de vaccins estimait en Aout 2021 que 40 à 50% des enfants ont déjà été infectés https://www.bbc.com/afrique/monde-55400773.
[i10] Vaccinating people who have had covid-19: why doesn’t natural immunity count in the US? BMJ 2021;374:n2101 doi: https://doi.org/10.1136/bmj.n2101 : The US CDC estimates that SARS-CoV-2 has infected more than 100 million Americans, and evidence is mounting that natural immunity is at least as protective as vaccination.
Aspects Juridiques :
[j1] aff. Elsholz C. Allemagne,Sommerfeld C. Allemagne; Bronda c. Italie; Van Bueren, G., Les droits des enfants en Europe, Strasbourg, Ed. du Conseil de l’Europe, 2008, p.39.