Références notables de bibliographie sur la Covid-19

Publié par Bernard Pradines

Références notables de bibliographie sur la Covid-19

Sans me livrer à une vraie revue de la littérature scientifique, je repère les publications qui me semblent dignes d’intérêt depuis le 18 mars 2021 dans le listing quotidien de Kamps et Hoffmann : https://covidreference.com/top10

A noter que les mises à jour de cette page ne feront pas systématiquement l'objet d'un avis de publication par courriel comme les autres articles.

Remarques en français en caractères bleus.

12 avril 2021

Sunday evening: Cold, heavy rain. Curfew. Exponential growth of infections. ICUs on the limit, vaccines are still in shortage. Politicians quarrel over lockdown rules. Everyone tired. Johnson & Johnson’s vaccine may bear the same clotting risk as Astra Zeneca’s Vaxzevria®: https://www.ema.europa.eu/en/news/meeting-highlights-pharmacovigilance-risk-assessment-committee-prac-6-9-april-2021

Johnson & Johnson : anaphlaxie et thromboembolie observées de prés dans les essais cliniques avant la phase IV et à son décours.

Depressed? Well, here are some good news.

Shen X, Tang H, Pajon R, et al. Neutralization of SARS-CoV-2 Variants B.1.429 and B.1.351. NEJM April 7, 2021. https://www.nejm.org/doi/full/10.1056/NEJMc2103740?query=featured_home

Sacré africain du sud : même pas peur.

Vaccine-elicited neutralizing antibodies are likely to remain effective against the B.1.429 variant (“California”). The modestly lower value in neutralization titers was similar to B.1.1.7, using serum from recipients of the mRNA-1273 (Moderna) and NVX-CoV2373 (Novavax). The magnitude of resistance seen with the B.1.351 variant is of greater concern. However, this is good news, because immune escape seems to be limited in most variants.

Ramakrishnan S, Nicolau Jr DV, Langford B, et al. Inhaled budesonide in the treatment of early COVID-19 (STOIC): a phase 2, open-label, randomised controlled trial. Lancet Resp Med April 09, 2021. https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(21)00160-0/fulltext

Un corticoïde inhalé efficace ?

In this open-label, phase 2 RCT in 146 adults with mild COVID-19 symptoms, early administration of inhaled budesonide within 7 days reduced the likelihood of needing urgent medical care (1% vs 14%) and reduced time to recovery after early COVID-19. The number needed to treat with inhaled budesonide to reduce COVID-19 deterioration was eight. According to the authors, their findings “require urgent validation and dissemination”. However, this encouraging early data is good news and the differences in the endpoints are impressive. Inhaled budesonide is a simple, safe, well studied, inexpensive, and widely available treatment. A game changer – if confirmed by a phase 3 RCT.

Références notables de bibliographie sur la Covid-19

11 avril 2021

Greinacher A, Thiele T, Warkentin TE, et al. Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination. NEJM April 9, 2021. https://www.nejm.org/doi/full/10.1056/NEJMoa2104840?query=featured_home

Vers une confirmation du mécanisme TIH-like

A case series of 11 patients (9 women) from Germany and Austria in whom thrombosis or thrombocytopenia developed after vaccination with ChAdOx1 nCov-19. All had moderate-to-severe thrombocytopenia and thrombotic complications at unusual sites beginning 5-16 days after first vaccination. All had platelet-activating antibodies directed against platelet factor 4 (PF4)–heparin.

Schultz NH, Sørvoll ICH, Michelsen AE, et al. Thrombosis and Thrombocytopenia after ChAdOx1 nCoV-19 Vaccination. NEJM April 9, 2021. https://www.nejm.org/doi/full/10.1056/NEJMoa2104882?query=featured_home

Idem publication ci-dessus de Greinacher et al.

Another five patients (four women) from Norway. Same findings.

10 avril 2021

Havervall S, Rosell A, Phillipson M, et al. Symptoms and Functional Impairment Assessed 8 Months After Mild COVID-19 Among Health Care Workers. JAMA April 7, 2021, https://jamanetwork.com/journals/jama/fullarticle/2778528?resultClick=1

Covid long chez des travailleurs de la santé séropositifs ou non au SARS-CoV-2 (voir image ci-dessous)

Probably one of the best longitudinal studies on long COVID-19 to date, comparing 323 seropositive (with mild disease) vs 1072 seronegative HCW. At 8 months, 15% vs 3% (at 2 months: 26% vs 9%) reported at least one moderate to severe symptom. Symptoms disrupted work, social, and home life.

Références notables de bibliographie sur la Covid-19

Van Praet JT, Vandecasteele S, de Roo A, et al. Humoral and cellular immunogenicity of the BNT162b2 mRNA Covid-19 Vaccine in nursing home residents. Clin Inf Dis, ciab300, April 7, 2021. https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciab300/6213866?searchresult=1

Des résultats peu surprenants si l'on en juge par la seule immunosénescence. Toutefois à confirmer. 

Four weeks after the first dose, the humoral and cellular immunogenicity of the BNT162b2 mRNA vaccine (BioNTech/Pfizer) was suboptimal in COVID-19-naïve nursing home residents in comparison to COVID-19-naïve healthcare workers.

Moyo-Gwete T, Madzivhandila M, Makhado Z, et al. Cross-Reactive Neutralizing Antibody Responses Elicited by SARS-CoV-2 501Y.V2 (B.1.351). NEJM April 7, 2021. https://www.nejm.org/doi/full/10.1056/NEJMc2104192?query=featured_home

De la conception de vaccins efficaces sur les mutants.

Infection with B.1.351 (South Africa) elicits robust neutralizing antibody responses against P.1 (Brazil) and the original variants, which indicates high levels of cross-reactivity. Vaccines built on the spike protein of B.1.351 may be promising candidates for the elicitation of cross-reactive responses.

Lustig Y, Nemet I, Kliker L, et al. Neutralizing Response against Variants after SARS-CoV-2 Infection and One Dose of BNT162b2. NEJM April 7, 2021. https://www.nejm.org/doi/full/10.1056/NEJMc2104036?query=featured_home

De quoi rassurer celles et ceux qui ont été vaccinés par le Pfizer

In six HCW who had been infected with the original virus, one shot of BNT162b2 (BioNTech/Pfizer) induced robust neutralizing antibody responses against all variants of concern, including B.1.351 from South Africa.

9 avril 2021

Doria-Rose N, Suthar MS, Makowski M, et al. Antibody Persistence through 6 Months after the Second Dose of mRNA-1273 Vaccine for Covid-19. N Engl J Med. 2021 Apr 6. PubMed: https://pubmed.gov/33822494. https://www.nejm.org/doi/10.1056/NEJMc2103916

Immunité supérieure à 6 mois après deuxième injection de Moderna.

In 33 healthy adult participants in an ongoing Phase I trial, antibodies that were elicited by mRNA-1273 (Moderna) persisted through 6 months after the second dose, as detected by three distinct serologic assays.

Westhölter D, Taube C. SARS-CoV-2 outbreak in a long-term care facility after vaccination with BNT162b2. Clin Inf Dis April 7, 2021, ciab299. https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciab299/6213878?searchresult=1

Cluster et décès en établissement allemand après vaccination par Pfizer. Comme attendu, aucune protection un et quatre jours après la première injection.

What a disaster. In early January 2021, 73/76 (96%) residents and about 90% of the employees in an elderly care home in North-Rhine Westfalia, Germany, received a first dose of BNT162b2 (BioNTech/Pfizer). SARS-CoV-2 rapid antigen tests were all negative among residents and participating employees the day before. However, a member of the mobile vaccination team as well as an employee reported respiratory symptoms one and four days after vaccination respectively and tested positive for SARS-CoV-2 by PCR. Overall case fatality rate was 9/26 (35%).

7 avril 2021

Hippich M, Sifft P, Zapardiel-Gonzalo J, et al. A Public Health Antibody Screening Indicates a Marked Increase of SARS-CoV-2 Exposure Rate in Children during the Second Wave. Med April 02, 2021. https://www.cell.com/med/fulltext/S2666-6340(21)00121-5

Deuxième vague, enfants et Bavière.

In this large monitoring study from Bavaria, Germany, antibody frequencies in 2021 were eight-fold higher than those observed at the end of the first wave and remained three- to four-fold higher than the cumulative reported PCR positive frequencies in both pre-school and school children. Among the 413 PCR-positive children who completed questionnaires regarding symptoms, no symptoms were reported in 68% of antibody-positive pre-school children and in 52% of school children.

6 avril 2021

Hosp JA, Dressing A, Blazhenets G, et al. Cognitive impairment and altered cerebral glucose metabolism in the subacute stage of COVID-19. Brain April 3, 2021, awab009, https://academic.oup.com/brain/advance-article/doi/10.1093/brain/awab009/6209743?searchresult=1

Covid-19 et troubles cognitifs avec atteinte frontopariétale

Cognitive deficits are present in many COVID-19 patients requiring in-patient treatment. Of 15 patients undergoing extended neuropsychological testing, only two patients performed entirely normally. Orientation and language abilities were in the range of healthy subjects, while memory and executive items were most severely affected, making general deterioration unlikely. There was no decline in general attention or speed of processing. This specific pattern can hardly be explained by non-specific factors like fatigue. It also differs from cognitive impairment post-sepsis. Many patients displayed frontoparietal cognitive dysfunctions and 18FDG PET revealed pathological results in 10/15 patients with predominant frontoparietal hypometabolism.

5 avril 2021

Woolf SH, Chapman DA, Sabo RT. Excess Deaths From COVID-19 and Other Causes in the US, March 1, 2020, to January 2, 2021. JAMA April 2, 2021. https://jamanetwork.com/journals/jama/fullarticle/2778361?resultClick=1

Une simple "grippette" :

Between March 1, 2020, and January 2, 2021, the US experienced 2,801,439 deaths, 22.9% more than expected, representing 522,368 excess deaths. The 22.9% increase in all-cause mortality reported here far exceeds annual increases observed in recent years (≤ 2.5%). Deaths attributed to COVID-19 accounted for 72.4% of US excess deaths.

The SARS-CoV-2 variant with lineage B.1.351 clusters investigation team. Linked transmission chains of imported SARS-CoV-2 variant B.1.351 across mainland France, January 2021. Euro Surveill 2021;26(13):pii=2100333. https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2021.26.13.2100333

C'est gentil de ne pas répondre aux questions ! 

Two cases had travelled in mid-December 2020 with a group to Mozambique where they participated in a religious gathering and returned with the B.1.351 variant. A joint team of epidemiologists, public health workers and clinical and virological specialists co-operated across France to urgently investigate and initiate control measures. A total of 36 cases were analyzed. Believe it or not: “Another challenge was that some members of the clusters did not agree to answer questions”.

4 avril 2021

Cobey S, Larremore DB, Grad YH. et al. Concerns about SARS-CoV-2 evolution should not hold back efforts to expand vaccination. Nat Rev Immunol April 2, 2021. https://www.nature.com/articles/s41577-021-00544-9

La pression vaccinale compensée par son efficacité ?

Marc Lipsitch and colleagues argue that as long as vaccination provides some protection against escape variants, the corresponding reduction in prevalence and incidence should reduce the rate at which new variants are generated and the speed of adaptation.

Malhotra HS, Gupta P, Prabhu V. COVID-19 vaccination-associated myelitis. QJM 31 March 2021, hcab069, https://academic.oup.com/qjmed/advance-article/doi/10.1093/qjmed/hcab069/6206408?searchresult=1

Un nouvel effet adverse de l'AstraZeneca ?

A rare case of myelitis, seen with the ChAdOX1 nCoV-19 vaccine. On the 8th post-vaccination day, this 38 yr old man presented with abnormal sensations in both lower limbs.

2 avril 2021

Etude américaine sur les facteurs de risque d'infection, d'hospitalisation et de décès dans les établissements américains pour personnes âgées :

Surlignage et mise en exergue en rouge par l'auteur de ce blog :

RESULTS Among 482 323 long-stay residents included, the mean (SD) age was 82.7 (9.2) years, with 326 861 (67.8%) women, and 383 838 residents (79.6%) identifying as White. Among 137 119 residents (28.4%) diagnosed with SARS-CoV-2 during follow up, 29 204 residents (21.3%) were hospitalized, and 26 384 residents (19.2%) died within 30 days. Nursing homes explained 37.2% of the variation in risk of infection, while county explained 23.4%.

Risk of infection increased with increasing body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) (eg, BMI>45 vs BMI 18.5-25: adjusted hazard ratio [aHR], 1.19; 95% CI, 1.15-1.24) but varied little by other resident characteristics.

Risk of hospitalization after SARS-CoV-2 increased with increasing BMI (eg, BMI>45 vs BMI 18.5-25: aHR, 1.40; 95% CI, 1.28-1.52); male sex (aHR, 1.32; 95% CI, 1.29-1.35); Black (aHR, 1.28; 95% CI, 1.24-1.32), Hispanic (aHR, 1.20; 95% CI, 1.15-1.26), or Asian (aHR, 1.46; 95% CI, 1.36-1.57) race/ethnicity; impaired functional status (eg, severely impaired vs not impaired: aHR, 1.15; 95% CI, 1.10-1.22); and increasing comorbidities, such as renal disease (aHR, 1.21; 95% CI, 1.18-1.24) and diabetes (aHR, 1.16; 95% CI, 1.13-1.18).

Risk of mortality increased with age (eg, age >90 years vs 65-70 years: aHR, 2.55; 95% CI, 2.44-2.67), impaired cognition (eg, severely impaired vs not impaired: aHR, 1.79; 95% CI, 1.71-1.86), and functional impairment (eg, severely impaired vs not impaired: aHR, 1.94; 1.83-2.05).

Source : https://www.geriatrie-albi.com/mehta_2021.pdf

Jentsch PC, Anand M, Bauch CT. Prioritising COVID-19 vaccination in changing social and epidemiological landscapes: a mathematical modelling study. Lancet Inf Dis March 31, 2021. https://www.thelancet.com/action/showPdf?pii=S1473-3099%2821%2900057-8

The oldest-first strategy is not always the best option. This modelling study shows that in populations in which SARS-CoV-2 seropositivity is high, a contact-based strategy allocating vaccines according to the relative role played by different age groups in transmission may be more effective that targeting vulnerable groups.

Dejnirattisai W, Zhou D, Supasa P, et al. Antibody evasion by the P.1 strain of SARS-CoV-2. Cell March 30, 2021. https://www.cell.com/cell/fulltext/S0092-8674(21)00428-1

All new strains (P.1 from Brazil, B.1.351 from South Africa and B.1.1.7 from the UK) have mutations in the ACE2 binding site with P.1 and B.1.351 having a virtually identical triplet: E484K, K417N/T and N501Y, conferring similar increased affinity for ACE2. Surprisingly, P.1 was significantly less resistant to naturally acquired or vaccine induced antibody responses than B.1.351, suggesting that changes outside the receptor-binding domain impact neutralization.

Neutralization of P.1 and other variants by vaccine serum. (C) Pfizer vaccine, serum taken 7-17 days following the second dose (n = 25). (D) AstraZenca vaccine, serum taken 14 or 28 days following the second dose (n = 25).

Terminating the SARS-CoV-2 pandemic relies upon pan-global vaccination. Current vaccines elicit neutralizing antibody responses to the virus spike derived from early isolates. However, new strains have emerged with multiple mutations: P.1 from Brazil, B.1.351 from South Africa and B.1.1.7 from the UK (12, 10 and 9 changes in the spike respectively). All have mutations in the ACE2 binding site with P.1 and B.1.351 having a virtually identical triplet: E484K, K417N/T and N501Y, which we show confer similar increased affinity for ACE2. We show that, surprisingly, P.1 is significantly less resistant to naturally acquired or vaccine induced antibody responses than B.1.351 suggesting that changes outside the RBD impact neutralisation. Monoclonal antibody 222 neutralises all three variants despite interacting with two of the ACE2 binding site mutations, we explain this through structural analysis and use the 222 light chain to largely restore neutralization potency to a major class of public antibodies.

Ayoubkhani D, Khunti K, Nafilyan V, et al. Post-covid syndrome in individuals admitted to hospital with covid-19: retrospective cohort study. BMJ 2021;372: n693. 31 March 2021. https://www.bmj.com/content/372/bmj.n693

Le "Covid long"

47,780 hospitalized patients (mean age 65) discharged alive by 31 August 2020 were exactly matched to controls from a pool of about 50 million people in England for personal and clinical characteristics. Over a mean follow-up of 140 days, nearly a third were readmitted and more than 1 in 10 died after discharge, with these events occurring at rates four and eight times greater, respectively, than in the matched control group. Rates of multi-organ dysfunction after discharge were raised compared to the matched control group, suggesting extrapulmonary pathophysiology. As shown in the Figure, diabetes and major adverse cardiovascular event were particularly common.

1er avril 2021

Jagannathan P, Andrews JR, Bonilla H, et al. Peginterferon Lambda-1a for treatment of outpatients with uncomplicated COVID-19: a randomized placebo-controlled trial. Nat Commun March 30, 2021, 12, 1967. https://www.nature.com/articles/s41467-021-22177-1

Next disappointment: in this well-conducted, placebo-controlled RCT, a single dose of subcutaneous peg-interferon lambda-1a neither shortened the duration of SARS-CoV-2 viral shedding nor improved symptoms in out-patients with uncomplicated COVID-19.

aplan–Meier analyses of the primary and key secondary outcomes in the intention-to-treat population.

31 mars 2021

Pfizer et Moderna chez les professionnels de santé :

Thompson MG, Burgess JL, Naleway AL, et al. Interim Estimates of Vaccine Effectiveness of BNT162b2 and mRNA-1273 COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Health Care Personnel, First Responders, and Other Essential and Frontline Workers — Eight U.S. Locations, December 2020–March 2021. MMWR Morb Mortal Wkly Rep. ePub: 29 March 2021. https://www.cdc.gov/mmwr/volumes/70/wr/mm7013e3.htm

In this prospective cohort of 3950 health care personnel, first responders, and other essential and frontline workers who completed weekly SARS-CoV-2 testing for 13 consecutive weeks, mRNA vaccine effectiveness of full immunization (≥ 14 days after second dose) was 90% against SARS-CoV-2 infections regardless of symptom status; vaccine effectiveness of partial immunization (≥ 14 days after first dose but before second dose) was 80%.

30 mars 2021

By C. Hoffmann & B. S. Kamps
Copy-editor: Rob Camp

One year ago, we published the first edition of COVID Reference. It was a document on the fulminant accumulation of clinical knowledge about an emergent infectious disease in the previous three months. At that time, treatment strategies were tentative, the unutterable hydroxychloroquine was still en vogue, the multisystem inflammatory syndrome in children (MISC) as yet unheard of, and nobody knew about Long COVID or variants.

Since then, we have come a long way. An ultra-connected and worldwide cooperating science community has discovered – sometimes to their own surprise – how much they can achieve in a short time. Today, 15 months into the pandemic, more than 300 million people have been vaccinated. The development of these ultra-potent SARS-CoV-2 vaccines will be remembered as a milestone in medicine. They have opened new horizons and set a new benchmark for future pandemics.

29 mars 2021

Kupferschmidt K, Vogel G. A rare clotting disorder may cloud the world’s hopes for AstraZeneca’s COVID-19 vaccine. Science 2021, published 27 March. Full text: https://www.sciencemag.org/news/2021/03/rare-clotting-disorder-may-cloud-worlds-hopes-astrazenecas-covid-19-vaccine

https://gth-online.org/wp-content/uploads/2021/03/GTH_Stellungnahme_AstraZeneca_engl._3_22_2021.pdf

La physiopathologie des syndromes associant thromboses et hémorragies après vaccination AstraZeneca laisse penser que l'héparine et des immunoglobulines intraveineuses pourraient être utiles dans des conditions précises. Voir ci-dessus la publication de Kupferschmidt et celle d'Oldenburg et al. ci-dessous.

VIPIT – vaccine-induced prothrombotic immune thrombocytopenia – is a preliminary explanation for the unusual strokes and clotting disorders recorded in at least 30 recipients of the AstraZeneca vaccine. A summary.

Now, a group of researchers led by German clotting specialist Andreas Greinacher of the University of Greifswald says the highly unusual combination of symptoms—widespread blood clots and a low platelet count, sometimes with bleeding—resembles a rare side effect of the blood thinner heparin called heparin-induced thrombocytopenia (HIT).

In the event of side effects that persist or recur > 3 days after vaccination (e.g., dizziness; headache; visual disturbances; nausea / vomiting; shortness of breath; acute pain in chest, abdomen, or extremities), further medical diagnostics should be carried out to clarify a thrombosis. 

Références notables de bibliographie sur la Covid-19

Moschovis PP, Yonker LM, Shah J, et al. Aerosol transmission of SARS-CoV-2 by children and adults during the COVID-19 pandemic. Pediatric Pulmonology 2021. Full text: https://onlinelibrary.wiley.com/doi/epdf/10.1002/ppul.25330

The authors outline the major methods of transmission of SARS-CoV-2 focusing on aerosol transmission and reviewing the principles of aerosol science and discussing their implications for mitigating the spread of SARS-CoV-2.

Cliquer sur l'image pour l'agrandir :

Références notables de bibliographie sur la Covid-19

28 mars 2021

ANSM 20210326. Point de situation sur la surveillance des vaccins contre la COVID-19 – Période du 12/03/2021 au 18/03/2021. Agence nationale pour la sécurité du médicament et des produits de Santé 2021, published 26 March 2021. Full text: https://ansm.sante.fr/actualites/point-de-situation-sur-la-surveillance-des-vaccins-contre-la-covid-19-periode-du-12-03-2021-au-18-03-2021

On 26 March, the French National Medicine Safety Agency (Agence nationale pour la sécurité du médicament et des produits de Santé – ANSM) declared that there is a risk of atypical thrombosis associated with the AstraZeneca vaccine. The Agency reports 9 cases of big vein thromboses that are atypical by their location (mostly cerebral, but also digestive) and associated with thrombocytopenia and coagulation disorders. With some 1,430,000 injections of the AstraZeneca vaccine as of 18 March 2021, this is one case per 158,000 injections. These cases occurred within a median time of 8.5 days after vaccination in persons without particular risk factors (7 patients under 55 years of age, 2 more than 55 years). Between 12 and 18 March, two deaths were reported, including that of a medical student who died several days after being vaccinated. In the coming months of relative vaccine abundance, the AstraZeneca vaccine does not have a good star.

McEllistrem MC, Clancy CJ, Buehrle DJ, et al. Single dose of a mRNA SARS-CoV-2 vaccine is associated with lower nasopharyngeal viral load among nursing home residents with asymptomatic COVID-19. Clin Infect Dis 2021, published 26 March. Full text: https://doi.org/10.1093/cid/ciab263

In nursing home residents with asymptomatic COVID-19 diagnosed through twice-weekly surveillance testing, single dose BNT162b2 vaccination (Pfizer-BioNTech) was associated with -2.4 mean log10 lower nasopharyngeal viral load than that detected in absence of vaccination (p = 0.004).

27 mars 2021

Lefrancq N, Paireau J, Hozé N, et al. Evolution of outcomes for patients hospitalised during the first 9 months of the SARS-CoV-2 pandemic in France: A retrospective national surveillance data analysis. Lancet Regional Health, March 2021. Full-text: https://doi.org/10.1016/j.lanepe.2021.100087

Better get COVID-19 between waves when hospital capacities are not stretched to the limit. The authors find that both the probability of death and the probability of entering ICU were significantly correlated with COVID-19 ICU occupancy.

26 mars 2021

Stamatatos L, Czartoski J, Wan YH, et al. mRNA vaccination boosts cross-variant neutralizing antibodies elicited by SARS-CoV-2 infection. Science 2021, published 25 March. Full text: https://science.sciencemag.org/content/early/2021/03/24/science.abg9175

The preprint we presented on 10 February now published in Science. The study highlights the importance of vaccinating both uninfected and previously infected persons to elicit cross-variant neutralizing antibodies.

Janssen : apparemment efficace à 85% pour éviter les formes graves liées au variant sud-africain 501Y.V2

Source : Abdool Karim SS, de Oliveira T. New SARS-CoV-2 Variants — Clinical, Public Health, and Vaccine Implications. N Engl J Med 2021, published 24 March. Full text: https://doi.org/10.1056/NEJMc2100362

Cliquer sur l'image pour l'agrandir :

Références notables

25 mars 2021

Edara VV, Norwood C, Floyd K, et al. Infection and vaccine-induced antibody binding and neutralization of the B.1.351 SARS-CoV-2 variant. Cell Host Microbe 2021, published 20 March. Full text: https://doi.org/10.1016/j.chom.2021.03.009

Despite reduced antibody titers against the B.1.351 variant (first detected in South Africa), sera from infected and vaccinated individuals containing polyclonal antibodies to the spike protein could still neutralize SARS-CoV-2 B.1.351. The authors conclude that protective humoral immunity may be retained against this variant.

24 mars 2021

Benedict C, Cedernaes J. Could a good night’s sleep improve COVID-19 vaccine efficacy? Lancet Respir Med. 2021 Mar 12:S2213-2600(21)00126-0. PubMed: https://pubmed.gov/33721558. Full text: https://doi.org/10.1016/S2213-2600(21)00126-0

Could the timing of vaccination affect the immune response to COVID-19 vaccines? Should we all take a nap after vaccination? It wouldn’t do any harm.

Figure. Post-vaccination sleep and morning timing of vaccination as possible immune adjuvants for COVID-19 vaccination

23 mars 2021

Hoffmann M, Arora P, Groß R, et al. SARS-CoV-2 variants B.1.351 and P.1 escape from neutralizing antibodies. Cell 2021, accepted 16 March. Full-text: https://doi.org/10.1016/j.cell.2021.03.036

The authors show that entry of all variants into human cells is susceptible to blockade by the entry inhibitors soluble ACE2, Camostat, EK-1 and EK-1-C4. In contrast, entry of B.1.351 and P.1 was partially (casirivimab) or fully (bamlanivimab) resistant to monoclonal antibodies. Moreover, entry of these variants was less efficiently inhibited by plasma from convalescent COVID-19 patients and sera from individuals vaccinated with the Pfizer-BioNTech vaccine.

Khoury DS, Cromer D, Reynaldi A, et al. What level of neutralising antibody protects from COVID-19? medRxiv 2021, posted 11 March. Full-text: https://doi.org/10.1101/2021.03.09.21252641

Predictive models of immune protection are useful to identify immune correlates of protection to assist in the future deployment of vaccines. Here, the authors modelled the relationship between in vitro neutralisation levels and observed protection from SARS-CoV-2 infection using data from seven current vaccines as well as convalescent cohorts. They report that neutralisation level is highly predictive of immune protection. Attention: this is a pre-print, so don’t take the data for granted. However, in the future, with vaccines abundantly available, we will use figures such as Figure 1 to decide whether to prefer product A over product B.

Références notables

22 mars 2021

Adlhoch C, Mook P, Lamb F, et al. Very little influenza in the WHO European Region during the 2020/21 season, weeks 40 2020 to 8 2021. Eurosurveillance 18 March 2021, Volume 26, Issue 11. https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2021.26.11.2100221

Almost no flu this year. This 2020/21 influenza season is exceptional since the creation of the Global Influenza Surveillance and Response System (GISRS) network in 1952. Positivity was 0.1% (33/25,606) this season compared to an average positivity of 38% (14,966/39,407) between week 40 year X and week 8 the following year. Yes, this was statistically significant.

21 mars 2021

Hassan AO, Feldmann F, Zhao H, et al. A single intranasal dose of chimpanzee adenovirus-vectored vaccine protects against SARS-CoV-2 infection in rhesus macaques. Cell Rep Med March 17, 2021. https://www.cell.com/action/showPdf?pii=S2666-3791%2821%2900046-X

The future? An intranasally-administered chimpanzee adenovirus-vectored vaccine encoding a pre-fusion stabilized spike (S) protein (ChAd-SARS-CoV-2-S) worked well in macaques. A single intranasal dose induced neutralizing antibodies and T cell responses and limited or prevented infection in the upper and lower respiratory tract after a SARS-CoV-2 challenge.

20 mars 2021

Grint DJ, Wing K, Williamson E, et al. Case fatality risk of the SARS-CoV-2 variant of concern B.1.1.7 in England, 16 November to 5 February. Volume 26, Issue 11, 18 March 2021. https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2021.26.11.2100256

Evidence grows that B.1.1.7 is more dangerous. In this data drawn from the OpenSAFELY electronic health records secure research platform (covering 40% of England’s population registered with a general practitioner), there was a consistently higher (about two thirds) absolute risk of death by 28 days after a SARS-CoV-2-positive test in all groups stratified by age, sex and presence of co-morbidities

19 mars 2021 

Jevalikar G, Mithal A, Singh A, et al. Lack of association of baseline 25-hydroxyvitamin D levels with disease severity and mortality in Indian patients hospitalized for COVID-19. Sci Rep 11, 6258 (2021). https://www.nature.com/articles/s41598-021-85809-y

Oh, again, no effect of vitamin D. In this prospective observational study on 404 patients, serum 25-OHD levels at admission did not correlate with inflammatory markers, clinical outcomes, or mortality in hospitalized COVID-19 patients. Treatment of vitamin D deficiency with cholecalciferol did not make any difference to the outcomes.

18 mars 2021 

Mahdi SA, Baillie C, Cutland CL, et al. Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. NEJM, March 16, 2021. https://www.nejm.org/doi/full/10.1056/NEJMoa2102214

No protection from mild-to-moderate COVID-19 with AstraZeneca in this large RCT on young (median age 30 years), HIV-negative patients in South Africa. Infections were seen in 23 of 717 placebo recipients (3.2%) and in 19 of 750 vaccine recipients (2.5%), for an efficacy of 21.9% (95% CI, −49.9 to 59.8). Main caveat: as there were no cases of hospitalization in the study, it remains unclear whether ChAdOx1 nCov-19 may protect against severe infection with the B.1.351 variant.

Publié dans Covid-19, bibliographie

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