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1.
JAMA Network Open ; 5(9):e2231778, 2022.
Article in English | MEDLINE | ID: covidwho-2027280

ABSTRACT

Importance: The BNT162b2 two-dose vaccine (BioNTech/Pfizer) has high effectiveness that wanes within several months. The third dose is effective in mounting a significant immune response, but its durability is unknown. Objective: To compare antibody waning after second and third doses and estimate the association of antibody kinetics with susceptibility to infection with the Omicron variant of SARS-CoV-2. Design, Setting, and Participants: In a prospective longitudinal cohort study in a tertiary medical center in Israel, health care workers who received the BNT162b2 vaccine were followed up monthly for IgG and neutralizing antibody levels. Linear mixed models were used to compare antibody titer waning of second and third doses and to assess whether antibody dynamics were associated with Omicron transmission. Avidity, T cell activation, and microneutralization of sera against different variants of concern were assessed for a subgroup. Exposure: Vaccination with a booster dose of the BNT162b2 vaccine. Main Outcomes and Measures: The primary outcome was the rate of antibody titer change over time, and the secondary outcome was SARS-CoV-2 Omicron variant infection, as confirmed by reverse transcriptase-polymerase chain reaction. Results: Overall, 4868 health care workers (mean [SD] age, 46.9 [13.7] years;3558 [73.1%] women) and 3972 health care workers (mean [SD] age, 48.5 [14.1] years;996 [74.9%] women) were followed up for 5 months after their second and third vaccine doses, respectively. Waning of IgG levels was slower after the third compared with the second dose (1.32%/d [95% CI, 1,29%/d to 1.36%/d] vs 2.26% [95% CI, 2.13%/d 2.38%/d]), as was waning of neutralizing antibody levels (1.32%/d [95% CI, 1.21%/d to 1.43%/d] vs 3.34%/d [95% CI, 3.11%/d to 3.58%/d]). Among 2865 health care workers assessed for Omicron incidence during an additional 2 months of follow-up, lower IgG peak (ratio of means 0.86 [95% CI, 0.80-0.91]) was associated with Omicron infection, and among participants aged 65 years and older, faster waning of IgG and neutralizing antibodies (ratio of mean rates, 1.40;[95% CI, 1.13-1.68] and 3.58 [95% CI, 1.92-6.67], respectively) were associated with Omicron infection. No waning in IgG avidity was observed 112 days after the third dose. Live neutralization of Omicron was lower compared with previous strains, with a geometric mean titer at the peak of 111 (95% CI, 75-166), compared with 942 (95% CI, 585-1518) for WT, 410 (95% CI, 266-634) for Delta;it demonstrated similar waning to 26 (95% CI, 16-42) within 4 months. Among 77 participants tested for T cell activity, mean (SD) T cell activity decreased from 98 (5.4) T cells/106 peripheral blood mononuclear cells to 59 (9.3) T cells/106 peripheral blood mononuclear cells. Conclusions and Relevance: This study found that the third vaccine dose was associated with greater durability than the second dose;however, Omicron was associated with greater resistance to neutralization than wild type and Delta variants of concern. Humoral response dynamics were associated with susceptibility to Omicron infection.

3.
Frontiers in Biological Detection: From Nanosensors to Systems XIV 2022 ; 11979, 2022.
Article in English | Scopus | ID: covidwho-1891711

ABSTRACT

The COVID-19 pandemic demands fast, sensitive, and specific diagnostic tools for virus surveillance and containment. Current methods for diagnosing the COVID-19 are based on direct detection of either viral antigens or viral ribonucleic acids (RNA) in swab samples. Antigen-targeting tests are simple, have fast turnaround times, and allow rapid testing. Unfortunately, compared with viral RNA-targeting tests, their sensitivity is low, especially during the initial stages of the disease, which limits their adoption and implementation. Direct detection of SARS-CoV-2 RNA using reversetranscription quantitative polymerase chain reaction (RT-qPCR) is sensitive and specific, making it a golden standard in SARS-CoV-2 detection. However, it had not seen a significant update since its introduction three decades ago. It has a long turnaround time, requires a high number of amplification cycles, and a complicated and expensive detection system for real-time monitoring of the signal. While insignificant for research applications, these limitations present severe problems for mass testing required to contain the disease. Here, we introduce a diagnostic platform for rapid and highly sensitive clinical diagnosis of COVID-19. Based on the biochemical principles of the RT-PCR, it utilizes the endpoint detection by the magnetic modulation biosensing (MMB) system, allowing the detection of as little as two copies of SARS-CoV-2 in ∼30 minutes. Testing 309 RNA samples from verified SARS-CoV-2 carriers and healthy subjects resulted in 97.8% sensitivity, 100% specificity, and 0% crossreactivity. This level of performance is on par with the gold standard (RT-qPCR) but requires 1/3 of the time. The platform can be easily adapted to detect almost any other pathogen of choice. © COPYRIGHT SPIE. Downloading of the is permitted for personal use only.

4.
O'Toole, A.; Hill, V.; Pybus, O. G.; Watts, A.; Bogoch, II, Khan, K.; Messina, J. P.; consortium, Covid- Genomics UK, Network for Genomic Surveillance in South, Africa, Brazil, U. K. Cadde Genomic Network, Tegally, H.; Lessells, R. R.; Giandhari, J.; Pillay, S.; Tumedi, K. A.; Nyepetsi, G.; Kebabonye, M.; Matsheka, M.; Mine, M.; Tokajian, S.; Hassan, H.; Salloum, T.; Merhi, G.; Koweyes, J.; Geoghegan, J. L.; de Ligt, J.; Ren, X.; Storey, M.; Freed, N. E.; Pattabiraman, C.; Prasad, P.; Desai, A. S.; Vasanthapuram, R.; Schulz, T. F.; Steinbruck, L.; Stadler, T.; Swiss Viollier Sequencing, Consortium, Parisi, A.; Bianco, A.; Garcia de Viedma, D.; Buenestado-Serrano, S.; Borges, V.; Isidro, J.; Duarte, S.; Gomes, J. P.; Zuckerman, N. S.; Mandelboim, M.; Mor, O.; Seemann, T.; Arnott, A.; Draper, J.; Gall, M.; Rawlinson, W.; Deveson, I.; Schlebusch, S.; McMahon, J.; Leong, L.; Lim, C. K.; Chironna, M.; Loconsole, D.; Bal, A.; Josset, L.; Holmes, E.; St George, K.; Lasek-Nesselquist, E.; Sikkema, R. S.; Oude Munnink, B.; Koopmans, M.; Brytting, M.; Sudha Rani, V.; Pavani, S.; Smura, T.; Heim, A.; Kurkela, S.; Umair, M.; Salman, M.; Bartolini, B.; Rueca, M.; Drosten, C.; Wolff, T.; Silander, O.; Eggink, D.; Reusken, C.; Vennema, H.; Park, A.; Carrington, C.; Sahadeo, N.; Carr, M.; Gonzalez, G.; Diego, Search Alliance San, National Virus Reference, Laboratory, Seq, Covid Spain, Danish Covid-19 Genome, Consortium, Communicable Diseases Genomic, Network, Dutch National, Sars-CoV-surveillance program, Division of Emerging Infectious, Diseases, de Oliveira, T.; Faria, N.; Rambaut, A.; Kraemer, M. U. G..
Wellcome Open Research ; 6:121, 2021.
Article in English | MEDLINE | ID: covidwho-1450989

ABSTRACT

Late in 2020, two genetically-distinct clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with mutations of biological concern were reported, one in the United Kingdom and one in South Africa. Using a combination of data from routine surveillance, genomic sequencing and international travel we track the international dispersal of lineages B.1.1.7 and B.1.351 (variant 501Y-V2). We account for potential biases in genomic surveillance efforts by including passenger volumes from location of where the lineage was first reported, London and South Africa respectively. Using the software tool grinch (global report investigating novel coronavirus haplotypes), we track the international spread of lineages of concern with automated daily reports, Further, we have built a custom tracking website (cov-lineages.org/global_report.html) which hosts this daily report and will continue to include novel SARS-CoV-2 lineages of concern as they are detected.

5.
Israel Medical Association Journal ; 23(1):7-10, 2021.
Article in English | Web of Science | ID: covidwho-1161475

ABSTRACT

Background: During the coronavirus disease-2019 (COVID-19) pandemic outbreak our blood bank developed protocols to guarantee accurate blood components to COVID-19 patients. Objectives: To provide convalescent whole blood donor screening strategies for patients recovering from COVID-19. Methods: We recruited COVID-19 recovering patients who met our defined inclusion criteria for whole blood donation. All blood units were screened for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA by real time reverse transcription polymerase chain reaction (RT-PCR) and SARS-COV-2 immunoglobutin G (IgG) antibodies against the S1 domain. Results: We screened 180 blood units from patients recovering from COVID-19. All results were negative for SARS-CoV-2 RNA and 87.2% were positive for SARS-COV-2 IgG antibodies in the plasma. Conclusions: Blood component units from recovering COVID-19 patients are safe. Plasma units with positive IgG antibodies could serve as an efficient passive immunization for COVID-19 patients. Moreover, in the face of increased transfusion demand for treatment of anemia and coagulation dysfunction in critical ill COVID-19 patients, red blood cells units and random platelets units from convalescent donors can be safely transfused.

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