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2.
N Engl J Med ; 387(3): 227-236, 2022 07 21.
Article in English | MEDLINE | ID: covidwho-1908352

ABSTRACT

BACKGROUND: Limited evidence is available on the real-world effectiveness of the BNT162b2 vaccine against coronavirus disease 2019 (Covid-19) and specifically against infection with the omicron variant among children 5 to 11 years of age. METHODS: Using data from the largest health care organization in Israel, we identified a cohort of children 5 to 11 years of age who were vaccinated on or after November 23, 2021, and matched them with unvaccinated controls to estimate the vaccine effectiveness of BNT162b2 among newly vaccinated children during the omicron wave. Vaccine effectiveness against documented severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and symptomatic Covid-19 was estimated after the first and second vaccine doses. The cumulative incidence of each outcome in the two study groups through January 7, 2022, was estimated with the use of the Kaplan-Meier estimator, and vaccine effectiveness was calculated as 1 minus the risk ratio. Vaccine effectiveness was also estimated in age subgroups. RESULTS: Among 136,127 eligible children who had been vaccinated during the study period, 94,728 were matched with unvaccinated controls. The estimated vaccine effectiveness against documented infection was 17% (95% confidence interval [CI], 7 to 25) at 14 to 27 days after the first dose and 51% (95% CI, 39 to 61) at 7 to 21 days after the second dose. The absolute risk difference between the study groups at days 7 to 21 after the second dose was 1905 events per 100,000 persons (95% CI, 1294 to 2440) for documented infection and 599 events per 100,000 persons (95% CI, 296 to 897) for symptomatic Covid-19. The estimated vaccine effectiveness against symptomatic Covid-19 was 18% (95% CI, -2 to 34) at 14 to 27 days after the first dose and 48% (95% CI, 29 to 63) at 7 to 21 days after the second dose. We observed a trend toward higher vaccine effectiveness in the youngest age group (5 or 6 years of age) than in the oldest age group (10 or 11 years of age). CONCLUSIONS: Our findings suggest that as omicron was becoming the dominant variant, two doses of the BNT162b2 messenger RNA vaccine provided moderate protection against documented SARS-CoV-2 infection and symptomatic Covid-19 in children 5 to 11 years of age. (Funded by the European Union through the VERDI project and others.).


Subject(s)
BNT162 Vaccine , COVID-19 , SARS-CoV-2 , Vaccine Efficacy , BNT162 Vaccine/therapeutic use , COVID-19/epidemiology , COVID-19/prevention & control , Child , Child, Preschool , Humans , Israel/epidemiology , SARS-CoV-2/drug effects , Vaccine Efficacy/statistics & numerical data , Vaccines, Synthetic/therapeutic use , mRNA Vaccines/therapeutic use
3.
N Engl J Med ; 387(2): 109-119, 2022 07 14.
Article in English | MEDLINE | ID: covidwho-1900734

ABSTRACT

BACKGROUND: Infants younger than 6 months of age are at high risk for complications of coronavirus disease 2019 (Covid-19) and are not eligible for vaccination. Transplacental transfer of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after maternal Covid-19 vaccination may confer protection against Covid-19 in infants. METHODS: We used a case-control test-negative design to assess the effectiveness of maternal vaccination during pregnancy against hospitalization for Covid-19 among infants younger than 6 months of age. Between July 1, 2021, and March 8, 2022, we enrolled infants hospitalized for Covid-19 (case infants) and infants hospitalized without Covid-19 (control infants) at 30 hospitals in 22 states. We estimated vaccine effectiveness by comparing the odds of full maternal vaccination (two doses of mRNA vaccine) among case infants and control infants during circulation of the B.1.617.2 (delta) variant (July 1, 2021, to December 18, 2021) and the B.1.1.259 (omicron) variant (December 19, 2021, to March 8, 2022). RESULTS: A total of 537 case infants (181 of whom had been admitted to a hospital during the delta period and 356 during the omicron period; median age, 2 months) and 512 control infants were enrolled and included in the analyses; 16% of the case infants and 29% of the control infants had been born to mothers who had been fully vaccinated against Covid-19 during pregnancy. Among the case infants, 113 (21%) received intensive care (64 [12%] received mechanical ventilation or vasoactive infusions). Two case infants died from Covid-19; neither infant's mother had been vaccinated during pregnancy. The effectiveness of maternal vaccination against hospitalization for Covid-19 among infants was 52% (95% confidence interval [CI], 33 to 65) overall, 80% (95% CI, 60 to 90) during the delta period, and 38% (95% CI, 8 to 58) during the omicron period. Effectiveness was 69% (95% CI, 50 to 80) when maternal vaccination occurred after 20 weeks of pregnancy and 38% (95% CI, 3 to 60) during the first 20 weeks of pregnancy. CONCLUSIONS: Maternal vaccination with two doses of mRNA vaccine was associated with a reduced risk of hospitalization for Covid-19, including for critical illness, among infants younger than 6 months of age. (Funded by the Centers for Disease Control and Prevention.).


Subject(s)
COVID-19 Vaccines , COVID-19 , Hospitalization , Pregnancy Complications, Infectious , mRNA Vaccines , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/therapeutic use , Female , Hospitalization/statistics & numerical data , Humans , Infant , Mothers , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/prevention & control , SARS-CoV-2 , Vaccination/statistics & numerical data , Vaccines, Synthetic , mRNA Vaccines/adverse effects , mRNA Vaccines/therapeutic use
5.
Cell Rep ; 39(2): 110680, 2022 04 12.
Article in English | MEDLINE | ID: covidwho-1814235

ABSTRACT

Knowledge about the impact of prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection of the elderly on mRNA vaccination response is needed to appropriately address the demand for additional vaccinations in this vulnerable population. Here, we show that octogenarians, a high-risk population, mount a sustained SARS-CoV-2 spike-specific immunoglobulin G (IgG) antibody response for 15 months following infection. This response boosts antibody levels 35-fold upon receiving a single dose of BNT162b2 mRNA vaccine 15 months after recovery from coronavirus disease 2019 (COVID-19). In contrast, antibody responses in naive individuals boost only 6-fold after a second vaccine. Spike-specific angiotensin-converting enzyme 2 (ACE2) antibody binding responses in the previously infected octogenarians following two vaccine doses exceed those found in a naive cohort after two doses. RNA sequencing (RNA-seq) demonstrates activation of interferon-induced genetic programs, which persist only in the previously infected. A preferential increase of specific immunoglobulin G heavy chain variable (IGHV) clonal transcripts that are the basis of neutralizing antibodies is observed only in the previously infected nuns.


Subject(s)
Antibody Formation , COVID-19 , SARS-CoV-2 , mRNA Vaccines , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antibody Formation/immunology , BNT162 Vaccine , COVID-19/immunology , COVID-19/prevention & control , COVID-19/virology , Humans , Immunoglobulin G , Octogenarians , RNA, Messenger/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus , Vaccination , Vaccines, Synthetic , mRNA Vaccines/therapeutic use
6.
Cell Rep Med ; 3(5): 100631, 2022 05 17.
Article in English | MEDLINE | ID: covidwho-1799660

ABSTRACT

Two doses of Pfizer/BioNTech BNT162b2 mRNA vaccine elicit robust severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibodies with frequent adverse events. Here, by applying a high-dimensional immune profiling on 92 vaccinees, we identify six vaccine-induced immune dynamics that correlate with the amounts of neutralizing antibodies, the severity of adverse events, or both. The early dynamics of natural killer (NK)/monocyte subsets (CD16+ NK cells, CD56high NK cells, and non-classical monocytes), dendritic cell (DC) subsets (DC3s and CD11c- Axl+ Siglec-6+ [AS]-DCs), and NKT-like cells are revealed as the distinct cell correlates for neutralizing-antibody titers, severity of adverse events, and both, respectively. The cell correlates for neutralizing antibodies or adverse events are consistently associated with elevation of interferon gamma (IFN-γ)-inducible chemokines, but the chemokine receptors CCR2 and CXCR3 are expressed in distinct manners between the two correlates: vaccine-induced expression on the neutralizing-antibody correlate and constitutive expression on the adverse-event correlate. The finding may guide vaccine strategies that balance immunogenicity and reactogenicity.


Subject(s)
BNT162 Vaccine , COVID-19 , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , BNT162 Vaccine/adverse effects , BNT162 Vaccine/immunology , BNT162 Vaccine/therapeutic use , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , COVID-19 Vaccines/therapeutic use , Humans , SARS-CoV-2/genetics , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology , Vaccines, Synthetic/therapeutic use , mRNA Vaccines/adverse effects , mRNA Vaccines/immunology , mRNA Vaccines/therapeutic use
7.
Eur J Clin Invest ; 52(2): e13713, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1541727

ABSTRACT

BACKGROUND: COVID-19 and some anti-SARS-CoV-2 vaccines trigger a humoral autoimmune response against a broad range of endogenous components, which may affect recipients' prognosis in predisposed individuals. Autoantibodies directed against apolipoprotein A-1 (AAA1 IgG) the major protein fraction of High Density Lipoprotein have been shown to be raised in COVID-19 and in rheumatoid arthritis (RA) patients and other populations where they have been associated with poorer outcomes. We wanted to assess the impact of anti-SARS-CoV-2 mRNA-based vaccination on AAA1 autoimmune biomarkers in RA patients. METHODS: 20 healthy controls and 77 RA mRNA-based vaccinated patients were collected at baseline, 3 weeks after the first vaccination, 2 and 8 weeks after the second vaccination. AAA1 and SARS-CoV-2 serologies were measured by immunoassays. Systemic and local symptoms occurring during the vaccination protocol were recorded. RESULTS: mRNA-based vaccination induced a significant increase in median AAA1 IgG levels in both healthy controls and RA patients overtime. However, in both populations, these medians trend did not translate into significant increase in AAA1 IgG seropositivity rates despite evolving from 5 to 10% in healthy controls, and from 9 to 12.9% in RA patients. No associations were retrieved between AAA1 IgG and symptoms of any kind during the vaccination protocol. CONCLUSIONS: mRNA-based vaccination seems to induce a light AAA1 IgG response in immunocompetent individuals within 2 months after the last injection. Although we did not observe any warning signs, the formal demonstration of the harmlessness of such biological warrants further studies.


Subject(s)
Apolipoprotein A-I/immunology , Arthritis, Rheumatoid/immunology , Autoantibodies/immunology , COVID-19 Vaccines/adverse effects , COVID-19/prevention & control , Immunity, Humoral/immunology , mRNA Vaccines/adverse effects , 2019-nCoV Vaccine mRNA-1273/adverse effects , 2019-nCoV Vaccine mRNA-1273/therapeutic use , Adult , Aged , BNT162 Vaccine/adverse effects , BNT162 Vaccine/therapeutic use , COVID-19/immunology , COVID-19 Vaccines/therapeutic use , Case-Control Studies , Female , Humans , Immunocompetence , Immunoglobulin G , Male , Middle Aged , SARS-CoV-2 , mRNA Vaccines/therapeutic use
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