JAMA: Patients can gain super immunity after breakthrough new coronavirus infection

There are more and more reports of breakthrough infections after SARS-CoV-2 vaccination, which may be due to the decrease in antibody levels induced by the vaccine
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In addition, emerging variants with reduced sensitivity to vaccine-induced antibodies are responsible for most new cases
.

The focus of the research is to determine the vaccine breakthrough rate based on antibody levels after standard vaccination practices
.

We evaluated the level of antibodies and cross-neutralization of mutations after breakthrough infection
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This research has just been published in the latest issue of JAMA
.

Between January 31, 2021 and August 18, 2021, breakthrough infections were recruited at Oregon Health and Science University
.

Patients are diagnosed with breakthrough infections based on PCR methods
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The control is a fully vaccinated individual without breakthrough infection
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Matched by gender, age, time between vaccinations, and time between sample collection and the most recent antigen exposure (PCR confirmation of people with breakthrough infection and final vaccine dose of the control)
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Sequencing of the full-length viral genome is used to identify SARS-CoV-2 variants
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The enzyme-linked immunosorbent assay was used to determine the serum dilution titer, where 50% effective concentration (EC50) of IgG, IgA, and IgM antibodies are specific to the SARS-CoV-2 spike receptor binding domain
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Determine the live SARS-CoV-2 neutralizing serum by performing a 50% focal reduction neutralization test (FRNT50) against isolates of the original SARS-CoV-2 strain (WA1) and related variants (Alpha, Beta, Gamma, and Delta) Dilution titer
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The median breakthrough and control serum values ​​were calculated in GraphPad Prism and compared with the Wilcoxon paired signed-rank test with Holm-Šídák correction
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The neutralizing titers of Delta and WA1 of the Delta mutation breakthrough cases, non-Delta breakthrough cases and the control confirmed by comparing the sequence, the Kruskal-Wallis test with Dunn's correction is used to determine the neutralizing potency of Delta
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The results showed that a total of 26 breakthrough infection subjects (mean age, 38 years; 20 [77%] women; 24 [92%] were vaccinated with BNT162b2, with a median of 28 days and 28 days after the PCR date.
Sampling was taken 213.
5 days after the final vaccination; 21 [81%]] and 26 controls (average age 39 years; 21 [81%] females; 26 [100%] were vaccinated with BNT162b2, taking samples 28 days after the final vaccination on average )
.

total breakthrough infection receptor binding domain participant specific immunoglobulin increases, EC50 median of 2152 (95% CI, 961-3596) , while the control group was 668 (95% CI, 473-892) (Increase 322%; P <0.
001) (Figure 1A)
.

The median serum dilution of IgG and IgA both increased
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The median IgA EC50 after breakthrough infection was 120 (95% CI, 44-246), while the control group was 24 (95% CI, 24-24) (an increase of 502%; P <.
001)
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There were no significant differences in IgM levels between the groups
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Among the breakthrough cases confirmed in the sequence, 10 cases were Delta infections and 9 cases were non-Delta infections
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In breakthrough cases, the median FRNT50 for WA1 was 4646 (95% CI, 2283-7053), while the control group was 489 (95% CI, 272-822) (950% increase; P <.
001)
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 The FRNT50 results for Alpha, Beta, and Gamma variants are shown in Figure 2A
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In breakthrough cases, the median FRNT50 for the Delta variant was 2482 (95% CI, 1072-4923), while the control was 243 (95% CI, 118-336) (1021% increase; P <.
001) The serum from Delta breakthrough cases is more effective against Delta variants, and the WA1 neutralization rate of each participant is 99% (95% CI, 73-151), compared with 36% (95% CI, 33-151) for non-Delta cases.
52) and 41% (95% CI, 24-56) were controls (Figure 2B)
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The results of this study showed that despite the main mild disease, humoral immunity was significantly enhanced after breakthrough infection, especially IgA, which may be due to the different exposure routes between vaccination and natural infection
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In addition, breakthrough sera showed improved cross-neutralization of mutations, especially Delta breakthrough infection showed higher efficacy on Delta, which shows that through the development of variant enhancers with antigen inserts that match the emerging SARS-CoV , Can expand the protective immune response
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Of course, the limitations of this study include the small number of samples and the difference in the time from initial vaccination to serum collection between the breakthrough group and the control group.
Emerging evidence suggests that this may contribute to the development of variant cross-neutralizing antibody responses
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In addition, Metz Medical believes that whether breakthrough infections are equally effective for Omi Keron requires further research
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Original source: Bates TA, McBride SK, Winders B, Schoen D, Trautmann L, Curlin ME, Tafesse FG.
Antibody Response and Variant Cross-Neutralization After SARS-CoV-2 Breakthrough Infection.
JAMA.
2021 Dec 16.
doi: 10.
1001/ Written by jama.
2021.
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