medRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2022,
Volume and Issue:
unknown
Published: Jan. 28, 2022
Recognizing
that
anti-SARS-CoV-2
antibody
levels
wane
over
time
following
the
2-dose
SARS-CoV-2
mRNA
series,
FDA
approved
a
booster
dose
for
people
greater
than
12
years
old.
Limited
data
exist
on
whether
of
vaccine
results
in
protection
primary
series.
We
examined
total
and
neutralizing
antibodies
to
spike
protein
SARS-CoV-2,
against
Washington-1
(WA-1)
variants
concern
(VOC)
including
Beta,
Delta
Omicron
longitudinal
cohort.
Healthcare
workers
(HWs)
were
included
analysis
if
serum
was
collected
1)
within
14-44
days
post-dose2
an
(Timepoint
1,
TP1),
or
2)
at
least
8
months
2,
TP2),
3)
3,
TP3).
HWs
with
prior
covid-positive
PCR
excluded.
found
there
is
little
no
capability
series
omicron
variant,
capacity
any
variant
strain
tested
has
been
lost
by
8-months
post
two-dose
vaccination
However,
eliminates
immune
escape
observed
Neutralizing
titers
significantly
higher
all
post-boost
compared
The
nature
our
cohort
facilitated
paired
samples
pre
boost,
showing
15-fold
increase
neutralization
these
samples.
An
provides
quantity
quality
regimen
critical
provide
variant.
Vaccines,
Journal Year:
2024,
Volume and Issue:
12(3), P. 241 - 241
Published: Feb. 26, 2024
In
all
pivotal
trials
of
COVID-19
vaccines,
the
history
previous
SARS-CoV-2
infection
was
mentioned
as
one
main
exclusion
criteria.
absence
clinical
trials,
observational
studies
are
primary
source
for
evidence
generation.
This
study
aims
to
describe
patient-reported
adverse
drug
reactions
(ADRs)
following
first
vaccination
cycle,
well
administration
booster
doses
different
vaccine
brands,
in
people
with
prior
infection,
compared
infection-free
matched
cohorts
vaccinees.
A
web-based
prospective
conducted
collecting
vaccinee-reported
outcomes
through
electronic
questionnaires
from
eleven
European
countries
period
February
2021–February
2023.
baseline
questionnaire
and
up
six
follow-up
collected
data
on
vaccinee’s
characteristics,
solicited
unsolicited
reactions.
Overall,
3886
902
vaccinees
having
received
dose
or
a
dose,
respectively,
were
included
analysis.
After
reported
at
least
ADR
higher
frequency
than
those
without
(3470
[89.6%]
vs.
2916
[75.3%],
614
[68.2%]
546
[60.6%],
respectively).
On
contrary
side,
after
second
lower
frequency,
controls
(1443
[85.0%]
1543
[90.9%]).
The
median
time
onset
recovery
similar
across
cohorts.
individuals
who
Vaxzevria
Spikevax
doses.
serious
ADRs
low
Data
this
large-scale
could
be
used
inform
likelihood
effects
based
their
age,
sex,
type
administered.
line
safety
profile
vaccines
also
confirmed
infection.
The Lancet Infectious Diseases,
Journal Year:
2022,
Volume and Issue:
23(3), P. 295 - 306
Published: Oct. 20, 2022
BackgroundCOVID-19
vaccine
rollout
is
lagging
in
Africa,
where
there
has
been
a
high
rate
of
SARS-CoV-2
infection.
We
aimed
to
evaluate
the
effect
infection
before
vaccination
with
ChAdOx-nCoV19
(AZD1222)
on
antibody
responses
through
180
days.MethodsWe
did
an
unmasked
post-hoc
immunogenicity
analysis
after
first
and
second
doses
AZD1222
randomised,
placebo-controlled,
phase
1b–2a
study
done
seven
locations
South
Africa.
recipients
who
were
HIV-uninfected,
stratified
into
baseline
seropositive
or
seronegative
groups
using
serum
anti-nucleocapsid
(anti-N)
immunoglobulin
G
(IgG)
electroluminescence
immunoassay
establish
dose
AZD1222.
Binding
IgG
spike
(anti-S)
receptor
binding
domain
(anti-RBD)
measured
(day
0),
28),
day
42,
180.
Neutralising
(NAb)
against
variants
D614G,
beta,
delta,
gamma,
A.VOI.V2,
omicron
BA1
BA.4
variants,
by
pseudovirus
assay
28,
180).
This
trial
registered
ClinicalTrials.gov,
NCT04444674,
Pan
African
Clinicals
Trials
Registry,
PACTR202006922165132.FindingsOf
185
individuals
randomly
assigned
AZD1222,
we
included
91
58
seronegative,
final
analysis.
In
group,
was
little
change
anti-S
(and
anti-RBD
IgG)
neutralising
titres
at
42
compared
28.
Anti-S
anti-RBD)
geometric
mean
concentrations
(GMCs)
higher
throughout
including
(GMCs
517·8
[95%
CI
411·3–651·9]
vs
82·1
[55·2–122·3]
BAU/mL).
Also
D614G
NAb
(GMTs)
group
than
as
percentage
least
(80%
putative
risk
reduction
threshold
[PRRT]
wild-type–alpha
COVID-19),
(92·0%
[74·0–99·0]
18·2%
[2·3–51·8).
Similar
findings
observed
for
gamma.
For
BA.1,
BA.4,
GMTs
proportion
above
PRRT
substantially
28
but
no
longer
differed
between
180.InterpretationA
single
general
population,
COVID-19
coverage
low
seropositivity
90%,
could
enhance
magnitude
quality
SARS-CoV-2.FundingThe
Bill
&
Melinda
Gates
Foundation,
Medical
Research
Council,
UK
Innovation,
National
Institute
Health
Research,
Council.TranslationFor
Zulu
translation
abstract
see
Supplementary
Materials
section.
Vaccine X,
Journal Year:
2023,
Volume and Issue:
13, P. 100262 - 100262
Published: Jan. 10, 2023
Elderly
are
an
understudied,
high-risk
group
vulnerable
to
severe
COVID-19.
We
comprehensively
analyzed
the
durability
of
humoral
and
cellular
immune
responses
after
BNT162b2
vaccination
SARS-CoV-2
infection
in
elderly
younger
adults.
Vaccines,
Journal Year:
2022,
Volume and Issue:
10(2), P. 252 - 252
Published: Feb. 7, 2022
Despite
an
array
of
preventive
global
public
health
interventions,
SARS-CoV-2
has
continued
to
spread
significantly,
infecting
millions
people
across
the
globe
weekly.
Newer
variants
interest
and
concern
have
emerge,
placing
need
for
policymakers
rethink
prevention
strategies
end
pandemic.
The
approval
vaccines
use
in
December
2020
was
seen
as
a
significant
development
towards
pandemic
control
possibly
ending
However,
breakthrough
infections
be
observed
among
'fully
vaccinated',
duration
sustainability
vaccine-induced
immunity
remained
topical
discourse.
In
absence
accurate
communication,
waning
concepts
potential
further
compound
vaccine
hesitancy.
With
this
viewpoint,
we
discuss
infections,
immunity,
COVID-19
booster
shots,
inequities,
address
hesitancy
adequately
propel
vaccination
programs
forward.
Journal of Family Medicine and Primary Care,
Journal Year:
2025,
Volume and Issue:
14(2), P. 655 - 661
Published: Feb. 1, 2025
A
prospective
longitudinal
study
was
planned
to
assess
immunogenicity,
safety,
and
breakthrough
infection
rates
among
health
care
workers
(HCWs)
after
COVISHIELD™
vaccination
in
a
teaching
institute
North
India.
total
of
518
HCWs
were
enrolled
at
baseline
for
receiving
first
dose
COVISHIELD™,
429
continued
participation
second
dose,
415
followed
up
28
days
405
6
months,
403
1
year
from
February
2021
November
2022.
At
each
visit
prior,
2
ml
blood
sample
collected
plasma
separated.
Anti-SARS-Cov-2
IgG
antibodies
against
spike
protein
detected
by
Chemiluminescent
Immuno-Assay
on
the
VITROS
3600
platform
(Ortho-clinical
Diagnostics,
NJ,
USA).
Data
analysed
(completed
all
follow-ups),
using
Statistical
Package
Social
Sciences
version
21.0.
The
mean
age
participants
35.3
years
(SD
±
11.11),
males
50.2%.
(N
=
518),
proportion
reactive
25%
(95%
CI,
21-29%),
which
increased
significantly
92%
89-95%)
403),
95%
92-96%)
declined
85%
83-93%)
six
months
403).
year,
reactivity
89.3%
86-90%;
P
value
<
0.0001).
Fever
reported
31.2%
HCWs,
pain
injection
site
(27.6%),
malaise
(16.4%),
headache
(3.7%),
dizziness
(3.7%).
Immunogenicity
post-COVISHIELD™
doses
but
inclined
dose.
safety
profile
within
acceptable
limits.
Scientific Reports,
Journal Year:
2025,
Volume and Issue:
15(1)
Published: March 22, 2025
The
impact
on
immunogenicity
and
efficacy
of
SARS-CoV-2
vaccination
in
people
with
prior
COVID-19
could
differ
depending
timing
number
doses.
VATICO
study
randomized
66
hospitalized
recovered
individuals
to
receive
either
immediate
or
deferred
vaccination,
one
two
doses
mRNA
vaccines.
We
measured
binding
neutralizing
antibodies
against
at
enrollment
longitudinally.
Median
(IQR)
time
from
infection
first
was
68
(53–75)
days
the
group,
151
(137–173)
group.
At
week
48,
vaccine
did
not
influence
change
antibody
levels
relative
baseline.
Adherence
assigned
regimen
lower
particularly
participants
receiving
Although
ultimately
lacked
adequate
power
draw
firm
conclusions,
these
results
suggest
possible
benefits
prompt
after
recovery
COVID-19.
Vaccines,
Journal Year:
2022,
Volume and Issue:
10(2), P. 285 - 285
Published: Feb. 13, 2022
Several
lines
of
evidence
suggest
that
binding
SARS-CoV-2
antibodies
such
as
anti-SARS-CoV-2
RBD
IgG
(anti-RBD)
and
neutralising
(NA)
are
correlates
protection
against
SARS-CoV-2,
the
correlation
anti-RBD
NA
is
very
high.
The
effectiveness
(VE)
BNT162b2
in
preventing
infection
wanes
over
time,
this
reduction
mainly
associated
with
waning
immunity,
suggesting
kinetics
might
be
interest
to
predict
VE.
In
a
study
97
health
care
workers
(HCWs)
vaccinated
vaccine,
we
assessed
30-250
days
after
vaccination
using
388
individually
matched
plasma
samples.
Anti-RBD
levels
declined
by
85%,
92%,
95%
at
4th,
6th,
8th
month
from
peak,
respectively.
were
estimated
trajectories
various
models.
restricted
cubic
splines
model
had
better
fit
observed
data.
declines
statistically
significantly
lower
for
risk
factors
severe
COVID-19
absence
side
effects.
Moreover,
previous
was
divergent
consistent
slower
decline
time.
These
results
may
serve
harbinger
vaccine
(VE),
it
should
explored
predictor
breakthrough
infections
Exploration of Immunology,
Journal Year:
2022,
Volume and Issue:
unknown, P. 133 - 156
Published: March 16, 2022
Avidity
of
immunoglobulin
G
(IgG)
is
defined
as
its
binding
strength
to
target
antigen.
As
a
consequence
affinity
maturation
the
IgG
response,
avidity
maturing
well.
Therefore,
acute
infections
are
characterized
by
low-avidity
IgG,
whereas
past
usually
associated
with
high-avidity
IgG.
also
observed
optimal
vaccination.
has
been
shown
play
significant
role
in
protective
humoral
immunity
many
microbial
systems.
After
severe
respiratory
syndrome
coronavirus
2
(SARS-CoV-2)
infection,
situation
different
compared
other
viral
infections,
moderate
degree
reached
most
cases
infection
similar
that
after
only
one
vaccination
step.
In
contrast,
two
steps
lead
much
higher
directed
towards
spike
protein
S1
(S1)
majority
vaccinated
individuals.
it
seems
allow
for
more
extended
affinity/avidity
than
natural
infection.
The
heterogeneous.
It
can
be
further
enhanced
third
Complete
depend
on
sustained
availability
antigen
during
process.
Variants
concern
seem
increase
their
receptor-binding
domain
(RBD)
angiotensin-converting
enzyme-2
(ACE2)
and/or
decrease
susceptibility
neutralizing
antibodies.
Classical
neutralization
tests
do
not
necessarily
reflect
they
operationally
dissect
reaction
between
and
from
ACE2.
This
approach
fades
out
critical
competition
reactions
ACE
RBD
S1.
Quantitative
determination
might
an
essential
tool
define
individuals
possess
suboptimal
therefore
benefit
additional
booster
immunization.
Journal of the American Geriatrics Society,
Journal Year:
2022,
Volume and Issue:
70(9), P. 2552 - 2560
Published: April 29, 2022
Duration
of
post-vaccination
protection
against
COVID-19
in
nursing
home
(NH)
residents
is
a
critical
issue.
The
objective
this
study
was
to
estimate
the
duration
IgG(S)
response
mRNA
BNT162b2
vaccine
NH
with
(COV-Yes)
or
without
(COV-No)
history
SARS-CoV-2
infection.A
574
COV-Yes
and
COV-No
were
included
2
cohorts:
Main
(n
=
115,
median
age
87
years)
Confirmatory
459,
89
years).
quantification
carried
out
at
three
different
time
points
following
vaccine:
(1st)
seven
(2nd)
months
after
2nd
dose,
1
month
3rd
dose
(3rd
quantification)
cohort,
twice
(2nd
3rd)
cohort.
seroneutralization
capacity
according
also
measured
subgroup
patients.Neutralization
strongly
correlated
levels
(R2
:76%)
any
difference
between
groups
for
same
IgG(S).
After
assumed
robust
(IgG(S)
>264
BAU/ml)
two-fold
higher
vs.
group:
12.60
(10.69-14.44)
versus
5.76
(3.91-8.64)
months,
advantage
mainly
due
titers
secondary
slower
decay
over
time.
estimated
11.87
(9.88-14.87)
8.95
(6.85-11.04)
months.
These
results
similar
both
cohorts.In
old
subjects
living
NH,
infection
provides
clear
magnitude
high
dose.
Importantly,
induces
much
more
pronounced
than
subjects,
effect
which
should
be
able
ensure
prolonged
severe
forms
these
subjects.