05 COVID Link Gelles 508

CDC ACIP — Vaccine Advisory Committee

Acip

Slides

25

Download PDF ↗ Live URL (may be dead)

Document text

Centers for Disease Control and Prevention
National Center for Immunization and Respiratory DiseasesCenters for Disease Control and Prevention
National Center for Immunization and Respiratory DiseasesCenters for Disease Control and Prevention
National Center for Immunization and Respiratory Diseases
Centers for Disease Control and Prevention 
National Center for Immunization and Respiratory Diseases 
COVID-19 vaccine effectiveness updates 
19 April 2023 
Ruth Link-Gelles, PhD, MPH 
LCDR, US Public Health Service COVID-19 Vaccine Effectiveness Program Lead Centers for Disease Control and Prevention 
Photographs and images included in this presentation are licensed solely for CDC/NCIRD online and presentation use. No rights are implied or extended for use in printing or any use by other CDC CIOs or any external audiences. 

        
         
    
          
       Organization of presentation 
 Updates on vaccine effectiveness (VE) of monovalent vaccines against 
symptomatic infection in children aged 6 months–4 years (Pfizer-BioNTech) 
and 6 months–5 years (Moderna) 
 Update on VE of monovalent and bivalent vaccines against severe disease in 
adults with and without immunocompromising conditions 
2 

     
        
    
                      
                   
     -
- - – — –
–Estimates of Effectiveness of Monovalent mRNA Vaccines in Preventing 
Symptomatic SARS-CoV-2 Infection Among Children Aged 3–5 Years, 
Increasing Community Access to Testing Program 
Updated analyses based on: Fleming Dutra KE, Ciesla AA, Roper, LE et al. Preliminary Estimates of Effectiveness of Monovalent mRNA Vaccines in Preventing 
Symptomatic SARS CoV 2 Infection Among Children Aged 3 5 Years Increasing Community Access to Testing Program, United States, July 2022 February 2023. MMWR Morb Mortal Wkly Rep 2023;72:177 182. DOI: http://dx.doi.org/10.15585/mmwr.mm7207a3 
3 
Percent of people receiving COVID-19 vaccine by age and date administered 
– United States, December 14, 2020 – April 12, 2023
https://covid.cdc.gov/covid-data-tracker/#vaccination-demog r aphics-trends 4

      
         
   
          
      
  
                   
        
                      
                       
           
                     
    Increasing Community Access to Testing (ICATT) Program: VE of monovalent 
COVID-19 vaccines against symptomatic infection in children aged 3-5 years 
 Nationwide community-based drive-through SARS-CoV-2 testing via pharmacies 
 Self-reported vaccine history at time of registration for SARS-CoV-2 testing 
 Design : Test-negative, case-control analysis* 
 Population : Immunocompetent children aged 3 – 4/5** years with ≥1 COVID-like 
sy
mptom and nucleic acid amplification testing (NAAT) 
 Period for analysis: 
• Tested: July 4, 2022*** – April 8, 2023, BA.4/BA.5 and XBB predominant period 
*Models adjusted for: age, gender, race, ethnicity, social vulnerability index and HHS region of the testing location, underlying conditions (presence versus absence), pharmacy 
chain conducting the test, local incidence (cases per 100,000 by individual county and state in the 7 days before test date), and date of testing. ** ICATT testing is generally limited to children ages 3 and up. ***Analysis start date depended on vaccine/dose number being analyzed: Pfizer and Moderna 1
st doses started 7/4/2022; Pfizer 2nd dose started 7/25/2022; Moderna 2nd dose 
started 8/1/2022; Pfizer 3rd dose started 9/19/2022. 5 

ICATT: Estimates of VE for primary series monovalent Moderna vaccine (children aged 
3–5 yea
rs) against symptomatic infection , July 4, 2022 – April 8, 2023
6Updated from: Fleming-Dutra, Ciesla, Roper, et al. MMWR February 16, 2023.
*Test registrants who report receiving COVID-19 vaccines are asked to report the total number of doses and manufacturer(s) of vaccines received 
and for the most recent dose, month and year of receipt; therefore, the number of months between a vaccine dose and testing is a whole number calculated as the difference between the month and year of testing and the month and year of the vaccine dose. For doses received in the same month or the month before SARS-CoV-2 testing, an additional question was asked to specify whether the dose was received ≥2 weeks before testing, and only doses received ≥2 weeks before testing were included. 17% and 21% of children who received 1 and 2 doses of Moderna, respectively, reported a prior infection >90 days before the current test.Vaccination status (months since last dose) Total testsSARS-CoV-2
positive, N (%)Adjusted
VE (95% CI)
Moderna, 1 dose (partial series; ages 3-5 years)
July 4, 2022 – April 8, 2023
Unvaccinated 36,779 9,801 (27) Ref
1monovalent dose (2 weeks–1 month)* 515 107 (21) 40 (25 to 52)
Moderna, 2 doses (complete series; ages 3-5 years)
August 1, 2022 – April 8, 2023
Unvaccinated 26,856 5,972 (22) Ref
2 monovalent doses (2 weeks–6 months)* 1,613 183 (11) 47 (37 to 54)
2 monovalent doses (2 weeks–1 month)* 461 48 (10) 61 (47 to 71)
2 monovalent doses (2–3 months)* 647 63 (10) 54 (41 to 65)
2monovalent doses (4–6 months)* 505 72 (14) 18 (-6 to 37)
20 0 20 40 60 80 100
VaccineEffectiveness (%)-
ICATT: Estimates of VE for primary series monovalent Pfizer-BioNTech vaccine (children 
aged 3–4 years) against symptomatic infection , July 4, 2022 – April 8, 2023
7Upd
ated from: Fleming-Dutra, Ciesla, Roper, et al. MMWR February 16, 2023.
*Test registrants who report receiving COVID-19 vaccines are asked to report the total number of doses and manufacturer(s) of vaccines received 
and for the most recent dose, month and year of receipt; therefore, the number of months between a vaccine dose and testing is a whole number calculated as the difference between the month and year of testing and the month and year of the vaccine dose. For doses received in the same month or the month before SARS-CoV-2 testing, an additional question was asked to specify whether the dose was received ≥2 weeks before testing, and only doses received ≥2 weeks before testing were included. 18%, 19% and 21% of children who received 1, 2, and 3 doses of Pfizer, respectively, reported a prior infection >90 days before the current test.
**There was insufficient power to stratify Pfizer-BioNTech 3-dose VE estimates by time since vaccination.Vaccination status (months since last dose)Total 
testsSARS-CoV-2
positive, N (%)Adjusted
VE (95% CI)
Pfizer, 1 dose (partial series; ages 3–4 years)
July 4, 2022–April 8, 2023
Unvaccinated 23,376 6,381 (27) Ref
1 monovalent dose (2 weeks–1 month)* 448 114 (25) 20 (0 to 36)
Pfizer, 2 doses (partial series; ages 3–4 years)
July 25, 2022–April 8, 2023
Unvaccinated 18,492 4,469 (24) Ref
2 monovalent doses (2 weeks–3 months)* 951 140 (15) 40 (28 to 50)
Pfizer, 3 doses (complete series; ages 3–4 years)**
September 19, 2022–April 8, 2023
Unvaccinated 8,610 1,445 (17) Ref
3 monovalent doses (2 weeks–6 months)* 478 64 (13) 27 (4 to 45)
0 0 20 40 60 80 100
VaccineEffectiveness (%)-2
                
    
              
         
              
    
              
          
        
            Limitations 
 Vaccine coverage is low in children aged ≤5 years. VE estimates may be less stable when 
vaccine coverage is low. 
 Prevalence of prior infection in children is high*; consequently, VE in this analysis reflects the current situation among young children in the United States. 
 Low vaccination coverage in this age group may impact future ability to estimate VE, 
including against more severe outcomes. 
 The goal of the U.S. COVID-19 vaccination program is to prevent severe disease; however, VE against symptomatic infection provides important insight into vaccine protection, 
especially before VE estimates for key questions are available. 
*https://covid.cdc.gov/covid-data-tracker/#pediatric-seroprevalence ; 92% seroprevalence in children 6 months -17 years nationally by December 2022. 8 

        
           
    
           
   
             
        
         
              
        
              
   Conclusions 
 Complete monovalent primary series vaccination helped provide protection for 
children aged 3–5 years against symptomatic SARS-CoV-2 infection for at least the 
first 3 months after vaccination. 
 Waning of monovalent Moderna primary series appears to occur by 4–6 months 
after the second dose. 
 Initial protection and waning patterns are similar to those observed in older children 
and adults in the first months after vaccination. 
 Waning of monovalent Pfizer-BioNTech VE against symptomatic infection could not 
be assessed but is also likely based on analyses in older children and adults. 
 Children should stay up to date with COVID-19 vaccines. 
 CDC will continue to monitor VE in this age group, including against severe disease and for bivalent doses. 
9 

     
    
      
  
                     
                
       - –
— –
–Updated estimates of bivalent VE against 
emergency department/urgent care encounters 
and hospitalizations among adults aged ≥18 years, VISION Network 
Updated analyses based on: Tenforde MW, Weber ZA, Natarajan K, et al. Early Estimates of Bivalent mRNA Vaccine Effectiveness in Preventing COVID 19 
Associated Emergency Department or Urgent Care Encounters and Hospitalizations Among Immunocompetent Adults VISION Network, Nine States, September November 2022. MMWR Morb Mortal Wkly Rep 2023;71:1637 1646. DOI: http://dx.doi.org/10.15585/mmwr.mm7153a1 
      
    
     
   
 
      
   
     
 
   
     
       
      
       
  
      
 Cases :COVID-like illness (CLI) with 
positive PCR for SARS-CoV-2 within 14 
days before or 72 hours after the admission or encounter 

 Controls : CLI with negative PCR for SARS-
CoV-2 VISION Multi-State Network of Electronic Health Records 
 Variant periods designated for 
analysis based on time when novel sublineage became predominant at study site 

 VE adjusted for age, sex, race, ethnicity, geographic region, calendar time, and local rates of SARS-CoV-2 circulation 

 Vaccination documented by electronic health records and state and city registries 
11 

VISION: Absolute VE of monovalent and bivalent booster against ED/U C 
encounters among immunocompetent adults aged ≥18 years, by age group –
September 2022 – March 2023*
*Unpublished CDC data.  1
2SARS-CoV-2- Median interval
mRNA Dosage PatternTotal
teststest-positive,
N (%)since last dose,
days (IQR)Adjusted VE
(95% CI)
Aged 18-64 years
Unvaccinated (ref) 55,418 5,699 (10) -- Ref
Monovalent doses only, last dose ≥2 months earlier 81,766 8,518 (10) 391 (311-518) 4 (0-7)
Bivalent booster, 7-59 days earlier 6,744 399 (6) 33 (20-46) 53 (48-58)
Bivalent booster, 60-119 days earlier 5,834 428 (7) 84 (71-100) 42 (35-47)
Bivalent booster, 120-179 days earlier 2,352 243 (10) 139 (129-153) 15 (2-26)
Aged ≥65 years
Unvaccinated (ref) 10,559 1,833 (17) -- Ref
Monovalent doses only, last dose ≥2 months earlier 42,019 5,721 (14) 343 (215-441) 20 (15-25)
Bivalent booster, 7-59 days earlier 9,103 724 (8) 35 (21-47) 61 (57-64)
Bivalent booster, 60-119 days earlier 9,086 935 (10) 86 (73-101) 47 (42-52)
Bivalent booster, 120-179 days earlier 3,857 483 (13) 139 (129-153) 25 (16-34)
0 20 40 60 80 100Vaccine Effectiveness (%)
VISION: Absolute VE of monovalent and bivalent booster against 
hospit
alization among immunocompetent adults aged ≥18 years, by age 
group – September 2022 – March 2023*
*Unpublished CDC data.  **Not included due to imprecise estimates (confidence intervals >50 percentage points). 13SARS-CoV-2- Median interval
mRNA Dosage PatternTotal
teststest-positive,
N (%)since last dose,
days (IQR)Adjusted VE
(95% CI)
Aged 18-64 years
Unvaccinated (ref) 7,126 565 (8) -- Ref
Monovalent doses only, last dose ≥2 months earlier 9,621 659(7) 388 (300-522) 21 (10-30)
Bivalent booster, 7-59 days earlier 839 28 (3) 33 (21-46) 68 (53 to 79)
Bivalent booster, 60-119 days earlier 746 56 (8) 84 (70-101) 27 (2 to 46)
Bivalent booster, 120-179 days earlier 268 21 (8) 137 (128-150) **
Aged ≥65 years
Unvaccinated (ref) 6,687 1,132 (17) -- Ref
Monovalent doses only, last dose ≥2 months earlier 20,474 2,735 (13) 354 (232-460) 25 (18 to 31)
Bivalent booster, 7-59 days earlier 35 (21-47) 64 (59 to 69) 3,494 264 (8)
Bivalent booster, 60-119 days earlier 3,561 358 (10) 86 (73-102) 53 (46 to 59)
Bivalent booster, 120-179 days earlier 1,472 158 (11) 139 (128-152) 39 (26 to 50)
0 20 40 60 80 100
Vaccine Effectiveness (%)
VISION: Absolute VE of bivalent booster against hosp italization among 
immunocompromised adults aged ≥18 years –
September 2022 – March 2023*
*Unpublished CDC data. 1
4Median SARS-CoV-2-
mRNA Dosage PatternTotal 
teststest-positive,
N (%)interval
since last dose,
days (IQR)Adjusted VE
(95% CI)
Unvaccinated (ref) 2,763 295 (11) -- Ref
Monovalent doses only, last dose ≥2 months earlier 9,232 977 (11) 343 (225-452) 5 (-10 to 18)
Bivalent booster, 7-59 days earlier 1,518 134 (9) 33 (19-46) 30 (12 to 44)
Bivalent booster, 60-119 days earlier 1,610 125 (8) 87 (73-102) 43 (28 to 55)
Bivalent booster, 120-179 days earlier 723 59 (8) 139 (129-152) 31 (4 to 50)
-20 0 20 40 60 80 100
Vaccine Effectiveness (%)
     
       
  
     
       
          
       
    
    
      
         
         
         
         
      
        
                  
               
          Characteristics of patients with COVID-19-associated hospitalizations, — VISION 
Network, 10 States, October 29, 2022–March 29, 2023 
All hospitalizations Critical hospitalizations* 
Characteristic N=9499 N=1839 
Age, median (IQR), years 75 (65–84) 74 (63–83) 
Female sex, No. (%) 4818 (50.7) 881 (47.9) 
No. of categories of underlying medical conditions, median (IQR)** 3 (2–4) 4 (3–5) 
Immunocompromising condition, No. (%) 1677 (17.7) 438 (23.8) 
COVID-19 vaccination status, No. (%) 
Unvaccinated 2842 (29.9) 625 (34.0) 
Complete primary series 2273 (23.9) 451 (24.5) 
Primary series + 1 booster dose 2388 (25.1) 445 (24.2) 
Primary series + 2 booster doses 1320 (13.9) 218 (11.9) 
Primary series + 3 booster doses 668 (7.0) 97 (5.3) 
Primary series + 4 booster doses 8 (0.1) 3 (0.2) 
Received mRNA bivalent dose*** 1567 (16.5) 269 (14.6) 
*Admitted to an intensive care unit and/or in-hospital death. 
**Categories of underlying medical conditions include pulmonary, cardiovascular, cerebrovascular, neurological or musculoskeletal, endocrine or metabolic, hematologic, renal, hepatic, and immune. 
***Any mRNA vaccine doses received on or after September 2, 2022 were considered to be bivalent. 
Note: this analysis includes recipients of mRNA or Janssen primary series 

    
     
 
                     
                  
  - –
— –
–Updated estimates of bivalent VE against 
hospitalizations among adults aged ≥65 years, 
IVY Network 
Updated analyses based on: Surie D, DeCuir J, Zhu Y, et al. Early Estimates of Bivalent mRNA Vaccine Effectiveness in Preventing COVID 19 Associated 
Hospitalization Among Immunocompetent Adults Aged ≥65 Years IVY Network, 18 States, September 8 November 30, 2022. MMWR Morb Mortal Wkly Rep 2022;71:1625 1630. DOI: http://dx.doi.org/10.15585/mmwr.mm715152e2 

      
 
     
   
   
       
        
       
       
     
     
                          IVY Network — 25 hospitals, 20 U.S. States 
 Design : Prospective, case-control 
 Period : September 8, 2022–April 1, 2023 
 Population : Adults aged ≥18 years hospitalized 
w
ith COVID-like illness (CLI)* 

 Cases: CLI and test positive for SARS-CoV-2 by RT
-
P
CR or antigen test within 10 days of illness 

 Controls: CLI and test negative for SARS-CoV-2 and 
influenza by RT-PCR within 10 days of illness 

 VE adjustments: Age, sex, race and ethnicity, 
admission date (biweekly), and HHS region 
*COVID-like illness (CLI) is defined as presence of any one of the following: fever, cough, shortness of breath, chest imaging consistent with pneumonia, new or worsening hypoxemia 17 

Absolute and relative VE against COVID-19 hospitalizations
among immunocompetent adults aged ≥65 years — IVY 
Network, September 8, 2022 – April 1, 2023
18Vaccinated Median time
Vaccinated cases, controls, since last dose, Adjusted VE,
no./total no. (%) no./total no. (%) days (IQR) % (95% CI)
Absolute VE
Unvaccinated (Ref) --
Monovalent doses only, last dose ≥2 months earlier 783/997 (79) 884/1101 (80) 373 (259–476) 13 (-9 to 30)
Bivalent booster dose, 7–59 days earlier 61/275 (22) 175/392 (45) 34 (19–49) 65 (49–77)
Bivalent booster dose, 60–119 days earlier 105/319 (33) 183/400 (46) 89 (73–103) 43 (17–60) 
Bivalent booster dose, 120–179 days earlier 73/287 (25) 92/309 (30) 141 (129–154) 22 (-26 to 52)
Relative VE
Monovalent doses only, last dose ≥2 months earlier (Ref)
Bivalent booster dose, 7–59 days earlier 61/844 (7) 175/1059 (17) 34 (19–49) 60 (45–71) 
Bivalent booster dose, 60–119 days earlier 105/888 (12) 183/1067 (17) 89 (73–103) 35 (14–51) 
Bivalent booster dose, 120–179 days earlier 73/856 (9) 92/976 (9) 141 (129–154) 17 (-21 to 42)
-40 -20 0 20 40 60 80 100
Vaccine Effectiveness (%)
     
      
    
Estimates of monovalent VE against invasive 
mechanical ventilation and death among adults 
aged ≥18 years, IVY Network  
IVY: Effectiveness of 2-4 monovalent mRNA COVID-19 vaccine doses against 
COVI
D-19 invasive mechanical ventilation or death among 
immunocompetent adults aged ≥18 years — IVY Network, February 1, 2022 –
January 31, 2023
20Median time
Vaccinated since last Absolute 
Vaccinated cases,
no./total no. (%)controls, 
no./total no. (%)dose,
days (IQR)adjusted VE,
% (95% CI)
Overall 216/362 (60) 3080/4059 (76) 248 (138–378) 62 (52–70)
Age group, yrs --
18–64 85/163 (52) 1421/2095 (68) 263 (144–380) 57 (39–70)
≥65 131/199 (66) 1659/1964 (84) 238 (133–375) 69 (57–78)
Time since last dose to illness, days
7–179 63/209 (30) 1112/2091 (53) 109 (68–145) 76 (66–83)
180–364 95/241 (39) 1110/2089 (53) 269 (220–317) 54 (37–66)
≥365 58/204 (28) 858/1837 (47) 455 (402–549) 56 (36–69)
-20 0 20 40 60 80 100
Vaccine Effectiveness (%)
Effectiveness of monovalent mRNA COVID-19 vaccines against COVID-19 
invasive mechanical ventilation or death among immunocompetent adults 
aged ≥18 years — IVY Network, February 1, 2022 – January 31, 2023
2
1Median time
Vaccinated since last Absolute 
Vaccinated cases,
no./total no. (%)controls, 
no./total no. (%)dose,
days (IQR)adjusted VE,
% (95% CI)
Time since last dose to illness, by no. of doses 
received
7–179 days before illness
2 doses 6/152 (4) 108/1087 (10) 114 (72–153) –*
3 doses 42/188 (22) 633/1612 (39) 116 (75–147) 70 (55–81)
§4 doses 15/91 (17) 353/860 (41) 94 (55–135) 84 (69–92)
≥180 days before illness
2 doses 81/227 (36) 953/1932 (49) 418 (326–531) 50 (32–64)
3 doses 66/212 (31) 901/1880 (48) 292 (235–366) 59 (42–72)
§4 doses 4/80 (5) 108/615 (18) 223 (197–258) –*
*VE estimate not reported because of insufficient sample size
§Logistic regression models for VE of 4 monovalent doses were restricted to patients aged ≥50 years admitted during April 5, 2022–January 31, 20230 20 40 60 80 100
Vaccine Effectiveness (%)
         
           
 
           
  
              
     
       
         Limitations of VE against severe disease 
 For estimates of absolute vaccine effectiveness, if unvaccinated are meaningfully 
different from vaccinated individuals (e.g., by COVID-19 risk factors), estimates may 
be biased. 
 For estimates of relative vaccine effectiveness, residual protection from prior doses is 
an important consideration. 
 Information on prior infection is limited, although we know rates of prior infection in the U.S. population are high. 
 VE against COVID-19-associated hospitalization may underestimate protection against more severe COVID-19 disease. 
22 

        
        
           
             
       
          
  
             
           
            
            Conclusions: updates to VE of bivalent COVID-19 boosters 
 Bivalent boosters are helping provide additional protection against emergency 
department/urgent care encounters and hospitalization, though evidence of 
waning 
 For most people who received monovalent doses and are eligible for a bivalent 
booster, more than a year has elapsed since their last monovalent dose. Because of waning, they may have limited remaining protection. 
 Vaccines provide durable protection against the most critical illness (mechanical ventilation and death) 
 CDC will continue ongoing monitoring of VE, including for all outcomes of interest and for all authorized vaccines in the U.S. (Pfizer-BioNTech, Moderna, Janssen, Novavax) with a focus on assessing new policy recommendations and VE in 
populations at higher risk of severe COVID-19 
23 

     
 
 
 
 
 
 
 
 
 
 
 
 
 
    
 
 
 
 
 
 
   
 
 Acknowledgements 
CDC COVID-19 Vaccine Effectiveness and 
Policy Team 
 Amadea Britton 
 Allison Ciesla 
 Monica Godfrey 
 Eric Griggs 
 Katherine Fleming-Dutra 
 Morgan Najdowski 
 Sara Oliver 
 Amanda Payne 
 Lauren Roper 
 Laura Steinhardt 
 Evelyn Twentyman 
 Megan Wallace 
 Ryan Wiegand VE platforms teams, including: 
 Sarah Ball 
 Jennifer DeCuir 
 Monica Dickerson 
 Margaret Dunne 
 Matthew Levy 
 Patrick Mitchell 
 Palak Patel 
 Caitlin Ray 
An
d many more!!!  Sarah Reese 
 Zach Smith 
 Diya Surie 
 Zack Weber 
 Mark Tenforde 
24 

    
 
      
                           
                          
         For more information, contact CDC 
1-800-CDC-INFO (232-4636) TTY: 1-888-232-6348 www.cdc.gov 
The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. 
Photographs and images included in this presentation are licensed solely for CDC/NCIRD online and presentation use. No rights are implied or extended for use in printing or 
any use by other CDC CIOs or any external audiences.