Significant and Sustained Drop in Teen and Adult Immunization Rates During Pandemic, Study Shows

For media and investors only

Issued: Philadelphia

  • 26 million doses of CDC-recommended vaccines were missed in 2020
  • Non-influenza vaccine claims dropped up to 40% from the same period in 2019

A new claims analysis commissioned by GSK and conducted by Avalere Health, an Inovalon company, showed a sustained drop in immunization rates for recommended vaccines among teens and adults throughout the pandemic in 2020. The study examined claims for CDC-recommended vaccines across commercial, managed Medicaid, Medicare Advantage and Medicare fee-for-service Part B for January through November 2020 compared to the same time period in 2019. 

The study found:

  • Teens and adults potentially missed over 26 million doses of recommended vaccines in 2020. This includes 8.8 million missed adolescent vaccine doses and 17.2 million missed adult vaccine doses.
  • Vaccine claims remain well below 2019 levels. Total non-influenza vaccine claims submissions were between 13-35% (adolescents) and 17-40% (adults) lower than the same period in 2019.
  • Despite warnings of a potential “twindemic,” influenza immunization rates were lower in 2020 than in 2019. Early gains in influenza vaccination claims lagged as the season progressed. Influenza vaccination claims from August-September of the 2020-21 season exceeded the same months of the 2019-20 season, suggesting early heightened awareness of respiratory disease in 2020; however, those surges levelled off by October and then fell in November.

CDC recommends vaccines to protect teens against certain types of meningitis and HPV and adults against pneumonia, shingles and hepatitis A, among others.  Diphtheria, tetanus and pertussis (Tdap) vaccine and an annual influenza shot are recommended for both adolescents and adults. Even before COVID-19, immunizations were under-utilized for adults and in underserved populations[1] and the pandemic has compounded this problem. Population immunity, also referred to as herd immunity, is necessary to control spread of an infectious disease within a population, and even small drops in immunization rates can lead to a resurgence of disease as was demonstrated by the 2019 measles outbreaks.

“High immunization rates are essential for keeping diseases at bay. Teens and adults missed millions of doses of recommended vaccines during the pandemic, the cumulative impact grows like a snowball each day,” said Thomas Breuer, Chief Medical Officer, GSK Vaccines. “Millions of people have been immunized to protect against COVID but many are missing protection against other diseases. As life returns to normal, we must prioritize getting individuals caught up on their missed vaccines.”

The CDC recently issued guidance that COVID-19 vaccines and other vaccines can be administered to people on the same day. Here is the full CDC recommendation on coadministration.

“This new guidance is important and will simplify the process of getting caught up on missed vaccines for both patients and health care providers,” said Judy Stewart, GSK Senior Vice President and Head of US Vaccines. “The pandemic has been a vivid reminder of the power of vaccines to protect against disease when we put our minds and resources to it.”

Study Methodology

Avalere analyzed changes in administration of ACIP-recommended adult (≥19 years of age) and adolescent (7-18 years of age) vaccines using pre-adjudicated medical benefit Medicare fee-for-service (FFS) claims and the Inovalon MORE2 Registry®, a large scale, real-world dataset consisting of medical, pharmacy, and lab claims and clinical data on more than 336 million de-identified patients.

Specifically, Avalere compared billing for vaccine products and administration codes, defined by Current Procedural Terminology (CPT) and Healthcare Common Procedure Coding System (HCPCS) codes, from 2019 to 2020 to identify the potential impact of the COVID-19 pandemic on vaccine administration. To estimate missed doses at a national level, Avalere used a market-specific, rate-based methodology to extrapolate the number of vaccine claims to the national population.

About GSK

GSK is a science-led global healthcare company with a special purpose: to help people do more, feel better, live longer. For further information please visit

 GSK enquiries:




US Media enquiries:

Evan Berland

Sean Clements

+1 215 432 0234

+1 215 740 3088



Analyst/Investor enquiries:

James Dodwell

+44 (0) 20 8047 2406



Sonya Ghobrial

+44 (0) 7392 784784



Mick Readey

+44 (0) 7990 339653



Jeff McLaughlin

+1 215 751 7002



Frannie DeFranco

+1 215 751 4855



Cautionary statement regarding forward-looking statements

GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Such factors include, but are not limited to, those described in the Company's Annual Report on Form 20-F for 2020 and any impacts of the COVID-19 pandemic.