Shots of Hope: COVID-19 Vaccine Reduces Long COVID in Children

Vaccination associated with moderate protection in large, diverse cohort.

Vaccination against SARS-CoV-2Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the official name of the virus strain that causes coronavirus disease (COVID-19). Previous to this name being adopted, it was commonly referred to as the 2019 novel coronavirus (2019-nCoV), the Wuhan coronavirus, or the Wuhan virus.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>SARS-CoV-2, the virusA virus is a tiny infectious agent that is not considered a living organism. It consists of genetic material, either DNA or RNA, that is surrounded by a protein coat called a capsid. Some viruses also have an outer envelope made up of lipids that surrounds the capsid. Viruses can infect a wide range of organisms, including humans, animals, plants, and even bacteria. They rely on host cells to replicate and multiply, hijacking the cell's machinery to make copies of themselves. This process can cause damage to the host cell and lead to various diseases, ranging from mild to severe. Common viral infections include the flu, colds, HIV, and COVID-19. Vaccines and antiviral medications can help prevent and treat viral infections.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>virus that causes COVID-19First identified in 2019 in Wuhan, China, COVID-19, or Coronavirus disease 2019, (which was originally called "2019 novel coronavirus" or 2019-nCoV) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has spread globally, resulting in the 2019–22 coronavirus pandemic.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>COVID-19, reduces the risk of serious acute illness in children and adolescents. However, its role in protecting against persistent health problems in the months after COVID-19, or “long COVID,” was less clear.

Now, researchers from 17 health systems in the U.S., in work led by investigators at the Children’s Hospital of Philadelphia (CHOP), have found that vaccination provides moderate protection against long COVID. Vaccination also has a stronger effect in adolescents, who have a higher risk of developing long COVID than young children.

The findings of the large retrospective study, based on electronic health records analyzed as part of the National Institutes of HealthThe National Institutes of Health (NIH) is the primary agency of the United States government responsible for biomedical and public health research. Founded in 1887, it is a part of the U.S. Department of Health and Human Services. The NIH conducts its own scientific research through its Intramural Research Program (IRP) and provides major biomedical research funding to non-NIH research facilities through its Extramural Research Program. With 27 different institutes and centers under its umbrella, the NIH covers a broad spectrum of health-related research, including specific diseases, population health, clinical research, and fundamental biological processes. Its mission is to seek fundamental knowledge about the nature and behavior of living systems and the application of that knowledge to enhance health, lengthen life, and reduce illness and disability.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>National Institutes of Health’s Researching COVID to Enhance Recovery (RECOVER) initiative, were published today (January 16) in the journal Pediatrics.

While overall severity of COVID-19 has been lower in children than adults, the burden of long COVID has been difficult to accurately describe since the symptoms can vary widely and the exact ways the virus causes them are unknown. Some symptoms include brain fog, dyspnea, gastrointestinal dysfunction, generalized pain and fatigue, while others are more acute, like inflammatory reaction or heart problems.

“To date, no studies have assessed clinical data for large, diverse groups of children to address this important question,” said lead study author Hanieh Razzaghi, PhD, MPH, Director of Analytics in the PEDSnet and RECOVER/PCORnet EHR Coordinating Centers in the Applied Clinical Research Center at Children’s Hospital of Philadelphia. “Using clinical data from across health care networks allowed us to have a large enough sample of patients to identify rare effects of the virus and its impact on children.”

The researchers analyzed results from a large-scale collaboration of health systems from PCORnet^® as part of the National Institutes of Health’s Researching COVID to Enhance Recovery (RECOVER) initiative, which was created to learn about the long-term effects of COVID-19. Data from 17 health systems were used to assess vaccine effectiveness against long COVID in two groups of patients between 5 and 11 years old and 12 and 17 years old, respectively, as well as the time period in which patients were impacted. The vaccination rate was 56% in the cohort of 1,037,936 children.

The incidence of probable long COVID was 4.5% among patients with COVID-19, though only 0.7% of patients were clinically diagnosed with long COVID. The study estimated effectiveness of the vaccine within 12 months of administration as 35.4% against probable long COVID and 41.7% against diagnosed long COVID. The estimate was higher in adolescents compared with younger children (50.3% vs. 23.8%), and higher at six months (61.4%) but decreased to 10.6% at 18 months.  Children who were vaccinated after recovering from COVID-19 also appeared to benefit, with vaccine effectiveness of 46% against probable long COVID after a subsequent episode of COVID-19.

“This study provides us with important data showing the protective effects of the vaccine against long-haul COVID and suggests that this protection is mostly from preventing visible infections.  We hope this means that as vaccines are improved to be more effective against current strains of SARS-CoV-2, their protection against long COVID will get better, too,” said senior study author Charles Bailey, MD, PhD, Associate Professor of Pediatrics and co-principal investigator for the PEDSnet and RECOVER/PCORnet EHR Coordinating Centers in the Applied Clinical Research Center at CHOP.

“These retrospective data provide guidance for additional research into the ways long COVID develops, and how we can better protect children and adolescents,” Bailey concludes.

Reference: “Vaccine Effectiveness Against Long COVID in Children ” by Hanieh Razzaghi, PhD, MPH; Christopher B. Forrest, MD, PhD; Kathryn Hirabayashi, MPH; Qiong Wu, PhD; Andrea Allen, MS; Suchitra Rao, MBBS, MSCS; Yong Chen, PhD; H. Timothy Bunnell, PhD; Elizabeth A. Chrischilles, PhD; Lindsay G. Cowell, PhD, MS; Mollie R. Cummins, PhD, RN; David A. Hanauer, MD, MS; Miranda Higginbotham, MSHA; Benjamin D. Horne, PhD, MStat, MPH; Carol R. Horowitz, MD, MPH; Ravi Jhaveri, MD; Susan Kim, MD, MMSc; Aaron Mishkin, MD; Jennifer A. Muszynski, MD, MPH; Susanna Naggie, MD; Nathan M. Pajor, MD, MS; Anuradha Paranjape, MD, MPH; Hayden T. Schwenk, MD, MPH; Marion R. Sills, MD, MPH; Yacob G. Tedla, PhD; David A. Williams, PhD; Charles Bailey, MD, PhD on behalf of the RECOVER Consortium, 16 January 2024, Pediatrics.
DOI: 10.1542/peds.2023-064446

This study was supported by the National Institutes of Health (NIH) Agreement OT2HL161847-01 as part of the Researching COVID to Enhance Recovery (RECOVER) program of research.