SciCheck Digest
Hospitals across the country are seeing a spike of respiratory syncytial virus infections among children. Experts say the spike is most likely caused by an immunity gap created by the lack of exposure to the virus over the past couple of years. Thereโs no evidence the pediatric COVID-19 vaccine is the cause, as viral posts falsely claim.
Full Story
Childrenโs hospitals across the United States are reporting full capacity due to an intense and early surge of respiratory syncytial virus infections. RSV is a common respiratory virus that usually causes mild flu-like symptoms, but can be dangerous for some people, especially older people, infants and young children.
By the end of October, the Centers for Disease Control and Prevention reported its surveillance systems were showing an increase in RSV detections and RSV-related emergency room visits and hospitalizationsin multiple areas of the country, with some regions nearing seasonal peak levels, which usually occur from later December to mid-February. Each year, 58,000 to 80,000 children under 5 are hospitalized due to RSV infection, according to the agency.
โThere are bad RSV years and less bad RSV years,โ Dr. Paul A. Offit, a vaccine expert and pediatrician at the Childrenโs Hospital of Philadelphia, told us in an interview. โThis is the worst RVS year weโve ever seen in our hospital.โ
Many experts believe the spike in RSV is primarily due to reduced immunity to the virus in the population as a result of the precautions taken during the pandemic, such as social distancing. Offit said the restrictions established in 2020 to prevent the spread of COVID-19 virtually eliminated other respiratory viruses, creating an โimmunity gap.โ
With fewer people having been recently exposed to the virus, fewer people have immunity against it and more people are susceptible to falling ill. This includes very young babies, who are at high risk of RSV and can be protected by maternal antibodies passed to them in utero, as well as slightly older children who may have never been infected. Now, with more people not wearing masks or isolating when feeling sick, RSV and other respiratory viruses are spreading more freely. Because a larger number of people will now get sick, more people will also become severely ill.
RSV, which normally infectsย nearly all children before the age of 2, isย highly contagiousย andย spreadsย when an infected person coughs or sneezes near other people, or through contaminated surfaces. People with RSV areย usually contagiousย for three to eight days, but some infants and immunocompromised people can continue to spread the virus for as long as four weeks.
Opponents of the vaccineย areย incorrectly suggestingย onlineย that the unusually high number of infections is caused by the pediatric COVID-19 vaccines.ย
An Instagram user who shared a screenshot of a tweet that linked the RSV spike to the pediatric COVID-19 vaccines wrote: โAre we surprised!? Your precious sh0ts that are saving so many lives 🙄 are causing higher rates of RSVโฆ SHOCKER I love $cience.โ
โItโs the shots, per their own trial data,โ reads anotherย Instagram post, which shares this headline of aย Substack post published on Oct. 29: โEvidence Suggests the COVID Shots Are Responsible for Soaring RSV Cases Throughout the U.S. & Canada.โ
Del Bigtree, who leads the anti-vaccine group Informed Consent Action Network, dismissed the immunity gap argument on his Nov. 1 online talk show. Instead, he incorrectly suggested the most โobviousโ explanation for the rise in RSV cases in children is the pediatric COVID-19 vaccine.
โIt shows you how desperate they are to protect the vaccine, because the vaccine should be the obvious,โ he said when presented with the immunity gap reasoning. โWhy do we suddenly have outbreaks of RSV beyond anything weโve ever seen before? Could it possibly be that injection that we know lowers the immune system and showed within 28 days an increase in RSV?โ he said.
Asย weโveย reported, there is no evidence that the COVID-19 vaccines impair immunity generally, and they increase immunity against SARS-CoV-2, the virus that causes COVID-19. This is not the first time Bigtree or his group, ICAN, hasย spread misinformationย aboutย the vaccinesย โ ICAN recently published a misleading analysis of COVID-19 vaccine safety data, asย we reported.
โThere is no evidence indicating COVID-19 vaccination can cause infection with respiratory syncytial virus (RSV),โ Kate Grusich, a CDC representative, told us in an email.
The CDC also noted that COVID-19 vaccination in the youngest children remains low โ less than 8% of children under 5 years old have received at least one dose, a coverage that โdoes not account for the surge in RSV cases seen nationally.โ
โIn addition, children under six months of age, who have always been at the highest risk of RSV-associated severe disease and hospitalization, continue to have the highest rates of RSV hospitalization among all age groups (RSV-NET Interactive Dashboard | CDC) โ and this group is not yet eligible to receive a COVID-19 vaccine,โ Grusich wrote.
No Causal Association Between RSV and COVID-19 Vaccines
Bigtreeโs speculation comes from RSV cases reported after vaccination in the pediatric mRNA COVID-19 vaccine trials. Both Moderna and Pfizer/BioNTech reported a few RSV cases in the vaccine and placebo groups 28 days after vaccination, with a slightly bigger number in the vaccine group. Both companies and the Food and Drug Administration dismissed any causal association.
Modernaย foundย that in the 6- to 23-month-old group, 0.8% of the babies that received the vaccine reported RSV, compared with 0.5% in the placebo group. In the 2- to 5-year-old cohort, 0.4% reported an RSV infection in the vaccine group and less than 0.1% in the placebo group, and in the 6- to 11-year-old cohort, 3.9% reported RSV in the vaccine group and 2.5% in the placebo group.
โAll events were assessed as not related to study vaccine by the investigators. FDA agrees with the investigator assessments that there is unlikely to be a causal association between the occurrence of these events and the study vaccine. Imbalances between mRNA-1273 and placebo groups in specific respiratory infections were not observed in older age cohorts, and there is not a clear biological mechanism that would explain a causal association for certain respiratory infections but not others,โ the FDA document reads.
โOverall, the frequency and clinical course for these events do not appear unusual given the age group of the young pediatric study population and the season (fall-winter) during which the study took place, and the observed imbalance could be due to chance. It is also possible that the observed imbalance could be due to an unappreciated bias associated with differences between treatment groups in risk avoidance for viral infections in general, health seeking behaviors, or clinical evaluation of suspected viral illnesses,โ the documentcontinues.
In the Pfizer/BioNTech trial, five participants in the 6- to 23-month-old group reported RSV bronchiolitis in the vaccine group, compared with three who reported bronchiolitis or RSV bronchiolitis in the placebo group. Both Pfizer and the FDA determined these events were not related to the vaccine.
A Pfizer media representative told us there is no possible mechanism that would explain a causal association between the spike in RSV cases and the COVID-19 pediatric vaccines.
โThe Pfizer-BioNTech COVID-19 vaccine does not contain any part of a live virus either of SARS-CoV-2 or RSV. The pediatric vaccine does not cause COVID-19 or RSV. It is also important to note that they are completely separate respiratory viruses,โ the company representative wrote in an email.
Yet, ICANโs post demanding โANSWERS FROM THE CDC ABOUT SPIKE IN RSV RATESโ continues to spread. The group sent a letter to the CDCโs director, Rochelle Walensky, asking the agency to share the percentage of children with RSV cases who had received a COVID-19 vaccine before.
ICANโs lawyer, Siri Aaron, did not reply to a request for comment.
Immunity Gap Explanation
Dr. Clarence Buddy Creech, professor of pediatrics at Vanderbilt University Medical Center and director of the Vanderbilt Vaccine Research Program, told us there is no evidence to support ICANโs suggestions.
โThereโs simply no indication that getting a COVID vaccine changes how you respond to RSV,โ he wrote in an email.
โThe differences between vaccine and placebo groupsโ were โvery small for RSV,โ he said. And he added that people should also keep in mind that viral infections are diagnosed more frequently in the clinical trials than they would be in the real world because of the intense surveillance.
Creech said he and others think the spike in RSV โis principally due to a relative lack of immunity in young children since the burden of RSV and influenza have been remarkably lower during the pandemic (likely due to masking, social distancing, school closures, and keeping children home while ill).โ
This does not mean that taking precautions during the pandemic was a bad idea, nor does it mean that people should seek out infections. The โimmunity gapโ concept, which sometimes is referred to as โimmunity debtโ or โimmune debt,โ should not be confused with the unsupported idea that reduced exposure to viruses such as RSV damages an individualโs immune system. But surges in viral infections are expected when immunity to those viruses declines in the population.
Indeed, the current spike is not a surprise to experts whoโve been watching a disruption in the circulation of seasonal viruses. A study published in Nature Communications in May showed โa major shift in the epidemiology of RSV in Australiaโ after the emergence of the virus that causes COVID-19, with โlarge scale outbreaksโ occurring out of season in 2020-2021.
โThere was no typical winter surge in hospitalisations related to RSV among children in 2020,โ a group of experts in infectious diseases from the University of Colorado School of Medicine and researchers from the ecology and evolutionary biology department at Princeton University wrote in a commentary published in the Lancet in July.
โAs NPI measures were further relaxed, interseasonal RSV outbreaks began the following spring, with waves of disease affecting older than the typical median age for childhood RSV-associated respiratory infections,โ they continued, referring to nonpharmaceutical interventions, or actions that people can take to prevent the spread of a virus, such as social distancing.
The lack of exposure to endemic viruses created an immunity gap, the researchers explained, in which there is โa group of susceptible individuals who avoided infection and therefore lack pathogen-specific immunity to protect against future infection.โ The pandemic disruptions in the health care system also resulted in fewer childhood vaccinations, they argued.
โThe cumulative effect of new susceptible birth cohorts, waning immunity over time with decreased exposures to usual endemic viruses, and lagging vaccination rates in some settings widens this immunity gap and increases the potential for future outbreaks of endemic viruses,โ they wrote.
The group warned hospitals to be prepared for โlarger outbreaks occurring out of season among older children and with atypical presentations.โ
โWe knew it was inevitable that these diseases would come back,โ Kevin Messacar, one of the researchers, told CNN, referring to RSV and other respiratory illnesses caused by endemic viruses.
There is no vaccine to prevent RSV yet, but several candidates are in development. Pfizer recently announced its RSV vaccine showed promising results and that it would seek FDA approval by the end of the year.
Editorโs note: SciCheckโs COVID-19/Vaccination Project is made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over FactCheck.orgโs editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation. The goal of the project is to increase exposure to accurate information about COVID-19 and vaccines, while decreasing the impact of misinformation.
Sources
Kekatos, Mary. โMichigan childrenโs hospital says itโs 100% full due to RSV surge.โ ABC News. 11 Nov 2022.
Portnoy, Jenna. โD.C.-area childrenโs hospitals are at capacity.โ Washington Post. 20 Oct 2022.
Betancourt, Sarah. โMass. children with RSV sent to hospitals in other states amid capacity strain.โ GBH. 24 Oct 2022.
Baumgardner, Gwen. โRSV cases soar across Washington, hospitals inundated.โ Kiro 7 News. 10 Nov 2022.
Respiratory Syncytial Virus Infection (RSV). CDC. 25 Oct 2022.
RSV National Trends. The National Respiratory and Enteric Virus Surveillance System (NREVSS). CDC. Accessed 15 Nov 2022.
RSV-NET Interactive Dashboard. CDC. Accessed 15 Nov 2022.
RSV Research & Surveillance. CDC. Updated 28 Oct 2022. Accessed 15 Nov 2022.
RSV in Infants and Young Children. CDC. Updated 28 Oct 2022. Accessed 15 Nov 2022.
Offit, Paul. Director of the Vaccine Education Center and attending physician in the Division of Infectious Diseases at Childrenโs Hospital of Philadelphia. Phone interview. 10 Nov 2022.
Oliver, Sara. COVID-19 vaccines in Children. CDC presentation for ACIP meeting. 19 Oct 2022
Shimabukuro, Tom. COVID-19 vaccine safety update: Primary series in young children and booster doses in older children and adults. CDC presentation for ACIP meeting. 1 Sep 2022.
Baumgaertner, Emily. โโThis Is Our March 2020โ: Childrenโs Hospitals Are Overwhelmed by R.S.V.โ New York Times. 3 Nov 2022.
Wu, Katherine J. โThe Worst Pediatric-Care Crisis in Decades.โ The Atlantic. 31 Oct 2022.
Nawrocki, Jeff, et al. โThe Effects of Social Distancing Policies on Non-SARS-CoV-2 Respiratory Pathogens.โ Open Forum Infectious Diseases. 17 Mar 2021.
RSV (Respiratory Syncytial Virus). Yale Medicine. Accessed 15 Nov 2022.
RSV Transmission. CDC. Updated 1 Nov 2022. Accessed 15 Nov 2022.
Romo, Vanessa. โAs Childrenโs COVID Cases Surge, Thereโs Another Virus On The Rise.โ NPR. 14 Aug 2021.
Jaramillo, Catalina. โAlready Had COVID-19? Vaccines Boost Immunity, Not โWipe Outโ Antibodies.โ FactCheck.org. Updated 25 Oct 2021.
McDonald, Jessica. โCOVID-19 Vaccination Increases Immunity, Contrary to Immune Suppression Claims.โ FactCheck.org. 30 Jul 2022.
Sparber, Sami. โTexas-based anti-vaccine group received federal bailout funds in May as pandemic raged.โ The Texas Tribune. 18 Jan 2021.
Baudoin-Laarman, Louis. โFlawed experiments exaggerate risk from CO2 concentration in masks.โ AFP Factcheck. 2 Sep 2020.
Reviews of articles by: Del Bigtree. Health Feedback.
Reuters Factcheck. โFact Check-CDC study found that over 75% of COVID-19 deaths in vaccinated people were among those with at least 4 comorbidities.โ 12 Jan 2022.
Fichera, Angelo, and Sophia Tulp. โDeceptive videos used to link athlete deaths to COVID shots.โ 17 Dec 2021.
Jaramillo, Catalina. โPosts Distort Misleading Analysis of COVID-19 Vaccine Safety Dataโ FactCheck.org. 28 Oct 2022.
COVID Data Tracker. CDC. Accessed 18 Nov 2022.
Moderna COVID-19 Vaccine EUA Amendments for Use in Individuals 6 Months Through 17 Years of Age. FDA. 16 Jun 2022.
EUA amendment request for Pfizer-BioNTech COVID-19 Vaccine for use in children 6 months through 4 years of age. FDA Briefing Document for VRBPAC meeting. 15 Jun 2022.
Increased rate of Respiratory Syncytial Virus (RSV) in Children Who Received Covid19 Vaccine. Letter from ICAN to Rochelle Walensky. 26 Oct 2022.
Creech, Clarence Buddy. Director, Vanderbilt Vaccine Research Program and professor of pediatrics. Email to FactCheck.org. 14 Nov 2022.
Elden, John-Sebastian, et al. โOff-season RSV epidemics in Australia after easing of COVID-19 restrictions.โ Nature Communications. 24 May 2022.
Messacar, Kevin, et al. โPreparing for uncertainty: endemic paediatric viral illnesses after COVID-19 pandemic disruption.โ The Lancet. 14 Jul 2022.
Christensen, Jen. โPandemic โimmunity gapโ is probably behind surge in RSV cases, scientists say.โ CNN. 28 Oct 2022.
Grusich, Kate. CDC media representative. Email to FactCheck.org. 15 Nov 2022.
Abbasi, Jennifer. โโThis Is Our COVIDโโWhat Physicians Need to Know About the Pediatric RSV Surge.โ JAMA, Medical News & Perspectives. 11 Nov 2022.
Willyard, Cassandra. โFlu and colds are back with a vengeance โ why now?โ Nature. 10 Nov 2022.
Mandavilli, Apoorva. โScientists Are Gaining on R.S.V., a Persistent Threat to Children.โ New York Times. 1 Nov 2022.
โPfizer Announces Positive Top-Line Data of Phase 3 Global Maternal Immunization Trial for its Bivalent Respiratory Syncytial Virus (RSV) Vaccine Candidate.โ Pfizer. Press release. 1 Nov 2022.




