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Vaccines are a necessary protective measure in the fight against COVID-19. The CDC recommends practicing A/I specialists have conversations with patients about the importance of getting vaccinated. Take advantage of these resources to learn about vaccination options and stay informed on relevant data.

If you do not have insurance to pay for COVID-19 vaccines you can find COVID 19 vaccine locations near you:

Current CDC Recommendations

This analysis of data from the CDC’s VISION VE network showed that the monovalent XBB.1.5 vaccine was 38% effective against hospitalization in the 7-59 days after receipt in the immunocompromised adult population, and 34% in the 60-119 days after receipt. Only 18% of the individuals in this high-risk population received the updated COVID-19 vaccine. Immunocompromising conditions included solid organ malignancy in 36% and other intrinsic immune conditions or immunodeficiency in 38%. Interim Effectiveness of Updated 2023–2024 (Monovalent XBB.1.5) COVID-19 Vaccines Against COVID-19–Associated Hospitalization Among Adults Aged ≥18 Years with Immunocompromising Conditions — VISION Network, September 2023–February 2024 | MMWR ( - March 28, 2024

In early 2023 the CDC and the FDA noted a safety concern for ischemic stroke among adults 65 years of age and older who received an mRNA vaccine. It turns out that the culprit was simultaneous administration of the high-dose flu vaccine with the mRNA vaccine. An increased risk was also found for high-dose influenza vaccine by itself. Stroke Risk After COVID-19 Bivalent Vaccination Among US Older Adults | Coronavirus (COVID-19) | JAMA | JAMA Network - March 19, 2024

Multisystem inflammatory Syndrome (MIS-C) incidence has decreased from early in the pandemic but continues to occur. Among 117 patients with this condition reported to the CDC in 2023, more than 80% were vaccine eligible but unvaccinated. Among the 20 vaccinated children 60% likely had waned immunity at the time of their illness. Notes from the Field: Surveillance for Multisystem Inflammatory Syndrome in Children — United States, 2023 | MMWR ( - March 14, 2024

The updated COVID-19 vaccine (monovalent XBB.1.5) was 51% effective against ED, Urgent Care visits in adults in the first 7-59 days and 39% effective in the 60-119 days after an updated dose compared to compared to those who had not received the updated vaccine. Interim Effectiveness of Updated 2023–2024 (Monovalent XBB.1.5) COVID-19 Vaccines Against COVID-19–Associated Emergency Department and Urgent Care Encounters and Hospitalization Among Immunocompetent Adults Aged ≥18 Years — VISION and IVY Networks, September 2023–January 2024 | MMWR ( – February 29, 2024

As of December 9, 2023, only 18.3% of eligible adults had received the latest COVID-19 vaccine. Influenza, Updated COVID-19, and Respiratory Syncytial Virus Vaccination Coverage Among Adults — United States, Fall 2023 | MMWR ( - December 22, 2023

As of December 9, 2023, only 18.3% of eligible adults had received the latest COVID-19 vaccine. Influenza, Updated COVID-19, and Respiratory Syncytial Virus Vaccination Coverage Among Adults — United States, Fall 2023 | MMWR ( - December 22, 2023

This study from the VISION network of the CDC (6 sites in 8 states, EHR network) evaluated vaccine effectiveness against Urgent Care or ED visits in children from 6 months – 4 or 5 years after the primary series and with primary series plus bivalent booster, compared to unvaccinated children. VE after a Moderna primary series was 29% 14 or more days (median 100 days) after completion for Moderna, and 43% for Pfizer after a median of 75 days. For children who had received one or more bivalent boosters after their primary series, irrespective of manufacturer, VE was 80% after a median of 58 days. Effectiveness of Monovalent and Bivalent mRNA Vaccines in Preventing COVID-19–Associated Emergency Department and Urgent Care Encounters Among Children Aged 6 Months–5 Years — VISION Network, United States, July 2022–June 2023 | MMWR ( - August 18, 2023

Efficacy Information

Vaccine efficacy has most often been measured by the rate of infection at various time points after vaccination. SARS-CoV-2 antibody levels have been measured in a number of studies, but it isn’t clear what levels are protective. This study done in NBA players and staff (mostly young and male) evaluated the relationship between antibody levels measured at a single point in time and protection from infection in vaccinated individuals in the fall of 2021. Results were adjusted for age, time since last vaccine dose and history of infection. The adjusted hazard ratio for infection within 90 days of serological testing was 2.4 (95% CI 1.5-3.7) for antibody levels <250 AU/ml and 1.5 (95% CI 0.98-2.4) for levels between 250 and 800, compared to those with levels > 800 AU/ml. Low antibody levels associated with significantly increased rate of SARS‐CoV‐2 infection in a highly vaccinated population from the US National Basketball Association - Tai - 2024 - Journal of Medical Virology - Wiley Online Library – March 11, 2024

A study from Denmark on a cohort of all individuals aged 65 and older (over 1 million people) who received a dose of the monovalent XBB.1.5 mRNA vaccine demonstrated that there was no increased risk of adverse events compared to earlier vaccines. Adverse Events After XBB.1.5-Containing COVID-19 mRNA Vaccines | Vaccination | JAMA | JAMA Network – February 26, 2024

Fall of 2023 was marked by circulation of XBB variants, but by December JN.1, from the Omicron BA.2.86 lineage, became prominent. This study of VE against symptomatic infection found that those who had received the updated SARS-CoV-2 vaccine (XBB monovalent) had 60% protection against XBB variants, and 49% against presumed JN.1 (identified by S-gene target failure on PCR) 60-119 days after vaccination. Early Estimates of Updated 2023–2024 (Monovalent XBB.1.5) COVID-19 Vaccine Effectiveness Against Symptomatic SARS-CoV-2 Infection Attributable to Co-Circulating Omicron Variants Among Immunocompetent Adults — Increasing Community Access to Testing Program, United States, September 2023–January 2024 | MMWR ( - February 1, 2024

In addition to preventing hospitalization and death, this study from the CDC also shows that vaccination with bivalent mRNA vaccines also prevents thromboembolic events in those over 65, compared with the receipt of the original monovalent vaccines alone. Effectiveness of Bivalent mRNA COVID-19 Vaccines in Preventing COVID-19–Related Thromboembolic Events Among Medicare Enrollees Aged ≥65 Years and Those with End Stage Renal Disease — United States, September 2022–March 2023 | MMWR ( – January 11, 2024

In this national survey, participants equally felt that COVID-19 and Influenza vaccines were effective, but diverged on safety with more feeling that influenza vaccine was safer. The more vaccine-hesitant among those surveyed were even more concerned about the safety and efficacy of the COVID-19 vaccine, and more distrustful of agencies promoting vaccination. Divergent Attitudes Toward COVID-19 Vaccine vs Influenza Vaccine | Public Health | JAMA Network Open | JAMA Network - December 21, 2023

This study shows that vaccination in previously infected individuals leads to a large expansion and increased diversity of T cell clones. Repeated mRNA vaccination sequentially boosts SARS-CoV-2-specific CD8+ T cells in persons with previous COVID-19 | Nature Immunology - December 6, 2023

Efficacy in children between 6 months and 5 years. Compared to unvaccinated children adjusted OR for ED or Urgent Care encounter 0.70, 0.60 for outpatient visits and 0.67 for either outcome. Receipt of BNT162b2 Vaccine and COVID-19 Ambulatory Visits in US Children Younger Than 5 Years | Vaccination | JAMA | JAMA Network - September 15, 2023

Vaccine Safety and Efficacy in Adolescents                                                                                               
Despite the earlier approval for the mRNA vaccines in adolescents, only a minority have received the vaccine. This update from the ongoing phase 2-3 placebo-controlled trial of the mRNA-1273 (Moderna) shows that local reactions (primarily injection site pain, swelling and erythema) occurred in 93.1% and 92.4% after the first and second dose respectively. 95% of these reactions were mild to moderate. Systemic reactions (headache, fatigue, chills were the most common) occurred in 68.5% and 86.1% respectively, with 85% being mild to moderate. Efficacy was similar to that in young adults. You can use this information to help convince your adolescent patients and their parents to consent to the vaccine. In another study, cardiologists report that in a small study of adolescents with myocarditis following the mRNA vaccine most tended to have a mild course, similar to young adults. 

CDC: How to Talk with Parents about COVID-19 Vaccination 

Vaccine Data and Approvals

Booster Doses

FDA Takes Action on Updated mRNA COVID-19 Vaccines to Better Protect Against Currently Circulating Variants - September 11, 2023

Among adults aged ≥18 years without immunocompromising conditions, bivalent booster vaccine effectiveness (VE) against COVID-19–associated hospitalization declined from 62% at 7–59 days postvaccination to 24% at 120–179 days compared with VE among unvaccinated adults. Among immunocompromised adults, lower bivalent booster VE was observed. However, bivalent booster VE was sustained at 50% against critical COVID-19–associated outcomes, including intensive care unit admission or death. Estimates of Bivalent mRNA Vaccine Durability in Preventing COVID-19–Associated Hospitalization and Critical Illness Among Adults with and Without Immunocompromising Conditions — VISION Network, September 2022–April 2023 | MMWR (

Janssen COVID-19 Vaccine
On June 1, the FDA revoked the emergency use authorization (EUA) of the Janssen COVID-19 Vaccine. On May 22, Janssen Biotech Inc. requested the voluntary withdrawal of the EUA for this vaccine. Janssen Biotech, Inc. informed the FDA that the last lots of the vaccine purchased by the U.S. Government have expired, there is no demand for new lots of the vaccine in the U.S., and they do not intend to update the strain composition of this vaccine to address emerging variants.

Novavax (NVX-CoV2373) is a subunit vaccine made from a stabilized form of the spike protein using recombinant protein nanoparticle technology combined with a proprietary adjuvant. The vaccine is administered as two doses, 21 days apart.  Novavax COVID-19 Vaccine, Adjuvanted (2023-2024 Formula) is authorized for use as an initial series or as booster doses in individuals 12 years of age and older. It can be considered as an alternative to those who are concerned about mRNA technology, since it is based on prior technology, or in those who had moderate to severe reactions to mRNA vaccines.

Additional Vaccine Information

NIH-sponsored trial of nasal COVID-19 vaccine opens. The study aims to enroll 60 adult participants, ages 18 to 64 years old, who previously received at least three prior doses of an FDA-approved or -authorized mRNA COVID-19 vaccine. The trial sites are Baylor College of Medicine, Houston; The Hope Clinic of Emory University, Decatur, Georgia; and New York University, Long Island. Hana M. El Sahly, M.D., at the Baylor College of Medicine Vaccine Research Center, is leading the study. NIH-sponsored trial of nasal COVID-19 vaccine opens | National Institutes of Health (NIH) – July 1, 2024

Over 90% of patients with immediate hypersensitivity reactions, including anaphylaxis, after SARS-CoV-2 vaccination can be revaccinated without further reactions based on the Canadian experience. Revaccination outcomes among adolescents and adults with suspected hypersensitivity reactions following COVID-19 vaccination: A Canadian immunization research network study - PubMed ( – June 22, 204

Using a mouse model, these investigators found that IL-1β drives the cognitive impairment that occurs after infection with SARS-CoV-2, and that this impairment can be prevented by vaccination, even in cases of breakthrough infection. Vaccination prevents cognitive impairment after breakthrough infection with SARS-CoV-2 | Nature Immunology and Vaccination reduces central nervous system IL-1β and memory deficits after COVID-19 in mice | Nature Immunology – June 20, 2024

Early vaccine side effects (chills, tiredness, etc.) really are associated with higher neutralizing antibody titers. COVID-19 Vaccine Side Effects and Long-Term Neutralizing Antibody Response: A Prospective Cohort Study: Annals of Internal Medicine: Vol 0, No 0 ( – June 11, 2024

Are preschool-aged children at risk of seizures after mRNA vaccines? In this cohort study of pediatric enrollees across 3 commercial health insurance databases, statistical signals detected for myocarditis or pericarditis after BNT162b2 (ages 12-17 years) were consistent with previous reports, and seizures after BNT162b2 (ages 2-4 years) and mRNA-1273 vaccinations (ages 2-5 years) should be further investigated in a robust epidemiologic study with confounding adjustment. Safety of Ancestral Monovalent BNT162b2, mRNA-1273, and NVX-CoV2373 COVID-19 Vaccines in US Children Aged 6 Months to 17 Years | Pediatrics | JAMA Network Open | JAMA Network - April 24, 2024

There was, and there remains, some argument about whether young children should routinely be immunized against SARS-CoV-2, since serious infections are very uncommon in this age group. In this case series including 3.9 million children in the state of California, pediatric vaccination was estimated to avert 146 210 cases of COVID-19 among adolescents aged 12 to 15 years during a 141-day postvaccine evaluation period and 230 134 cases among children aged 5 to 11 years during a 199-day postvaccine evaluation period. In addition, an estimated 168 hospitalizations were averted among children aged 6 to 59 months during a 225-day evaluation period. COVID-19 Vaccination and Incidence of Pediatric SARS-CoV-2 Infection and Hospitalization | Pediatrics | JAMA Network Open | JAMA Network - April 23, 2024

I am sure all of us continue to encounter patients who express safety concerns as a reason to avoid vaccination. This paper reviews how the multiple, complementary monitoring systems worked to rapidly detect, assess, and verify a vaccine safety signal. Overview of U.S. COVID-19 vaccine safety surveillance systems - PubMed ( - April 23, 2024

A systematic review of the effect of vaccination, before and after infection and in patients with Long -COVID determined that COVID-19 vaccines might have protective and therapeutic effects on Long COVID, but more studies are needed. Effect of covid-19 vaccination on long covid: systematic review | BMJ Medicine

Can intramuscularly administered messenger RNA vaccines induce mucosal immunity? In this cohort study of 427 vaccinated individuals, a modest increase in spike-specific IgA levels in saliva of SARS-CoV-2–naive individuals having received the Moderna or Pfizer-BioNTech messenger RNA vaccines was observed using ultrasensitive digital enzyme-linked immunosorbent assay. This increase persisted after Moderna vaccination, and previously infected individuals demonstrated a stronger mucosal IgA response to vaccination. Serum and Salivary IgG and IgA Response After COVID-19 Messenger RNA Vaccination | Vaccination | JAMA Network Open | JAMA Network - April 23, 2024

Previous studies have shown that earlier doses of mRNA vaccines were associated with an increased risk for myocarditis/pericarditis in adolescent and young adult males. That complication appears to have declined following booster doses. Nonetheless, some people have suggested that vaccination is associated with a large number of cardiac deaths in young athletes. To assess this possibility, investigators searched death certificates for Oregon residents aged 16–30 years who died during June 2021–December 2022 for cardiac or undetermined causes of death. For identified decedents, records in Oregon’s immunization information system were reviewed for documentation of mRNA COVID-19 vaccination received ≤100 days before death. Of 40 deaths that occurred among persons who had received an mRNA COVID-19 vaccine dose, three occurred ≤100 days after vaccination. Two of these deaths were attributed to chronic underlying conditions; the cause was undetermined for one. The authors conclude that the data does not support an association between receipt of mRNA COVID-19 vaccine and sudden cardiac death among previously healthy young persons. mm7314a5-H.pdf ( – April 11, 2024

This study using a mouse model with functional B cells and lymphoid organs but devoid of antibodies found that immunity conferred by prior infection or mRNA vaccination can protect against SARS-CoV-2 challenge independently of antibodies. CD8+ T cells are essential for combating severe infections, whereas CD4+ T cells contribute to managing milder cases, with interferon-γ having an important function in this antibody-independent defense. Antibody-independent protection against heterologous SARS-CoV-2 challenge conferred by prior infection or vaccination | Nature Immunology – March 14, 2024

This very small but randomized, double-blind, placebo controlled NIAID study in individuals 16-69 years old who previously reported a convincing systemic allergic reaction (sAR) to their first dose of mRNA vaccine found that a second dose of the Pfizer-BioNTech vaccine resulted in a sAR in 12.5% of subjects. Immunization stress-related response (ISRR) occurred more commonly and was associated with higher pre-dose qnxiety scores, paresthesias, and distinct vital sign ( increased heart rate and systolic BP) and biomarker (plasma free metanephrine and cortisol) changes.  Overall, severity of the sARs was greater following the first vaccine dose compared to the second and booster doses. Neither serum anti-PEG IgE nor vaccine skin testing was predictive of an sAR. “A randomized double-blinded trial to assess recurrence of systemic allergic reactions following COVID-19 mRNA vaccination” - ScienceDirect - March 7, 2024

The PROTECT study assessed COVID-19 vaccine knowledge, attitudes, and practices (KAP), and uptake over 15 months in 2,837 children. Findings of the current analysis suggest that these beliefs change over time and policies aiming to increase vaccine uptake should focus on vaccine safety and effectiveness. Longitudinal parental perception of COVID-19 vaccines for children in a multi-site, cohort study - PubMed ( – February 2024

A study reported in MMWR on children 6 months to 5 years in the v-safe monitoring system following a third dose of mRNA vaccine found similar reactions which had been reported after the first two vaccines. Safety Monitoring of mRNA COVID-19 Vaccine Third Doses Among Children Aged 6 Months–5 Years — United States, June 17, 2022–May 7, 2023 | MMWR (

This study in Pediatrics looked at data from safety surveillance in the Vaccine Safety Data Link (VSD) system (prospective data from 8 large health systems) on safety in approximately children under age 5 who had been given 250,000 doses of an mRNA vaccine. Risks were not elevated for any prespecified outcomes, including myocarditis/pericarditis. Safety of COVID-19 mRNA Vaccination Among Young Children in the Vaccine Safety Datalink | Pediatrics | American Academy of Pediatrics ( June 6, 2023

A prespecified interim analysis of a randomized clinical trial included 40,382 participants who received an inactivated vaccine series developed from either SARS-CoV-2 WIV04 (5 µg/dose) or HB02 (4 µg/dose) strains or an aluminum hydroxide–only control. The efficacy for the 2 vaccines, compared with an aluminum hydroxide–only control, was 72.8% in the WIV04 group and 78.1% in the HB02 group*; both comparisons were statistically significant. Two severe cases of COVID-19 occurred in the alum-only group and none occurred in the vaccine groups.  This may be an answer for those who are waiting for a "more conventional vaccine. (Effect of 2 Inactivated SARS-CoV-2 Vaccines on Symptomatic COVID-19 Infection in Adults: A Randomized Clinical Trial, May 26, 2021)  

This retrospective study among 95,000 VA patients during the Delta and Omicron periods found that vaccination was associated with lower odds of hospitalization, ICU admission, ventilation and death compared with no vaccination during both periods, although less so during the Omicron period, most likely due to overall less severity with Omicron infection. A third dose of mRNA vaccine was associated with additional risk reduction. Adverse outcomes of SARS-CoV-2 infection with delta and omicron variants in vaccinated versus unvaccinated US veterans: retrospective cohort study | The BMJ - May 23, 2023

In this decision analytical model using US population estimates, a simulation model revealed that booster campaigns achieving an uptake similar to seasonal influenza vaccination could have prevented an estimated 10 019 pediatric hospitalizations and 5 448 694 days of school absenteeism from October 1, 2022, to March 31, 2023. Estimated US Pediatric Hospitalizations and School Absenteeism Associated With Accelerated COVID-19 Bivalent Booster Vaccination | Infectious Diseases | JAMA Network Open | JAMA Network - May 19, 2023

A study in Scotland found that waning of the humoral response to vaccination was accelerated in those with obesity. Not only are such patients at higher risk of disease, but also more likely to require more frequent boosters. Accelerated waning of the humoral response to COVID-19 vaccines in obesity | Nature Medicine - May 11, 2023

A systematic review and meta-analysis of pooled randomized clinical trials found the incidence of Bell’s Palsy was significantly higher in vaccine vs. placebo patients. The risk of Bell’s Palsy with SARS-CoV-2 infection was even higher, however. Association of SARS-CoV-2 Vaccination or Infection With Bell Palsy: A Systematic Review and Meta-analysis | Facial Nerve | JAMA Otolaryngology–Head & Neck Surgery | JAMA Network - April 27, 2023

Regarding Long-Term Immunity: The lay press has perhaps overstated the findings of this June 2021 study to be published in Nature.  The researchers studied plasmablasts (PB) in the peripheral blood and germinal center B (GC B) cells in lymph node biopsies from 14 volunteers.  Findings: Circulating IgG- and IgA-secreting PBs targeting the S protein peaked one week after the second immunization then declined, becoming undetectable three weeks later. These PB responses preceded maximal levels of serum anti-S binding and neutralizing antibodies to an early circulating SARS-CoV-2 strain as well as emerging variants, especially in individuals previously infected with SARS-CoV-2, who produced the most robust serologic responses. By examining fine needle aspirates (FNAs) of draining axillary LNs, they identified GC B cells that bound S protein in all participants sampled after primary immunization. Remarkably, high frequencies of S-binding GC B cells and PBs were sustained in these draining LNs for at least twelve weeks after the booster immunization. SARS-CoV-2 mRNA vaccines induce persistent human germinal centre responses  

The NIH announced in April, 2021 a study assessing how people with immune system deficiencies or dysregulations respond to COVID-19 vaccination. The study will enroll participants 16 years of age and older, and potential participants can be referred by healthcare providers. All study visits will be conducted in person at the NIH Clinical Center or remotely. Participants can be enrolled before or after vaccination and can have received any of the approved vaccines.

British researchers have reported new data on the transmissibility of the new SARS-CoV-2 variant found in the UK and US. CDC officials have noted that the new variant appears unlikely to impact the effectiveness of the COVID-19 vaccine. The CDC is compiling information about the variants here. 

In this excellent opinion article on vaccines and variants, the authors point out several issues related to this problem, including issues with suboptimal immunity limiting the number or increasing the interval between doses, ability of vaccine-induced neutralizing antibodies to attack the virus, the loss of effectiveness of monoclonal antibodies against the variants, and then they propose an approach to the problem. JAMA, January 28

This recent article from the Lancet explains why multiple vaccines may be needed across different populations. -November 14, 2020

ACIP and ACOG recommend that vaccination should not be withheld from pregnant or lactating women, but they should be informed there are insufficient safety data available at this time. AAAAI research partner MotherToBaby has more information on the vaccine in pregnant and lactating women. 


Adverse Reactions

COVID-19 mRNA revaccination Is safe after allergic reaction to first dose, NIAID trial finds. A small NIAID clinical trial has found that receiving second and booster doses of a COVID-19 mRNA vaccine under medical supervision was safe for people who reported a systemic allergic reaction to their first dose. After revaccination, 12.5% of study participants had a systemic allergic reaction, while 62.5% had a non-allergic reaction that mimics anaphylaxis and is called Immunization Stress-Related Response (ISRR). These findings highlight the opportunity to assess and manage pre-vaccination anxiety to reduce ISRR. The Journal of Allergy and Clinical Immunology - March 27, 2024

An NIAID clinical trial is underway to study allergic reactions to the Moderna and Pfizer-BioNTech COVID-19 vaccines.  PDF icon A brief synopsis of the study is available herePDF icon A flyer about the study is available here.


The CDC has updated their guidance on administration of the SARS-CoV-2 mRNA vaccines with respect to pre-vaccine risks and post-vaccine reactions. The CDC has provided the following differentiation: 

  • Contraindication: History of a severe allergic reaction* (e.g., anaphylaxis) after a previous dose or to a component of the COVID-19 vaccine.
  • Precaution: Persons with any immediate allergic reaction to other (non-COVID-19) vaccines or injectable therapies OR a non-severe immediate allergic reaction (onset < 4 hours) after a previous dose of COVID-19 vaccine fall into this category.
    • Risk assessment/counseling with physician prior to second dose
    • 30 minute observation period after vaccination
    • Consider referral to allergist/immunologist
    • Immediate allergic reaction is defined as any hypersensitivity-related signs or symptoms such as urticaria, angioedema, respiratory distress (e.g., wheezing, stridor), or anaphylaxis that occur within four hours following administration. 
  • May proceed with COVID-19 vaccine: Persons with a history of food, pet, insect, venom, environmental, oral medication (including the oral equivalent of an injectable medication) or latex allergies, or a family history of allergies. 
    • 30-minute observation period for anyone with a history of anaphylaxis (due to any cause)
    • 15 minute observation for all others
    • Vial stoppers of mRNA vaccines are not made with natural rubber latex 
    • The mRNA vaccines do not contain egg or gelatin 

Multiple studies have demonstrated that patient with moderate or even severe allergic reactions to a previous mRNA vaccine can receive a second dose safely, with observation. Studies suggest that these reactions may not be IgE-mediated.

Other Reported Reactions

Thrombosis-Thrombocytopenia Syndrom (TTS) 

The Janssen vaccine authorization has been revoked by the FDA. Novavax vaccine is now considered an alternate vaccine of choice.

Thrombosis with Thrombocytopenia Syndrome (TTS) is a rare complication of vaccination with the J&J vaccine which presents with typical and atypical thromboses associated with thrombocytopenia.  Symptoms usually start between 6 and 15 days after vaccination. Most concerning is Cerebral Venous Sinus Thrombosis (CVST) which has been present in 54% of cases. All of the patients have required hospitalization, 66% have been admitted to the ICU, 17% have required post-hospital skilled nursing care and 15% have died (total of 9 patients confirmed as of 12/9/21). This can present with altered mental status, visual disturbances, hemiparesis, and seizures, and can rapidly progress from symptom onset to death. 

Although this is a very serious potential complication, it is also very rare. The overall reporting rate is 3.83 per million doses of J&J vaccine. The reporting rate varies among different age groups and sex.  Two-thirds of the cases have occurred in females. The group with the highest risk is 30-39 year-old females with a reporting rate of 10.60 per 1 million doses, closely followed by the 40-49-year-old female group with a reporting rate of 9.02/million doses. The reporting rate in both females and males over the age of 65 is low. The overall death reporting rate is 0.57/1 million doses but it 30-49-year old females, it is 1.80-1.93/1 million doses. Note: all cases have been reported through VAERS, so these may be underestimates.



Mild episodes of myocarditis have been rarely reported following mRNA vaccination. Recent reports suggest that this complication may be more common with the Moderna vaccine ( Most of the patients have been discharged from the hospital within 1-2 days and only treated with steroids or anti-inflammatories. At 3 months FU, 90% are considered fully recovered. There has been one death reported from New Zealand, but details are not currently known. Like the TTS, the reporting rate varies with age and sex with the highest risk group 18-49-year-old males with a rate of 13 cases per 1 million doses. The rate for 18-49-year-old females is 2/million doses, and for 50-64-year-old males and females, 1/million doses. There have not been any cases reported in females over 65 years-old, and 1/million in males over 65.

In the 5-11-year-old age range, out of 7,141,428 doses administered, there have been 8 confirmed cases with another 5 being investigated.

Guillain-Barre Syndrome  

The Janssen vaccine authorization has been revoked by the FDA. Novavax vaccine is now considered an alternate vaccine of choice.

This has only occurred at a higher rate following the J&J vaccine. Mortality has been about 1%, 10% have required mechanical ventilation.  Most recover, although some nerve deficits may occur. This typically presents two weeks after vaccination.  Data presented at the July 17th meeting of the ACIP noted the highest rate in males over the age of 50 with 16 cases per 1 million doses. In females over 65, rates are 9/million doses.  Among females 50-64-years-old, and males and females 18-49-years-old, the rates are 5-7 per million doses, slightly over the expected background rate. The risk/benefit ratio favors vaccination for this complication because of the higher risk for hospitalization in those over 50.


Vaccine safety

  • This study from Denmark looked at the rate of adverse reactions after receipt of the bivalent booster in 1,740,417 adults. Findings: no significant increased rate of adverse events in the 28 days after receipt, although post-hoc analysis noted a rare but significant signal of myocarditis but only in female participants. (In CDC safety monitoring programs, the myocarditis was mostly in males). Safety of BA.4-5 or BA.1 bivalent mRNA booster vaccines: nationwide cohort study | The BMJ - July 25, 2023

  • This nationwide population-based study in Korea involved almost 4 million people who had received an mRNA COVID-19 vaccine without previous infection compared to similar numbers of prepandemic historical control. The risk of autoimmune connective tissue disorders was no higher in the vaccinated patients compared to the controls. Risk of autoimmune skin and connective tissue disorders after mRNA-based COVID-19 vaccination - Journal of the American Academy of Dermatology ( May 13, 2023

  • Safety Monitoring of mRNA COVID-19 Vaccine Third Doses Among Children Aged 6 Months–5 Years — United States, June 17, 2022–May 7, 2023 | MMWR (

    Patients get mixed (and sometimes blatantly false) messages about the COVID-19 vaccine from news sources, family and friends. Concepts surrounding the need for clinical trials to demonstrate safety, efficacy, and dosing are challenging to understand for many. As our knowledge of the virus continues to grow and evolve, guidance from health experts changes, which leads to more confusion and suspicion. Studies show that patients trust their personal physicians, and allergists are in a position to explain the necessary steps involved in drug and vaccine discovery to patients in an effort to help them understand timeline, expectations, and why some early claims will not pan out. 

    Effective communication resources

  • The latest data show 61% of adults being vaccinated or intending to do so, while only 13% say they definitely will not get the vaccine (the "definitely will not" percent is unchanged since December). A number of statements were tested to see which led participants in the "wait and see" group to most likely say they would get vaccinated. Statements that were most impactful include: 
    • Vaccines are nearly 100% effective at preventing hospitalization and death from COVID-19. 
    • Scientists have been working on the technology used in the new COVID-19 vaccines for 20 years. 
    • More than 100,000 people from diverse backgrounds took part in the vaccine trials. 
    • The vast majority of doctors who have been offered the vaccine have taken it. 
    • There is no cost to get the vaccine. 

Other helpful information/resources

This cohort study from Europe using electronic health records compared over 10 million vaccinated individuals to over 10 million unvaccinated individuals and found that vaccination was associated with reduced risks of acute (30 day) and post-acute venous thromboembolism, arterial thrombosis and heart failure. The role of COVID-19 vaccines in preventing post-COVID-19 thromboembolic and cardiovascular complications | Heart ( - March 2024

A new release from the AAP dated 2/15/24 covers states that America’s leading physician organizations, representing 600,000 physicians, residents and medical students unequivocally support COVID-19 vaccines. The release was signed by the American Academy of Pediatrics, the American Academy of Family Physicians, the American College of Obstetrics and Gynecology, the American College of Physicians, the American Osteopathic Association, and the American Psychiatric Association. Read the news release here: America’s Leading Physician Groups Unequivocally Support COVID-19 Vaccines ( – February 15, 2024

This review article does a good job of covering vaccine hesitancy and the impact of social media and disinformation, as well as behavioral interventions to reduce hesitancy. Behavioural interventions to reduce vaccine hesitancy driven by misinformation on social media | The BMJ – January 16, 2024

Belief about the severity of a disease is one of the major factors in vaccine hesitancy. This VA survey compared outcomes following influenze vs. COVID-19 infection and found that the risk of death and several other adverse health outcomes was significantly higher following COVID-19 than influenza infection. Long-term outcomes following hospital admission for COVID-19 versus seasonal influenza: a cohort study - The Lancet Infectious Diseases - December 14, 2023

A national survey to query parents about their intention to vaccinate their children against COVID-19, influenza, and RSV in the fall and winter 2023-2024 found that about 40% of parents intended to vaccinate their children against COVID-19, 63% against influenza, and 71% against RSV. Intention to vaccinate was consistently correlated with concerns about the disease, trust in health institutions, and previous vaccinations. Major reasons for hesitancy include concerns about safety, necessity, and lack of information. Assessing parental intention to vaccinate against COVID-19, influenza, and RSV in the United States in late 2023 - ScienceDirect - December 7, 2023

What to tell your patients to do (and not do) with their vaccination cards:  
  • Cover up personal information and vaccine lot number before taking a selfie with the card,  
  • have a backup copy,  
  • skip card lamination, if a booster dose becomes necessary it will be hard to add onto a laminated card.  
  • replacement can be complicated,  
  • There's no easy access to the data,  
  • share vaccination status with your doctor. "Things to tell patients about their COVID-19 vaccine card" from the AMA 

The CDC is encouraging use of the v-safe smartphone tool to report any side effects that occur after receiving the COVID-19 vaccination. Patients are asked to complete surveys and health check-ins after the vaccination, and the tool will provide a reminder of a second dose if necessary. 

A discussion on Clinical Endpoints for Evaluating Efficacy in COVID-19 Vaccine Trials was published. (Ann Intern Med; October 22, 2020) 

Listen to episode 45 of the AAAAI podcast series: Addressing COVID-19 Vaccine Hesitancy. (March 24, 2021) 
The CDC has produced a comprehensive resource for providers on counseling patients about getting a vaccine, including communication points and ideas about proactive patient outreach. 

Recent articles from the AMA cover the Do’s and Don’ts for Talking with Patients about COVID-19 Vaccines and COVID Vaccine Hesitancy: 10 Tips for Talking with Patients 

The NIH Behavior and Social Sciences Research Coordinating committee has released resources on how to effectively communicate about the COVID-19 vaccine: 
COVID-19 Vaccination Communication 
A Communicator's Tip Sheet for COVID-19 Vaccination 
The CDC has also released training and educational materials for healthcare professionals. This includes information to guide conversations with and answer questions from patients regarding COVID-19 vaccines. 
Answers to the Top 6 Concerns about Vaccines from Your Local Epidemiologist.  Republished with permission from Katelyn Jetelina, MPH, PhD.
FDA: COVID-19 Vaccines

These sites offers some useful information on counseling vaccine hesitant patients: COVID-19 Vaccine Confidence | CDC  and Communication Resources | CDC Most of these links can be found on the “Stay Up to Date on Vaccines” site: Stay Up to Date with COVID-19 Vaccines | CDC