Carlos del Rio, MD, executive associate dean, Emory School of Medicine and Grady Health System, distinguished professor, Department of Medicine, Division of Infectious Disease, Emory University School of Medicine, professor, Hubert Department of Global Health-Rollins School of Public Health, co-director, Emory Center for AIDS Research, co-primary investigator, Emory-CDC HIV Clinical Trials Unit and the Emory Vaccine and Treatment Evaluation Unit, Emory Vaccine Center, discusses remaining questions with the COVID-19 vaccines.

With 2 different COVID-19 vaccines available for commercial use, questions surrounding duration of immunity and efficacy against different variants of the virus remain unknown, says del Rio. The clinical studies of the vaccines are still under way, so these questions are still in the process of being answered, del Rio says. 

Getting the vaccine to the general public was important despite these remaining questions because of the high morbidity and mortality associated with COVID-19, concludes del Rio.

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Carlos del Rio, MD, discusses remaining questions with the COVID-19 vaccines.  



Dr. del Rio on Remaining Questions With the COVID-19 Vaccines  

Carlos del Rio, MD, executive associate dean, Emory School of Medicine and Grady Health System, distinguished professor, Department of Medicine, Division of Infectious Disease, Emory University School of Medicine, professor, Hubert Department of Global Health-Rollins School of Public Health, co-director, Emory Center for AIDS Research, co-primary investigator, Emory-CDC HIV Clinical Trials Unit and the Emory Vaccine and Treatment Evaluation Unit, Emory Vaccine Center, discusses the reactogenicity of the COVID-19 vaccines.

In vaccinology, toxicity is different from reactogenicity, says del Rio. Adverse effects are medically relevant events associated with vaccination, whereas reactogenicity is the immune system’s reaction to the vaccine, del Rio says.

The COVID-19 vaccines appear to have slightly higher reactogenicity compared with the influenza vaccine, but significantly less reactogenicity vs the shingles vaccine, says del Rio. Oftentimes, patients who receive the COVID-19 vaccine will have a sore arm and erythema near the injection site, del Rio says. Some individuals report myalgia, fatigue, headache, and fever following vaccination; however, these reactions typically resolve after about 2 days and are a result of immune system activation, del Rio explains. Notably, these reactions tend to be worse following the second dose of vaccine in patients who haven’t had COVID-19 and following the first dose of vaccine in patients who have had COVID-19, concludes del Rio.

Carlos del Rio, MD, discusses the reactogenicity of the COVID-19 vaccines.  



Dr. del Rio on the Reactogenicity of the COVID-19 Vaccines 

Carlos del Rio, MD, executive associate dean, Emory School of Medicine and Grady Health System, distinguished professor, Department of Medicine, Division of Infectious Disease, Emory University School of Medicine, professor, Hubert Department of Global Health-Rollins School of Public Health, co-director, Emory Center for AIDS Research, co-primary investigator, Emory-CDC HIV Clinical Trials Unit and the Emory Vaccine and Treatment Evaluation Unit, Emory Vaccine Center, discusses factors to consider when selecting between available vaccines for COVID-19.

On December 11, 2020, the FDA granted Emergency Use Authorization to Pfizer’s BNT162b2 as the first vaccine to prevent COVID-19 in individuals aged 16 years and older. On December 18, 2020, the Moderna COVID-19 vaccine was granted the same designation for use in patients aged 18 years and older. Although no head-to-head comparative data exist, the vaccines appear to be similar in terms of efficacy and both are valid options, says del Rio. 

Additionally, another vaccine from Johnson & Johnson is poised for FDA review, says del Rio. Although the efficacy appears similar to the other approved vaccines, the Johnson & Johnson vaccine utilizes an adenovirus-based approach, whereas the others use mRNA technology, del Rio explains. Moreover, although all 3 options appear efficacious in terms of preventing severe COVID-19, the Johnson & Johnson vaccine appears to be less effective at preventing mild to moderate COVID-19, del Rio says. 

As such, immunocompromised individuals, such as patients with cancer, may have better outcomes with the Pfizer or Moderna vaccines, and healthy individuals may opt for the Johnson & Johnson vaccine should it receive Emergency Use Authorization from the FDA, concludes del Rio.

Carlos del Rio, MD, discusses factors to consider when selecting between available vaccines for COVID-19.  



Carlos del Rio, MD

Articles

Dr. del Rio on Remaining Questions With the COVID-19 Vaccines

Dr. del Rio on the Reactogenicity of the COVID-19 Vaccines

Dr. del Rio on Selecting Between Available Vaccines for COVID-19