COVID-19 Roundup: CDC/FDA Say No Booster Shot Needed Now; Benefits of Vaccines Outweigh Rare Heart Risk; and Study Looks at 'Viral Load'

CDC and FDA: No COVID-19 Booster Shot is Needed at This Time — Even Against Delta Variant

A booster shot for further protection against COVID-19 is not needed at this time, according to a joint statement by the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA).

“People who are fully vaccinated are protected from severe disease and death, including from the variants currently circulating in the country such as Delta,” the FDA and CDC said.

Such a joint statement from the CDC and FDA is rare. This one followed an announcement by Pfizer and BioNTech which stated they are developing a COVID-19 booster shot that would target the delta variant, which is becoming the dominant and most highly transmissible strain of the coronavirus in the U.S. and worldwide.

Pfizer-BioNTech, along with Moderna’s vaccine, provide the currently available, two-shot mRNA vaccines against COVID-19. Recent studies have shown that both vaccines remain effective against variants, primarily preventing severe disease or hospitalizations.

The CDC and FDA statement: “Americans who have been fully vaccinated do not need a booster shot at this time. FDA, CDC, and [the National Institutes of Health] are engaged in a science-based, rigorous process to consider whether or when a booster might be necessary,” the agencies added. “We continue to review any new data as it becomes available and will keep the public informed. We are prepared for booster doses if and when the science demonstrates that they are needed.”

Pfizer and BioNTech said in a statement Thursday that while their current two-dose vaccine has the potential to preserve the “highest levels” of protection against all known variants, including delta, they are “remaining vigilant” and developing an updated version of the vaccine.

“As seen in real world evidence released from the Israel Ministry of Health, vaccine efficacy has declined six months post-vaccination, at the same time that the delta variant is becoming the dominate variant in the country,” the companies said in a written statement.

Earlier this week, Israeli officials reported research findings that found a decrease in the effectiveness of the Pfizer-BioNTech vaccine over six months in preventing infections and symptomatic illness — but the vaccine remains highly effective in preventing serious illness, hospitalization and death.

Even before the full emergence of the delta variant, Pfizer-BioNTech has said that a booster shot would likely be needed up to a year after receiving the initial two-shot regiment. “We continue to believe, that it is likely, based on the totality of the data we have to date, that a third dose may be needed within 6 to 12 months after full vaccination,” the companies said this week.

CDC: Benefits of Pfizer, Moderna Vaccines ‘Cleary Outweigh’ Heart Inflammation Risk

After an extensive review of data, a key group of immunization experts for the U.S. Centers for Disease Control and Prevention (CDC) has concluded that the benefits of the COVID-19 vaccines from Moderna and Pfizer-BioNTech “clearly outweigh” any increased risks of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the tissue surrounding the heart).

Myocarditis and pericarditis — still very rare following vaccinations — typically occur more often in males than in females, and incidence is highest among infants, adolescents, and young adults. However, the benefits — “prevention of COVID-19 disease and associated hospitalizations, ICU admissions, and deaths ” — outweigh the risks (expected myocarditis cases after vaccination) in all populations for which vaccination has been recommended, according to the CDC’s Advisory Committee on Immunization Practices (ACIP).

The CDC had identified more than 1,200 cases of a myocarditis or pericarditis mostly in people 30 or young who received the two shots of either the Moderna or Pfizer vaccines. The vast majority of these individuals have recovered. Myocarditis and pericarditis typically can be successfully treated and monitored.

“No alternatives to the mRNA COVID-19 vaccines (from Moderna and Pfizer) for adolescents will be available for the foreseeable future, and vaccination of adolescents offers protection against COVID-19 that can be important for returning to educational, social, and extracurricular activities,” the CDC states.

The CDC said it is continuing to monitor outcomes of myocarditis cases after COVID-19 vaccination. Last month, the U.S. Food and Drug Administration revised its guidelines for the Moderna and Pfizer-BioNTech COVID-19 vaccines, adding that there may be increased risks of myocarditis and pericarditis following vaccinations.

CDC: Vaccinated People Fare This Much Better Than Unvaccinated If They Get COVID-19

People who became infected with COVID-19 after getting the so-called mRNA vaccines — from Moderna and Pfizer-BioNTech — carried less of a “viral load” and had milder cases than unvaccinated people who became infected, according to a new study by researchers at the U.S. Centers for Disease Control and Prevention (CDC).

Carrying less of a viral load means that those individuals are less likely to transmit the virus to others, compared to unvaccinated people, the study said.

The research team followed 3,975 healthcare workers and first responders who underwent weekly testing between December 2020 and April 2021. COVID-19 was detected in 204 participants, including five who were fully vaccinated and 11 who were partially vaccinated, with either the Moderna or Pfizer vaccines.

Those who were fully or partially vaccinated showed a 40 percent lower viral load than their unvaccinated counterparts. They also had a 66 percent lower risk of carrying a detectable virus for more than one week. Those vaccinated also carried a 58 percent lower risk of COVID-19 symptoms, compared to those who were not vaccinated.

None of the vaccinated study participants who contracted COVID-19 were hospitalized — with all of them experiencing only mild or moderate symptoms. Those vaccinated also had a shorter duration of illness — about two fewer days spent sick in bed and six fewer days of symptoms, compared to unvaccinated study participants.

“Authorized mRNA vaccines (from Moderna and Pfizer-BioNTech) were highly effective among working-age adults in preventing COVID-19 infection when administered in real-world conditions,” the researchers concluded. “And the vaccines attenuated the viral RNA load, risk of febrile symptoms, and duration of illness among those who had breakthrough infection despite vaccination.”