Although there is evidence that depicts the COVID-19 booster shot's effectiveness against the virus, the Centers for Disease Control published a report Friday stating that its potency only lasts around four months.

The agency still urges all people above the age of 12 to get boosted five months after getting the first two doses of the Pfizer or Moderna mRNA vaccines. The CDC also underlined its “clinical preference for individuals to receive an mRNA COVID-19 vaccine over Johnson & Johnson’s COVID-19 vaccine” in December 2021.

Efficacy rates fell to 66% and 78% from around 90% by the fourth month after a third dose, but CDC spokesperson Kristen Nordlund stressed that the“Covid-19 vaccine boosters remain safe and continue to be highly effective against severe disease over time.”

CDC Director Dr. Rochelle Walensky also clarified that “those who received a booster dose had the most protection against emergency room visits, urgent care clinic visits, and hospitalizations.”

The CDC's Advisory Committee on Immunization Practices found that young men, including teenagers, have the highest chances of developing myocarditis, or heart inflammation, after getting the second dose of either mRNA vaccine, with a larger risk of cases amongst those getting the Moderna shot.