How Effective is the Latest COVID-19 Vaccine?

February 02, 2024

The latest COVID-19 vaccine increased protection against symptomatic infection by about half, according to a new CDC report.

The report indicates the latest vaccine, which was updated to protect against XBB.1.5, offers protection against the main circulating variants in the U.S.

“Everything from this study is reassuring that the vaccines are providing the protection that we expected,” Ruth Link-Gelles, lead author of the new study, told CNN this week.

Here are the key takeaways:

• By the numbers:  The COVID-19 vaccine provided 54 percent increased protection against symptomatic infection when compared to those who did not receive the vaccine.
• The study: Researchers reviewed more than 9,200 pharmacy tests from September 2023–January 2024.  The researchers sought to distinguish protection against JN.1 and XBB-related lineages.
• Variants:  The virus appeared to provide protection against JN.1 and other circulating lineages, researchers found.
  • JN.1 is the main circulating variant, accounting for 93.1 percent of cases.
• State of the virus:  U.S. hospitalizations have declined nearly 11 percent (22,636) in the week ending January 27. About 2 percent of emergency department visits were for COVID-19, down 11 percent from the week prior.
• Bottom line:  “These data provide reassurance that updated vaccines are providing protection against JN.1 and XBB lineages,” the CDC report noted.

Additional information about the effectiveness of the COVID-19 is available online.