At present, JAMA Inner Medication revealed a research calculating the safety provided by the newest Pfizer COVID-19 XBB vaccine in comparison with older vaccines towards COVID-associated hospitalization and emergency division (ED) or pressing care (UC) visits.
The test-negative case-control research of the BNT162b2 XBB vaccine was carried out amongst adults within the Kaiser Permanente Southern California well being system from October 10 to December 10, 2023. XBB was the dominant pressure of SARS-CoV-2 in america at the moment however has since been supplanted by JN.1.
The research included sufferers who offered with an acute respiratory sickness and had a optimistic SARS-CoV-2 polymerase chain response check and controls who had an acute respiratory sickness however examined destructive for SARS-CoV-2. A complete of two,854 circumstances and 15,345 controls (median age, 56) had been included within the research.
The authors in contrast outcomes amongst those that had obtained an up to date XBB vaccine and people who had not obtained an XBB vaccine of any type, no matter prior COVID-19 vaccination or an infection historical past.
“Receipt of prior (non-XBB) variations of COVID-19 vaccines was additionally in contrast with being unvaccinated to estimate remaining safety from older vaccines,” the authors mentioned.
62% safety towards hospitalization
In comparison with those that had not obtained an up to date XBB vaccine, recipients had 62% safety towards COVID-19 hospitalization (95% confidence interval [CI], 32% to 79%). Safety was 58% towards ED/UC visits (95% CI, 48% to 67%).
A historical past of vaccination with pre-XBB vaccines didn’t considerably cut back the danger of COVID-19 outcomes, together with hospital admission, and outcomes had been much like these of unvaccinated sufferers.
The median time between vaccination with a non-XBB vaccine and sickness was 1 to 2 years, whereas the median time between vaccination with an XBB vaccine and sickness was 34 days.
The mix of waning vaccine-induced immunity and steady SARS-CoV-2 pressure evolution ultimately renders prior variations of vaccines ineffective.
“The current findings assist reaffirm present suggestions for broad age-based use of yearly up to date COVID-19 vaccines within the US to enhance safety towards COVID-19 every year previous to seemingly winter peaks in illness exercise,” the authors concluded. “The mix of waning vaccine-induced immunity and steady SARS-CoV-2 pressure evolution ultimately renders prior variations of vaccines ineffective.”
In an invited commentary on the research, Gopi Mohan, MD, PhD, of the College of Texas MD Anderson Most cancers Middle, and others, write, “These findings illuminate the difficulty of waning immunity and level to the significance of standard boosting along with updating vaccine formulations.”
