Natural reservoir

"Natural Immunity" from Omicron is Weak and Limited, Study Finds

Retrieved on: 
Wednesday, May 18, 2022

SAN FRANCISCO, May 18, 2022 /PRNewswire/ -- In unvaccinated people, infection with the Omicron variant of SARS-CoV-2 provides little long-term immunity against other variants, according to a new study by researchers at Gladstone Institutes and UC San Francisco (UCSF), published today in the journal Nature.

Key Points: 
  • In experiments using mice and blood samples from donors who were infected with Omicron, the team found that the Omicron variant induces only a weak immune response.
  • To find the answer, the team of researchers first examined the effect of Omicron in mice.
  • Compared to an ancestral strain of SARS-CoV-2 and the Delta variant, Omicron led to far fewer symptoms in the mice.
  • Samples from WA1-infected animals could neutralize Alpha and, to a lesser degree, the Beta and Delta virusbut not Omicron.