Omicron extensively but incompletely escapes Pfizer BNT162b2 neutralization
Sandile Cele, Laurelle Jackson, David S. Khoury, Khadija Khan, Thandeka Moyo-Gwete, Houriiyah Tegally, James Emmanuel San, Deborah Cromer, Cathrine Scheepers, Daniel G. Amoako, Farina Karim, Mallory Bernstein, Gila Lustig, Derseree Archary, Muneerah Smith, Yashica Ganga, Zesuliwe Jule, Kajal Reedoy, Shi-Hsia Hwa, Jennifer Giandhari, Jonathan M. Blackburn, Bernadett I. Gosnell, Salim S. Abdool Karim, Willem A. Hanekom, NGS-SA, Mary‐Ann Davies, Marvin Hsiao, Darren P. Martin, Koleka Mlisana, Constantinos Kurt Wibmer, Carolyn Williamson, Denis York, COMMIT-KZN Team, Rohen Harrichandparsad, Kobus Herbst, Prakash Jeena, Thandeka Khoza, Henrik N. Kløverpris, Alasdair Leslie, Rajhmun Madansein, Nombulelo Magula, Nithendra Manickchund, Mohlopheni J. Marakalala, Matilda Mazibuko, Mosa Moshabela, Ntombifuthi Mthabela, Kogie Naidoo, Zaza M. Ndhlovu, Thumbi Ndung’u, Nokuthula Ngcobo, Kennedy Nyamande, Vinod Patel, Theresa Smit, Adrie J. C. Steyn, Emily Wong, Anne von Gottberg, Jinal N. Bhiman, Richard Lessells, Mahomed‐Yunus S. Moosa, Miles P. Davenport, Túlio de Oliveira, Penny L. Moore, Alex Sigal
Abstract
. Here we investigated Omicron escape from neutralization by antibodies from South African individuals vaccinated with Pfizer BNT162b2. We used blood samples taken soon after vaccination from individuals who were vaccinated and previously infected with SARS-CoV-2 or vaccinated with no evidence of previous infection. We isolated and sequence-confirmed live Omicron virus from an infected person and observed that Omicron requires the angiotensin-converting enzyme 2 (ACE2) receptor to infect cells. We compared plasma neutralization of Omicron relative to an ancestral SARS-CoV-2 strain and found that neutralization of ancestral virus was much higher in infected and vaccinated individuals compared with the vaccinated-only participants. However, both groups showed a 22-fold reduction in vaccine-elicited neutralization by the Omicron variant. Participants who were vaccinated and had previously been infected exhibited residual neutralization of Omicron similar to the level of neutralization of the ancestral virus observed in the vaccination-only group. These data support the notion that reasonable protection against Omicron may be maintained using vaccination approaches.