Lab interests
We are interested in emerging and re-emerging viral infections, how they evolve and how they manipulate infected cells. Specific research areas include how persistent infections in immunosuppressed individuals lead to viral evolution.
Lab PI and members
Alex Sigal is faculty at the Africa Health Research Institute and the University of KwaZulu-Natal. Alex has a PhD in Systems Biology from the Weizmann Institute and was a postdoctoral fellow with David Baltimore at the California Institute of Technology. Lab staff: Dr. Khadija Khan, who leads many of the projects, Yashica Ganga, Zesuliwe Jule, and Kajal Reedoy. We work closely with Dr. Farina Karim at AHRI and Prof. Yunus Moosa at the University of KwaZulu-Natal.
Publications
2024
Karim, F., Riou, C., Bernstein, M., Jule, Z., Lustig, G., van Graan, S., Keeton, R. S., Upton, J. L., Ganga, Y., Khan, K., Reedoy, K., Mazibuko, M., Govender, K., Thambu, K., Ngcobo, N., Venter, E., Makhado, Z., Hanekom, W., von Gottberg, A., Hoque, M., Karim, Q. A., Abdool Karim, S. S., Manickchund, N., Magula, N., Gosnell, B. I., Lessells, R. J., Moore, P. L., Burgers, W. A., de Oliveira, T., Moosa, M. S., Sigal, A. Clearance of persistent SARS-CoV-2 associates with increased neutralizing antibodies in advanced HIV disease post-ART initiation. Nature Communications.
Riou C, Bhiman JN, Ganga Y, Sawry S, Ayres F, Baguma R, Balla SR, Benede N, Bernstein M, Besethi AS, Cele S, Crowther C, Dhar M, Geyer S, Gill K, Grifoni A, Hermanus T, Kaldine H, Keeton RS, Kgagudi P, Khan K, Lazarus E, Le Roux J, Lustig G, Madzivhandila M, Magugu SFJ, Makhado Z, Manamela NP, Mkhize Q, Mosala P, Motlou TP, Mutavhatsindi H, Mzindle NB, Nana A, Nesamari R, Ngomti A, Nkayi AA, Nkosi TP, Omondi MA, Panchia R, Patel F, Sette A, Singh U, van Graan S, Venter EM, Walters A, Moyo-Gwete T, Richardson SI, Garrett N, Rees H, Bekker LG, Gray G, Burgers WA, Sigal A, Moore PL, Fairlie L. Safety and immunogenicity of booster vaccination and fractional dosing with Ad26.COV2.S or BNT162b2 in Ad26.COV2.S-vaccinated participants. PLOS Glob Public Health.
Jaumdally S, Tomasicchio M, Pooran A, Esmail A, Kotze A, Meier S, Wilson L, Oelofse S, van der Merwe C, Roomaney A, Davids M, Suliman T, Joseph R, Perumal T, Scott A, Shaw M, Preiser W, Williamson C, Goga A, Mayne E, Gray G, Moore P, Sigal A, Limberis J, Metcalfe J, Dheda K. Frequency, kinetics and determinants of viable SARS-CoV-2 in bioaerosols from ambulatory COVID-19 patients infected with the Beta, Delta or Omicron variants. Nature Communications.
Mühlemann B, Wilks SH, Baracco L, Bekliz M, Carreño JM, Corman VM, Davis-Gardner ME, Dejnirattisai W, Diamond MS, Douek DC, Drosten C, Eckerle I, Edara V-V, Ellis M, Fouchier RAM, Frieman M, Godbole S, Haagmans B, Halfmann PJ, Henry AR, Jones TC, Katzelnick LC, Kawaoka Y, Kimpel J, Krammer F, Lai L, Liu C, Lusvarghi S, Meyer B, Mongkolsapaya J, Montefiori DC, Mykytyn A, Netzl A, Pollett S, Rössler A, Screaton GR, Shen X, Sigal A, Simon V, Subramanian R, Supasa P, Suthar MS, Türeli S, Wang W, Weiss CD, Smith DJ. Comparative analysis of SARS-CoV-2 neutralization titers reveals consistency between human and animal model serum and across assays. Science Translational Medicine.
Tomasicchio, M., Jaumdally, S., Wilson, L., Kotze, A., Semple, L., Meier, S., Pooran, A., Esmail, A., Pillay, K., Roberts, R., Kriel, R., Meldau, R., Oelofse, S., Mandviwala, C., Burns, J., Londt, R., Davids, M., van der Merwe, C., Roomaney, A., Kühn, L., Perumal, T., Scott, A. J., Hale, M. J., Baillie, V., Mahtab, S., Williamson, C., Joseph, R., Sigal, A., Joubert, I., Piercy, J., Thomson, D., Fredericks, D. L., Miller, M. G., Nunes, M. C., Madhi, S. A. & Dheda, K. SARS-CoV-2 Viral Replication Persists in the Human Lung for Several Weeks after Symptom Onset. Am J Respir Crit Care Med.
Ng’uni, T. L., Musale, V., Nkosi, T., Mandolo, J., Mvula, M., Michelo, C., Karim, F., Moosa, M. Y. S., Khan, K., Jambo, K. C., Hanekom, W., Sigal, A., Kilembe, W. & Ndhlovu, Z. M. Low pre-existing endemic human coronavirus (HCoV-NL63)-specific T cell frequencies are associated with impaired SARS-CoV-2-specific T cell responses in people living with HIV. Frontiers in Immunology.
2023
Lustig, G., Ganga, Y., Rodel, H. E., Tegally, H., Khairallah, A., Jackson, L., Cele, S., Khan, K., Jule, Z., Reedoy, K., Karim, F., Bernstein, M., Ndung’u, T., Moosa, M.-Y. S., Archary, D., de Oliveira, T., Lessells, R., Neher, R. A., Abdool Karim, S. S. & Sigal, A. SARS-CoV-2 infection in immunosuppression evolves sub-lineages which independently accumulate neutralization escape mutations. SARS-CoV-2 infection in immunosuppression evolves sub-lineages which independently accumulate neutralization escape mutations. Virus Evolution.
Khan K, Lustig G, Römer C, Reedoy K, Jule Z, Karim F, Ganga Y, Bernstein M, Baig Z, Jackson L, Mahlangu B, Mnguni A, Nzimande A, Stock N, Kekana D, Ntozini B, van Deventer C, Marshall T, Manickchund N, Gosnell BI, Lessells RJ, Karim QA, Abdool Karim SS, Moosa MS, de Oliveira T, von Gottberg A, Wolter N, Neher RA, Sigal A. Evolution and neutralization escape of the SARS-CoV-2 BA.2.86 subvariant. Nature Communications.
Krause R, Snyman J, Shi-Hsia H, Muema D, Karim F, Ganga Y, Ngoepe A, Zungu Y, Gazy I, Bernstein M, Khan K, Mazibuko M, Mthabela N, Ramjit D; COMMIT-KZN Team; Limbo O, Jardine J, Sok D, Wilson IA, Hanekom W, Sigal A, Kløverpris H, Ndung’u T, Leslie A. HIV skews the SARS-CoV-2 B cell response towards an extrafollicular maturation pathway. eLife.
Hysenaj L, Little S, Kulhanek K, Magnen M, Bahl K, Gbenedio OM, Prinz M, Rodriguez L, Andersen C, Rao AA, Shen A, Lone JC, Lupin-Jimenez LC, Bonser LR, Serwas NK, Mick E, Khalid MM, Taha TY, Kumar R, Li JZ, Ding VW, Matsumoto S, Maishan M, Sreekumar B, Simoneau C, Nazarenko I, Tomlinson MG, Khan K, von Gottberg A, Sigal A, Looney MR, Fragiadakis GK, Jablons DM, Langelier CR, Matthay M, Krummel M, Erle DJ, Combes AJ, Sil A, Ott M, Kratz JR, Roose JP. SARS-CoV-2 infection of airway organoids reveals conserved use of Tetraspanin-8 by Ancestral, Delta, and Omicron variants. Stem Cell Reports.
Hao L, Hsiang TY, Dalmat RR, Ireton R, Morton JF, Stokes C, Netland J, Hale M, Thouvenel C, Wald A, Franko NM, Huden K, Chu HY, Sigal A, Greninger AL, Tilles S, Barrett LK, Van Voorhis WC, Munt J, Scobey T, Baric RS, Rawlings DJ, Pepper M, Drain PK, Gale M Jr. Dynamics of SARS-CoV-2 VOC Neutralization and Novel mAb Reveal Protection against Omicron. Viruses.
Krause RGE, Moyo-Gwete T, Richardson SI, Makhado Z, Manamela NP, Hermanus T, Mkhize NN, Keeton R, Benede N, Mennen M, Skelem S, Karim F, Khan K, Riou C, Ntusi NAB, Goga A, Gray G, Hanekom W, Garrett N, Bekker LG, Groll A, Sigal A, Moore PL, Burgers WA, Leslie A. Infection pre-Ad26.COV2.S-vaccination primes greater class switching and reduced CXCR5 expression by SARS-CoV-2-specific memory B cells. NPJ Vaccines.
Kaufmann SHE, Sigal A, Sawitzki B, Sher A. Editorial: The Covid-19 and TB syndemic: differences and similarities. Front Immunol.
Allué-Guardia A, Torrelles JB, Sigal A. Tuberculosis and COVID-19 in the elderly: factors driving a higher burden of disease. Front Immunol.
Sigal, A. Boosting in the age of Omicron. eLife.
Tan, Chee Wah, Zhu, Feng, Chia, Wan Ni, Young, Barnaby E., Yeoh, Aileen Ying Yan, Althaus, Thomas, Yung, Chee Fu, Yap, Wee Chee, Lim, Beng Lee, Chen, Mark I. C., Zhang, Jinyan, Mah, Yun Yan, Voiglio, Eric, Sigal, Alex, Huo, Jianxin, Xu, Shengli, Tan, Yee Joo, Lam, Kong-Peng, Lye, David, Wang, Lin-Fa. Distinctive serotypes of SARS-related coronaviruses defined by convalescent sera from unvaccinated individuals. hLife.
Naicker N, Rodel H, Perumal R, Ganga Y, Bernstein M, Benede N, Abdool Karim S, Padayacthi N, Sigal A, Naidoo K. Metformin Increases Cell Viability and Regulates Pro-Inflammatory Response to Mtb. Infect Drug Resist.
2022
Cele, S., Jackson, L., Khoury, D. S., Khan, K., Moyo-Gwete, T., Tegally, H., San, J. E., Cromer, D., Scheepers, C., Amoako, D. G., Karim, F., Bernstein, M., Lustig, G., Archary, D., Smith, M., Ganga, Y., Jule, Z., Reedoy, K., Hwa, S. H., Giandhari, J., Blackburn, J. M., Gosnell, B. I., Abdool Karim, S. S., Hanekom, W., von Gottberg, A., Bhiman, J. N., Lessells, R. J., Moosa, M. S., Davenport, M. P., de Oliveira, T., Moore, P. L. & Sigal, A. Omicron extensively but incompletely escapes Pfizer BNT162b2 neutralization. Nature.
Cele, S., Karim, F., Lustig, G., San, J. E., Hermanus, T., Tegally, H., Snyman, J., Moyo-Gwete, T., Wilkinson, E., Bernstein, M., Khan, K., Hwa, S. H., Tilles, S. W., Singh, L., Giandhari, J., Mthabela, N., Mazibuko, M., Ganga, Y., Gosnell, B. I., Karim, S. S. A., Hanekom, W., Van Voorhis, W. C., Ndung’u, T., Lessells, R. J., Moore, P. L., Moosa, M. S., de Oliveira, T. & Sigal, A. SARS-CoV-2 prolonged infection during advanced HIV disease evolves extensive immune escape. Cell Host & Microbe.
Khan, K., Karim, F., Cele, S., Reedoy, K., San, J. E., Lustig, G., Tegally, H., Rosenberg, Y., Bernstein, M., Jule, Z., Ganga, Y., Ngcobo, N., Mazibuko, M., Mthabela, N., Mhlane, Z., Mbatha, N., Miya, Y., Giandhari, J., Ramphal, Y., Naidoo, T., Sivro, A., Samsunder, N., Kharsany, A. B. M., Amoako, D., Bhiman, J. N., Manickchund, N., Karim, Q. A., Magula, N., Abdool Karim, S. S., Gray, G., Hanekom, W., von Gottberg, A., Milo, R., Gosnell, B. I., Lessells, R. J., Moore, P. L., de Olveira, T., Moosa, M. S. & Sigal, A. Omicron infection enhances Delta antibody immunity in vaccinated persons. Nature.
Sigal, A., Milo, R. & Jassat, W. Estimating disease severity of Omicron and Delta SARS-CoV-2 infections. Nature Reviews Immunology.
Sigal, A. Milder disease with Omicron: is it the virus or the pre-existing immunity? Nature Reviews Immunology.
Khan, K., Karim, F., Ganga, Y., Bernstein, M., Jule, Z., Reedoy, K., Cele, S., Lustig, G., Amoako, D., Wolter, N., Samsunder, N., Sivro, A., San, J. E., Giandhari, J., Tegally, H., Pillay, S., Naidoo, Y., Mazibuko, M., Miya, Y., Ngcobo, N., Manickchund, N., Magula, N., Karim, Q. A., von Gottberg, A., Abdool Karim, S. S., Hanekom, W., Gosnell, B. I., Lessells, R. J., de Oliveira, T., Moosa, M. S. & Sigal, A. Omicron BA.4/BA.5 escape neutralizing immunity elicited by BA.1 infection. Nature Communications.
Wells, G., Glasgow, J. N., Nargan, K., Lumamba, K., Madansein, R., Maharaj, K., Perumal, L. Y., Matthew, M., Hunter, R. L., Pacl, H., Peabody Lever, J. E., Stanford, D. D., Singh, S. P., Bajpai, P., Manne, U., Benson, P. V., Rowe, S. M., le Roux, S., Sigal, A., Tshibalanganda, M., Wells, C., du Plessis, A., Msimang, M., Naidoo, T. & Steyn, A. J. C. A high-resolution 3D atlas of the spectrum of tuberculous and COVID-19 lung lesions. EMBO Mol Med.
Krause, R., Snyman, J., Shi-Hsia, H., Muema, D., Karim, F., Ganga, Y., Ngoepe, A., Zungu, Y., Gazy, I., Bernstein, M., Khan, K., Mazibuko, M., Mthabela, N., Ramjit, D., Limbo, O., Jardine, J., Sok, D., Wilson, I. A., Hanekom, W., Sigal, A., Kløverpris, H., Ndung’u, T. & Leslie, A. HIV skews the SARS-CoV-2 B cell response toward an extrafollicular maturation pathway. eLife.
Greaney, A. J., Eguia, R. T., Starr, T. N., Khan, K., Franko, N., Logue, J. K., Lord, S. M., Speake, C., Chu, H. Y., Sigal, A. & Bloom, J. D. The SARS-CoV-2 Delta variant induces an antibody response largely focused on class 1 and 2 antibody epitopes. PLoS Pathogens.
Hwa, S. H., Snyman, J., Bernstein, M., Ganga, Y., Cele, S., Muema, D., Tan, C. W., Khan, K., Karim, F., Hanekom, W., Bernstein, L., Kaufmann, S. H. E., Wang, L. F., Ndung’u, T. & Sigal, A. HIV viremia is associated with compromised SARS-CoV-2 Beta variant neutralization. J Infect. Dis.
Nkosi, T., Chasara, C., Papadopoulos, A. O., Nguni, T. L., Karim, F., Moosa, M. S., Gazy, I., Jambo, K., Hanekom, W., Sigal, A. & Ndhlovu, Z. M. Unsuppressed HIV infection impairs T cell responses to SARS-CoV-2 infection and abrogates T cell cross-recognition. eLife.
Keeton, R., Tincho, M. B., Ngomti, A., Baguma, R., Benede, N., Suzuki, A., Khan, K., Cele, S., Bernstein, M., Karim, F., Madzorera, S. V., Moyo-Gwete, T., Mennen, M., Skelem, S., Adriaanse, M., Mutithu, D., Aremu, O., Stek, C., du Bruyn, E., Van Der Mescht, M. A., de Beer, Z., de Villiers, T. R., Bodenstein, A., van den Berg, G., Mendes, A., Strydom, A., Venter, M., Giandhari, J., Naidoo, Y., Pillay, S., Tegally, H., Grifoni, A., Weiskopf, D., Sette, A., Wilkinson, R. J., de Oliveira, T., Bekker, L. G., Gray, G., Ueckermann, V., Rossouw, T., Boswell, M. T., Bhiman, J. N., Moore, P. L., Sigal, A., Ntusi, N. A. B., Burgers, W. A. & Riou, C. T cell responses to SARS-CoV-2 spike cross-recognize Omicron. Nature.
Meng, B., Abdullahi, A., Ferreira, I., Goonawardane, N., Saito, A., Kimura, I., Yamasoba, D., Gerber, P. P., Fatihi, S., Rathore, S., Zepeda, S. K., Papa, G., Kemp, S. A., Ikeda, T., Toyoda, M., Tan, T. S., Kuramochi, J., Mitsunaga, S., Ueno, T., Shirakawa, K., Takaori-Kondo, A., Brevini, T., Mallery, D. L., Charles, O. J., Bowen, J. E., Joshi, A., Walls, A. C., Jackson, L., Martin, D., Smith, K. G. C., Bradley, J., Briggs, J. A. G., Choi, J., Madissoon, E., Meyer, K. B., Mlcochova, P., Ceron-Gutierrez, L., Doffinger, R., Teichmann, S. A., Fisher, A. J., Pizzuto, M. S., de Marco, A., Corti, D., Hosmillo, M., Lee, J. H., James, L. C., Thukral, L., Veesler, D., Sigal, A., Sampaziotis, F., Goodfellow, I. G., Matheson, N. J., Sato, K. & Gupta, R. K. Altered TMPRSS2 usage by SARS-CoV-2 Omicron impacts infectivity and fusogenicity. Nature.
Reuschl, A. K., Mesner, D., Shivkumar, M., Whelan, M. V. X., Pallett, L. J., Guerra-Assunção, J. A., Madansein, R., Dullabh, K. J., Sigal, A., Thornhill, J. P., Herrera, C., Fidler, S., Noursadeghi, M., Maini, M. K. & Jolly, C. HIV-1 Vpr drives a tissue residency-like phenotype during selective infection of resting memory T cells. Cell Reports.
Greaney, A. J., Starr, T. N., Eguia, R. T., Loes, A. N., Khan, K., Karim, F., Cele, S., Bowen, J. E., Logue, J. K., Corti, D., Veesler, D., Chu, H. Y., Sigal, A. & Bloom, J. D. A SARS-CoV-2 variant elicits an antibody response with a shifted immunodominance hierarchy. PLoS Pathogens.
Martin, D. P., Lytras, S., Lucaci, A. G., Maier, W., Grüning, B., Shank, S. D., Weaver, S., MacLean, O. A., Orton, R. J., Lemey, P., Boni, M. F., Tegally, H., Harkins, G. W., Scheepers, C., Bhiman, J. N., Everatt, J., Amoako, D. G., San, J. E., Giandhari, J., Sigal, A., Williamson, C., Hsiao, N. Y., von Gottberg, A., De Klerk, A., Shafer, R. W., Robertson, D. L., Wilkinson, R. J., Sewell, B. T., Lessells, R., Nekrutenko, A., Greaney, A. J., Starr, T. N., Bloom, J. D., Murrell, B., Wilkinson, E., Gupta, R. K., de Oliveira, T. & Kosakovsky Pond, S. L. Selection Analysis Identifies Clusters of Unusual Mutational Changes in Omicron Lineage BA.1 That Likely Impact Spike Function. Molecular Biology and Evolution.
Scheepers, C., Everatt, J., Amoako, D. G., Tegally, H., Wibmer, C. K., Mnguni, A., Ismail, A., Mahlangu, B., Lambson, B. E., Martin, D. P., Wilkinson, E., San, J. E., Giandhari, J., Manamela, N., Ntuli, N., Kgagudi, P., Cele, S., Richardson, S. I., Pillay, S., Mohale, T., Ramphal, U., Naidoo, Y., Khumalo, Z. T., Kwatra, G., Gray, G., Bekker, L. G., Madhi, S. A., Baillie, V., Van Voorhis, W. C., Treurnicht, F. K., Venter, M., Mlisana, K., Wolter, N., Sigal, A., Williamson, C., Hsiao, N. Y., Msomi, N., Maponga, T., Preiser, W., Makatini, Z., Lessells, R., Moore, P. L., de Oliveira, T., von Gottberg, A. & Bhiman, J. N. Emergence and phenotypic characterization of the global SARS-CoV-2 C.1.2 lineage. Nature Communications.
Tan, C. W., Chia, W. N., Zhu, F., Young, B. E., Chantasrisawad, N., Hwa, S. H., Yeoh, A. Y., Lim, B. L., Yap, W. C., Pada, S., Tan, S. Y., Jantarabenjakul, W., Toh, L. K., Chen, S., Zhang, J., Mah, Y. Y., Chen, V. C., Chen, M. I., Wacharapluesadee, S., Sigal, A., Putcharoen, O., Lye, D. C. & Wang, L. F. SARS-CoV-2 Omicron variant emerged under immune selection. Nat Microbiol.
2021
Cele, S., Gazy, I., Jackson, L., Hwa, S. H., Tegally, H., Lustig, G., Giandhari, J., Pillay, S., Wilkinson, E., Naidoo, Y., Karim, F., Ganga, Y., Khan, K., Bernstein, M., Balazs, A. B., Gosnell, B. I., Hanekom, W., Moosa, M. S., Network for Genomic Surveillance in South, A., Team, C.-K., Lessells, R. J., de Oliveira, T. & Sigal, A. Escape of SARS-CoV-2 501Y.V2 from neutralization by convalescent plasma. Nature.
Khan, K., Lustig, G., Bernstein, M., Archary, D., Cele, S., Karim, F., Smith, M., Ganga, Y., Jule, Z., Reedoy, K., Miya, Y., Mthabela, N., Magula, N. P., Lessells, R., de Oliveira, T., Gosnell, B. I., Karim, S. A., Garrett, N., Hanekom, W., Gail-Bekker, L., Gray, G., Blackburn, J. M., Moosa, M. S. & Sigal, A. Immunogenicity of SARS-CoV-2 infection and Ad26.CoV2.S vaccination in people living with HIV. Clin. Infect. Dis.
Karim, F., Gazy, I., Cele, S., Zungu, Y., Krause, R., Bernstein, M., Khan, K., Ganga, Y., Rodel, H., Mthabela, N., Mazibuko, M., Muema, D., Ramjit, D., Ndung’u, T., Hanekom, W., Gosnell, B., Lessells, R. J., Wong, E. B., de Oliveira, T., Moosa, M. S., Lustig, G., Leslie, A., Kløverpris, H. & Sigal, A. HIV status alters disease severity and immune cell responses in beta variant SARS-CoV-2 infection wave. eLife.
Lustig, G., Cele, S., Karim, F., Derache, A., Ngoepe, A., Khan, K., Gosnell, B. I., Moosa, M. S., Ntshuba, N., Marais, S., Jeena, P. M., Govender, K., Adamson, J., Kloverpris, H., Gupta, R. K., Harrichandparsad, R., Patel, V. B. & Sigal, A. T cell derived HIV-1 is present in the CSF in the face of suppressive antiretroviral therapy. PLoS Pathogens.
Rodel, H. E., Ferreira, I., Ziegler, C. G. K., Ganga, Y., Bernstein, M., Hwa, S. H., Nargan, K., Lustig, G., Kaplan, G., Noursadeghi, M., Shalek, A. K., Steyn, A. J. C. & Sigal, A. Aggregated Mycobacterium tuberculosis Enhances the Inflammatory Response. Frontiers.
Snyman, J., Hwa, S. H., Krause, R., Muema, D., Reddy, T., Ganga, Y., Karim, F., Leslie, A., Sigal, A. & Ndung’u, T. Similar antibody responses against SARS-CoV-2 in HIV uninfected and infected individuals on antiretroviral therapy during the first South African infection wave. Similar antibody responses against SARS-CoV-2 in HIV uninfected and infected individuals on antiretroviral therapy during the first South African infection wave. Clin. Infect. Dis.
Tegally, H., Wilkinson, E., Lessells, R. J., Giandhari, J., Pillay, S., Msomi, N., Mlisana, K., Bhiman, J. N., von Gottberg, A., Walaza, S., Fonseca, V., Allam, M., Ismail, A., Glass, A. J., Engelbrecht, S., Van Zyl, G., Preiser, W., Williamson, C., Petruccione, F., Sigal, A., Gazy, I., Hardie, D., Hsiao, N. Y., Martin, D., York, D., Goedhals, D., San, E. J., Giovanetti, M., Lourenco, J., Alcantara, L. C. J. & de Oliveira, T. Sixteen novel lineages of SARS-CoV-2 in South Africa. Nat Med.
Tegally, H., Wilkinson, E., Giovanetti, M., Iranzadeh, A., Fonseca, V., Giandhari, J., Doolabh, D., Pillay, S., San, E. J., Msomi, N., Mlisana, K., von Gottberg, A., Walaza, S., Allam, M., Ismail, A., Mohale, T., Glass, A. J., Engelbrecht, S., Van Zyl, G., Preiser, W., Petruccione, F., Sigal, A., Hardie, D., Marais, G., Hsiao, N. Y., Korsman, S., Davies, M. A., Tyers, L., Mudau, I., York, D., Maslo, C., Goedhals, D., Abrahams, S., Laguda-Akingba, O., Alisoltani-Dehkordi, A., Godzik, A., Wibmer, C. K., Sewell, B. T., Lourenço, J., Alcantara, L. C. J., Kosakovsky Pond, S. L., Weaver, S., Martin, D., Lessells, R. J., Bhiman, J. N., Williamson, C. & de Oliveira, T. Detection of a SARS-CoV-2 variant of concern in South Africa. Nature.
Madhi, S. A., Baillie, V., Cutland, C. L., Voysey, M., Koen, A. L., Fairlie, L., Padayachee, S. D., Dheda, K., Barnabas, S. L., Bhorat, Q. E., Briner, C., Kwatra, G., Ahmed, K., Aley, P., Bhikha, S., Bhiman, J. N., Bhorat, A. E., du Plessis, J., Esmail, A., Groenewald, M., Horne, E., Hwa, S. H., Jose, A., Lambe, T., Laubscher, M., Malahleha, M., Masenya, M., Masilela, M., McKenzie, S., Molapo, K., Moultrie, A., Oelofse, S., Patel, F., Pillay, S., Rhead, S., Rodel, H., Rossouw, L., Taoushanis, C., Tegally, H., Thombrayil, A., van Eck, S., Wibmer, C. K., Durham, N. M., Kelly, E. J., Villafana, T. L., Gilbert, S., Pollard, A. J., de Oliveira, T., Moore, P. L., Sigal, A. & Izu, A. Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. N Engl J Med.
Garcia-Beltran, W. F., Lam, E. C., St Denis, K., Nitido, A. D., Garcia, Z. H., Hauser, B. M., Feldman, J., Pavlovic, M. N., Gregory, D. J., Poznansky, M. C., Sigal, A., Schmidt, A. G., Iafrate, A. J., Naranbhai, V. & Balazs, A. B. Multiple SARS-CoV-2 variants escape neutralization by vaccine-induced humoral immunity. Cell.
Skelly, D. T., Harding, A. C., Gilbert-Jaramillo, J., Knight, M. L., Longet, S., Brown, A., Adele, S., Adland, E., Brown, H., Medawar Laboratory, T., Tipton, T., Stafford, L., Mentzer, A. J., Johnson, S. A., Amini, A., Group, O. C., Tan, T. K., Schimanski, L., Huang, K. A., Rijal, P., Group, P. S., Group, C. M. P.-C., Frater, J., Goulder, P., Conlon, C. P., Jeffery, K., Dold, C., Pollard, A. J., Sigal, A., de Oliveira, T., Townsend, A. R., Klenerman, P., Dunachie, S. J., Barnes, E., Carroll, M. W. & James, W. S. Two doses of SARS-CoV-2 vaccination induce robust immune responses to emerging SARS-CoV-2 variants of concern. Nature Communications.
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