Bioscience

Bio

George is the Deputy Director at the Programme. He is a trained veterinary surgeon from the University of Nairobi, Kenya and completed his PhD in the epidemiology of childhood malaria in 2010. He later joined the Jenner Institute where, with support from Wellcome and other funders, he initiated a One Health vaccine programme in which vaccines against Rift Valley Fever and other zoonotic disease indications are co-developed for deployment in humans and the respective animal hosts of infection. Using this approach, he has developed a novel chimpanzee adenovirus vectored Rift Valley Fever vaccine that is highly efficacious in multiple target livestock species. The vaccine is just about to enter human phase I clinical trials in the UK and East Africa and will be evaluated in parallel livestock field trials in Kenya. He also co-led a similar One Health vaccine project for Middle East Respiratory Syndrome (MERS) aimed at developing a MERS vaccine for deployment in camels and humans.

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Current Work

Group research description: We work on viral infections that are transmitted between humans and animals in Africa with a focus on vaccine development for their control. While many of these viruses were first discovered in Africa, very little is known regarding their distribution, associated disease burden and viral genetic diversity in the continent. We are leveraging our unique biobank, spanning more than 30 years, at the Programme in coastal Kenya to address these knowledge gaps. We expect data from these studies to inform target product profiles for candidate vaccines and underpin the design of clinical trials for vaccine efficacy estimation. Our vaccine programmes exploit synergies in human and livestock immunology to accelerate development of candidate vaccines for deployment in humans and the respective animal hosts of infection. Using this approach, we have developed ChAdOx1 RVF, a novel chimpanzee adenovirus vectored Rift Valley Fever vaccine, that is highly efficacious in multiple target livestock species (sheep, goats, cattle) and is currently in human phase I clinical trials (NCT04754776, NCT04672824). We have worked on a similar One Health vaccine for use against Middle East Respiratory Syndrome (MERS) in camels and humans, and our veterinary research programmes continue to inform advances in human vaccinology. We are at forefront of addressing the global shortage in Yellow Fever (YF) vaccine supply through conduct of multicentre clinical trials to evaluate the utility of fractional vaccine dosing for epidemic control. Findings from this work could have a major impact on the number of doses that can be given based on the current global stock of YF vaccine and the number of doses that are produced for future use. Our recent work on COVID-19 serology in Kenya has informed decisions on the national pandemic response and remains one of the most comprehensive COVID-19 seroepidemiological programmes in Africa to date.

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Recent publications

Profile: The Kenya Multi-Site Serosurveillance (KEMIS) collaboration.
Kagucia, E. W., Voller, S., Ziraba, A. K., Bigogo, G., Munywoki, P. K., Makobu, K., Nokes, D. J., Nyagwange, J., Orlendo, C., Akech, D., Sigilai, A., Onyango, C., Juma, B., Herman-Roloff, A., Munyua, P., Apondi, C., Lidechi, S., Audi, A., Ouma, A., Aol, G., Misore, T., Nasimiyu, C., Onyango, D., Lo, T., Kasera, K., Jalang'o, R., Kingwara, L., Adetifa, I., Etyang, A. O., Warimwe, G., Agweyu, A., Scott, J. A. G.
Gates Open Res, (2024). 8:60

Low-Dose Yellow Fever Vaccine in Adults in Africa.
Kimathi, D., Juan-Giner, A., Bob, N. S., Orindi, B., Namulwana, M. L., Diatta, A., Cheruiyot, S., Fall, G., Dia, M., Hamaluba, M. M., Nyehangane, D., Karanja, H. K., Gitonga, J. N., Mugo, D., Omuoyo, D. O., Hussein, M., Oloo, E., Kamau, N., Wafula, J., Bendera, J., Silvester, N., Mwavita, J., Joshua, M., Mwendwa, J., Agababyona, C., Ngetsa, C., Aisha, N., Moki, F., Buluku, T., Munene, M., Mwanga-Amumpaire, J., Lutwama, J., Kayiwa, J., Kamaara, E., Barrett, A. D., Kaleebu, P., Bejon, P., Sall, A. A., Grais, R. F., Warimwe, G. M.
N Engl J Med, (2025). 392:788-797

Evaluation of population immunity against SARS-CoV-2 variants, EG.5.1, FY.4, BA.2.86, JN.1, JN.1.4, and KP.3.1.1 using samples from two health demographic surveillance systems in Kenya.
Lugano, D., Kutima, B., Kimani, M., Sigilai, A., Gitonga, J., Karani, A., Akech, D., Karia, B., Ziraba, A. K., Maina, A., Lambisia, A., Omuoyo, D., Mugo, D., Lucinde, R., Owuor, S., Konyino, G., Newman, J., Bailey, D., Nduati, E., Githinji, G., Agoti, C. N., Bejon, P., Scott, J. A. G., Agweyu, A., Kagucia, W., Warimwe, G. M., Sande, C., Ochola-Oyier, L. I., Nyagwange, J.
BMC Infect Dis, (2024). 24:1474

Profile: The Kenya Multi-Site Serosurveillance (KEMIS) collaboration .
Kagucia, E. W., Voller, S., Ziraba, A. K., Bigogo, G., Munywoki, P. K., Makobu, K., Nokes, D. J., Nyagwange, J., Orlendo, C., Akech, D., Sigilai, A., Onyango, C., Juma, B., Herman-Roloff, A., Munyua, P., Apondi, C., Lidechi, S., Audi, A., Ouma, A., Aol, G., Misore, T., Nasimiyu, C., Onyango, D., Lo, T., Kasera, K., Jalang'o, R., Kingwara, L., Adetifa, I., Etyang, A. O., Warimwe, G., Agweyu, A., Scott, J. A. G.
Gates Open Res, (2024). 8:

Kinetics of naturally induced binding and neutralising anti-SARS-CoV-2 antibody levels and potencies among SARS-CoV-2 infected Kenyans with diverse grades of COVID-19 severity: an observational study.
Kimotho, J., Sein, Y., Sayed, S., Shah, R., Mwai, K., Saleh, M., Wanjiku, P., Mwacharo, J., Nyagwange, J., Karanja, H., Kutima, B., Gitonga, J. N., Mugo, D., Karanu, A., Moranga, L., Oluoch, V., Shah, J., Mutiso, J., Mburu, A., Nneka, Z., Betti, P., Mutinda, W. U., Issak Abdi, A., Bejon, P., Ochola-Oyier, L. I., Warimwe G. M., Nduati, E. W., Ndungu, F. M.
Wellcome Open Res, (2023). 8:350