🦟 One step closer to a Zika vaccine. New publication by KU Leuven

Prof. Dr. Kai Dallmeier and his team at KU Leuven have published in Nature Communications the preclinical results of YF-ZIK, a chimeric live-attenuated vaccine candidate built on the backbone of the yellow fever vaccine (YF17D), one of the most effective human vaccines ever developed.

📌 Why Zika still matters:

In adults, infection is often mild. But in pregnant women, it can be devastating — causing severe congenital defects including microcephaly in newborns. To this day, no vaccine has been approved.

🔬 What our results show:

✅ A single dose induces neutralizing antibodies by Day 7, already above established protection thresholds.

✅ After a booster, near-sterilizing immunity: zero detectable viral RNA following a high-dose experimental challenge in preclinical step-up model (using 10-100x the estimated natural mosquito dose).

✅ The transcriptomic profile of YF-ZIK closely mirrors that of YF17D in humans, pointing to broad, durable immunity.

✅Systems vaccinology analysis identifies TNFRSF17 as a predictive biomarker of antibody response, the same gene previously flagged for YF17D in humans.

Safety. Immunogenicity. Efficacy. These robust preclinical data pave the way towards future clinical evaluation of YF-ZIK.

📄 Published in Nature Communications (December 2025)

Ma J, Malengier-Devlies B, Verstrepen BE, Alpizar YA, Vercruysse T, Javarappa MPA, Sanchez-Felipe L, Koopman G, de Groot NG, Matthys P, Neyts J, Verschoor EJ, Coelmont L, Thibaut HJ, Van Weyenbergh J, Dallmeier K. Immunological and transcriptomic profile of chimeric live-attenuated Zika vaccine linked to protection in non-human primates. Nat Commun. 2025 Dec 13;16(1):11221. doi: 10.1038/s41467-025-66073-4. PMID: 41390746; PMCID: PMC12714709.

🔗 https://pmc.ncbi.nlm.nih.gov/articles/PMC12714709/