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Using Reverse Genetics to Manipulate the NSs Gene of the Rift Valley Fever Virus MP-12 Strain to Improve Vaccine Safety and Efficacy
Published on: November 1, 2011
The 40Fp8 vaccine strain is safe and protects pregnant ewes from a virulent RVFV challenge
Belén Borrego1, Celia Alonso1, Sandra Moreno1
1Centro de Investigación en Sanidad Animal (CISA-INIA-CSIC). Valdeolmos, 28130, Madrid, Spain.
Abstract:
In the present study, we evaluated the immunogenicity, safety and protective efficacy of the attenuated RVFV-40Fp8 strain in natural hosts (non-pregnant ewes) and in a highly susceptible host infection model such as pregnant ewes in the first third of pregnancy. Our results confirm the immunogenicity of 40Fp8 administration in non-pregnant and pregnant ewes, as well as the absence of foetal damage even after a high-dose vaccination regime in pregnant ewes. In addition, the ewes and their foetuses were protected against a virulent RVFV-56/74 strain challenge, as shown by comparative evaluation of blood, serum and different tissue samples from vaccinated and non-vaccinated pregnant ewes. These results confirm the potential use of 40Fp8 as a RVF live-attenuated vaccine candidate and pave the way for further clinical developments.
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