EVALUATION OF CHITOSAN NANOPARTICLES (CSNP) AS POTENT IMMUNE ADJUVANT FOR PESTE DES PETITS RUMINANTS (PPR) LIVE OCULAR VACCINE: A STEP FORWARD TOWARDS ERADICATION Authors: Shafeeq Ur Rehman, Waqas Ashraf, Muhammad Salahuddin Shah, Muhammad Moazam Jalees, Muhammad Shan Journal: Journal of Animal and Plant Sciences (JAPS) ISSN: 1018-7081 (Print), 2309-8694 (Online) Volume: 36 Issue: 5 Year: 2026 DOI: https://doi.org/10.36899/JAPS.2026.5.0120 URL: https://doi.org/https://doi.org/10.36899/JAPS.2026.5.0120 Publisher: Pakistan Agricultural Scientists Forum Abstract:

Peste des Petits Ruminants (PPR) is a highly contagious viral disease of small ruminants that causes significant economic losses and threatens global food security. Although the Nigeria 75/1 PPR vaccine is effective, improved immunization strategies are needed to induce mucosal immunity with an inherent potential to reduce virus shedding and transmission. This study evaluated the immune response induced by a Chitosan Nanoparticle (CSNP)-based PPR vaccine administered through intranasal (IN) and ocular (OC) routes in goats. Methods: CSNPs were synthesized using the ionic gelation method, confirmed sterile, and mixed with the Nigeria 75/1 PPR vaccine in equal proportions. Five groups were designed: G1 and G2 received the standard vaccine via IN and OC routes; G3 and G4 received the CSNP-based vaccine via the same routes; G5 served as the unvaccinated control. Immune response was assessed using white blood cell (WBC) counts, competitive ELISA (c-ELISA), and Virus Neutralization Test (VNT). Results: G3 and G4 demonstrated enhanced, persistent antibody responses and significantly higher WBC counts than other groups. At day 60 post-vaccination, c-ELISA values were highest in G3 (91.7) and G4 (91.6), while VNT results showed virus neutralization up to a 1:640 dilution for CSNP-based vaccines, compared with 1:80 for the standard vaccine. The control group remained negative throughout. These findings indicate that the CSNP-based PPR vaccine, particularly via the ocular route, enhances both humoral and mucosal immunity. This formulation represents a promising, sustainable approach for efficient vaccination and supports global efforts toward PPR eradication by 2030.

Keywords: PPR eradication, Mucosal vaccination, Immune adjuvant, Nanoparticle-based vaccine, CSNP-based PPR vaccine