Abstract:
In the absence of effective drugs, vaccines constitute the cornerstone for the prevention of
Newcastle disease (ND). Different strategies have been implemented to increase vaccina-
tion, but uptake remains low, underscoring the need for novel vaccine delivery methods. We
designed and assessed the effectiveness of a community-centered ND vaccine delivery
model in southeastern Kenya. Under the model, we sensitized smallholder chicken farmers
(SCFs) through structured training on chicken husbandry, biosecurity, ND, and its vaccina-
tion, among other aspects. We subsequently engaged trained community vaccinators (CVs)
to deliver vaccines and/or provide vaccination services to SCFs at a cost on one hand and,
at no cost on the other, in selected sites to address challenges of inadequate service provid-
ers, vaccine unavailability, and inaccessibility. We tested this model under paid and free
vaccination frameworks over one year and assessed the model’s effect on vaccine uptake,
ND-related deaths, and vaccine accessibility, among other aspects. Overall, we vaccinated
more chickens at free sites compared to paid sites. However, we vaccinated a significantly
higher mean number of chickens per household at paid (49.4±38.5) compared to free (28.4
±25.9) sites (t = 8.4, p<0.0001). We recorded a significant increase in the proportion of
SCFs who vaccinated their chickens from 31.3% to 68.4% (χ2(1, N = 399) = 58.3, p<0.0001) in
paid and from 19.9% to 74.9% (χ2(1, N = 403) = 115.7, p<0.0001) in free sites pre- and post-
intervention, respectively. The mean number of ND-related deaths reported per household
decreased from 18.1±31.6 pre-intervention to 7.5±22.3 post-intervention (t = 5.4, p = 0.000),
with higher reductions recorded in paid sites (20.9±37.7 to 4.5±11.2) compared to free sites
(15.0±22.6 to 10.7±29.7) pre- and post-intervention, respectively. Farmers with access to
vaccines increased significantly from 61.1% to 85.4% (χ2(1, N = 399) = 31.7, p<0.0001) in paid
and 43.6% to 74.9% (χ2(1, N = 403) = 38.4, p = 0.0001) in free sites pre- and post-intervention,
respectively. We established that type of intervention framework, gender of household
head, if the household head attended training on chicken production in the last 12 months, access to information on ND vaccination, and the number of chickens lost to the previous
ND outbreak were significant predictors of ND vaccine uptake. Our findings indicate the
model has a broader reach and benefits for SCFs. However, policies should be enacted to
regulate the integration of CVs into the formal animal health sector.