diff --git a/EpiAware/src/EpiInfModels/ExpGrowthRate.jl b/EpiAware/src/EpiInfModels/ExpGrowthRate.jl
index 5b142db0f..ffb412b2f 100644
--- a/EpiAware/src/EpiInfModels/ExpGrowthRate.jl
+++ b/EpiAware/src/EpiInfModels/ExpGrowthRate.jl
@@ -116,5 +116,5 @@ I_t = generated_quantities(latent_inf, θ)
 "
 @model function EpiAwareBase.generate_latent_infs(epi_model::ExpGrowthRate, rt)
     init_incidence ~ epi_model.initialisation_prior
-    return xexpy.(1.0, accumulate(+, rt; init = init_incidence))
+    return xexpy.(1.0, init_incidence .+ cumsum(rt))
 end