Quantifying the delay in eliminating vaccine-targeted human papillomavirus after a drop in the coverage using a lifetime sexual partners network

Vaccination programs should be resilient to maintain high effectiveness despite challenges that could negatively impact coverage rates. These challenges may include adverse campaigns, vaccine hesitancy, or a pandemic such as the recent COVID-19 pandemic. Human Papillomavirus (HPV) vaccination programs have faced several of these challenges over the last years. In this work, we have used an agent-based model defined as a network of sexual contacts where the nodes represent individuals who can transmit oncogenic HPV genotypes through the links and paths defined by the sexual partners, drawing the dynamics of the disease transmission. Heterosexuals and men who have sex with men (MSM) contacts are considered. In this context, we have defined several scenarios: a only girls’ vaccination program (OGV), vaccination to girls and boys, usually called gender-neutral vaccination (GNV), an OGV program with a sharp drop in coverage as happened in Denmark in 2014, and a GNV program with the same coverage drop. For girls aged 14–21, the drop in vaccination coverage meant that, on average, protection against HPV oncogenic infections was reduced by 49.54% for OGV, while for GNV, it was only reduced by 30.64%. For boys aged 14–21, the drop in vaccination coverage meant that, on average, protection against HPV oncogenic infections was reduced by 68.38% for OGV, while for GNV, it was only reduced by 33.07%. The time needed to recover pre-drop protection levels is 9.7 years on average in boys in GNV versus 15.8 years for OGV and 11.7 years on average in girls in GNV versus 20.1 for OGV. Our simulations show that a GNV program is much more resilient to the drop in coverage for any cause versus an OGV program. • An LSP network to model HPV using Spanish data is constructed. • Oncogenic and non-oncogenic HPV transmission dynamics on the LSP network is described. • Vaccination campaign resilience against temporary drops in coverage is studied. • We conclude that gender-neutral vaccination is more resilient to the coverage drop.