Coxsackievirus A 16 infection does not interfere with the specific immune response induced by an enterovirus 71 inactivated vaccine in rhesus monkeys

Hand, foot and mouth disease is usually caused by enterovirus 71 (EV71) and coxsackievirus A 16 (CA16), which are members of the Picornaviridae family. In the present study, the characteristics of the immune response induced by an EV71 inactivated vaccine (made from human diploid cells) were explored in the presence of CA16 infection, based on the previously established neonatal rhesus monkey model. The typical clinical manifestations, including body temperature, viral viremia and virus shedding in the mouth, pharynx and feces, were characterized. A specific neutralizing antibody assay showed that the specific immune response induced by the EV71 inactivated vaccine was active against EV71 but not against CA16. No remarkable fluctuation in proinflammatory cytokine release was identified in the serum of immunized monkeys with EV71 vaccine and CA16 infections subsequently. The results showed that the specific immune response induced by the EV71 inactivated vaccine is effective against EV71 infection but is not affected by CA16 infection.