The viral replication cycle is crucial for a virus to spread inside the body and cause disease. Focusing on that cycle in the hepatitis A virus (HAV), UNC School of Medicine scientists discovered that replication requires specific interactions between the human protein ZCCHC14 and a group of enzymes called TENT4 poly(A) polymerases. They also found that the oral compound RG7834 stopped replication at a key step, making it impossible for the virus to infect liver cells.