Two combination vaccines are also available for use in children: Comvax (Merck), a combined hepatitis B and Haemophilus influenzae type b (Hib) conjugate vaccine, and Pediarix (GlaxoSmithKline), a combined hepatitis B, diphtheria, tetanus, acellular pertussis (DTaP), and inactivated poliovirus (IPV) vaccine. Here, PPIB is linked to hepatitis A virus infection.