Pertussis vaccine is a vaccine that protects against whooping cough (pertussis). Pertussis is caused by the bacterium "Bordetella pertussis". DTaP protects against diphtheria, pertussis, and tetanus. Pediarix is a vaccine against diphtheria, tetanus, pertussis, hepatitis B, and poliomyelitis. DTaP and Tdap are both combined vaccines against diphtheria, tetanus, and pertussis. It is part of the diphtheria, tetanus, and acellular pertussis (DTaP) immunization. Child mortality was high and diphtheria and pertussis common. The acellular vaccine uses selected antigens of the pertussis pathogen to induce immunity. Regular vaccination against pneumonia, influenza, and pertussis are generally advised. Prevention is mainly by vaccination with the pertussis vaccine. Contraindication to Pertussis immunization should be observed in patients with encephalitis. Ushuaia suffered several epidemics, including typhus, pertussis, and measles, that much reduced the native population. The primary method of prevention for pertussis is vaccination. One study suggested that the availability of vaccine exemptions increases the number of pertussis cases. The production of pertussis vaccines started in 1948.