Overall, filibustering and U.S. policies seem to have hindered more than helped U.S. attempts at territorial expansion in this time period. The Gadsden Purchase was the only official territorial acquisition during the 1850s.
Acellular pertussis vaccines were introduced nation-wide in Sweden in 1996, 17 years after the withdrawal of whole-cell pertussis vaccine from the childhood immunisation schedule.he annual incidence of culture-confirmed B. pertussis was 89-150 per 100,000 before introduction of acellular pertussis vaccines and has dropped to 17-26 per 100,000. The data suggest that unimmunised infants and children who have received only one dose of pertussis vaccine were provided some protection.
DTaP and Tdap refer to similar combination vaccines in which the component with lower case a is acellular. Also available is the DT or TD vaccine, which lacks the pertussis component. The Tdap vaccine is currently recommended by the CDC and covers tetanus, diphtheria and pertussis (CDC Vaccines, 2013). In the United Kingdom, the Netherlands and France, the abbreviation DTP refers to a combination vaccine against diphtheria, tetanus, and poliomyelitis.