- Biển số
- OF-343585
- Ngày cấp bằng
- 20/11/14
- Số km
- 253
- Động cơ
- 274,170 Mã lực
Whole-Cell Pertussis Vaccines
Four diphtheria and tetanus toxoids combined with whole-cell pertussis (DTP) vaccines are presently licensed for use in the United States.@ Vaccines of this type, prepared from suspensions of inactivated Bordetella pertussis bacterial cells, have been licensed for routine vaccination of infants since the mid-1940s. Based on controlled efficacy trials conducted in the 1940s and on subsequent observational efficacy studies, a primary series comprising four doses of whole-cell DTP vaccine is considered 70%-90% effective in preventing serious pertussis disease (1-4).
Whole-cell DTP vaccines are commonly associated with several local adverse events (e.g., erythema, swelling, and pain at the injection site), fever, and other mild systemic events (e.g., drowsiness, fretfulness, and anorexia) (5,6). More severe systemic events (e.g., convulsions {with or without fever} and hypotonic hyporesponsive episodes) occur less frequently (ratio of one case to 1,750 doses administered) among children who receive whole-cell DTP vaccine (5). Acute encephalopathy occurs even more rarely (ratio of 0-10.5 cases to one million doses administered) (7). Experts disagree on whether whole-cell pertussis vaccine causes lasting brain damage, but agree that if the vaccine causes such damage it does so only rarely (7). Concerns about safety prompted the development of more purified (acellular) pertussis vaccines that are associated with a lower frequency of adverse events and are effective in preventing pertussis disease.
Acellular Pertussis Vaccines
Acellular pertussis vaccines contain inactivated pertussis toxin (PT) and may contain one or more other bacterial components (e.g., filamentous hemagglutinin {FHA}, a 69-kilodalton outer-membrane protein -- pertactin {Pn}, and fimbriae {Fim} types 2 and 3). PT is detoxified either by treatment with a chemical (e.g., hydrogen peroxide, formalin and/or glutaraldehyde) or by using molecular genetic techniques. Acellular pertussis vaccines contain substantially less endotoxin than whole-cell pertussis vaccines.
Since 1991, two acellular pertussis vaccines (Tripedia{Registered} and ACEL-IMUNE{Registered}) have been licensed for use in the United States. Until recently, both vaccines were licensed for use only as the fourth and fifth doses of the diphtheria, tetanus, and pertussis vaccination series among children aged 15 months-6 years who had received three primary doses of whole-cell DTP (16,17). This licensure was based on findings of studies conducted in Sweden and Japan. These studies did not evaluate the efficacy of acellular pertussis vaccines administered to infants on a schedule similar to the one used in the United States and did not directly compare the efficacy of DTaP vaccines with that of whole-cell DTP vaccines (18-22).
http://www.cdc.gov/mmwr/preview/mmwrhtml/00048610.htm
Đậm 1: Những lo ngại về độ an toàn [của vắc xin ho gà toàn tế bào] đã thúc đẩy việc phát triển vắc xin ho gà (vô bào) tinh khiết hơn.
Đậm 2: Vắc xin ho gà vô bào chứa ít nội độc tố hơn rõ rệt so với vắc xin ho gà toàn tế bào
Quin chứa vắc xin ho gà toàn tế bào. Vắc xin dịch vụ (Pentaxim, Heparix) chứa vắc xin ho gà vô bào
Four diphtheria and tetanus toxoids combined with whole-cell pertussis (DTP) vaccines are presently licensed for use in the United States.@ Vaccines of this type, prepared from suspensions of inactivated Bordetella pertussis bacterial cells, have been licensed for routine vaccination of infants since the mid-1940s. Based on controlled efficacy trials conducted in the 1940s and on subsequent observational efficacy studies, a primary series comprising four doses of whole-cell DTP vaccine is considered 70%-90% effective in preventing serious pertussis disease (1-4).
Whole-cell DTP vaccines are commonly associated with several local adverse events (e.g., erythema, swelling, and pain at the injection site), fever, and other mild systemic events (e.g., drowsiness, fretfulness, and anorexia) (5,6). More severe systemic events (e.g., convulsions {with or without fever} and hypotonic hyporesponsive episodes) occur less frequently (ratio of one case to 1,750 doses administered) among children who receive whole-cell DTP vaccine (5). Acute encephalopathy occurs even more rarely (ratio of 0-10.5 cases to one million doses administered) (7). Experts disagree on whether whole-cell pertussis vaccine causes lasting brain damage, but agree that if the vaccine causes such damage it does so only rarely (7). Concerns about safety prompted the development of more purified (acellular) pertussis vaccines that are associated with a lower frequency of adverse events and are effective in preventing pertussis disease.
Acellular Pertussis Vaccines
Acellular pertussis vaccines contain inactivated pertussis toxin (PT) and may contain one or more other bacterial components (e.g., filamentous hemagglutinin {FHA}, a 69-kilodalton outer-membrane protein -- pertactin {Pn}, and fimbriae {Fim} types 2 and 3). PT is detoxified either by treatment with a chemical (e.g., hydrogen peroxide, formalin and/or glutaraldehyde) or by using molecular genetic techniques. Acellular pertussis vaccines contain substantially less endotoxin than whole-cell pertussis vaccines.
Since 1991, two acellular pertussis vaccines (Tripedia{Registered} and ACEL-IMUNE{Registered}) have been licensed for use in the United States. Until recently, both vaccines were licensed for use only as the fourth and fifth doses of the diphtheria, tetanus, and pertussis vaccination series among children aged 15 months-6 years who had received three primary doses of whole-cell DTP (16,17). This licensure was based on findings of studies conducted in Sweden and Japan. These studies did not evaluate the efficacy of acellular pertussis vaccines administered to infants on a schedule similar to the one used in the United States and did not directly compare the efficacy of DTaP vaccines with that of whole-cell DTP vaccines (18-22).
http://www.cdc.gov/mmwr/preview/mmwrhtml/00048610.htm
Đậm 1: Những lo ngại về độ an toàn [của vắc xin ho gà toàn tế bào] đã thúc đẩy việc phát triển vắc xin ho gà (vô bào) tinh khiết hơn.
Đậm 2: Vắc xin ho gà vô bào chứa ít nội độc tố hơn rõ rệt so với vắc xin ho gà toàn tế bào
Quin chứa vắc xin ho gà toàn tế bào. Vắc xin dịch vụ (Pentaxim, Heparix) chứa vắc xin ho gà vô bào