BACKGROUND: In 1999, meningococcal serogroup C conjugate (MCC) vaccines were introduced in the United Kingdom for those under 19 years of age. The impact of this intervention on asymptomatic carriage of meningococci was investigated to establish whether serogroup replacement or protection by herd immunity occurred. METHODS: Multicenter surveys of carriage were conducted during vaccine introduction and on 2 successive years, resulting in a total of 48,309 samples, from which 8599 meningococci were isolated and characterized by genotyping and phenotyping. RESULTS: A reduction in serogroup C carriage (rate ratio, 0.19) was observed that lasted at least 2 years with no evidence of serogroup replacement. Vaccine efficacy against carriage was 75\%, and vaccination had a disproportionate impact on the carriage of sequence type (ST)-11 complex serogroup C meningococci that (rate ratio, 0.06); these meningococci also exhibited high rates of capsule expression. CONCLUSIONS: The impact of vaccination with MCC vaccine on the prevalence of carriage of group C meningococci was consistent with herd immunity. The high impact on the carriage of ST-11 complex serogroup C could be attributed to high levels of capsule expression. High vaccine efficacy against disease in young children, who were not protected long-term by the schedule initially used, is attributed to the high vaccine efficacy against carriage in older age groups.
%0 Journal Article
%1 maiden_impact_2008
%A Maiden, Martin C J
%A Ibarz-Pavón, Ana Belén
%A Urwin, Rachel
%A Gray, Stephen J
%A Andrews, Nicholas J
%A Clarke, Stuart C
%A Walker, A Mark
%A Evans, Meirion R
%A Kroll, J Simon
%A Neal, Keith R
%A Ala'aldeen, Dlawer A A
%A Crook, Derrick W
%A Cann, Kathryn
%A Harrison, Sarah
%A Cunningham, Richard
%A Baxter, David
%A Kaczmarski, Edward
%A Maclennan, Jenny
%A Cameron, J Claire
%A Stuart, James M
%D 2008
%J The Journal of Infectious Diseases
%K Adolescent, Adult, Britain, C, Carrier Great Herd, Humans, Immunity, Immunization, Infections, Mass Meningococcal Neisseria Serogroup Serotyping State, Studies, Vaccines, meningitidis, {Cross-Sectional}
%N 5
%P 737--43
%R 10.1086/527401
%T Impact of meningococcal serogroup C conjugate vaccines on carriage and herd immunity
%V 197
%X BACKGROUND: In 1999, meningococcal serogroup C conjugate (MCC) vaccines were introduced in the United Kingdom for those under 19 years of age. The impact of this intervention on asymptomatic carriage of meningococci was investigated to establish whether serogroup replacement or protection by herd immunity occurred. METHODS: Multicenter surveys of carriage were conducted during vaccine introduction and on 2 successive years, resulting in a total of 48,309 samples, from which 8599 meningococci were isolated and characterized by genotyping and phenotyping. RESULTS: A reduction in serogroup C carriage (rate ratio, 0.19) was observed that lasted at least 2 years with no evidence of serogroup replacement. Vaccine efficacy against carriage was 75\%, and vaccination had a disproportionate impact on the carriage of sequence type (ST)-11 complex serogroup C meningococci that (rate ratio, 0.06); these meningococci also exhibited high rates of capsule expression. CONCLUSIONS: The impact of vaccination with MCC vaccine on the prevalence of carriage of group C meningococci was consistent with herd immunity. The high impact on the carriage of ST-11 complex serogroup C could be attributed to high levels of capsule expression. High vaccine efficacy against disease in young children, who were not protected long-term by the schedule initially used, is attributed to the high vaccine efficacy against carriage in older age groups.
@article{maiden_impact_2008,
abstract = {{BACKGROUND:} In 1999, meningococcal serogroup C conjugate {(MCC)} vaccines were introduced in the United Kingdom for those under 19 years of age. The impact of this intervention on asymptomatic carriage of meningococci was investigated to establish whether serogroup replacement or protection by herd immunity occurred. {METHODS:} Multicenter surveys of carriage were conducted during vaccine introduction and on 2 successive years, resulting in a total of 48,309 samples, from which 8599 meningococci were isolated and characterized by genotyping and phenotyping. {RESULTS:} A reduction in serogroup C carriage (rate ratio, 0.19) was observed that lasted at least 2 years with no evidence of serogroup replacement. Vaccine efficacy against carriage was 75\%, and vaccination had a disproportionate impact on the carriage of sequence type {(ST)-11} complex serogroup C meningococci that (rate ratio, 0.06); these meningococci also exhibited high rates of capsule expression. {CONCLUSIONS:} The impact of vaccination with {MCC} vaccine on the prevalence of carriage of group C meningococci was consistent with herd immunity. The high impact on the carriage of {ST-11} complex serogroup C could be attributed to high levels of capsule expression. High vaccine efficacy against disease in young children, who were not protected long-term by the schedule initially used, is attributed to the high vaccine efficacy against carriage in older age groups.},
added-at = {2011-03-11T10:05:34.000+0100},
author = {Maiden, Martin C J and {Ibarz-Pavón}, Ana Belén and Urwin, Rachel and Gray, Stephen J and Andrews, Nicholas J and Clarke, Stuart C and Walker, A Mark and Evans, Meirion R and Kroll, J Simon and Neal, Keith R and Ala'aldeen, Dlawer A A and Crook, Derrick W and Cann, Kathryn and Harrison, Sarah and Cunningham, Richard and Baxter, David and Kaczmarski, Edward and Maclennan, Jenny and Cameron, J Claire and Stuart, James M},
biburl = {https://www.bibsonomy.org/bibtex/2b8728410d0e5a41dabcb2fbbb1c14764/jelias},
doi = {10.1086/527401},
interhash = {fd2945793a38d9e9ac4cef339728c6b1},
intrahash = {b8728410d0e5a41dabcb2fbbb1c14764},
issn = {0022-1899},
journal = {The Journal of Infectious Diseases},
keywords = {Adolescent, Adult, Britain, C, Carrier Great Herd, Humans, Immunity, Immunization, Infections, Mass Meningococcal Neisseria Serogroup Serotyping State, Studies, Vaccines, meningitidis, {Cross-Sectional}},
month = mar,
note = {{PMID:} 18271745},
number = 5,
pages = {737--43},
timestamp = {2011-03-11T10:06:34.000+0100},
title = {Impact of meningococcal serogroup C conjugate vaccines on carriage and herd immunity},
volume = 197,
year = 2008
}