Carriage of Haemophilus influenzae type b in children after widespread vaccination with conjugate Haemophilus influenzae type b vaccines

Increase in Genetic Diversity of Haemophilus influenzae Serotype b (Hib) Strains after Introduction of Hib Vaccination in The Netherlands

“…Possibly, an increase of Hib disease in adults may have been caused by an increased circulation of Hib within this age group. Several studies have reported an impressive decrease in Hib carriage among children after the introduction of the Hib vaccine (1,19,27,28). Although there is no published experimental data to support this, it seems safe to presume that a similar decrease in carriage occurred after the introduction of the Hib vaccine in The Netherlands.…”

Worldwide Haemophilus influenzae Type b Disease at the Beginning of the 21st Century: Global Analysis of the Disease Burden 25 Years after the Use of the Polysaccharide Vaccine and a Decade after the Advent of Conjugates

“…Few vaccines in history have induced such a dramatic decline in incidence over such a short period as have the Hib conjugates. The ability of these vaccines to prevent nasopharyngeal Hib colonization under most (86,112,113,116,163,166) Table 4). …”

Haemophilus influenzae type b conjugate vaccines – A South African perspective

“…In addition, the vaccine offered indirect protection by delaying nasopharyngeal carriage and asymptomatic colonization amongst vaccinated infants [54][55][56][57]. This provides an additional level of herd immunity [58,59]. For this reason, Hib vaccine is considered to have effectiveness greater than reported efficacy [6].…”