Dataset Information

Carriage of Haemophilus influenzae serotype A in children: Canadian Immunization Research Network (CIRN) study.

ABSTRACT:

Background

Haemophilus influenzae serotype a (Hia) has recently emerged as an important cause of invasive disease, mainly affecting young Indigenous children. Carriage of H. influenzae is a pre-requisite for invasive disease and reservoir for transmission. To better understand the epidemiology of invasive Hia disease, we initiated a multicentre study of H. influenzae nasopharyngeal carriage among Canadian children.

Methods

With prior parental consent, we collected nasotracheal tubes used during general anaesthesia in healthy children following routine dental surgery in a regional hospital of northwestern Ontario and a dental clinic in central Saskatchewan. In northwestern Ontario, all children were Indigenous (median age 48.0 months, 45.8% female); in Saskatchewan, children were from various ethnic groups (62% Indigenous, median age 56.3 months, 43.4% female). Detection of H. influenzae and serotyping were performed using molecular-genetic methods.

Results

A total of 438 nasopharyngeal specimens, 286 in northwestern Ontario and 152 in Saskatchewan were analyzed. Hia was identified in 26 (9.1%) and 8 (5.3%) specimens, respectively. In Saskatchewan, seven out of eight children with Hia carriage were Indigenous.

Conclusions

The carriage rates of Hia in healthy children in northwestern Ontario and Saskatchewan are comparable to H. influenzae serotype b (Hib) carriage among Alaska Indigenous children in the pre-Hib-vaccine era. To prevent invasive Hia disease, paediatric conjugate Hia vaccines under development have the potential to reduce carriage of Hia, and thus decrease the risk of transmission and disease among susceptible populations. Addressing the social determinants of health may further eliminate conditions favouring Hia transmission in Indigenous communities.

SUBMITTER: Ulanova M

PROVIDER: S-EPMC10984318 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Publications

Carriage of <i>Haemophilus influenzae</i> serotype A in children: Canadian Immunization Research Network (CIRN) study.

Ulanova Marina M Tsang Raymond Sw RS Nix Eli B EB Tan Ben B Huska Brenda B Kelly Len L Shuel Michelle M Allarie Julina J

Journal of the Association of Medical Microbiology and Infectious Disease Canada = Journal officiel de l'Association pour la microbiologie medicale et l'infectiologie Canada 20240329 1

<h4>Background</h4><i>Haemophilus influenzae</i> serotype a (Hia) has recently emerged as an important cause of invasive disease, mainly affecting young Indigenous children. Carriage of <i>H. influenzae</i> is a pre-requisite for invasive disease and reservoir for transmission. To better understand the epidemiology of invasive Hia disease, we initiated a multicentre study of <i>H. influenzae</i> nasopharyngeal carriage among Canadian children.<h4>Methods</h4>With prior parental consent, we colle ...[more]

PMID: 38567364

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