Invasive Haemophilus influenzae type b infections in vaccinated and unvaccinated children in Canada, 2001-2003
| Autor: | David, Scheifele, Scott, Halperin, Barbara, Law, Arlene, King, Robert, Morris, Charles A, Janeway, Pierre, Déry, Marc, Lebel, Dorothy, Moore, Nicole, Le Saux, Elizabeth, Ford-Jones, Ben, Tan, Taj, Jadavji, Wendy, Vaudry, Wikke, Walop, Joanne, Embree, John, Waters |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Male
Canada Pediatrics medicine.medical_specialty Haemophilus Infections Haemophilus influenzae type Primary vaccination Disease Tertiary care Humans Medicine Child Meningitis Haemophilus Haemophilus Vaccines business.industry Research Haemophilus influenzae type b Infant General Medicine Hepatitis B Hospitals Pediatric medicine.disease Vaccination Parental refusal Child Preschool Population Surveillance business Meningitis |
| Zdroj: | Canadian Medical Association Journal. 172:53-56 |
| ISSN: | 1488-2329 0820-3946 |
| DOI: | 10.1503/cmaj.1031861 |
| Popis: | Background: Although vaccination of infants against Haemophilus influenzae type b (Hib) invasive infections is effective and has been routinely available in Canada since 1992, cases of the disease continue to occur. We were interested in determining whether recent cases of Hib infection reflected progressive loss of protection with time since vaccination, increasing nonacceptance of vaccination or a deleterious effect of coadministration of recently introduced vaccines such as those for pneumococcal and meningococcal conjugates and hepatitis B. We report on the causes of Hib infections among vaccinated and unvaccinated children between 2001 and 2003 in Canada. Methods: Through our established network of 12 pediatric tertiary care hospitals we actively searched for cases in each centre by reviewing daily admissions and laboratory reports, visiting the wards and checking discharge diagnosis codes. Culture-confirmed cases were summarized by nurse monitors using a standardized reporting system. Results: We identified 29 cases during the 3 years: 16 in 2001, 10 in 2002 and 3 in 2003. Half of the 29 patients had meningitis. Hib infection was more common among children less than 6 months of age (11 cases) and in boys (20 cases). Two deaths occurred (7% case-fatality ratio). A total of 20 children had received no or incomplete primary vaccination because of parental refusal (7 cases), because they were too young to have completed the primary series (11 cases, including 1 in which parental refusal was also a factor) or because of delays in completing the primary series (2 cases); the vaccination history was uncertain in the remaining case. Infection despite primary vaccination occurred in 9 children: 2 previously healthy children and 7 who were immunocompromised or who had a predisposing condition. None of the cases identified in 2003 involved children who had received any of the newly introduced vaccines. Interpretation: Invasive Hib infections remain rare in Canada, with most cases occurring in children too young to have completed the primary series. Protection after vaccination appears to extend into later childhood and does not appear to be diminished by coadministration of newer infant vaccines. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|