Laura J. Sauvé

Pandemic influenza in Canadian children: a summary of hospitalized pediatric cases.

A total of 324 pandemic H1N1 cases were reported to the Immunization Monitoring Program, Active from May 1, 2009 to August 31, 2009. As of August 31, 2009, case details were available for 73% (n=235) of these cases. The median age was 4.8 years and 69% of children were older than 2 years of age. In total, 95 (40%) of children were previously healthy. The proportion with an underlying health condition increased with age. Close to 50% of children received antiviral medication. Two children died from the infection. The pediatric risk groups affected and course of disease caused by pandemic H1N1 appear similar to seasonal influenza.

The impact of the meningococcal serogroup C conjugate vaccine in Canada between 2002 and 2012

BACKGROUND Before 2001, the incidence of invasive meningococcal disease (IMD) in Canada was 1.0 per 100 000 per year, with 40% of cases caused by serogroup C organisms. During 2001-2005 all provinces introduced the meningococcal serogroup C conjugate vaccine (MCCV) into their routine infant immunization schedule. METHODS Active, prospective, population-based surveillance of IMD in children and adults was conducted by the Canadian Immunization Monitoring Program, ACTive (IMPACT) during 2002-2012. Inclusion criteria were admission to hospital and identification of Neisseria meningitidis from a sterile site. Incidence was estimated using population census data from Statistics Canada. RESULTS Prior to MCCV introduction, serogroup C disease incidence was 0.07-0.25 per 100 000 per year depending on the province. Following vaccine introduction, serogroup C disease decreased to <0.05 per 100 000 per year, with a reduction of 14% per year (P = .0014). A decrease occurred in all provinces, despite differing schedules being implemented. The largest decrease of 83% (from 0.27 to 0.05 per 100 000 per year) occurred in the 15-24 year age group (P = .0100) who were not vaccinated in all provinces. There was no impact on the incidence of nonserogroup C disease over the same period (P = .9811). CONCLUSIONS MCCV dramatically reduced the incidence of serogroup C IMD in Canada through both direct and indirect effects. The observation that disease incidence decreased with different schedules suggests that the doses at 12 months (common to all provinces) and adolescence (7 of 8 provinces studied) were critical in achieving disease control.

The responses of Aboriginal Canadians to adjuvanted pandemic (H1N1) 2009 influenza vaccine

Background: Because many Aboriginal Canadians had severe cases of pandemic (H1N1) 2009 influenza, they were given priority access to vaccine. However, it was not known if the single recommended dose would adequately protect people at high risk, prompting our study to assess responses to the vaccine among Aboriginal Canadians. Methods: We enrolled First Nations and Métis adults aged 20–59 years in our prospective cohort study. Participants were given one 0.5-mL dose of ASO3-adjuvanted pandemic (H1N1) 2009 vaccine (Arepanrix, GlaxoSmithKline Canada). Blood samples were taken at baseline and 21–28 days after vaccination. Paired sera were tested for hemagglutination-inhibiting antibodies at a reference laboratory. To assess vaccine safety, we monitored the injection site symptoms of each participant for seven days. We also monitored patients for general symptoms within 7 days of vaccination and any use of the health care system for 21–28 days after vaccination. Results: We enrolled 138 participants in the study (95 First Nations, 43 Métis), 137 of whom provided all safety data and 136 of whom provided both blood samples. First Nations and Métis participants had similar characteristics, including high rates of chronic health conditions (74.4%–76.8%). Pre-existing antibody to the virus was detected in 34.3% of the participants, all of whom boosted strongly with vaccination (seroprotection rate [titre ≥ 40] 100%, geometric mean titre 531–667). Particpants with no pre-existing antibody also responded well. Fifty-eight of 59 (98.3%) First Nations participants showed seroprotection and a geometric mean titre of 353.6; all 30 Métis participants with no pre-existing antibody showed seroprotection and a geometric mean titre of 376.2. Pain at the injection site and general symptoms frequently occurred but were short-lived and generally not severe, although three participants (2.2%) sought medical attention for general symptoms. Interpretation: First Nations and Métis adults responded robustly to ASO3-adjuvanted pandemic (H1N1) 2009 vaccine. Virtually all participants showed protective titres, including those with chronic health conditions. Trial registration: ClinicalTrials.gov trial register no. NCT.01001026.

Postvaccination thrombocytopenia in Canada.

Active surveillance data from 12 Canadian tertiary-care hospitals on children hospitalized with postvaccination thrombocytopenia were analyzed. Since 1992, there have been 107 cases reported; while 96% of the children were symptomatic, only 2 had severe bleeding. With treatment, 28 children (26%) had normal platelet counts on discharge from hospital and 93% had documented recovery within 3 months.

Prevention of Vertical HIV Transmission and Management of the HIV-Exposed Infant in Canada in 2014

The standard of care for the prevention of vertical transmission (VT) of HIV in Canada and other developed countries includes routine prenatal HIV testing for all pregnant women, and for those testing positive: antepartum combination antiretroviral therapy (cART); intrapartum intravenous zidovudine; six weeks of postnatal oral zidovudine to the infant; and exclusive formula feeding of the infant. With these interventions, the rate of VT has been reduced from 25% to 40%, to 4 weeks before delivery. The purpose of the present article is to highlight recent changes in management guidelines and important caveats to these changes with regard to prevention of VT in the Canadian context. There is a global trend to replace the use of the previous conventional terminology of ‘mother-to-child transmission’ with ‘vertical transmission’ or ‘perinatal transmission’ to remove implications of blame from the mother. In the present article, ‘vertical transmission’ is used throughout. HIV testing during pregnancy HIV testing is recommended for all pregnant women in Canada, with appropriate pre- and post-test counselling. Women whose HIV status is unknown at the time of delivery should undergo rapid HIV antibody testing. For women at increased risk for HIV infection (eg, intravenous drug use, commercial sex work, frequent unprotected intercourse with multiple partners, HIV-negative woman of a serodiscordant couple) who test negative early in pregnancy, repeat testing late in pregnancy (beginning of the third trimester) and at delivery is strongly encouraged. When such women present in labour, advice regarding maternal HIV diagnosis and management should be sought from obstetric and adult HIV experts on an urgent basis; similarly, pediatric HIV experts should be consulted regarding infant management in such situations. Women living with HIV, either previously diagnosed or identified during pregnancy, should be followed by a specialist with expertise in the management of HIV during pregnancy, treated with cART and monitored for viral suppression. Prelabour elective Cesarean section delivery should be planned for those not on cART and/or anticipated or documented to have inadequate viral suppression near delivery (viral load >1000 copies/mL). For women who were previously diagnosed with HIV in whom viral load is not documented to be fully suppressed in the four weeks preceding onset of labour and for women diagnosed with HIV infection at the time of labour, urgent consultation with adult and pediatric HIV experts and an obstetrician with expertise in the management of HIV is essential. Recommendation 1: Pediatricians and other health care providers involved in the care of HIV-infected pregnant women and their children should advocate for universal HIV testing of all pregnant women with appropriate pre- and post-test counselling so that appropriate preventive measures can be implemented in a timely manner. When this fails, testing of the mother at delivery, or of the infant if maternal testing is not possible, should be ensured. Ideally, no infant should be discharged from hospital without the HIV status of the mother being known. Pediatricians and family physicians who perform routine neonatal examinations should verify that the HIV status of the mother or child is known and documented. Recommendation 2: Urgent consultation with an obstetrician with HIV expertise and an adult HIV expert is recommended for diagnosis and management of women deemed to be at high risk for HIV infection with unknown status at the time of labour. Similarly, a pediatric HIV expert should be consulted regarding infant management in such situations.

Development and Evaluation of Global Child Health Educational Modules

OBJECTIVES: To determine if a standardized global child health (GCH) modular course for pediatric residents leads to satisfaction, learning, and behavior change. METHODS: Four 1-hour interactive GCH modules were developed addressing priority GCH topics. “Site champions” from 4 Canadian institutions delivered modules to pediatric residents from their respective programs during academic half-days. A pre–post, mixed methods evaluation incorporated satisfaction surveys, multiple-choice knowledge tests, and focus group discussions involving residents and satisfaction surveys from program directors. RESULTS: A total of 125 trainees participated in ≥1 module. Satisfaction levels were high. Focus group participants reported high satisfaction with the concepts taught and the dynamic, participatory approach used, which incorporated multimedia resources. Mean scores on knowledge tests increased significantly postintervention for 3 of the 4 modules (P < .001), and residents cited increases in their practical knowledge, global health awareness, and motivation to learn about global health. Program directors unanimously agreed that the modules were relevant, interesting, and could be integrated within existing formal training time. CONCLUSIONS: A relatively short, participatory, foundational GCH modular curriculum facilitated knowledge acquisition and attitude change. It could be scaled up and serve as a model for other standardized North American curricula.

Enteric Fever in a Multicultural Canadian Tertiary Care Pediatric Setting: A 28-Year Review

We undertook a 28-year review of enteric fever at a large tertiary care pediatric center. Most cases occurred in children who visited friends and relatives in the Indian subcontinent, and there was significant antibiotic resistance. Documented vaccination rates were low, and many cases also had evidence of delays in diagnosis and treatment.

Missed opportunities for prevention of vertical HIV transmission in Canada, 1997-2016: a surveillance study

BACKGROUND Vertical HIV transmission has declined in Canada, but missed opportunities for prevention continue to occur. We sought to determine the adequacy, and changes over time in adequacy, of uptake of maternal and neonatal antiretroviral therapy for the prevention of vertical HIV transmission, and to determine the vertical transmission rate over time and according to adequacy of antenatal antiretroviral therapy during the combination antiretroviral therapy era in Canada. METHODS The Canadian Perinatal HIV Surveillance Program collects data annually through retrospective chart review concerning HIV-infected women and their infants. We determined receipt of adequate antiretroviral treatment (antenatal combination antiretroviral treatment for ≥ 4 wk, intrapartum intravenous zidovudine treatment and 4-6 wk of infant oral zidovudine treatment) and predictors of inadequate antenatal combination antiretroviral therapy (none or < 4 wk) in Canada in 1997-2016. RESULTS We identified 3785 mother-infant pairs. Uptake of 4 weeks or more of antenatal combination antiretroviral therapy increased over time across all provinces/territories and regardless of maternal race/ethnicity or risk category (p < 0.001). During 2011-2016, 92 women (6.5%) received no or less than 4 weeks of antenatal combination antiretroviral therapy, 146 women (10.7%) received no intrapartum zidovudine treatment, and 43 infants (3.1%) received less than 4 weeks of zidovudine treatment. In multivariate analysis restricted to 2011-2016, higher uptake of adequate antenatal combination antiretroviral therapy was seen among black women than among Indigenous (odds ratio [OR] 2.99, 95% confidence interval [CI] 1.23-7.26) or white (OR 1.87, 95% CI 0.99-1.27) women and in British Columbia/Yukon Territory than in Alberta (OR 3.31, 95% CI 1.06-10.32), Ontario (OR 3.16, 95% CI 1.08-9.26) or Quebec (OR 3.44, 95% CI 1.09-10.84). Among the 14 vertical HIV transmission events during 2011-2016 (vertical transmission rate 1.0%), maternal HIV infection was diagnosed before the onset of labour in 5 cases, and only 2 women received adequate antenatal combination antiretroviral therapy. INTERPRETATION Efforts to improve timely access to care, HIV screening and treatment for all women, combined with enhanced resources targeting populations at increased risk for HIV infection, will be needed if vertical HIV transmission is to be eliminated in Canada.