Adverse events following immunisation: Prospective cohort study evaluating Australian children presenting to specialist immunisation clinics.

OBJECTIVE: Prior experience of an adverse event following immunisation is a known barrier to vaccination. Limited Australian data evaluating adverse event recurrence among children exists to inform clinical decisions. We aimed to assess adverse event following immunisation recurrence among children with prior adverse events and to evaluate if family history increased adverse event risk. METHODS: A prospective cohort study was conducted from March 3rd until August 18th, 2023. Children ≤ 16 years with prior adverse events following immunisation in themselves or family were recruited from specialist immunisation clinics at two quaternary paediatric hospitals. Adverse event outcomes were collected via surveys administered at presentation, three, and eight days post vaccination, and analysed by key characteristics and potential risk factors. RESULTS: Forty three of forty nine (43/49, 87.8 %) children enrolled received further vaccines. Of those who completed the follow up surveys, 50.0 % (16/32) reported an adverse event. Recurrence of prior adverse events occurred for 23.3 % (10/43, 95 % CI: 11.8 % - 38.6 %) of the cohort. Two of twelve (2/12, 16.7 %) participants with prior serious adverse events who received further vaccines reported a serious adverse event recurrence. No post review serious adverse events were observed in children with prior non serious adverse events. Neurological conditions were a risk factor for prior (neurological condition 3/3 versus no neurological condition 2/40, p < 0.001) and post review (neurological condition 2/3 versus no neurological condition 0/28, p = 0.006) post vaccination seizures. Family history had no relationship to post review adverse events (family history 5/8 versus no family history 11/23, p = 0.685). CONCLUSION: Revaccination is safe for the majority of children with a personal or family history of adverse event following immunisation.

Impact of Infectious Diseases Consultation on Management and Outcome of Staphylococcus aureus Bacteremia in Children.

BACKGROUND: To examine the impact of infectious diseases consultation (IDC) on the management and outcome of Staphylococcus aureus bacteremia (SAB) in children. METHODS: A retrospective cohort study of children with SAB at a teritary pediatric hospital (January 2009-June 2015) identified by medical record review as to whether they received an IDC for SAB at the discretion of the admitting physician or surgeon was conducted. Differences in management and outcomes for those with and without IDC were evaluated, and multivariate regression analysis was used to determine factors associated with cure. RESULTS: There were 100 patients included in the analysis. Fifty-five patients received IDC and 45 had no IDC (NIDC). Appropriate directed therapy within 24 hours (54/55 = 98.2% vs 34/45 = 75.6%, P < .01), choice (54/55 = 98.2% vs 37/45 = 82.2%, P < .01), dose (54/55 = 98.2% vs 36/45 = 80%, P < .01), and duration (52/55 = 94.5% vs 24/45 = 53.3%, P < .01) of directed antibiotic therapy were appropriate in more IDC group patients. Achievement of source control in indicated cases was also more common in the IDC group (28/32 = 87.5% vs 5/26 = 19.1%, P < .01). Appropriate investigation with repeat blood cultures and echocardiograms was not significantly different. All 55 patients in the IDC group had a complete response (cure) compared with 40 of the 45 (88.9%) patients in the NIDC group: 2 patients died and 3 patients had a relapse of infection with subsequent cure. In multivariate regression analysis, methicillin-susceptible SAB and IDC were factors independently associated with cure. CONCLUSIONS: Children who received IDC for SAB in a tertiary pediatric setting were more likely to have appropriate investigations and management and had improved outcomes.