Subcutaneous nodules following immunization in children; in Victoria, Australia from 2007 to 2016.

BACKGROUND: Subcutaneous nodules are a rare adverse event following immunization (AEFI). We aimed to describe nodules at the injection site reported to SAEFVIC (Surveillance of Adverse Events Following Vaccination in the Community) using the Brighton Collaboration Case Definition (BCCD), management and recurrence following subsequent immunizations. METHOD: We assessed 58 cases (<18 years of age) of 'nodule at injection site' reported to SAEFVIC, Melbourne, Australia, between May 2007 and June 2016. Case details were analyzed from records and phone interview follow-up. The Australian Immunization Registry was reviewed for immunization status. RESULTS: 71% (41/58 reported cases) were consistent with the BCCD for subcutaneous nodule, 14% (8 cases) were 'possible subcutaneous nodules', 10% (6 cases) were nodules associated with BCG immunization and 5% (3 cases) were attributable to an alternative diagnosis. The median age at immunization was 12 months, (range 1 month-12 years); 54% male (22/41 cases). 17% (7 cases) had multiple nodules. Nodules were associated with immunizations containing aluminum (74%, 36/49 nodules), no aluminum (8%, 4 nodules) and unknown (18%, 9 nodules). Most cases developed symptoms within 3 days post-immunization (59%, 24 cases) and in the thigh (59%, 29 nodules). Pruritus was associated in 41% (17 cases). Around 1/3 (34%) of nodules resolved 6 months post immunization, 2/3 (68%) by 12 months, however 1/4 (24%) remained persistent for >24 months. 5 cases had prior nodules and 1 case had recurrence with subsequent immunization. 83% (34 cases) were fully immunized for age at follow-up. CONCLUSION: Subcutaneous nodules at the injection site may occur following a wide range of vaccines, including vaccines without aluminum. All cases require careful review and where possible, specialist management and to support subsequent immunizations.

Recurrence risk of a hypotonic hyporesponsive episode in two Australian specialist immunisation clinics.

BACKGROUND: A hypotonic hyporesponsive episode (HHE) is a well-described adverse event following immunisation (AEFI) in young children. There is limited data regarding recurrence post re-vaccination. METHOD: A retrospective analysis of HHEs reported to two tertiary paediatric hospitals in Australia: The Royal Children's Hospital, Melbourne [2006-11] and the Children's Hospital Westmead, Sydney [1997-2014]. HHE definition level of confidence was allocated according to Brighton Collaboration (BC) criteria and defined immediate if within 30 min post vaccination. The Australian Immunisation Register (AIR) was utilised to document current immunisation status. RESULTS: 235 HHE cases (135 Melbourne, 100 Sydney) were identified: 47% were female and 67% (157/235) occurred following the routine dose one vaccines at 6-8 weeks of age. Median time following immunisation was 120 min (range 1 min to 14 days) An immediate HHE occurred in 43% (102/235) and by BC criteria, 74% (173/235) were level 1 (definite). Subsequent vaccines were administered under supervision in hospital in 37% overall (86/235); 43% (58/135) in Melbourne and 28% (28/100) in Sydney. HHE recurrence rate was 3% (7/235) [95% confidence interval 1-6%]. AIR records were available in 94% (221/235). At a median age of 3.1 years, 84% (186/221) were up-to-date with recommended vaccines. CONCLUSION: This study highlights the importance of specialist immunization clinics in supporting the National Immunisation Program, through follow-up and management of serious adverse events following immunization.

Recurrent apnoea post immunisation: Informing re-immunisation policy.

BACKGROUND: Preterm infants should receive immunisations according to their chronological, rather than gestational, age however concern about possible adverse events following immunisation (AEFI) in this group often means routine immunisations are delayed. A small number of infants may have apnoea with or without bradycardia temporally associated with immunisation. The risk factors for, and recurrence rate of apnoea with subsequent immunisations are unknown, which makes planning for subsequent immunisations for these highly vulnerable infants difficult. AIM: To determine recurrence rates for apnoea temporally associated with immunisation in preterm and term infants and to explore potential risk factors associated with recurrent apnoea in preterm infants. METHOD: A retrospective analysis of all apnoea +/-bradycardia AEFIs in preterm and term infants, reported to the Surveillance of Adverse Events Following Vaccination In the Community (SAEFVIC), Victoria, Australia over a 3-year period from May 2007 to April 2010. Apnoea +/-bradycardia was defined as temporally associated with immunisation if it occurred up to 48h after immunisation. RESULTS: 7 out of 38 [18%, 95% confidence interval 6-31%] preterm infants with apnoea +/-bradycardia post initial immunisation had recurrent apnoea with subsequent immunisations. Possible risk factors for recurrence included: lower birth weight (p=0.04) and ongoing hospitalisation for complications relating to prematurity (p=0.01). No preterm infant with recurrent apnoea had a third episode of apnoea with subsequent immunisation. None of the 8 term infants with a reported apnoea AEFI had recurrence of apnoea with subsequent immunisation. CONCLUSION: There is a risk of recurrence of apnoea associated with immunisation in preterm infants. We recommend that preterm infants with apnoea post immunisation should receive reliable cardio-respiratory monitoring for a minimum of 24h following the next scheduled immunisation.

Syncope and seizures following human papillomavirus vaccination: a retrospective case series.

OBJECTIVE: To quantify and characterise the reports of syncope and seizures following quadrivalent (4v) human papillomavirus (HPV) vaccination. DESIGN AND SETTING: Retrospective case series of notifications to SAEFVIC (Surveillance of Adverse Events Following Vaccination In the Community), May 2007 - April 2009. MAIN OUTCOME MEASURES: Incidence of syncope and seizure following 4vHPV vaccination; clinical outcomes. RESULTS: 97/1653 SAEFVIC reports met the study criteria: afebrile seizures (3), syncopal seizures (31) and syncope alone (63). Median age at vaccination was 15 years (range, 8-26 years). Injuries were reported in seven cases, including one vertebral fracture. A SAEFVIC clinic review was undertaken in 41% (40/97) and 22 patients received further 4vHPV vaccine doses administered supine, with no recurrences. The reporting rate after 4vHPV vaccine for syncope and syncopal seizures was 7.8/100, 000 and 2.6/100, 000 doses distributed, respectively. CONCLUSION: Syncope and syncopal seizures occurred after 4vHPV vaccination in Victoria at rates similar to those seen internationally. Clinical review allowed clarification of the diagnosis and management, including safe administration of further doses under supervision.

Respiratory syncytial virus infection and recurrent wheeze/asthma in children under five years: an epidemiological survey.

AIM: To determine the rates of respiratory syncytial virus (RSV) infection in children under 5 years of age with recurrent wheeze or asthma and compare their clinical presentation, course and outcome with asthmatic children of the same age who did not have RSV. METHODS: Children were recruited prospectively from the emergency department of the Royal Children's Hospital, Melbourne during peak RSV season in 1998. Information was collected regarding past and current asthma presentations, a nasopharyngeal asprirate was taken for viral isolation and all children were reviewed by telephone 1 week following presentation. RESULTS: 73 children were included with a median age of 28 months. RSV was isolated from 33 (45%) of children, one child had adenovirus and in the remainder no virus was isolated. Children less than 12 months were more likely to have RSV (70%). RSV-positive children had a longer duration of illness prior to hospital presentation than RSV-negative children but were not more likely to be admitted or to have a longer duration of ongoing symptoms. CONCLUSION: A high rate of RSV infection was demonstrated in young children with recurrent wheeze or asthma during the RSV season. This information has important implications for the control of nosocomial infection with RSV (i.e. isolation of patients) and in targeting another group to be included for RSV vaccine development.