Paediatric Active Enhanced Disease Surveillance (PAEDS) 2019: Prospective hospital-based surveillance for serious paediatric conditions

Herpes simplex virus in infancy: Evaluation of national surveillance case capture

AIM

As herpes simplex virus (HSV) in infancy is not a mandatory notifiable condition in Australia, completeness of ascertainment by the Australian Paediatric Surveillance Unit (APSU) has been difficult to evaluate to date. We evaluated case capture in Queensland (QLD) and Western Australia (WA) using statewide laboratory and clinical data and complementary surveillance data collected via the APSU.

METHODS

HSV polymerase chain reaction positive results in infants (0-3 months) from 2007 to 2017 were obtained from statewide public pathology providers in QLD and WA. Clinical data were extracted from patient records and compared to APSU reported cases.

RESULTS

A total of 94 cases of HSV disease in infancy (70 QLD; 24 WA) were identified from laboratory data sets, compared to 36 cases (26 QLD; 10 WA) reported to the APSU. In total there was 102 unique cases identified; 28 cases were common to both data sets (seven skin eye mouth (SEM) disease, 13 central nervous system (CNS) disease and eight disseminated disease). Active surveillance captured 35% (36/102) of cases overall including 74% (14/19) of CNS, 71% (10/14) of disseminated and 17% (12/69) of SEM disease cases, respectively. Surveillance reported cases had a higher case-fatality rate compared to those not reported (14% vs. 3%, P = 0.038). Neurological sequelae at discharge were comparable between the groups.

CONCLUSION

Active surveillance captures one third of hospitalised HSV cases in QLD and WA, including the majority with severe disease. However, morbidity and mortality remain high. Future studies on HSV will rely on observational studies. Enhanced case ascertainment through combined laboratory and surveillance data is essential for better understanding and improving outcomes.

Improving knowledge of rare disorders since 1993: the Australian Paediatric Surveillance Unit

The Australian Paediatric Surveillance Unit (APSU), established in 1993 to address the paucity of national data on rare childhood disorders, has become an invaluable research resource. It facilitates prospective, active surveillance for a variety of rare disorders, with monthly reporting by ~1500 paediatricians, who are invited to notify incident cases and provide demographic and clinical data. APSU is highly collaborative (used by >400 individuals/organisations), patient-informed and productive (>300 publications). In 30 years, 72 studies have been initiated on rare infections, and genetic, psychological and neurological disorders, and injuries. Return rates of monthly report cards were >90% for 30 years and paediatricians have provided data for >90% of notified cases. Although there are limitations, including case underascertainment in remote regions, APSU often provides the only available national data. APSU has assisted the government in reporting to the WHO, developing national strategies, informing inquiries and investigating disease outbreaks. APSU data have informed paediatrician education, practice, policy, and service development and delivery. APSU was integral in establishing the International Network of Paediatric Surveillance Units (INoPSU) and supporting development of other units. APSU's expanded remit includes one-off surveys, hospital audits, systematic reviews, studies on the impacts of rare disorders on families, surveillance evaluations, and joint studies with INoPSU members. Paediatricians value the APSU, reporting that APSU data inform their practice. They must be congratulated for an outstanding collective commitment to the APSU, in providing unique data that contribute to our understanding of rare disorders and support optimal, evidence-based care and improved child health outcomes.

Review of the health impact of the oral rotavirus vaccine program in children under 5 years in Australia: 2006 - 2021

Oral rotavirus vaccines were incorporated into the National Immunisation Program (NIP) for all Australian infants in July 2007. Initially each of the eight jurisdictions implemented Rotarix or RotaTeq rotavirus vaccine, however from July 2017 all states and territories have administered Rotarix only. This review evaluates the health impact of the oral rotavirus vaccine program for Australian children less than 5 years old over the first 15 years of the rotavirus vaccine program, observing long-term changes in rotavirus-related health care attendances, public health notifications, and vaccine effectiveness and safety data for both Rotarix and RotaTeq rotavirus vaccines. We searched Medline for studies published between January 2006 and May 2022 using the search terms 'rotavirus', 'rotavirus vaccine' and 'Australia'. Of 491 items identified, 76 items - 36 peer-reviewed articles and 40 reports - were included in the review. We found evidence that the introduction of the oral rotavirus vaccine program in Australia was associated with a prompt reduction in rotavirus-coded and all-cause gastroenteritis hospitalisations of vaccine-eligible children. In the context of less complete coverage, reduced vaccine timeliness and lower vaccine effectiveness, a less substantial and inconsistent reduction in severe rotavirus disease was observed among Aboriginal and Torres Strait Islander children, particularly those living in rural and remote northern Australia. Additional studies report no evidence for the emergence of non-vaccine serotypes and/ or replacement serotypes in Australia during the vaccine era. While the health impact for young children and consequent cost-savings of the oral rotavirus vaccine program have been high, it is important to find strategies to improve rotavirus vaccine impact for Aboriginal and Torres Strait Islander populations to ensure health benefits for all Australian children.

A narrative review of vaccine pharmacovigilance during mass vaccination campaigns: Focus on myocarditis and pericarditis after COVID-19 mRNA vaccination

Vaccines have had a tremendous impact on reducing the burden of infectious diseases; however, they have the potential to cause adverse events following immunization (AEFIs). Prelicensure clinical trials are limited in their ability to detect rare AEFIs that may occur in less than one per thousand individuals. While postmarketing surveillance systems have shown COVID-19 mRNA vaccines to be safe, they led to the identification of rare cases of myocarditis and pericarditis after COVID-19 vaccination that were not initially detected in clinical trials. In this narrative review, we highlight concepts of vaccine pharmacovigilance during mass vaccination campaigns and compare the approaches used in the context of myocarditis and pericarditis following COVID-19 vaccination to historical examples. We describe mechanisms of passive and active surveillance, their strengths and limitations, and how they interacted to identify and characterize the safety signal of myocarditis and pericarditis after COVID-19 mRNA vaccination. Articles were synthesized from a PubMed search using relevant keywords for articles published on vaccine surveillance systems and myocarditis and pericarditis after COVID-19 vaccination, as well as the authors' collections of relevant publications and grey literature reports. The global experience around the identification and monitoring of myocarditis and pericarditis after COVID-19 mRNA vaccination has provided important lessons for vaccine safety surveillance and highlighted its importance in maintaining public trust in mass vaccination programmes in a pandemic context.