Australian Paediatric Surveillance Unit Annual Report 2018

Severe Influenza-Associated Neurological Disease in Australian Children: Seasonal Population-Based Surveillance 2008-2018

BACKGROUND

Influenza-associated neurological disease (IAND) is uncommon but can result in death or neurological morbidity in children. We aimed to describe the incidence, risk factors, and outcome of children with IAND from seasonal influenza in Australia.

METHODS

We analyzed national, population-based, surveillance data for children aged ≤ 14 years with severe influenza and neurological involvement, over 11 Australian influenza seasons, 2008-2018, by the Australian Paediatric Surveillance Unit.

RESULTS

There were 633 laboratory-confirmed cases of severe influenza reported. Of these, 165 (26%) had IAND. The average annual incidence for IAND was 3.39 per million children aged ≤ 14 years. Compared to cases without neurological complications, those with IAND were more likely to have a pre-existing neurological disease (odds ratio [OR] 3.03, P < .001), but most children with IAND did not (n = 135, 82%). Children with IAND were more likely to receive antivirals (OR 1.80, P = .002), require intensive care (OR 1.79, P = .001), require ventilation (OR 1.99; P = .001), and die (OR 2.83, P = .004).

CONCLUSIONS

IAND is a preventable cause of mortality, predominantly in otherwise well children. Incidence estimates validate previous sentinel site estimates from Australia. IAND accounted for a quarter of all severe influenza, is associated with intensive care unit admission, and accounted for half of all influenza deaths.

Australian Paediatric Surveillance Unit (APSU) Annual Surveillance Report 2020

Abstract

For 27 years, national prospective data on selected rare childhood diseases have been collected monthly by the Australian Paediatric Surveillance Unit (APSU) from paediatricians and other clinical specialists who report cases in children aged up to 16 years. We report here the annual results of APSU surveillance in 2020 for ten rare communicable diseases and complications of communicable diseases, namely: acute flaccid paralysis (AFP); congenital cytomegalovirus (CMV) infection; neonatal herpes simplex virus (HSV) infection; perinatal exposure to human immunodeficiency virus (HIV); paediatric HIV infection; severe complications of seasonal influenza; juvenile onset recurrent respiratory papillomatosis (JoRRP); congenital rubella syndrome; congenital varicella syndrome; and neonatal varicella infection. We describe the results for each disease in the context of the total period of study, including demographics, clinical characteristics, treatment and short-term outcomes. Despite challenges presented by the coronavirus disease 2019 (COVID-19) pandemic in 2020, more than 1,400 paediatricians reported regularly to the APSU and an overall monthly reporting rate of > 90% was achieved. The minimum AFP target of 1 case per 100,000 children aged less than 15 years was achieved and there were few cases of vaccine-preventable diseases (JoRRP, rubella, varicella). However, high cases of congenital CMV, neonatal HSV and perinatal exposure to HIV persist. There were no severe complications of seasonal influenza reported for the first time in 13 years. This is consistent with other surveillance data reporting a decline of influenza and other communicable diseases in 2020, and likely reflects the wider effects of public health measures to reduce transmission of SARS-CoV-2 in the Australian community.

Microcephaly in Australian children, 2016-2018: national surveillance study

OBJECTIVE

To describe infants aged <12 months reported with microcephaly to the Australian Paediatric Surveillance Unit (APSU) following emergence of Zika virus infection internationally.

DESIGN, SETTING AND PATIENTS

National, active, monthly surveillance for microcephaly using the APSU. Microcephaly was defined as occipitofrontal circumference (OFC) of more than 2 SDs below the mean for age, gender and gestation.

MAIN OUTCOME MEASURES

Clinical spectrum, aetiology and birth prevalence of microcephaly reported by paediatricians.

RESULTS

Between June 2016 and July 2018, 106 notifications were received, with clinical details provided for 96 (91%). After excluding ineligible notifications, 70 cases were confirmed, giving an annual birth prevalence of 1.12 (95% CI 0.88 to 1.42) per 10 000 live births. Of the total number of cases, 47 (67%) had primary microcephaly (at birth); and 25 (36%) had severe microcephaly (OFC >3 SDs). Birth defects were reported in 42 (60%). Of 49 infants with developmental assessment details available, 25 (51%) had failed to reach all milestones. Vision impairment was reported in 14 (26%). The cause of microcephaly was unknown in 60%: 13 (19%) had been diagnosed with genetic disorders; 22 (39%) had anomalies on neuroimaging. No congenital or probable Zika infection was identified. Severe microcephaly was more often associated with hearing impairment than microcephaly of >2 SDs but ≤3 SDs below the mean (p<0.007). Indigenous children and children with socioeconomic advantage were over-represented among children with microcephaly.

CONCLUSION

Novel national data on microcephaly highlight the high proportion of idiopathic cases. This has implications for prevention and management and suggests the need for a standardised diagnostic approach and ongoing surveillance mechanism in Australia.

Herpes Simplex Virus Infection in Infants: 13 Year Evaluation (2005-2017) of Laboratory Confirmed Cases in Queensland, Australia

BACKGROUND

National neonatal surveillance for herpes simplex virus (HSV) disease suggests that the incidence of HSV disease may be higher in Queensland (QLD) than in other Australian States. We sought to investigate the incidence via a retrospective 13-year evaluation of statewide laboratory data, autopsy data and linked clinical records of infants with laboratory confirmed infection.

METHODS

All positive polymerase chain reaction HSV 1 and 2 results were obtained for infants 0-3 months of age from January 1, 2005 to December 31, 2017. Clinical data were obtained from patient records and parent questionnaires were used to evaluate long-term sequelae.

RESULTS

One hundred seventy-two infants with HSV positive polymerase chain reaction results: 121 (70.3%) with HSV 1. Of 104 (60.5%) infants with signs of HSV disease, 76 (73.1%) were neonates (≤28 days of age) [incidence 9.6 (95% confidence interval, 7.0-11.5) per 100,000 live births] and 28 (26.9%) were young infants (29-90 days of age) [3.6 (95% confidence interval, 2.4-5.4) per 100,000 live births]. The annual incidence of neonatal HSV disease increased significantly in Queensland over the study period (P < 0.01). Of the 76 neonates with HSV disease, 58 (76.3%) presented with the skin, eye, mouth (SEM) disease, 17 (22.4%) with HSV encephalitis and 11 (14.5%) had disseminated disease. Young infants presented with HSV skin, eye, mouth disease (21, 75.0%) or HSV encephalitis (6, 21.4%). Death occurred in 12/104 (11.5%) infants (all neonates) with 10 attributable to HSV disease.

CONCLUSION

The incidence of neonatal HSV disease in QLD is almost 3 times the national reported incidence. Further research is being undertaken to explore reasons for this change and implications for practice.

Australian Paediatric Surveillance Unit (APSU) Annual Surveillance Report 2019

The Australian Paediatric Surveillance Unit (APSU) has been prospectively collecting national data on rare childhood conditions since 1993, with monthly reporting of cases by paediatricians. In this report we describe annual results from studies for ten communicable diseases and complications of communicable diseases that were conducted using APSU surveillance in 2019 and place these in an historic context. Results are reported on acute flaccid paralysis, congenital cytomegalovirus infection, neonatal herpes simplex virus infection, perinatal exposure to HIV, paediatric HIV infection, severe complications of seasonal influenza, juvenile onset recurrent respiratory papillomatosis (JoRRP), congenital rubella syndrome, congenital varicella syndrome and neonatal varicella infection. APSU provides rich clinical data to complement data collected from other surveillance systems and to improve understanding and response to rare childhood infections.