Comparative Analysis of Symptomatic and Asymptomatic SARS-CoV-2 Infection in Children

INTRODUCTION

In this study, a comparison of clinical, epidemiological and laboratory parameters between symptomatic and asymptomatic children with SARS-CoV-2 infection was performed.

MATERIALS AND METHODS

Data from all children with laboratory confirmed SARS-CoV-2 infection admitted to KK Women's and Children's Hospital (KKH), Singapore, from January to May 2020 were analysed.

RESULTS

Of the 39 COVID-19 children included, 38.5% were asymptomatic. Household transmission accounted for 95% of cases. The presenting symptoms of symptomatic children were low-grade fever (54.2%), rhinorrhoea (45.8%), sore throat (25%), diarrhoea (12.5%) and acute olfactory dysfunction (5.4%). Children of Chinese ethnicity (37.5% vs 6.7%), complete blood count (45.8% vs 6.7%) and liver enzyme abnormalities (25% vs 7.7%) were more common in symptomatic versus asymptomatic children. All children had a mild disease course and none required oxygen supplementation or intensive care.

CONCLUSIONS

The high proportion of asymptomatic infected children coupled with household transmission as the main source of paediatric COVID-19 infection underscores the importance of early screening and isolation of children upon detection of an index case of COVID-19 in a household. Symptomatic children were more likely to have abnormal laboratory parameters but they did not have a poorer outcome compared to asymptomatic cases.

Successful containment of horizontal enterovirus infection in a neonatal unit in Singapore through diagnosis by polymerase chain reaction (PCR) and direct sequence analysis

BACKGROUND

Enterovirus (EV) outbreaks often coincide with seasonal peaks in the community. However, they may also sporadically occur in neonatal units. Identification of EV infection in neonates can be challenging, as they tend to present with mild or nonspecific symptoms. This study reports an EV outbreak in the Neonatal Unit at KK Women's and Children's Hospital, Singapore.

METHODS

This is a single-center, retrospective cohort study of neonates who had positive results for EV during the outbreak. Demographic characteristics, clinical presentations and outcomes were analyzed. Control measures used to limit the spread of infection are reported.

RESULTS

A total of 7 cases of EV infection were identified. Their median birth weight and gestational age were 1240 g (750 -2890 g) and 28 weeks (26-35 weeks), respectively. Symptoms occurred at a median age of 48 days (9-103 days). All cases presented initially with recurrent apnea and 4 needed assisted ventilator support with CPAP (2) and mechanical ventilation (2). Serious complications occurred in 3 infants (2 with necrotizing enterocolitis and 1 with meningitis) and none died. EV was detected from rectal swabs (n = 6), CSF (n = 2) and nasopharyngeal swabs (n = 2). Viral subtyping uniformly revealed echovirus 25. Surveillance of all exposed infants by nasopharyngeal swabs was implemented, along with strict contact precautions and cohorting measures.

CONCLUSIONS

Premature infants with EV are more prone to serious complications, which can lead to significant morbidity. Thus, early recognition of symptoms, rapid diagnosis and prompt implementation of infection control measures are key to prevent further spread of infection.

Clinical Utility of Buccal Swabs for Severe Acute Respiratory Syndrome Coronavirus 2 Detection in Coronavirus Disease 2019-Infected Children

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detected from at least 1 buccal specimen in 9 of 11 coronavirus disease 2019 (COVID-19)-infected children (81.8%). Viral loads in buccal specimens were substantially lower than those in nasopharyngeal specimens. Buccal swabs are not good as COVID-19 screening specimens in children.

Invasive paediatric Elizabethkingia meningoseptica infections are best treated with a combination of piperacillin/tazobactam and trimethoprim/sulfamethoxazole or fluoroquinolone

Objectives

Elizabethkingia meningoseptica is a multi-drug-resistant organism that is associated with high mortality and morbidity in newborn and immunocompromised patients. This study aimed to identify the best antimicrobial therapy for treating this infection.

Methods

A retrospective descriptive study was conducted from 2010 to 2017 in a tertiary paediatric hospital in Singapore. Paediatric patients aged 0 to 18 years old with a positive culture for E. meningoseptica from any sterile site were identified from the hospital laboratory database. The data collected included clinical characteristics, antimicrobial susceptibility and treatment, and clinical outcomes.

Results

Thirteen cases were identified in this study. Combination therapy with piperacillin/tazobactam and trimethoprim/sulfamethoxazole or a fluoroquinolone resulted in a cure rate of 81.8  %. The mortality rate was 15.4  % and neurological morbidity in patients with bacteraemia and meningitis remained high (75 %).

Conclusions

Treatment with combination therapy of piperacillin/tazobactam and trimethoprim/sulfamethoxazole or a fluroquinolone was effective in this study, with low mortality rates being observed.

Elizabethkingia anophelis and Association with Tap Water and Handwashing, Singapore

We report an Elizabethkingia anophelis case cluster associated with contaminated aerators and tap water in a children’s intensive care unit in Singapore in 2017. We demonstrate a likely transmission route for E. anophelis to patients through acquisition of the bacteria on hands of healthcare workers via handwashing.

2341. Trends in Adenovirus Infections in Singapore Children and Outcomes of Cidofovir Treatment in the Severely Ill

Background

An increase in human adenovirus (HAdV) infections among hospitalized children in Singapore was observed since 2013. Cidofovir is often used to treat severe HAdV infections despite limited data. This study describes the epidemiology and outcomes of children with severe HAdV disease requiring high dependency (HD) or intensive care unit (ICU) admission in our hospital (KKH).

Methods

This is a retrospective cohort study of HAdV-infected children admitted to HD and ICU in KKH from January 2013 to September 2017. Characteristics and outcomes of those who received IV cidofovir was also reviewed.

Results

HAdV admissions and genotype profiles in KKH are described in Figures 1 and 2, respectively. There were 85 children with severe HAdV infection, of which 17 (20%) received cidofovir for mainly viremia (8, 47.1%) and pneumonia (7, 41.2%). Of these 17 patients, 7 (41.2%) died. More children treated with cidofovir had genotype 7 infection (8 of 17, 47.1%) vs. 13 of 68 (19.1%) who did not (P = 0.027). Characteristics of patients who received cidofovir are described in Table 1. None experienced adverse reactions from cidofovir.

All are n (%) unless stated otherwise.

Conclusion

More children with HAdV genotype 7 infection required cidofovir treatment. HAdV pneumonia and ICU admission are potential risk factors for mortality despite cidofovir treatment.

Disclosures

All authors: No reported disclosures.

Pragmatic and evidence-based approach to paediatric cerebrospinal fluid reference limits for white cell count and concentrations of total protein and glucose

Background

It is often impractical for each laboratory to establish its own paediatric reference intervals. This is particularly true for specimen types collected using invasive procedures, for example, cerebrospinal fluid (CSF).

Methods

Published CSF reference intervals for white cell count, and concentrations of total protein and glucose were reviewed by stakeholders in a paediatric hospital. Consensus reference intervals for the three CSF parameters were then subjected to verification using guidelines from the Clinical Laboratory Standards Institute and residual CSF specimens.

Results

Consensus paediatric reference intervals adapted from published studies with minor modifications were locally verified as follows. White cell count (x106 cells/L): 0–20 (<1 month); 0–10 (1–2 months); 0–5 (>2 months). Total protein (g/L): 0.3–1.2 (<1 month); 0.2–0.6 (1–3 months); 0.1–0.4 (>3 months). Glucose (mmol/L): 2.0–5.6 (<6 months); 2.4–4.3 (6 months or older).

Quantitative NMR spectroscopy for gas analysis for production of primary reference gas mixtures

Due to its direct correlation to the number of spins within a sample quantitative NMR spectroscopy (qNMR) is a promising method with absolute comparison abilities in complex systems in technical, as well as metrological applications. Most of the samples studied with qNMR are in liquid state in diluted solutions, while gas-phase applications represent a rarely applied case. Commercially available NMR equipment was used for purity assessment of liquid and liquefied hydrocarbons serving as raw materials for production of primary reference gas standards. Additionally, gas-phase studies were performed within an online NMR flow probe, as well as in a high-pressure NMR setup to check feasibility as verification method for the composition of gas mixtures.

A 15-year retrospective analysis of prognostic factors in childhood bacterial meningitis

AIM

This retrospective chart review aimed to identify factors in childhood bacterial meningitis that predicted disease severity and long-term outcome.

METHODS

The study included 112 episodes of microbiologically confirmed bacterial meningitis in children aged three days to 15 years who were admitted to a Singapore hospital from 1998 to 2013.

RESULTS

The mortality rate was 6%, and 44% required intensive care unit (ICU) admission. Predictive factors associated with ICU admission included pneumococcal meningitis, with an odds ratio (OR) of 5.2 and 95% confidence interval (CI) of 1.5-18.2, leukopenia (OR 5.6, 95% CI 1.7-17.9) and a cerebrospinal fluid (CSF):serum glucose ratio <0.25 (OR 4.5, 95% CI 1.4-14.4). An initial CSF white blood cell count >1000/mm(3) (OR 0.26, 95% CI 0.086-0.76) was negatively associated with ICU admission. Five years after meningitis, 32% had residual sequelae, and the associated prognostic factors were Haemophilus influenzae type b (Hib) meningitis (OR 29.5, 95% CI 2-429), seizures during their inpatient stay (OR 10.6, 95% CI 1.9-60.2) and septic shock (OR 8.4, 95% CI 1.1-62.1).

CONCLUSION

As mortality was low in this bacterial meningitis study, ICU admission was used as a marker of disease severity. These findings underscore the importance of the pneumococcal and Hib meningitis vaccines.

Single-pass UV generation at 222.5 nm based on high-power GaN external cavity diode laser

We demonstrate a compact system for single-pass frequency doubling of high-power GaN diode laser radiation. The deep UV laser light at 222.5 nm is generated in a β-BaB2O4 (BBO) crystal. A high-power GaN external cavity diode laser (ECDL) system in Littrow configuration with narrowband emission at 445 nm is used as pump source. At a pump power of 680 mW, a maximum UV power of 16 μW in continuous-wave operation at 222.5 nm is achieved. This concept enables a compact diode laser-based system emitting in the deep ultraviolet spectral range.

Risk Factors for Severe Adenovirus Infection in Children during an Outbreak in Singapore

BACKGROUND

Human adenoviruses (HAdVs) can cause a variety of human illnesses, with associated temporal and geographic changes in disease incidence. We report the emergence of an outbreak of HAdV infections in Singapore, presumably caused by a change of the predominating type to HAdV-7. We examined the clinical features of children admitted with HAdV infection to 1 institution and the risk factors for severe infection.

MATERIALS AND METHODS

This is a retrospective case-control study of all HAdV-infected children admitted during weeks 1 to 19 in 2013, as identified from laboratory records. A descriptive retrospective analysis of epidemiology, clinical data and the outcome of these children was also performed. Patients with severe infections were defined as cases, those with non-severe infections as controls, and the 2 groups were compared to find possible independent risk factors.

RESULTS

Eighty-five patients with HAdV infection were studied, including 11 (12.9%) cases and 74 (87.1%) controls. Binary logistic regression showed that cases were more likely to be <2 years old (adjusted OR 10.6, 95% CI, 1.8 to 63.2) and to have significant comorbidities (adjusted OR 19.9, 95% CI, 3.4 to 116.1) compared to controls. The predominant type in 2013 was HAdV-7, which differed from 2011 and 2012, when HAdV-3 was more common. There was a trend towards pneumonia being more common in patients infected with HAdV-7 than in patients infected with other types, although this did not reach statistical significance (OR 2.8, 95% CI, 0.9 to 8.7).

CONCLUSION

The emergence of HAdV-7 in a population where other HAdV types had circulated previously may have caused the outbreak in Singapore, and this was associated with more serious infections in children. Young age (<2 years) and significant comorbidities were associated with more severe HAdV infection.