SARS-CoV-2 Variants and Age-Dependent Infection Rates among Household and Nonhousehold Contacts.

To determine the effects of age and variants of concern on transmission of SARS-CoV-2, we analyzed infection rates among close contacts over 4 periods in Toyama Prefecture, Japan. Among household contacts, odds of infection were 6.2 times higher during the period of the Omicron variant than during previous periods, particularly among children and adolescents.

Comparison of sinus conversion rates and body weights after 6 mg adenosine administration in supraventricular tachycardia.

BACKGROUND: To evaluate the relationship between body weight and the success rate of supraventricular tachycardia (SVT) termination after an initial 6-mg adenosine administration. METHODS: This retrospective observational study was conducted with medical records of patients who visited a single tertiary emergency department and underwent an electrophysiologic study with an SVT diagnosis. Patients under 18 years of age or those with SVT aberrancy, recurring SVT after radiofrequency catheter ablation, premedication of non-dihydropyridine calcium channel blocker, and signs of shock were excluded. RESULTS: Data from 124 patients were collected. There were 69 women (55.6%); mean age, 49.7 years. The mean weight and height were 66.8 kg and 164.8 cm, respectively. Adenosine dose was 0.09 mg/kg. For the first sinus conversion (SC) success group (83 patients, 67%), the mean weight, height, and adenosine dose were 61.0 ± 11.5 kg, 161.9 ± 8.1 cm, and 0.10 ± 0.02 mg/kg. For the first SC failure group, these values were 78.4 ± 17.0 kg, 170.7 ± 8.9 cm, and 0.079 ± 0.02 mg/kg, respectively. To evaluate factors associated with the first SC, we performed bivariate logistic regression with weight (odds ratio [OR]: 1.093; 95% confidence interval [CI]: 1.045-1.144; P < 0.001) and height (OR: 1.071; 95% CI: 1.008-1.138; P = 0.027). Receiver operating characteristics curves and the cut-off values for adenosine dose and weight were 0.90 mg/kg and 66.5 kg with 71.1% sensitivity and 73.2% specificity (area under the curve: 0.814; 95% CI: 0.73-0.90; P < 0.001). CONCLUSION: Weight and height were significant predictors of the first SC success rate among SVT patients. Consequentially, it is necessary to consider other adenosine administration methods, including increasing the initial drug dose or changing the flushing strategy after adenosine injection.

An unexpected effect of traumatic and bloody lumbar puncture among patients with primary headaches in emergency department.

BACKGROUND: This study aimed to investigate the association between traumatic tap and the incidence of post-dural puncture headache (PDPH) following lumbar puncture (LP) among patients who underwent LP with a primary discharge diagnosis of primary headache in the emergency department (ED). METHODS: We retrospectively reviewed the medical records of patients who visited a single tertiary ED with the symptom of a headache and underwent LP for cerebrospinal fluid (CSF) analysis between January 2012 and January 2022. Patients who met the definition of PDPH and revisited the ED or outpatient clinic within 2 weeks of discharge were included. For comparative analysis, we divided the groups according to CSF RBC counts (group 1, CSF RBC <10 cells/µL; group 2, 10-100 cells/µL; group 3, ≥100 cells/µL). The primary outcome was the difference in CSF RBC counts between the ED or outpatient clinic revisiting patients who underwent LP within 2 weeks after discharge from the ED. The secondary outcomes were the admission rate and risk factors for PDPH; sex, age, needle size, and CSF pressure. RESULTS: Data from 112 patients were collected; PDPH was reported in 39 patients (34.8%), and 40 (35.7%) patients were admitted. The median (interquartile range) CSF RBC count was 10 [2-100.8] cells/µL. One-way analysis of variance test of the mean differences among the three groups showed no differences in age, the duration of headache before LP, PLT counts, PT, or aPTT among the groups. There were differences in the number of admitted patients (30 vs. 7 vs. 3, P < 0.001) and the incidence of PDPH (29 vs. 6 vs. 4, P < 0.003). In the comparison of the PDPH and non-PDPH groups, there were differences in age (28.7 ± 8.4 years vs. 36.9 ± 18.4 years, P = 0.01) and the admission rate (85% vs. 9%, P < 0.001). CONCLUSIONS: Notably, our results suggest that traumatic LP may be an unexpected factor in reducing the occurrence rate of PDPH. Consequently, the admission rate for PDPH was significantly reduced among patients with traumatic LP and those with primary headaches. In this study, we collected and analyzed the data from a relatively small sample size of 112 patients. Further studies are needed to evaluate the relationship between traumatic LP and PDPH.

The Impact of Omicron Wave on Pediatric Febrile Seizure.

BACKGROUND: The coronavirus disease 2019 (COVID-19) omicron (B.1.1.529) variant reduced the risk of severe disease compared with the original strain and other variants, but it appeared to be highly infectious, which resulted in an exponential increase in confirmed cases in South Korea. As the number of confirmed cases increased, so did the number of pediatric patients' hospitalization. This study aims to evaluate the frequency and clinical features of febrile seizure associated with the COVID-19 omicron variant in children. METHODS: We retrospectively reviewed the medical records of children aged under 18 years with febrile seizure who were tested for COVID-19 from February 2020 to April 2022 at Ajou University Hospital, South Korea. Based on the dominant variants, we divided the period into the pre-omicron (from February 2020 to December 2021) and omicron periods (from January 2022 to April 2022) and compared the clinical characteristics between the two. Also, we compared the clinical characteristics of febrile seizure between COVID-19 positive and negative group during the omicron period. RESULTS: Among the 308 children, 211 patients (9.2 patients/months) and 97 patients (24.3 patients/months) were grouped into pre-omicron and omicron periods, respectively. Compared with the pre-omicron period, patients in the omicron period showed significantly higher mean age (pre-omicron vs. omicron, 22.0 vs. 28.0 months; P = 0.004) and COVID-19 positive results (pre-omicron vs. omicron, 0.5% vs. 62.9%; P < 0.001). As the COVID-19 confirmed cases in the omicron period increased, the number of COVID-19 associated febrile seizure also increased. In the omicron period, 61 children were confirmed to be positive for COVID-19, and COVID-19 positive group showed statistically significant higher mean age (positive vs. negative, 33.0 vs. 23.0 months; P = 0.003) and peak body temperature than the negative group (positive vs. negative, 39.1°C vs. 38.6°C; P = 0.030). Despite the lack of significance, COVID-19 positive group showed longer seizure time, multiple seizure episodes, and higher prevalence of complex febrile seizure. CONCLUSION: The frequency of COVID-19 associated febrile seizure increased in the omicron periods. In addition, in this period, children with febrile seizure diagnosed with COVID-19 had a higher mean age and higher peak body temperature.

Age-Dependent Effects of COVID-19 Vaccine and of Healthcare Burden on COVID-19 Deaths, Tokyo, Japan.

COVID-19 vaccine effectiveness against death in Japan remains unknown. Furthermore, although evidence indicates that healthcare capacity influences case-fatality risk (CFR), it remains unknown whether this relationship is mediated by age. With a modeling study, we analyzed daily COVID-19 cases and deaths during January-August 2021 by using Tokyo surveillance data to jointly estimate COVID-19 vaccine effectiveness against death and age-specific CFR. We also examined daily healthcare operations to determine the association between healthcare burden and age-specific CFR. Among fully vaccinated patients, vaccine effectiveness against death was 88.6% among patients 60-69 years of age, 83.9% among patients 70-79 years of age, 83.5% among patients 80-89 years of age, and 77.7% among patients >90 years of age. A positive association of several indicators of healthcare burden with CFR among patients >70 years of age suggested an age-dependent effect of healthcare burden on CFR in Japan.

Comparison of the Clinical Characteristics of Pediatric Poisoning Patients Who Visited Emergency Department Before and During the COVID-19 Pandemic.

BACKGROUND: We aimed to investigate changes in the clinical characteristics of pediatric poisoning patients who visited the emergency department (ED) before and during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: Poisoning cases below age 18 who visited the ED from January 2018 to December 2021 were retrospectively analysed. The study period was then divided into pre-COVID-19 and COVID-19 pandemic to compare poisoning patterns. RESULTS: During the study period, 86,153 visits to the pediatric ED had been recorded, with 625 patients being included the final analysis. During the COVID-19 period, the proportion of poisoned patients increased from 0.62% to 0.98%. The average age of the patients was higher in the COVID-19 period, with 53.4% of the cases being intentional (pre-COVID-19, 32.5%; P < 0.001). Moreover, 70.4% of poisoning cases during the COVID-19 period were caused by drugs (pre-COVID-19, 60.6%; P = 0.038). More patients underwent decontamination and laboratory investigation during the COVID-19 period than during the previous period (P = 0.007 and P < 0.001, respectively). The length of ED stay and the proportion of hospitalisation were significantly greater during the COVID-19 period. After analysing accidental poisoning cases, we found that antipyretics/nonsteroidal anti-inflammatory drugs and respiratory drugs were more common in the pre-COVID-19 group, whereas iron/vitamins, cardiovascular drugs and hormones were more common in the COVID-19 group. After analysing intentional poisoning cases, we found that 73.6% and 76.4% of the patients in the pre-COVID-19 and COVID-19 group had a history of psychiatric disease, respectively. Although no difference was observed in the frequency of previous first suicide attempts, 19.0% of the patients in the COVID-19 group attempted suicide more than three times. CONCLUSION: During the COVID-19 pandemic, intentional poisoning cases, especially in adolescence, increased and were treated more. Many of the patients with intentional poisoning had a history of mental illness or suicide in the past. Therefore, it seems that policy consideration for mentally vulnerable adolescents during this new pandemic period is necessary.

Familial Clusters of Coronavirus Disease in 10 Prefectures, Japan, February-May 2020.

The overall coronavirus disease secondary attack rate (SAR) in family members was 19.0% in 10 prefectures of Japan during February 22-May 31, 2020. The SAR was lower for primary cases diagnosed early, within 2 days after symptom onset. The SAR of asymptomatic primary cases was 11.8%.

The effect of oral ondansetron on QT interval in children with acute gastroenteritis; a retrospective observational study.

BACKGROUND: In mildly to moderately dehydrated patients with acute gastroenteritis (AGE), oral rehydration therapy (ORT) is the treatment of choice. Though ondansetron is a very effective antiemetics and leads to succeed ORT, there have been reports QT prolongation in patients using it. We investigated the effect of oral ondansetron on QT interval in mildly to moderately dehydrated children with AGE. METHODS: This retrospective observational study was conducted in a single pediatric emergency department (ED) of a tertiary university hospital. We collected the medical records of patients with a primary diagnosis of AGE who received oral ondansetron and underwent an electrocardiogram between January 2017 and June 2018. A pediatric emergency physician calculated the corrected QT interval (QTc) by Bazett's method, and the calculations were reviewed by a pediatric cardiologist. QTc values before (preQTc) and after (postQTc) ondansetron administration were analyzed. ΔQTc was calculated as the change from preQTc to postQTc. We also investigated any cardiac complications from oral ondansetron. RESULTS: Total 80 patients were included. The mean age of the patients was 53.31 ± 32.42 months, and 45% were male. The mean dose of oral ondansetron was 0.18 ± 0.04 mg/kg. The mean interval from administration of ondansetron to performance of the electrocardiogram was 65 ± 26 min. The mean preQTc was 403.3 ± 24.0 ms, and the mean postQTc was 407.2 ± 26.7 ms. Two patients had a preQTc ≥460 ms, and one patient had a postQTc ≥460 ms. ΔQTc was ≥30 ms in seven patients (8.8%). No ΔQTc was ≥60 ms. No pre- or postQTc was ≥500 ms. No patient had a fatal cardiac arrhythmia after taking ondansetron. CONCLUSION: Oral administration of a single dose of ondansetron in children with AGE did not cause high-risk QTc prolongation or fatal arrhythmia.

Performance of the BIG Score in Predicting Mortality in Normotensive Children With Trauma.

OBJECTIVES: Children have a larger reserve for traumatic hemorrhagic shock, requiring a score that uses physiologic variables other than hypotension. Recently, the BIG score comprising admission base deficit, international normalized ratio, and the Glasgow Coma Scale has been reported to predict traumatic mortality. We aimed to validate the performance of the BIG score in mortality prediction of normotensive children with trauma. METHODS: We reviewed 1046 injured children (<18 years) who visited a Korean academic hospital from 2010 to 2018, excluding those with age-adjusted hypotension. In-hospital mortality, the BIG score and its predicted mortality, Revised Trauma Score, and Pediatric Trauma Score were calculated. We compared areas under the curve (AUCs) for in-hospital mortality of the 3 scores and did in-hospital and BIG-predicted mortalities. RESULTS: Of the 1046 children, 554 were enrolled with a 4.9% in-hospital mortality rate. The median BIG score was higher in the nonsurvivors (6.4 [interquartile range, 4.4-9.2] vs 20.1 [16.5-24.8]; P < 0.001). The AUC of the BIG score was 0.94 (95% confidence interval [CI], 0.92-0.96), which was higher than that of Pediatric Trauma Score (0.87 [95% CI, 0.84-0.90]; P < 0.001). The AUC of the BIG score tended to be higher than that of Revised Trauma Score without statistical significance (0.90 [95% CI, 0.87-0.92]; P = 0.130). We noted a parallel between in-hospital and BIG-predicted mortalities. The hemorrhage-related nonsurvivors showed higher median base deficit and BIG score than did the isolated traumatic brain injury-related ones. CONCLUSIONS: The BIG score can predict mortality with excellent accuracy in normotensive children with trauma.

Clusters of Coronavirus Disease in Communities, Japan, January-April 2020.

We analyzed 3,184 cases of coronavirus disease in Japan and identified 61 case-clusters in healthcare and other care facilities, restaurants and bars, workplaces, and music events. We also identified 22 probable primary case-patients for the clusters; most were 20-39 years of age and presymptomatic or asymptomatic at virus transmission.