Clinical Characteristics and Transmission of COVID-19 in Children and Youths During 3 Waves of Outbreaks in Hong Kong

IMPORTANCE: Schools were closed intermittently across Hong Kong to control the COVID-19 outbreak, which led to significant physical and psychosocial problems among children and youths. OBJECTIVE: To compare the clinical characteristics and sources of infection among children and youths with COVID-19 during the 3 waves of outbreaks in Hong Kong in 2020. DESIGN, SETTING AND PARTICIPANTS: This cross-sectional study involved children and youths aged 18 years or younger with COVID-19 in the 3 waves of outbreaks from January 23 through December 2, 2020. Data were analyzed from December 2020 through January 2021. MAIN OUTCOMES AND MEASURES: Demographic characteristics, travel and contact histories, lengths of hospital stay, and symptoms were captured through the central electronic database. Individuals who were infected without recent international travel were defined as having domestic infections. RESULTS: Among 397 children and youths confirmed with COVID-19 infections, the mean (SD) age was 9.95 (5.34) years, 220 individuals (55.4%) were male, and 154 individuals (38.8%) were asymptomatic. There were significantly more individuals who were infected without symptoms in the second wave (59 of 118 individuals [50.0%]) and third wave (94 of 265 individuals [35.5%]) than in the first wave (1 of 14 individuals [7.1%]) (P = .001). Significantly fewer individuals who were infected in the second and third waves, compared with the first wave, had fever (first wave: 10 individuals [71.4%]; second wave: 22 individuals [18.5%]; third wave: 98 individuals [37.0%]; P < .001) or cough (first wave: 6 individuals [42.9%]; second wave: 15 individuals [12.7%]; third wave: 52 individuals [19.6%]; P = .02). Among all individuals, 394 individuals (99.2%) had mild illness. One patient developed chilblains (ie, COVID toes), 1 patient developed multisystem inflammatory syndrome in children, and 1 patient developed post–COVID-19 autoimmune hemolytic anemia. In all 3 waves, 204 patients with COVID-19 (51.4%) had domestic infections. Among these individuals, 186 (91.2%) reported having a contact history with another individual with COVID-19, of which most (183 individuals [90.0%]) were family members. In the third wave, 18 individuals with domestic infections had unknown contact histories. Three schoolmates were confirmed with COVID-19 on the same day and were reported to be close contacts. CONCLUSIONS AND RELEVANCE: his cross-sectional study found that nearly all children and youths with COVID-19 in Hong Kong had mild illness. These findings suggest that household transmission was the main source of infection for children and youths with domestic infections and that the risk of being infected at school was small

Diagnosing acute appendicitis: are we overusing radiologic investigations?

Purpose: Acute appendicitis is the most common emergency presenting to pediatric surgeons. With proper history and thorough physical examination, the diagnosis of the condition clinically should approach 90%. With the increasing ease of performing radiologic investigations because of technological advances, more ultrasound and computed tomography (CT) are used to help diagnosing appendicitis. The aim of this study is to review the trend of diagnosing appendicitis in a single center and discuss the implications. Methods: A retrospective analysis was carried out for all patients who were admitted with acute appendicitis between 1997 and 2007. The methods of diagnosis were divided into 3 groups as follows: clinical, ultrasound, and CT. The demographics and operative findings were noted. Statistical analysis was done using Fisher's Exact test and paired t test when appropriate. A value of P < .05 was considered to be statistically significant. Results: During this period, a total of 254 patients (167 boys and 87 girls) were admitted with appendicitis. The average age at presentation was 12 years, and the mean duration of symptoms before presentation was 2 days. For 11 years, there was an initial rise of the use of ultrasound (10% in 1997 to a peak of 60% in 2005). This percentage decreased with a corresponding rise of the use of CT scan (0% in 1997 to 35% in 2007). There was no correlation found between the use of adjunct investigations and the severity of appendicitis found at operation, suggesting an overreliance of CT. Conclusion: It appears that there is an increasing trend in using radiologic investigations for the diagnosis of appendicitis for the past 11 years. With the association of cancer in later life and early radiation exposure well documented, it would be advisable to avoid the use of CT if possible. © 2008 Elsevier Inc. All rights reserved.link_to_subscribed_fulltex

Removal of pyrene from contaminated sediments by mangrove microcosms

The potential of mangrove wetland systems to remove pyrene from surface- or bottom-contaminated sediments was investigated by microcosm studies. The performance of two mangrove plant species, Kandelia candel and Bruguiera gymnorrhiza in pyrene removal was also compared. During the six-months experimental period, the growth of both species in the surface-contaminated microcosms was not significantly different from that in the bottom-contaminated ones, and was comparable to the control (without any pyrene contamination). At the end of six-months treatment, pyrene concentrations in contaminated sediments declined from an initial 3 μg g -1 to less than 0.4 μg g -1, indicating that pyrene was successfully removed by mangrove microcosms. Around 96.4% and 92.8% pyrene in microcosms planted with K. candel were removed from the surface- and bottom-contaminated sediments, respectively. The removal percentages were slightly lower in microcosms planted with B. gymnorrhiza. Significant accumulation of pyrene in roots was only found in microcosms having bottom-contaminated sediments, and pyrene concentrations were 3.05 μg g -1 and 4.50 μg g -1 in roots of K. candel and B. gymnorrhiza, respectively. These values were much higher than that in control microcosms (without pyrene contamination, root pyrene concentrations were 0.27 μg g -1 for K candel and 0.34 μg g -1 for B. gymnorrhiza) and in microcosms with contaminated sediments placed at the surface layer. Nevertheless, the overall contribution of root accumulation and plant uptake to the removal of pyrene from contaminated sediments was insignificant. © 2003 Elsevier Science Ltd. All rights reserved

The Endocrine Disruptor Perflurooctane Sulfonate (PFOS) modulates spheroids attachment onto endometrial cells through Wnt/β -catenin Inhibition

Poster Presentation: Theme 2: Cancer & Cell Biology: no. 2.2

Relationship between anti-Mullerian hormone, obesity and insulin resistance in women with polycystic ovary syndrome

Conference Theme: Towards Safer, More Successful AR