[Diagnostic value of rapid antigen testing for the detection of SARS-CoV-2 infection].

Objective: To investigate the diagnostic value of rapid antigen test based on colloidal gold immunochromatographic assay for the detection of SARS-CoV-2 infection in symptomatic patients. Methods: From May 20 to June 5 2022, 76 hospitalized children and their 55 accompanying family members with confirmed SARS-CoV-2 infection in the COVID-19 isolation unit of the Children's Hospital of Fudan University (designated referral hospital for SARS-CoV-2 infection in Shanghai) enrolled. Their nasopharyngeal swab specimens were consecutively collected. The samples were tested for SARS-CoV-2 nucleic acid by real-time quantitative. SARS-CoV-2 antigen was tested by immunochromatography. The correlation between the antigen detection results and the change of the cycle threshold (Ct) values were evaluated, as well as the sensitivity and specificity of SARS-CoV-2 antigen detection at different periods after the onset of the disease. Kappa consistency test was conducted to investigate the consistency between the 2 diagnostic methods. Results: Of the enrolled SARS-CoV-2 symptomatic infections, 76 were children, including 41 males and 35 females, with an age of 5 (2, 9) years; 55 were accompanying families, including 8 males and 47 females, with an age of 38 (32, 41) years. All 478 samples were simultaneously tested for SARS-CoV-2 antigen and nucleic acid. In any period from disease onset to negative conversion of viral nucleic acid, the overall sensitivity of the rapid antigen test was 48.2% (119/247), the specificity was 98.3% (227/231), and antigen test and nucleic acid test showed moderate consistency (κ=0.46, P<0.05). The sensitivity of antigen test was 100% (82/82) when the Ct value was ≤25. And the sensitivity of antigen test was 8/10, 4/15 and 8.3% (3/36) when the Ct value was 26, 30 and 35, respectively. All antigen tests were negative when Ct value was >35. During the period of 1-2 days, 3-5 days, 6-7 days, 8-10 days and >10 days after onset, the sensitivity and specificity of SARS-CoV-2 antigen test were 5/8 and 5/5, 90.2% (37/41) and 5/5, 88.9% (24/27) and 2/5, 45.0% (36/80) and 94.1% (32/34), 18.7% (17/91) and 98.9% (183/185) respectively. The Ct values of nasopharyngeal swabs were<26 during 2 to 7 days after onset, 28.7±5.0 on day 8, 34.5±2.9 on day 13 and > 35 after 14 days, respectively. Conclusion: SARS-CoV-2 antigen test in the patients with SARS-CoV-2 infection shows acceptable sensitivity and specificity within 7 days after onset of disease, and the sensitivity was positively correlated with viral load and negatively correlated with onset time.

[Clinical characteristics of 16 neonates infected with SARS-CoV-2 during Omicron variant outbreak].

Objective: To analyze the clinical characteristics of the neonates infected with SARS-CoV-2 during the Omicron outbreak in Shanghai 2022. Methods: In this retrospective case series study, all the 16 neonates with SARS-CoV-2 Omicron infection who were admitted to the neonatal unit in Shanghai Public Health Clinical Center from March 1st to May 31st, 2022 were enrolled. Their epidemiological history, clinical manifestations, nucleic acid cycle threshold (Ct) value and outcomes were analyzed. Based on maternal vaccination, they were divided into vaccinated group and unvaccinated group. Rank sum test and Chi-square test were used for the comparison between the groups. Results: Among the 16 neonates, 10 were male, and 6 were female. All the infants were full-term. The infection was confirmed at the age of 12.5 (8.0, 20.5) days. All the neonates had a history of exposure to infected family members, and thus horizontal transmission was the primary mode. Four infants were asymptomatic, 12 were symptomatic, and there were no severe or critical cases. The most common clinical manifestation was fever (11 cases), with the highest temperature of 38.1 (37.9, 38.3) ℃ and a course of 1-5 days. Other clinical manifestations included nasal obstruction (3 cases), runny nose (2 cases), cough (2 cases), poor feeding (2 cases), vomiting (1 case), and mild tachypnea (1 case). The complete blood counts of all neonates were within the normal range, and the C-reactive protein increased slightly in 1 infant. Chest imaging was performed in 2 infants, showing mild focal exudative changes. Nucleic acid turned negative (Ct value ≥35) within 7-15 days after diagnosis. All neonates fully recovered after supportive treatment, and the length of hospitalization was 13 (10, 14) days. In the telephone follow-up 2 weeks after discharge for all 16 cases, no infant showed reoccurrence of clinical manifestations or nucleic acid reactivation. Maternal vaccination was not significantly correlated with symptomatic infection or the persistence of positive nucleic acid result in neonates (all P>0.05). Conclusions: Horizontal transmission is the primary mode for neonatal SARS-CoV-2 Omicron infection. Neonatal infections are usually mild or asymptomatic, with good short-term outcomes. And their clinical manifestations and laboratory examinations are nonspecific.

[Management and short-term outcomes of neonates born to mothers infected with SARS-CoV-2 Omicron variant].

Objective: To summarize the management and short-term outcomes of neonates delivered by mothers infected with SARS-CoV-2 Omicron variant. Methods: A retrospective study was performed on 158 neonates born to mothers infected with SARS-CoV-2 Omicron variant admitted to the isolation ward of Children's Hospital of Fudan University from March 15th, 2022 to May 30th, 2022. The postnatal infection control measures for these neonates, and their clinical characteristics and short-term outcomes were analyzed. They were divided into maternal symptomatic group and maternal asymptomatic group according to whether their mothers had SARS-CoV-2 symptoms. The clinical outcomes were compared between the 2 groups using Rank sum test and Chi-square test. Results: All neonates were under strict infection control measures at birth and after birth. Of the 158 neonates, 75 (47.5%) were male. The gestational age was (38+3±1+3) weeks and the birth weight was (3 201±463)g. Of the neonates included, ten were preterm (6.3%) and the minimum gestational age was 30+1 weeks. Six neonates (3.8%) had respiratory difficulty and 4 of them were premature and required mechanical ventilation. All 158 neonates were tested negative for SARS-COV-2 nucleic acid by daily nasal swabs for the first 7 days. A total of 156 mothers (2 cases of twin pregnancy) infected with SARS-CoV-2 Omicron variant, the time from confirmed SARS-CoV-2 infection to delivery was 7 (3, 12) days. Among them, 88 cases (56.4%) showed clinical symptoms, but none needed intensive care treatment. The peripheral white blood cell count of the neonates in maternal symptomatic group was significantly higher than that in maternal symptomatic group (23.0 (18.7, 28.0) × 109 vs. 19.6 (15.4, 36.6) × 109/L, Z=2.44, P<0.05). Conclusions: Neonates of mothers infected with SARS-CoV-2 Omicron variant during third trimester have benign short-term outcomes, without intrauterine infection through vertical transmission. Strict infection control measures at birth and after birth can effectively protect these neonates from SARS-CoV-2 infection.

Safety and efficacy of oral lopinavir/ritonavir in pediatric patients with coronavirus disease: a nationwide comparative analysis.

OBJECTIVE: Because of the limited treatment options available, oral lopinavir/ritonavir (LPR) was used for treating coronavirus disease (COVID-19) in pediatric patients. This study aimed to assess the efficacy and safety of LPR in COVID-19 pediatric patients with mild symptoms. PATIENTS AND METHODS: This retrospective multicenter analysis included hospitalized children with mild COVID-19 who received LPR at one of 13 hospitals in China from January 1, 2020, to June 1, 2020. Patients treated with LPR were matched with patients not treated with LPR (1:4) according to age, sex, and length of symptom onset and hospitalization. Descriptive statistics and non-parametric tests were applied to compare differences between groups. Kaplan-Meier probability curves and Cox regression models were used to analyze nasal swab turning negative time (recovery time) and hospital discharge days. RESULTS: In total, 23 patients treated with LPR were matched with 92 untreated controls. The median age of patients was 6 years, and 56.52% of them were male. All patients were discharged from the hospital after being cured. The treatment group had a longer nasal swab turning negative time (hazard ratio [HR] 5.33; 95% CI: 1.94-14.67; p = 0.001) than the control group. LPR treatment was also associated with a longer hospitalization time (HR 2.01; 95% CI: 1.24-3.29; p = 0.005). After adjusting for the influence of LPR treatment, adverse drug reaction events were associated with a longer nasopharyngeal swab negative time (HR 4.67; 95% CI 1.35-16.11; p = 0.015). CONCLUSIONS: For children with mild COVID-19, LPR is inferior to conventional treatment in reducing virus shedding time and hospitalization duration and is associated with increased adverse reactions.

China's experience in COVID-19 prevention and control among children in its different regions.

OBJECTIVE: To summarize the experience of three Chinese cities (Wuhan, Shanghai and Haikou) and provide a reference for global efforts to combat COVID-19 spread among children. MATERIALS AND METHODS: Through collecting the measures and outcomes of preventing and controlling COVID-19 in China's three hospitals, we compared the effect of different strategies. RESULTS: From January to March 2020, the number of suspected and confirmed COVID-19 cases in Wuhan increased exponentially, and Wuhan Children's Hospital as a whole was transformed into a designated quarantine and treatment facility, which is the "Wuhan Model". Shanghai has more children's hospitals with better capabilities to tackle public health emergency. Besides, it is far away from Wuhan and had a small caseload. Children's Hospital of Fudan University, a facility in Shanghai to treat pediatric infectious diseases, is famous for its well-equipped building for infectious disease treatment and professional medical team, and therefore no major transformation was required. That is the "Shanghai Model". Haikou is located on an island. Amid the outbreak, large numbers of tourists and travelers from Hubei had already arrived in Haikou. Hainan Women and Children's Medical Center, as the only pediatric care hospital in Hainan Province, did not have a separate building for infectious disease treatment. After a citywide survey of the medical resources and facilities available, a temporarily idle hospital 3 kilometers away from Hainan Women and Children's Medical Center was requisitioned as the quarantine and treatment facility for pediatric cases. That is the "Hainan Model". The three models enabled the treatment of all suspected and confirmed cases and no fatality was reported. CONCLUSIONS: The COVID-19 coping strategies for children should be designed according to the existing conditions of the local children's hospitals and the risk levels of the epidemic.

Screening process and management strategy of COVID-19 for outpaitent and emergency department in children's hospital

Since the occurrence of coronavirus disease 2019 (COVID-19) in Wuhan, Hubei Province of China in December 2019, the epidemic has developed rapidly and has now spread to the whole country. The pediatric hospital affiliated to Fudan University, as a designated hospital for treating children with infectious diseases in Shanghai, must be responsible for the treatment in children. The standardized hospital outpatient screening process management can improve the efficiency of diagnosis and treatment, reduce nosocomial infection, and control the spread of the epidemic. In order to deal with the epidemic situation, we carefully studied a series of laws and regulations, as well as instructions documents issued by the National Health and Health Commission, we reviewed and referenced recently published domestic and foreign literature, we also combined with the characteristics of children's specialist hospital, then formulated this screening process and management strategy of COVID-19 in outpatient and emergency departments. © 2020, Editorial Department of Fudan University Journal of Medical Sciences. All right reserved.