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@#navirus disease 2019 (COVID-19) in the patients younger than 18 years old infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, and to provide a basis for determining the chest CT changes and efficacy of COVID-19 caused by Omicron virus variant in patients younger than 18 years old. Methods The clinical and imaging data of 30 cases of patients younger than 18 years old infected with COVID-19 Omicron variant, who admitted to the Third People's Hospital of Shenzhen from February 11 to March 26, 2022 were collected and retrospectively analyzed. The clinical manifestations, imaging features and dynamic changes of lesions were summarized. Results A total of 41 intrapulmonary lesions in 30 patients with COVID-19 caused by SARS-CoV-2 Omicron variant. The main manifestations were patchy or nodular ground-glass opacities and/or consolidation, with focal subpleural distribution, lesions mainly occur in the right lung (70.73%, 29/41). There were 42 lesion morphologies, with 22 (52.38%) striped shadows and 16 (38.10%) nodular shadows, with small lamellar and patchy shadows predominating. There were 36 lesion density variations, with ground glass shadows being the most common, with a total of 24 ground glass shadows (66.66%) in each lobe of the lung, and also 6 consolidation lesions (16.67%) and 6 mixed ground glass opacity and consolidation lesions (16.67%). With the progression of the disease, lesions gradually enlarged, appeared on the 2nd day (312.93 mm3), peaked on the 9th day (1 837.18 mm3). The average absorption time of the lesions was (16±3) days, and there was no significant difference between the absorption time of patchy and nodular lesions (ground glass and/or consolidation) (t=0.853, P>0.05). The lesions showed focal ground-glass opacity in the early stage, 77.78% lesions were absorbed after treatment in the late stage. Inflammatory nodules were absorbed slowly (9-19 days), without residual fibrotic changes. Conclusions The imaging manifestations of COVID-19 in patients younger than 18 years old infected with SARS-CoV-2 Omicron variant have certain characteristics, showed patchy or nodular ground glass opacities and/or consolidation, mainly distributed in the subpleural area, with small and few lesions and slow change, didn't remain fibrosis. Being familiar with its clinical and imaging manifestations can assist in early diagnosis, but confirming the diagnosis requires a combination of epidemiological history, clinical symptoms, SARS-CoV-2 nucleic acid and radiological manifestations.
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@#Objective To develop and verify an indirect ELISA method for determination of specific IgG antibody of rhesus monkey serum against SARS-CoV-2 variant strain. Methods An indirect ELISA method for the determination of specific IgG antibody was developed using inactivated SARS-CoV-2 Beta variant strain inactivated vaccine as coating antigen,and optimized for the coating antigen concentration(1,2 and 4 μg/mL),dilution of serum(1∶800～1∶12 800),blocking solution(PBST containing 1% BSA,2% BSA,1% skim milk,2% skim milk and 1% BSA + 1% skim milk),blocking time(30,60 and 90 min),dilution of secondary antibody(1∶5 000,1∶10 000,1∶15 000 and 1∶20 000),incubation time of serum and secondary antibody(30,60 and 90 min),and TMB reaction time(5,10,15,20,25 and 30 min). 60 negative serum samples of rhesus monkeys were detected by the developed method,and the negative and positive critical values were determined. The sensitivity and precision of the methodology were verified. In addition,the specific IgG antibody and neutralizing antibody against SARS-CoV-2 Beta variant strain in 44 serum samples of rhesus monkey were detected by the developed method and microneutralization method,and the correlation and consistency between the two methods were compared. Results The optimum detection conditions were determined:the coating antigen concentration was 1 μg/mL;the blocking solution was PBST containing 1% skim milk,and the blocking time was 30 min;the serum samples to be tested were diluted to 1∶1 600 and incubated for 90 min,and the secondary antibody was diluted to 1∶10 000 and incubated for 30 min;the color development time of substrate was 25 min. The positive critical value and negative critical value of the method was 0. 093 and 0. 084 respectively,and the detection values between them were judged as suspicious. The dilution of5 positive serum samples that showed positive results was 1∶51 200;the coefficients of variation(CVs)of precision were all less than 15%. There was a strong correlation between IgG antibody titer and neutralizing antibody level in the 44 rhesus monkey serum samples(r = 0. 858 0,P < 0. 000 1);the total coincidence rate of the two methods was 90. 9%,the positive coincidence rate was 93. 6%,and the negative coincidence rate was 84. 6%;the consistency test Kappa value was 0. 783 8(95% CI:0. 586 5～0. 981 0). Conclusion The developed indirect ELISA method for eletermination of specific IgG antibody against SARS-CoV-2 Beta variant strain in rhesus monkey serum has good sensitivity and precision,and has strong consistency with microneutralization method,which can be used for the determination of IgG antibody in rhesus monkey serum.
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Background: The incidence of breakthrough infection with the emergence of new variants of concern of SARS?CoV?2 is posing a threat, and it is pertinent to understand the role of vaccines in protecting the elderly and people with comorbidities. Objective: The present study was undertaken to understand the natural history of SARS?CoV?2 infection in a closed cohort of the elderly population in an old?age home who have received two doses of COVID?19 vaccination. The study has also undertaken genomic sequencing to identify SARS?CoV?2 variants of concern from an academic perspective. Materials and Methods: A prospective observational study was conducted from March to August 2021 among residents of 11 old?age homes in Kerala who were vaccinated with 2 doses of the COVID?19 vaccine, from 2 weeks following vaccination. Samples with a threshold cycle value of <25 were subjected to targeted sequencing of the spike protein receptor?binding domain coding region. Results: Among the 479 vaccinated individuals, 86 (17.95%) turned positive during the follow?up period. The mean duration of symptoms was 3–5 days, and no hospitalization was required. A phylogenetic analysis of the nucleotide sequences from the samples indicated B.1.617.2 lineage representing the Delta strain. Conclusion: The evidence supports maximizing the vaccine coverage among vulnerable groups to prevent hospitalization and death rate on the verge of the emergence of new variants of SARS?CoV?2.
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Background: Fungal colonisation of airways in Post TB patients, can lead to a spectrum of diseases based on the immune response of the host. This study was aimed at studying the different entities of this spectrum. Methods: A cross sectional observational study was conducted over 100 patients of post TB patients to make an observation of the diseases of the spectrum of Aspergillus infections. Results: Of the 100 patients who were studied, IPA was found in 24 (48%), ABPA in 13 (26%), CPA in 5 (10%) patients out of the 50 diabetics. ABPA in 23 (46%) patients, Simple colonization, CPA in 11 (22%) and 4 (8%) patients showed IPA out of the 50 non-diabetics. Conclusion: Chronic pulmonary Aspergillosis was the most common disease from Aspergillus among Post TB patients. Diabetes was associated with invasive forms of Aspergillosis, Invasive Pulmonary Aspergillosis (IPA) and subacute invasive pulmonary aspergillosis (SAIA).
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ABSTRACT Herein we describe a mild symptomatic real-time reverse transcriptase- polymerase chain reaction-confirmed coronavirus 2 (SARS-CoV-2) infection in a pregnant woman who gave birth to a preterm infant, 32 weeks gestational age. The neonate was immediately isolated after delivery and developed severe respiratory disease that progressed to multisystem inflammatory syndrome and death on the seventh day of life. Genome sequencing detected the P.1 (gamma) variant in samples obtained at hospital admission (mother) and on the first (10h) and 13th days of life (neonate). Complete homology (mother's and newborn's sequences) confirmed vertical transmission. To our knowledge, this is the first report of vertically-transmitted SARS-CoV-2 P.1 (gamma) variant in a mild symptomatic infection in pregnancy associated with fatal COVID in a neonate.