Background
Clinical management of shrimp allergy is hampered by the lack of accurate tests. Molecular diagnosis has been shown to more accurately reflect the clinical reactivity but the full spectrum ...of shrimp allergens and their clinical relevance are yet to be established. We therefore sought to comprehend the allergen repertoire of shrimp, investigate and compare the sensitization pattern and diagnostic value of the allergens in allergic subjects of two distinct populations.
Methods
Sera were collected from 85 subjects with challenge‐proven or doctor‐diagnosed shrimp allergy in Hong Kong and Thailand. The IgE‐binding proteins of Penaeus monodon were probed by Western blotting and identified by mass spectrometry. Recombinant shrimp allergens were synthesized and analyzed for IgE sensitization by ELISA.
Results
Ten IgE‐binding proteins were identified, and a comprehensive panel of 11 recombinant shrimp allergens was generated. The major shrimp allergens among Hong Kong subjects were troponin C (Pen m 6) and glycogen phosphorylase (Pen m 14, 47.1%), tropomyosin (Pen m 1, 41.2%) and sarcoplasmic‐calcium binding protein (Pen m 4, 35.3%), while those among Thai subjects were Pen m 1 (68.8%), Pen m 6 (50.0%) and fatty acid‐binding protein (Pen m 13, 37.5%). Component‐based tests yielded significantly higher area under curve values (0.77–0.96) than shrimp extract‐IgE test (0.70–0.75). Yet the best component test differed between populations; Pen m 1‐IgE test added diagnostic value only in the Thai cohort, whereas sensitizations to other components were better predictors of shrimp allergy in Hong Kong patients.
Conclusion
Pen m 14 was identified as a novel shrimp allergen predictive of challenge outcome. Molecular diagnosis better predicts shrimp allergy than conventional tests, but the relevant component is population dependent.
Glycogen phosphorylase (GP, Pen m 14) is identified as a new shrimp allergen. Troponin C (Pen m 6), fatty acid‐binding protein (Pen m 13) and Pen m 14 are major allergens apart from tropomyosin (Pen m 1) in shrimp allergic subjects from Hong Kong and Thailand. Molecular diagnostics better predicts shrimp allergy but relevant biomarker is population dependent.Abbreviations: AUC, area under curve; ELISA, enzyme‐linked immunosorbent assay; FABP, fatty acid‐binding protein; GP, glycogen phosphorylase; PSA, probably shrimp allergy; SPT, skin prick test; SDS‐PAGE, sodium dodecyl‐sulfate polyacrylamide gel electrophoresis; TM, tropomyosin; TnC, troponin C
Abstract
We present an interim analysis of a registered clinical study (NCT04800133) to establish immunobridging with various antibody and cellular immunity markers and to compare the immunogenicity ...and reactogenicity of 2-dose BNT162b2 and CoronaVac in healthy adolescents as primary objectives. One-dose BNT162b2, recommended in some localities for risk reduction of myocarditis, is also assessed. Antibodies and T cell immune responses are non-inferior or similar in adolescents receiving 2 doses of BNT162b2 (BB,
N
= 116) and CoronaVac (CC,
N
= 123) versus adults after 2 doses of the same vaccine (BB,
N
= 147; CC,
N
= 141) but not in adolescents after 1-dose BNT162b2 (B,
N
= 116). CC induces SARS-CoV-2 N and N C-terminal domain seropositivity in a higher proportion of adolescents than adults. Adverse reactions are mostly mild for both vaccines and more frequent for BNT162b2. We find higher S, neutralising, avidity and Fc receptor-binding antibody responses in adolescents receiving BB than CC, and a similar induction of strong S-specific T cells by the 2 vaccines, in addition to N- and M-specific T cells induced by CoronaVac but not BNT162b2, possibly implying differential durability and cross-variant protection by BNT162b2 and CoronaVac, the 2 most used SARS-CoV-2 vaccines worldwide. Our results support the use of both vaccines in adolescents.
Abstract
Background
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant BA.2 sublineage has increased rapidly in Europe and Asia since January 2022. Here, we report the ...epidemiological and genomic analysis of a large single-source BA.2 outbreak in a housing estate.
Methods
We analyzed the epidemiological information on a community outbreak of BA.2 (STY outbreak). We performed whole viral genome sequencing using the Oxford Nanopore MinION device. We calculated the doubling time of the outbreak within a housing estate.
Results
The STY outbreak involved a total of 768 individuals as of 5 February 2022, including 432 residents, visitors, or staff (56.3%) from a single housing estate (KC Estate). The outbreak at the KC Estate had a short doubling time of 1.28 days (95% confidence interval: .560–1.935). The outbreak was promptly controlled with the lockdown of 3 buildings within the housing estate. Whole-genome sequencing was performed for 133 patients in the STY outbreak, including 106 residents of the KC Estate. All 133 sequences from the STY outbreak belonged to the BA.2 sublineage, and phylogenetic analysis showed that these sequences cluster together. All individuals in the STY cluster had the unique mutation C12525T.
Conclusions
Our study highlights the exceptionally high transmissibility of the Omicron variant BA.2 sublineage in Hong Kong, where stringent measures are implemented as part of the elimination strategy. Continual genomic surveillance is crucial in monitoring the emergence of epidemiologically important Omicron sublineages.
Using epidemiological and whole viral genome data, we demonstrated a single-source outbreak of Omicron variant sublineage BA.2 with a short doubling time in Hong Kong. This study highlighted the high transmissibility of BA.2 despite stringent prevention measures.
Background
The coronavirus disease 2019 (COVID-19) pandemic is having a profound impact on the health and development of children worldwide. There is limited evidence on the impact of COVID-19 and ...its related school closures and disease-containment measures on the psychosocial wellbeing of children; little research has been done on the characteristics of vulnerable groups and factors that promote resilience.
Methods
We conducted a large-scale cross-sectional population study of Hong Kong families with children aged 2–12 years. Parents completed an online survey on family demographics, child psychosocial wellbeing, functioning and lifestyle habits, parent–child interactions, and parental stress during school closures due to COVID-19. We used simple and multiple linear regression analyses to explore factors associated with child psychosocial problems and parental stress during the pandemic.
Results
The study included 29,202 individual families; of which 12,163 had children aged 2–5 years and 17,029 had children aged 6–12 years. The risk of child psychosocial problems was higher in children with special educational needs, and/or acute or chronic disease, mothers with mental illness, single-parent families, and low-income families. Delayed bedtime and/or inadequate sleep or exercise duration, extended use of electronic devices were associated with significantly higher parental stress and more psychosocial problems among pre-schoolers.
Conclusions
This study identifies vulnerable groups of children and highlights the importance of strengthening family coherence, adequate sleep and exercise, and responsible use of electronic devices in promoting psychosocial wellbeing during the COVID-19 pandemic.
The novel SARS-CoV-2 Omicron variant may increase the risk of re-infection and vaccine breakthrough infections as it possesses key mutations in the spike protein that affect neutralizing antibody ...response. Most studies on neutralization susceptibility were conducted using specimens from adult COVID-19 patients or vaccine recipients. However, since the paediatric population has an antibody response to SARS-CoV-2 infection that is distinct from the adult population, it is critical to assess the neutralization susceptibility of pediatric serum specimens. This study compared the neutralization susceptibility of serum specimens collected from 49 individuals of <18 years old, including 34 adolescent BNT162b2 (Pfizer-BioNTech) vaccine recipients, and 15 recovered COVID-19 patients aged between 2 and 17. We demonstrated that only 38.2% of BNT162b2 vaccine recipients and 26.7% of recovered COVID-19 patients had their serum neutralization titre at or above the detection threshold in our live virus microneutralization assay. Furthermore, the neutralizing antibody titer against the Omicron variant was substantially lower than those against the ancestral virus or the Beta variant. Our results suggest that vaccine recipients and COVID-19 patients in the pediatric age group will likely be more susceptible to vaccine breakthrough infections or reinfections due to the Omicron variant than previous variants.
Age-specific incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination in Asia is lacking. This study aimed to study the clinical characteristics and incidence of ...acute myocarditis/pericarditis among Hong Kong adolescents following Comirnaty vaccination.
This is a population cohort study in Hong Kong that monitored adverse events following immunization through a pharmacovigilance system for coronavirus disease 2019 (COVID-19) vaccines. All adolescents aged between 12 and 17 years following Comirnaty vaccination were monitored under the COVID-19 vaccine adverse event response and evaluation program. The clinical characteristics and overall incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination were analyzed.
Between 14 June 2021 and 4 September 2021, 33 Chinese adolescents who developed acute myocarditis/pericarditis following Comirnaty vaccination were identified. In total, 29 (87.88%) were male and 4 (12.12%) were female, with a median age of 15.25 years. And 27 (81.82%) and 6 (18.18%) cases developed acute myocarditis/pericarditis after receiving the second and first dose, respectively. All cases are mild and required only conservative management. The overall incidence of acute myocarditis/pericarditis was 18.52 (95% confidence interval CI, 11.67-29.01) per 100 000 persons vaccinated. The incidence after the first and second doses were 3.37 (95% CI, 1.12-9.51) and 21.22 (95% CI, 13.78-32.28 per 100 000 persons vaccinated, respectively. Among male adolescents, the incidence after the first and second doses were 5.57 (95% CI, 2.38-12.53) and 37.32 (95% CI, 26.98-51.25) per 100 000 persons vaccinated.
There is a significant increase in the risk of acute myocarditis/pericarditis following Comirnaty vaccination among Chinese male adolescents, especially after the second dose.
Genetic deficiencies of early components of the classical complement activation pathway (especially C1q, r, s, and C4) are the strongest monogenic causal factors for the prototypic autoimmune disease ...systemic lupus erythematosus (SLE), but their prevalence is extremely rare. In contrast, isotype genetic deficiency of C4A and acquired deficiency of C1q by autoantibodies are frequent among patients with SLE. Here we review the genetic basis of complement deficiencies in autoimmune disease, discuss the complex genetic diversity seen in complement C4 and its association with autoimmune disease, provide guidance as to when clinicians should suspect and test for complement deficiencies, and outline the current understanding of the mechanisms relating complement deficiencies to autoimmunity. We focus primarily on SLE, as the role of complement in SLE is well-established, but will also discuss other informative diseases such as inflammatory arthritis and myositis.
•Complement plays a role in autoimmune disease as well as host defense.•We will discuss putative mechanisms by which complement contributes to autoimmunity.•The clinical history, physical exam, and laboratory findings seen in patients with complement deficiencies will be reviewed.•C1q and C4 are most strongly associated with autoimmune disease.•In addition to complement's role in SLE, this review will also address autoimmune myopathy, arthritis, and type I diabetes mellitus.
Atopic dermatitis (AD) is one of the main risk factors for infants in the development of food allergy. Oral immunotherapy (OIT) in early childhood has been found to be highly effective and safe in ...preschoolers with and without AD, especially in young infants. Delays in initiation of OIT in infants and children due to uncontrolled AD risk expansion of the number of foods children develop allergy to through unnecessary avoidance of multiple foods. Parents and caregivers may attribute eczema flares to OIT doses, which physicians usually ascribe to non-food triggers such as weather changes, psychological stress, and infection. There is a lack of published literature confirming OIT as a trigger of AD flares, and the degree to which OIT may be associated with AD flares needs to be further studied. We describe 8 case scenarios with varying degrees of AD flare before and during OIT. We propose management algorithms for children with preexisting concurrent AD and food allergy who are being considered for starting OIT and children with AD flares during OIT. Optimizing AD control strategies and providing adequate AD care education before starting OIT can reduce confusion for both parents and allergists if rashes arise during OIT, thus improving adherence to OIT.
Accruing evidence suggests an increased risk of myocarditis in adolescents from messenger RNA COVID-19 vaccines. However, other potential adverse events remain under-researched. We conducted a ...retrospective cohort study of adolescents aged 12-18 with a territory-wide electronic healthcare database of the Hong Kong population linked with population-based vaccination records and supplemented with age- and sex-specific population numbers. Two age- and sex-matched retrospective cohorts were formed to observe 28 days following the first and second doses of BNT162b2 and estimate the age- and sex-adjusted incidence rate ratios between the vaccinated and unvaccinated. Thirty AESIs adapted from the World Health Organization's Global Advisory Committee on Vaccine Safety were examined. Eventually, the first-dose cohort comprised 274,881 adolescents (50.25% received the first dose) and the second-dose cohort 237,964 (50.29% received the second dose). Ninety-four (34.2 per 100,000 persons) adolescents in the first-dose cohort and 130 (54.6 per 100,000 persons) in the second-dose cohort experienced ≥1 AESIs. There were no statistically significant differences in the risk of any AESI associated with BNT162b2 except myocarditis first-dose cohort: incidence rate ratio (IRR) = 9.15, 95% confidence interval (CI) 1.14-73.16; second-dose cohort: IRR = 29.61, 95% CI 4.04-217.07 and sleeping disturbances/disorders after the second dose (IRR = 2.06, 95% CI 1.01-4.24). Sensitivity analysis showed that, with myocarditis excluded as AESIs, no significantly elevated risk of AESIs as a composite outcome associated with vaccination was observed (P = 0.195). To conclude, the overall absolute risk of AESIs was low with no evidence of an increased risk of AESIs except myocarditis and sleeping disturbances/disorders.