A5006489248- SARS-CoV-2 and COVID-19 Research
- COVID-19 Clinical Research Studies
- Animal Virus Infections Studies
- SARS-CoV-2 detection and testing
- Influenza Virus Research Studies
- Respiratory viral infections research
- Viral Infections and Immunology Research
- Viral gastroenteritis research and epidemiology
- COVID-19 epidemiological studies
- COVID-19 Impact on Reproduction
- Vaccine Coverage and Hesitancy
- vaccines and immunoinformatics approaches
- Virus-based gene therapy research
- Immunotherapy and Immune Responses
- Long-Term Effects of COVID-19
- Animal Disease Management and Epidemiology
- Animal Diversity and Health Studies
- Acute Myocardial Infarction Research
- Infant Nutrition and Health
- Diabetes and associated disorders
- Infection Control and Ventilation
- Chronic Obstructive Pulmonary Disease (COPD) Research
- Heparin-Induced Thrombocytopenia and Thrombosis
- Bacterial Infections and Vaccines
- RNA and protein synthesis mechanisms
University of Hong Kong
2018-2025
Chinese University of Hong Kong
2020-2023
Hong Kong Science and Technology Parks Corporation
2021-2023
University of Hong Kong - Shenzhen Hospital
2023
HKU-Pasteur Research Pole
2021-2022
Kafrelsheikh University
2020
King Faisal University
2020
Nova Southeastern University
2012-2017
Liverpool Hospital
2012
UNSW Sydney
2009-2012
A novel coronavirus of zoonotic origin (2019-nCoV) has recently been identified in patients with acute respiratory disease. This virus is genetically similar to SARS and bat SARS-like coronaviruses. The outbreak was initially detected Wuhan, a major city China, but subsequently other provinces China. Travel-associated cases have also reported few countries. Outbreaks health care workers indicate human-to-human transmission. Molecular tests for rapid detection this are urgently needed early...
Abstract The SARS-CoV-2 pandemic poses the greatest global public health challenge in a century. Neutralizing antibody is correlate of protection and data on kinetics virus neutralizing responses are needed. We tested 293 sera from an observational cohort 195 reverse transcription polymerase chain reaction (RT-PCR) confirmed infections collected 0 to 209 days after onset symptoms. Of 115 ≥61 illness using plaque reduction neutralization (PRNT) assays, 99.1% remained seropositive for both 90%...
We investigated 68 respiratory specimens from 35 coronavirus disease patients in Hong Kong, of whom 32 had mild disease. found that severe acute syndrome 2 and subgenomic RNA were rarely detectable beyond 8 days after onset illness. However, virus was for many weeks by reverse transcription PCR.
The SARS-CoV-2 Omicron variant has demonstrated enhanced transmissibility and escape of vaccine-derived immunity. Although first-generation vaccines remain effective against severe disease death, robust evidence on vaccine effectiveness (VE) all infections, irrespective symptoms, remains sparse. We used a community-wide serosurvey with 5,310 subjects to estimate how vaccination histories modulated risk infection in infection-naive Hong Kong during large wave BA.2 epidemic January-July 2022....
Few head-to-head evaluations of immune responses to different vaccines have been reported.
SARS-CoV-2 infection of children leads to a mild illness and the immunological differences with adults are unclear. Here, we report specific T cell responses in infected find that acute memory CD4+ structural proteins increase age, whereas CD8+ time post-infection. Infected have lower ORF1ab when compared adults, comparable polyfunctionality reduced effector memory. Compared levels antibodies β-coronaviruses, indicating differing baseline immunity. Total follicular helper increased, whilst...
Surrogate neutralization assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that can be done without biosafety level 3 containment and in multiple species are desirable. We evaluate a recently developed surrogate virus test (sVNT) comparison to 90% plaque reduction tests (PRNT 90 ) human, canine, cat, hamster sera. With PRNT as the reference, sVNT had sensitivity of 98.9% specificity 98.8%. Using panel immune sera corresponding other coronaviruses, we confirm lack...
The duration of immunity in SARS-CoV-2 infected people remains unclear. Neutralizing antibody responses are the best available correlate protection against re-infection. Recent studies estimated that 50% from re-infection was 20% mean convalescent neutralizing titre.We collected sera a cohort 124 individuals with RT-PCR confirmed infections Prince Wales Hospital, Princess Margaret Queen Elizabeth Hospital and Mary Hospitals Authority Hong Kong, for periods up to 386 days after symptom onset...
We present an interim analysis of a registered clinical study (NCT04800133) to establish immunobridging with various antibody and cellular immunity markers compare the immunogenicity reactogenicity 2-dose BNT162b2 CoronaVac in healthy adolescents as primary objectives. One-dose BNT162b2, recommended some localities for risk reduction myocarditis, is also assessed. Antibodies T cell immune responses are non-inferior or similar receiving 2 doses (BB, N = 116) (CC, 123) versus adults after same...
The mRNA vaccine Comirnaty and the inactivated CoronaVac are both available in Hong Kong’s COVID-19 vaccination programme. We observed waning antibody levels 850 fully vaccinated (at least 14 days passed after second dose) blood donors using ELISA surrogate virus neutralisation test. Comirnaty-vaccinated group’s (n = 593) remained over sVNT positive cut-offs within first 6 months. CoronaVac-vaccinated 257) median began to fall below 4 months vaccination.
Abstract Viral and host factors can shape SARS-CoV-2 evolution. However, little is known about lineage-specific vaccination-specific mutations that occur within individuals. Here, we analysed deep sequencing data from 2,820 respiratory samples with different viral lineages to describe the patterns of within-host diversity under conditions, including vaccine-breakthrough infections. In unvaccinated individuals, variant Concern (VOC) Alpha, Delta, Omicron were found have higher neutral...
Hong Kong experienced a surge of Omicron BA.2 infections in early 2022, resulting one the highest per-capita death rates COVID-19. The outbreak occurred dense population with low immunity towards natural SARS-CoV-2 infection, high vaccine hesitancy vulnerable populations, comprehensive disease surveillance and capacity for stringent public health social measures (PHSMs). By analyzing genome sequences epidemiological data, we reconstructed epidemic trajectory wave found that initial community...
Abstract The high genetic diversity of influenza viruses means that traditional serological assays have too low throughput to measure serum antibody neutralization titers against all relevant strains. To overcome this challenge, we developed a sequencing-based assay simultaneously measures many viral strains using small volumes via workflow similar assays. key innovation is incorporate unique nucleotide barcodes into the hemagglutinin (HA) genomic segment, and then pool with numerous...
Abstract Since the emergence of SARS-CoV-2, different variants and subvariants successively emerged to dominate global virus circulation as a result immune evasion, replication fitness or both. COVID-19 vaccines continue be updated in response antigenically divergent viruses, first being bivalent RNA that encodes for both Wuhan-like Omicron BA.5 subvariant spike proteins. Repeated infections vaccine breakthrough have led complex landscapes populations making it increasingly difficult assess...
BackgroundOmicron subvariant BA.2 circulation is rapidly increasing globally.AimWe evaluated the neutralising antibody response from vaccination or prior SARS-CoV-2 infection against symptomatic by other variants.MethodsUsing 50% plaque reduction neutralisation tests (PRNT
Abstract The antibody response magnitude and kinetics may impact clinical severity, serological diagnosis long-term protection of COVID-19, which play a role in why children experience lower morbidity. We therefore tested samples from 122 Hong Kong with symptomatic ( n = 78) asymptomatic 44) SARS-CoV-2 infections up to 200 days post infection, relative 71 infected adults (symptomatic 61, 10), negative controls 48). assessed serum IgG antibodies 14-wide antigen panel structural accessory...
We detected high titers of cross-reactive neuraminidase inhibition antibodies to influenza A(H5N1) virus clade 2.3.4.4b in 96.8% (61/63) serum samples from healthy adults Hong Kong 2020. In contrast, at low were 42% (21/50) collected 2009. Influenza A(H1N1)pdm09 and correlated.
ABSTRACT The high genetic diversity of influenza viruses means that traditional serological assays have too low throughput to measure serum antibody neutralization titers against all relevant strains. To overcome this challenge, we developed a sequencing-based assay simultaneously measures many viral strains using small volumes workflow similar assays. key innovation is incorporate unique nucleotide barcodes into the hemagglutinin (HA) genomic segment, and then pool with numerous different...
In March 2020, mild signs and symptoms of coronavirus disease developed in a healthy 33-year-old man Hong Kong. His first infection did not produce virus neutralizing antibodies. August, he had asymptomatic reinfection, suggesting that persons without robust antibody response might be at risk for reinfection.
Zoonotic and pandemic influenza continue to pose threats global public health. Pandemics arise when novel A viruses, derived in whole or part from animal avian adapt transmit efficiently a human population that has little immunity contain its onward transmission. Viruses of previous concern, such as A(H7N9), arose A(H9N2) viruses established domestic poultry acquiring hemagglutinin neuraminidase aquatic waterfowl. We report A(H3N8) virus chicken emerged similar manner been recently reported...
Abstract Background The epidemiological advantage of Omicron variant is evidenced by its rapid spread and the ability to outcompete prior variants. Among sublineages, early outbreaks were dominated BA.1, while BA.2 has gained dominance since February 2022. relative pathogenicity transmissibility BA.1 have not been fully defined. Methods We compared viral loads clinical signs in Syrian hamsters after infection with BA.2, or D614G variant. A competitive transmission model next-generation...
Abstract Omicron, a novel SARS-CoV-2 variant has emerged and is rapidly becoming the dominant virus circulating globally. It important to define reductions in neutralizing activity serum of convalescent or vaccinated individuals understand potential loss protection from infection re-infection. Two doses BNT162b2 CoronaVac vaccines provided little 50% plaque reduction neutralization test (PRNT 50 ) antibody immunity against Omicron variant, even at one-month post vaccination. Booster with...