Although airborne transmission has been considered as a possible route for the spread of SARS-CoV-2, the role that aerosols play in SARS-CoV-2 transmission is still controversial. This study evaluated the airborne transmission of SARS-CoV-2 in COVID-19 isolation wards at Prince of Wales Hospital in Hong Kong by both on-site sampling and numerical analysis. A total of 838 air samples and 1176 surface samples were collected, and SARS-CoV-2 RNA was detected using the RT-PCR method.
View Article and Find Full Text PDFAir and surface contamination of the SARS-CoV-2 have been reported by multiple studies. However, the evidence is limited for the change of environmental contamination of this virus in the surrounding of patients with COVID-19 at different time points during the course of disease and under different conditions of the patients. Therefore, this study aims to understand the risk factors associated with the appearance of SARS-CoV-2 through the period when the patients were staying in the isolation wards.
View Article and Find Full Text PDFBackground: Prior to this report, variants of concern for SARS-CoV-2 were only detected from imported cases in Hong Kong.
Objective: Multiple cases of SARS-CoV-2 lineage B.1.
Hong Kong employed a strategy of intermittent public health and social measures alongside increasingly stringent travel regulations to eliminate domestic SARS-CoV-2 transmission. By analyzing 1899 genome sequences (>18% of confirmed cases) from 23-January-2020 to 26-January-2021, we reveal the effects of fluctuating control measures on the evolution and epidemiology of SARS-CoV-2 lineages in Hong Kong. Despite numerous importations, only three introductions were responsible for 90% of locally-acquired cases.
View Article and Find Full Text PDFExpert Rev Mol Diagn
January 2022
Background: The import of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineage B.1.36.
View Article and Find Full Text PDFBackground: Combined nasal-and-throat swabs (CNTS) is less invasive and easy to execute. CNTS also induces lower risk to healthcare workers upon collection. However, there is a lack of data on viral load assessment for population-wide testing.
View Article and Find Full Text PDFWe sequenced 10% of imported severe acute respiratory syndrome coronavirus 2 infections detected in travelers to Hong Kong and revealed the genomic diversity of regions of origin, including lineages not previously reported from those countries. Our results suggest that international or regional travel hubs might be useful surveillance sites to monitor sequence diversity.
View Article and Find Full Text PDFBackground: A large cluster of 59 cases were linked to a single flight with 146 passengers from New Delhi to Hong Kong in April 2021. This outbreak coincided with early reports of exponential pandemic growth in New Delhi, which reached a peak of > 400 000 newly confirmed cases on 7 May 2021.
Methods: Epidemiological information including date of symptom onset, date of positive-sample detection and travel and contact history for individual cases from this flight were collected.
An active, territory-wide, CPE surveillance program implemented from 2011 showed increasing levels of carbapenemase-producing Enterobacteriaceae (CPE) isolates from patients in Hong Kong hospitals. The molecular epidemiology of 567 CPE from patients of three of seven public hospital clusters in Hong Kong are described. During a 7-year period, the incidence of CPE isolation increased from 0.
View Article and Find Full Text PDFDiagn Microbiol Infect Dis
December 2021
RT-PCR is the gold standard to detect SARS-CoV-2, however, its capacity is limited. We evaluated an automated antigen detection (AAD) test, Elecsys SARS-CoV-2 Antigen (Roche, Germany), for detecting SARS-CoV-2. We compared the limit of detection (LOD) between AAD test, rapid antigen detection (RAD) test; SARS-CoV-2 Rapid Antigen Test (SD Biosensor, Korea), and in-house RT-PCR test.
View Article and Find Full Text PDFUnlabelled: Hong Kong utilized an elimination strategy with intermittent use of public health and social measures and increasingly stringent travel regulations to control SARS-CoV-2 transmission. By analyzing >1700 genome sequences representing 17% of confirmed cases from 23-January-2020 to 26-January-2021, we reveal the effects of fluctuating control measures on the evolution and epidemiology of SARS-CoV-2 lineages in Hong Kong. Despite numerous importations, only three introductions were responsible for 90% of locally-acquired cases, two of which circulated cryptically for weeks while less stringent measures were in place.
View Article and Find Full Text PDFLancet Digit Health
June 2021
Background: Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis, which are typically transmitted via respiratory droplets, are leading causes of invasive diseases, including bacteraemic pneumonia and meningitis, and of secondary infections subsequent to post-viral respiratory disease. The aim of this study was to investigate the incidence of invasive disease due to these pathogens during the early months of the COVID-19 pandemic.
Methods: In this prospective analysis of surveillance data, laboratories in 26 countries and territories across six continents submitted data on cases of invasive disease due to S pneumoniae, H influenzae, and N meningitidis from Jan 1, 2018, to May, 31, 2020, as part of the Invasive Respiratory Infection Surveillance (IRIS) Initiative.
To investigate a superspreading event at a fitness center in Hong Kong, China, we used genomic sequencing to analyze 102 reverse transcription PCR-confirmed cases of severe acute respiratory syndrome coronavirus 2 infection. Our finding highlights the risk for virus transmission in confined spaces with poor ventilation and limited public health interventions.
View Article and Find Full Text PDFIn 2020, numerous fast-spreading severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have been reported. These variants had unusually high genetic changes in the spike (S) protein. In an attempt to understand the genetic background of SARS-CoV-2 viruses in Hong Kong, especially before vaccination, the purpose of this study is to summarize the S protein mutations detected among coronavirus disease 2019 (COVID-19) patients in Hong Kong in 2020.
View Article and Find Full Text PDFWe describe an introduction of clade GH severe acute respiratory syndrome coronavirus 2 causing a fourth wave of coronavirus disease in Hong Kong. The virus has an ORF3a-Q57H mutation, causing truncation of ORF3b. This virus evades induction of cytokine, chemokine, and interferon-stimulated gene expression in primary human respiratory cells.
View Article and Find Full Text PDFBackground & Aims: Rat hepatitis E virus (Orthohepevirus species C; HEV-C1) is an emerging cause of viral hepatitis in humans. HEV-C1 is divergent from other HEV variants infecting humans that belong to Orthohepevirus species A (HEV-A). This study assessed HEV-C1 antigenic divergence from HEV-A and investigated the impact of this divergence on infection susceptibility, serological test sensitivity, and vaccine efficacy.
View Article and Find Full Text PDFMicrobiol Resour Announc
January 2021
is an emerging human pathogen associated with multidrug resistance and nosocomial outbreaks. We report the draft genome sequences of 19 isolates that were associated with a cluster of cases in a hospital in Hong Kong.
View Article and Find Full Text PDFBackground: Currently, there are two rapid antigen detection (RAD) kits from the WHO Emergency Use List for detecting SARS-CoV-2.
Objective: The Panbio COVID-19 Ag Rapid Test Device was selected to evaluate the performance for detecting SARS-CoV-2.
Study Design: Analytical sensitivity for the detection of SARS-CoV-2 virus was determined by limit of detection (LOD) using RT-PCR as a reference method.
Background: Numerous rapid antigen detection (RAD) kits for diagnosing COVID-19 patients are available in the market recently.
Objective: To compare analytical sensitivity and clinical sensitivity for the three commercially available RAD kits.
Study Design: Analytical sensitivity for the detection of SARS-CoV-2 virus was determined by limit of detection (LOD) using RT-PCR as a reference method.
We recently reported a patient with coronavirus disease 2019 reinfection. Here, we show that serum neutralizing antibodies could be detected during the first episode but not at the presentation of the second episode. During reinfection, neutralizing antibodies and high avidity immunoglobulin G were found within 8 days after hospitalization, whereas immunoglobulin M response was absent.
View Article and Find Full Text PDFFour persons with severe acute respiratory syndrome coronavirus 2 infection had traveled on the same flight from Boston, Massachusetts, USA, to Hong Kong, China. Their virus genetic sequences are identical, unique, and belong to a clade not previously identified in Hong Kong, which strongly suggests that the virus can be transmitted during air travel.
View Article and Find Full Text PDFClin Infect Dis
November 2021
Background: Waning immunity occurs in patients who have recovered from Coronavirus Disease 2019 (COVID-19). However, it remains unclear whether true re-infection occurs.
Methods: Whole genome sequencing was performed directly on respiratory specimens collected during 2 episodes of COVID-19 in a patient.
Infection risks of handling specimens associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by public health laboratory services teams were assessed to scrutinize the potential hazards arising from the work procedures. Through risk assessments of all work sequences, laboratory equipment, and workplace environments, no aerosol-generating procedures could be identified except the procedures (mixing and transfer steps) inside biological safety cabinets. Appropriate personal protective equipment (PPE) such as surgical masks, protective gowns, face shields/safety goggles, and disposable gloves, together with pertinent safety training, was provided for laboratory work.
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