Evolution and Control of COVID-19 Epidemic in Hong Kong

Abstract

Hong Kong SAR has adopted universal masking, social distancing, testing of all symptomatic and high-risk groups for isolation of confirmed cases in healthcare facilities, and quarantine of contacts as epidemiological control measures without city lockdown or border closure. These measures successfully suppressed the community transmission of pre-Omicron SARS-CoV-2 variants or lineages during the first to the fourth wave. No nosocomial SARS-CoV-2 infection was documented among healthcare workers in the first 300 days. The strategy of COVID-19 containment was adopted to provide additional time to achieve population immunity by vaccination. The near-zero COVID-19 situation for about 8 months in 2021 did not enable adequate immunization of the eligible population. A combination of factors was identified, especially population complacency associated with the low local COVID-19 activity, together with vaccine hesitancy. The importation of the highly transmissible Omicron variant kickstarted the fifth wave of COVID-19, which could no longer be controlled by our initial measures. The explosive fifth wave, which was partially contributed to by vertical airborne transmission in high-rise residential buildings, resulted in over one million cases of infection. In this review, we summarize the epidemiology of COVID-19 and the infection control and public health measures against the importation and dissemination of SARS-CoV-2 until day 1000.

Real-World Study on Effectiveness of Molnupiravir and Nirmatrelvir–Ritonavir in Unvaccinated Patients with Chronic Respiratory Diseases with Confirmed SARS-CoV-2 Infection Managed in Out-Patient Setting

“…In Hong Kong, the uptake of COVID-19 vaccine among the elderly population was poor. By the end of February 2022, the proportions of the unvaccinated Hong Kong population aged over 60 years and aged over 80 years were 26% and 50%, respectively [ 28 ]. These were 64% and 59% of the subjects within our cohort above the age of 60 years and 80 years, respectively.…”

Epidemiology of multidrug-resistant organisms before and during COVID-19 in Hong Kong

“…There are several limitations in this study. First, this study ended early in September 2022 rather than in December 2022 because we needed to cover the first 1000 days of COVID-19 combat in Hong Kong, as hospital services gradually resume normalcy after day 1000 [ 57 ]. Second, we only included MRSA, CRA, and ESBL-producing Enterobacterales as the representative MDROs, excluding VRE and carbapenemase-producing Enterobacterales (CPE).…”

Intranasal Boosting with Spike Fc-RBD of Wild-Type SARS-CoV-2 Induces Neutralizing Antibodies against Omicron Subvariants and Reduces Viral Load in the Nasal Turbinate of Mice

“…The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over 600 million people and caused over 6 million deaths after 3 years [ 1 ]. While social distancing, universal masking, screening by rapid diagnostic tests, isolation of test-positive cases, quarantine of contacts, and early treatment of cases with risk factors by antivirals or neutralizing antibodies are the key control measures in the early phase of the pandemic, vaccination has become critical for converting this pandemic disease into an endemic disease [ 2 , 3 , 4 ]. Although the presently available COVID-19 vaccines mainly prevent severe disease and cannot completely stop infection, the hybrid immunity generated by these vaccines together with natural infection may be sufficient for the vaccinated population to live at pre-pandemic normalcy [ 5 ].…”