In the first 2 years of the COVID-19 pandemic, Hong Kong adopted strict public health and social measures to stop community transmission of SARS-CoV-2. These include border screening and control, isolation of cases and quarantine of their contacts and universal masking. During this period, attack rates in Hong Kong were among the lowest globally.
To estimate the seroprevalence of COVID-19 among healthcare workers (HCWs) in Hong Kong in 2020 and 2021.
We reviewed contact tracing data from the Hong Kong Department of Health to identify COVID-19 cases reported among HCWs. Between June 2020 and December 2021, we conducted a longitudinal cohort study to estimate the seroprevalence of COVID-19 among HCWs working in hospitals and clinics in Hong Kong during the first 2 years of the COVID-19 pandemic.
Overall seropositivity of COVID-19 by plaque reduction neutralisation test during the first (May–October 2020) and second round (November 2020–April 2021) of the study was 0% (95% CI 0.00% to 0.49%) and 0.52% (95% CI 0.14% to 1.33%). After COVID-19 vaccines were offered to HCWs in February 2021, seroprevalence by surrogate virus neutralisation assay among cohort participants who provided biannual blood samples rose to 68.7% (95% CI 65.9%, 71.3%) and 80.2% (95% CI 76.8%, 83.2%) in round 3 (May–October 2021) and the first 2 months of round 4 (November–December 2021).
Seroprevalence in Hong Kong HCWs in our study was low despite considerable exposure to confirmed COVID-19 cases in some study participants. However, the low rate of community transmission may have also contributed to the observed low seroprevalence among HCWs in our cohort.
There is an urgent need for effective interventions to aid diabetes-related foot ulcer (DFU) healing. This study aimed to test the deliverability of a proposed trial of extracorporeal shockwave therapy (ESWT) for DFU healing. A pilot double-blinded randomised controlled trial. Patients with a DFU present for ≥ 4 weeks were randomised to high dose (500 shocks/cm2), low dose (100 shocks/cm2) or sham (0 shocks/cm2) ESWT, plus standard care. Follow-up was for 24 weeks. Primary outcome was deliverability of the trial. Secondary outcomes were healing, quality of life and healthcare resource use. One-hundred and forty-one (15.6%) screened patients were eligible and 74 (52.5%) patients were recruited. Follow-up attendance was 97.3% (72/74), 93.2% (69/74) and 87.8% (65/74) at 6, 12 and 24 weeks. The median DFU healing time was high dose: 54.0 (IQR 119.0), low dose: 78.5 (IQR 61.0) and sham: 83.0 (IQR 85.0) days. The mean EQ-5D-5L utility value at 24 weeks was high dose: 0.621 (95% CI 0.438–0.804), low dose: 0.779 (95% CI 0.683–0.876) and sham: 0.806 (95% CI 0.717–0.895). Healthcare resource use was lowest in the low-dose ESWT arm. The pilot trial has demonstrated that patients with a DFU are willing to engage in the proposed trial and suggest the optimal way to deliver the definitive trial.