However, the mortality rate remains high in other nations, including the United States, Brazil, and India [1]. Taiwan has fought against the disease and has achieved successful containment of the infection keeping up to 253 days of zero confirmed domestic cases since the beginning of the overwhelming global situation of the pandemic in 2020 [2]. The dissemination of infection has been prevented by using vigorous national control measures, such as country border restrictions, proactive case identification using electronic contact tracing, quarantine of suspicious and confirmed cases, enhancing hygiene and sanitation, mandatory masking, social distancing, healthcare resource allocation, and efforts in reassurance and education of citizens [3; 4; 5]. However, a second-wave outbreak of the COVID-19 pandemic has emerged in North Taiwan since 14 May 2021 and has spread into other regions of the country. Taiwan is attacked majorly by SARS-CoV-2 variant B.1.1.7 which originated from the United Kingdom; however, a small proportion of the delta variant, also known as B.1.617.2, was also noted [6]. The two virus variants are more transmissible, more virulent, and may trigger more grave clinical conditions than non-variants lineage [7; 8]. As of 30 June, Taiwan has reached 14,804 laboratory-confirmed SARS-CoV-2 infection cases with an increasing death toll to 648 fatalities, especially in two hardest-hit areas, Taipei City and New Taipei City [9]. However, this community outbreak has been rapidly controlled nationwide. Sharing these experiences can certainly help in designing effective COVID-19 control measures in areas of similar socio-economic or epidemiological conditions. End-stage renal disease (ESRD) patients represent a vulnerable population with increased risks for COVID-19 infection and for related death [10]. In-center hemodialysis (HD) is currently the most common renal replacement therapy modality for ESRD patients worldwide [11]. The regular needs of visiting a medical facility to receive their dialysis treatment, often confined in crowded spaces, make it difficult to comply with some of the effective protective measures, such as stay-home orders, social distancing, and reducing personal contacts. The risks of mortality in SARS-CoV-2 infected people include older age, presence of comorbidities, and immune dysfunction [12; 13]. HD patients are often elderly and immune-dysregulated, owing to uremia, underlying comorbidities, and dialysis procedure-related biocompatibility and micro-inflammation [14]. Therefore, specific preventive methods to protect HD patients from COVID-19 infection remain urgently needed. Experiences of effective preventive strategies to combat secondary transmission of COVID-19 in HD units remain limited. Keelung City, 30 km away from the hotspot area of the pandemic, has become a region of alert for the prevention of community spreading of the disease. Taking appropriate measures immediately in the HD unit is the top priority to hamper the dissemination of the disease. The common preventive strategies adopted in the HD unit comprise the use of independent ward or cohort isolation, hand sanitizing, quarantine, and effective personal protective equipment [10]. However, the infection rate remains still high in HD units in spite of the application of all these methods [10]. Taiwan has the highest prevalence of ESRD worldwide [11]; however, the estimation of incidence and outcome of COVID-19 infection in Taiwanese HD patients is unclear. In spite of national and official public health policies to fight against COVID-19, effective preventive strategies to impede the secondary transmission of COVID-19 in HD units remain to be established. The aim of this study was to design a series of preventive measures to fight against the spreading of SARS-CoV-2 infection among HD units and to evaluate the effectiveness of these measures on the incidence of COVID-19 and related prognosis of HDpatients in this era of crisis.