Epidemiological characteristics of the three waves of COVID-19 epidemic in Taiwan during April 2022 to March 2023.

BACKGROUND: Taiwan experienced a relatively low incidence of COVID-19 before 2022. However, from April 2022 to March 2023, the country was struck by a nationwide outbreak that occurred in three waves. Despite the considerable magnitude of the epidemic, the epidemiological characteristics of this outbreak have yet to be clearly understood. METHODS: This was a nationwide, population-based, retrospective cohort study. We recruited patients who had been confirmed as domestically-acquired COVID-19 patients from April 17, 2022, to March 19, 2023. The three epidemic waves were analyzed in terms of numbers of cases, cumulative incidence, numbers of COVID-19-related deaths, mortality, gender, age, residence, SARS-CoV-2 variant sub-lineages, and reinfection status. RESULTS: The numbers of COVID-19 patients (cumulative incidence per million population) were 4,819,625 (207,165.3) in the first wave, 3,587,558 (154,206.5) in the second wave, and 1,746,698 (75,079.5) in the third wave, showing a progressive decline. The numbers of COVID-19-related deaths and mortalities also decreased throughout the three waves. The coverage of vaccination was observed to increase over time. CONCLUSION: During the three waves of COVID-19 epidemic, the numbers of cases and deaths gradually declined, while the vaccine coverage increased. It may be appropriate to consider easing restrictions and returning to normality. However, continued monitoring of the epidemiological situation and tracking the emergence of new variants are crucial to prevent the possibility of another epidemic.

An outbreak of SARS-CoV-2 infections among people living with HIV and its successful containment-Taiwan, May to August 2021.

In Taiwan, 14,308 locally acquired COVID-19 cases among customers and employees in Sexy Tea shops were the first cases from May 9-August 28, 2021 (weeks 19-34). Nine weeks after the community spread of COVID-19 began, the proportion of people living with HIV (PLHIV) among the COVID-19 patients peaked at 35.7%, affecting 192 HIV patients, while the prevalence of HIV infection was 0.15%. In addition to a nationwide Level 3 epidemic alert, the Taiwan Centers for Disease Control (Taiwan CDC) launched four strategies to contain this outbreak among PLHIV in this prevaccine era, including improving the quality of contact tracing, delivering health information via peer navigators, expanding SARS-CoV-2 screening and encouraging vaccination, and addressing hesitancy. The outbreak of COVID-19 related to Alpha strain among PLHIV in 2021 ceased four weeks after peaking and lasted eight weeks.

An Overview of the COVID-19 Pandemic and Risk Assessment, July, 2020

In late 2019, the novel coronavirus 2019 (COVID-19) outbreak was first identified in Wuhan, China, and subsequently spread worldwide. By July 11, 2020, the number of confirmed COVID-19 cases reached 12,881,555 (including 599,146 deaths) in 187 countries/ territories. The pandemic has not reach its peak yet. The situations of epidemics in the United States, Central and South Americas, and South Asia were still serious. Some countries faced re-surging epidemic after lifting restrictions. In Taiwan, the first imported case and the indigenous case were reported on January 21, and 28, respectively. As of July 12, the cumulative number of confirmed cases was 451, including 360 imported cases, 55 indigenous cases, and another 36 cases of naval crew members aboard the Panshi fast combat support ship. Currently the COVID-19 cases in Taiwan were still sporadic imported cases. No locally-acquired case was found for more than 8 weeks. Based on the current epidemic status, the risks of imported cases are still high. The high transmissibility of the virus and the potential of community outbreak remained as a threat to Taiwan's health system and society. Therefore, the overall risk of COVID-19 is considered high domestically.