**Background:** The current outbreak of novel coronavirus disease 2019 has caused a serious disease burden worldwide. Vaccines are an important factor to sustain the epidemic. Although with a relatively high-vaccination worldwide, the decay of …
The world has undergone five waves of COVID-19 pandemics, with a sixth wave likely to be led by China as policies in China begin to relax. We reproduced the multiple Omicron waves in Singapore using a multi-dimensional model. Our model shows that the …
**Objective:** This study uses four COVID-19 outbreaks as examples to calculate and compare merits and demerits, as well as applicational scenarios, of three methods for calculating reproduction numbers. **Method:** The epidemiological …