A study published in *Nature* (2020) evaluates the effectiveness of non-pharmaceutical interventions (NPIs) in containing the COVID-19 outbreak in China. Using epidemiological data and anonymized human movement data, the researchers developed a travel network-based SEIR model to simulate the spread of the virus across 340 prefecture-level cities in mainland China. The study estimates that there were 114,325 confirmed cases in China by February 29, 2020, with 85% in Hubei Province. Without NPIs, the number of cases would have increased by 67-fold, but the implementation of NPIs significantly reduced transmission. The study highlights that early detection and isolation of cases were more effective than travel restrictions and contact reduction in preventing infections. However, combined NPIs achieved the strongest and most rapid effect on outbreak containment. The lifting of travel restrictions on February 17, 2020, did not lead to an increase in cases if social distancing measures were maintained, even at a limited level. The study also shows that the timing of NPIs significantly affects the outcome, with earlier implementation leading to a dramatic reduction in cases and a smaller geographic spread. The findings suggest that China's aggressive and multifaceted response helped prevent a worse global spread of the virus. The study emphasizes the importance of timely and effective NPIs in controlling outbreaks, and provides insights into the role of population movement and close contact in the spread of the virus. The results also highlight the need for continued NPIs to sustain control of the outbreak, especially as travel and work resume. The study's model accounts for daily interactions, interventions, and statistical uncertainty, providing a robust framework for assessing the effectiveness of NPIs in different scenarios. The study has limitations, including potential underestimation of asymptomatic cases and biases in mobile phone data. Overall, the study contributes to a better understanding of NPIs and informs global efforts to contain the spread of COVID-19.A study published in *Nature* (2020) evaluates the effectiveness of non-pharmaceutical interventions (NPIs) in containing the COVID-19 outbreak in China. Using epidemiological data and anonymized human movement data, the researchers developed a travel network-based SEIR model to simulate the spread of the virus across 340 prefecture-level cities in mainland China. The study estimates that there were 114,325 confirmed cases in China by February 29, 2020, with 85% in Hubei Province. Without NPIs, the number of cases would have increased by 67-fold, but the implementation of NPIs significantly reduced transmission. The study highlights that early detection and isolation of cases were more effective than travel restrictions and contact reduction in preventing infections. However, combined NPIs achieved the strongest and most rapid effect on outbreak containment. The lifting of travel restrictions on February 17, 2020, did not lead to an increase in cases if social distancing measures were maintained, even at a limited level. The study also shows that the timing of NPIs significantly affects the outcome, with earlier implementation leading to a dramatic reduction in cases and a smaller geographic spread. The findings suggest that China's aggressive and multifaceted response helped prevent a worse global spread of the virus. The study emphasizes the importance of timely and effective NPIs in controlling outbreaks, and provides insights into the role of population movement and close contact in the spread of the virus. The results also highlight the need for continued NPIs to sustain control of the outbreak, especially as travel and work resume. The study's model accounts for daily interactions, interventions, and statistical uncertainty, providing a robust framework for assessing the effectiveness of NPIs in different scenarios. The study has limitations, including potential underestimation of asymptomatic cases and biases in mobile phone data. Overall, the study contributes to a better understanding of NPIs and informs global efforts to contain the spread of COVID-19.